Apex Final 1

Bupivacaine (Marcaine) - spinal

0.75% in Dextrose (Hyperbaric) • Dense Block • Gives up to a T4 block (2mL) • Great for Longer Procedures • LE Anesthesia = 3 hours • Dose 1.6-2mL (12mg-15mg) 0.5% (Isobaric) • Same duration & relative density of the 0.75% • Use primarily when 0.75% is on shortage • Great for Lateral procedures (Total Hip) • Dose - 2.5-3mL (12.5-15mg) • Off Label Use

Bispectral Index (BIS)

0: absence of cerebral activity 20: Burst suppression 40: Deep hypnotic state 40-60: GA 80: Light to moderate sedation 100: Fully awake

Direct laryngoscopy anatomy

-Larynx starts at epiglottis -Internal to larynx=articulating cartilages, arytenoids, epiglottis -Epiglottis, superior, and interior valeculla

Anesthetic considerations for acute intoxication

-Less anesthesia is needed -Aspiration precautions -Surgical bleeding ↑(inhibits platelet aggregation) -The brain is less tolerant of hypoxia -↑circulating catecholamine, labile VS and exaggerated responses to drugs and stimuli

Anesthetic mgmt of parkinsons

-Levodopa half life 6-12 hours. Should be taken morning of surgery. Must be administered via OG for longer procedures -Antidopaminergic drugs are contraindicated (metaclopramide, haloperidol, droperidol, promethazine) -Anticholinergics can be used to treat exacerbations -No contraindication to NMB's -Do not use alfentanil or Ketamine

Key facts about MAC

-MAC is a measure of anesthetic potency -its additive -movement can be prevented in 95% of the population at 1.3 MAC -Awareness and recall is presumed to be prevented at 0.4-0.5 MAC

myasthenia gravis treatment

Anitcholinesterase = oral pyridostigmine is first line tx OD can cause cholinergic crisis and muscle weakness Immunosuppression = steroids, cyclosporine, azothioprine, mycophenolate Surgery = Thymectomy - median sternotomy or transcervical approach Plasmaphoresis = temporary relief during myasthenic crisis or b/f thymectomy

Becks syndrome

Another name for ischemia of Adamkiewicz artery s/s: -flaccid paralysis of LE's (motor) -Bowel and bladder dysfunction (motor) -Loss of temp and pain sensation (spinothalamic) -Preserved touch and proprioception (dorsal column)

Preventing aspiration

Antacid preop (bicitra) Reglan Cricoid pressure Mild reverse trendelenberg Working suction

What makes up the anterior and posterior borders of the intravertebral foramina?

Anterior borders: vertebral body and intravertebral discs Posterior borders: fcaet joints

What do MEPs test?

Anterior cord Anterior spinal artery Motor function - NO NMB's

L4 dermatome

Anterior knee

Pancreatic txp labs

C-peptide: precursor insulin molecule, marker for lack of insulin secretion. blood glucose (hourly and after graft), Hgb A1C, electrolytes, BUN, creatinine, and possibly a liver function panel. Hematologic and coagulation studies Type and screen Correct hyperkalemia Metabolic panel q 30 min intraop

Chronic hepatitis

Hep B: 1-10% Hep C: 10-40% -Chronic persistent (relatively benign and confined to portal areas) -Chronic lobular (recurrent exacerbations of acute inflammation -progression to cirrhosis rare) -Chronic active (most serious, progressive form)

Pulmonary changes in liver dx

Hepatopulmonary syndrome: pleural effusions & Pulmonary hypertension Acites pushes up on diaphgram ->mechanical ventilation decreased R-L shunting may cause hypoxemia High occurrence of COPD secondary to smoking

Factors that do not affect the reliability of pulse ox

Hgb S Hgb F Jaundice Fluerescein Polycythemia Acrylic finger nails

Renal elimination

Hydrophilic drugs (ionized) will be excreted unchanged Lipophilic drugs (unionized) will undergo biotransformation so they can be eliminated or they will be reabsorbed in the kidneys (via diffusion)

Most common LA to cause transient neurological symptoms (TNS)

Lidocaine

Factors that increase risk of TNS

Lidocaine, lithotomy position, ambulatory surgery, knee arthroscopy

Miller blade used to ____

Lift the epiglottis and compress it against the base of the tongue Child: 2 Adult: 3-4

Only ligament that is passed through with the paramedian approach

Ligamentum Flavum

Lipid Emulsion Therapy

Lipid emulsion 20% Bolus 1.5mL/kg lean body wt (100mL for 70kg pt) Continuous infusion 0.25mL/kg/min (up to 0.5mL/kg/min if BP remains low) repeat bolus once or twice for persistent CV collapse Continue infusion for at least 10 min after gaining CV stability Upper limit: 10mL/kg over first 30 min

IV agents to avoid in patient w/ history of seizures

Ketamine* (most important) Etomidate, Methohexital, Alfentanil increase EEG activity and can be used for cortical mapping Propofol has been implicated in seizures but it is still a first line drug for seizure activity

Cervical Spinal anomalies

Kids try gold Klippel-Feil Trisomy 21 Goldenhar

Examples of increased resistance

Kinked ETT bronchospasm mucus plug ETT cuff herniation compression of the airway foreign body aspiration

Disadvantage of Bain Circuit?

Kinking of the inner tube. This converts all corrugated tubing into dead space.

3 types of voltage gated calcium channels

L-Type = long lasting or slow channel N-Type = neural T-Type = transient

Lumbar plexus

L1-L4 I Invariably Get Lazy On Fridays Iliohypogastric Ilioinguinal Genitofemoral Lateral femoral cutaneous Obturator Femoral

lumbar dermatomes

L1: inguinal area, front pelvic bone region L2: Front, medial thighs, hips L3: back medial thighs, knees L4: medial calves, ankles L5: Lateral calves, top of foot

lateral femoral cutaneous nerve

L2-L3 Motor: None Sensory: Lateral thigh

Obturator Nerve

L2-L4 Arises at the sscroiliac joint Motor: Hip adductors Sensory: Distal inner thigh and part of the hip

Femoral nerve

L2-L4 Motor anterior branch: Sartorius Motor posterior branch: Quadriceps Sensory: Anterior thigh

which has a greater volume of distribution water or lipid soluble drugs

Lipid soluble. The more ionized a molecule is the lower volume of distribution it has water soluble = ionized being water soluble and ionized increases the delivery of the molecule to the kidneys. The ionization will prevent reabsorption in the kidney tubules

2 major organs unaffected by neuraxial anesthesia

Liver and kidney (As long as blood flow remains constant)

Conditions that decrease specific gravity

Liver disease Jaundice Warmer temperature

Conditions that decrease specific gravity

Liver disease Jaundice Warmer temperatures

How to calculate loading dose

Loading dose = (Vd x Desired plasma conc.)/Bioavailability For IV drugs bioavailability is 1 b/c they are injected directly into plasma. So for IV drugs you can take: Vd x desired plasma concentration

Focal cortical seizure

Localized to a particular focal region -Can be sensory or motor -usually no LOC

epidural anatomy

Located b/w the dura and the walls of the vertebral canal -bound anteriorly by posterior longitudinal ligament -laterally by vertebral pedicles, -posteriorly by ligamentum flavum and vertebral lamina Unlike the subarachnoid space, it is not a closed space.

Sidestream (Diverting)

Located outside the airway pumping mechanism continuously aspirates gas sample slower response time requires water trap to prevent contamination

Pseudocholinesterase

enzyme that rapidly destroys certain drugs in the plasma -produced in liver - can be used as measure of hepatic fxn -Found in skeletal and smooth muscle, white matter of brain, intestines, heart, and pancreas (not found in CSF)

What is contraindicated with a wrist block

epi solutions

Result of injecting local anesthetic into the subdural space

epidural dose: high spinal spinal dose: failed spinal

major complication of neuraxial anesthesia

epidural hematoma -> compresses the dura -> spinal cord ischemia tx: surgical decompression w/in 8h

intrathecal vs epidural opioid dosing

epidural opioids need to diffuse through the epidural space and the dural cuff so only a fraction reaches the spinal nerve -> need a higher dose

What drug inhibits alfentanil's metabolism

erythromycin (renal failure does not alter alfentanil's clearance)

PAOP

estimation of the CVP of the left heart A wave = left atrial systole C wave = MV bulging into LA during LV contraction V wave = passive LA filling

At atmospheric pressure and room temp what form does each category of inhaled anesthetic take

ethers: liquid alkanes: liquid gases: gas

Cholethiasis

gallstones cholecysectomy

grand mal seizure (tonic-clonic seizure)

generalized seizure tonic phase = whole body rigidity clonic phase = jerking movements respiratory arrest -> hypoxia increased brain activity -> ↑CMRO2

Malignant hyperthermia

genetic disease characterized by disordered calcium homeostasis - dysfunctional ryanodine receptor (doesn't turn off, ca+ keeps pumping out) SERCA pump also keeps working. They both use up ATP causing lactic acidosis

saddle block

given at the lower end of the spinal column (sacrum) to block the perineal area, or hyperbaric solution in lumbar w/ sitting position maintained until block sets up.

Defasciculating dose

giving a little NDNMB before Succ -get the speedy intubation conditions of succ and avoid fascicluations which can increase ICP, IOP and cause postop muscle aches.

Where do most neurologic tumors arise from

glial cells

What are associated causes of cauda equina?

microcatheters, small needles and repeat dosing of hyperbaric LA -microcatheters focus LA on a small area of the spinal cord, exposing this region to high concentrations of LA. -FDA removed small needles and microcatheters in 1992

Uptake of N2O by tissue types

minimal - will collect in gas-filled spaces like the middle ear and bowel

TOF fade

caused by antagonism of presynaptic neuron. -binding of ACh to presynaptic neurons leads to feed-forward release mobilization of more ACh. NDNMB's bind to the Nn receptor and block ACh from binding. -Initial stimulation causes release of ACh, but because of the antagonism, a new supply of ACh is not mobilized and the twitch "fades" out.

Constrictive pericarditis

caused by fibrosis or anything that makes the pericardium thicker. Ventricle can't relax = decreases compliance and limits diastolic filling = ↓CO Cause = cancer (radiation), cardiac surgery, RA, TB, uremia

systolic anterior motion (SAM)

caused by the venturi effect as blood rapidly flows across the LVOT (velocity increases through a point of stricture) -diagnosed w/ TEE -can occur post MV repair (not replacement)

Hematoma

causes compartment like syndrome that compresses the nerve and causes paralysis. This is a more common cause of paralysis that puncture of nerve.

Etomidate affect on EEG

causes myoclonus NOT epileptiform activity

Morphine-6-glucuronide

causes: respiratory depression, n/v, drowsiness, and coma water soluble=does not cross BBB pt's on dialysis accumulate this metabolite causing enough of a concentration gradient that it can cross the BBB (more likely to experience toxicity - respiratory depression)

Initial anesthetic considerations w/ TBI

cervical spine stabilization airway protection optimization of hemodynamics cerebral protection

vertebral column sections

cervical: C1-7 thoracic: T1-12 lumbar: L1-5 sacrum: S1-5 fused coccyx: 4 fused

Mendleson's Syndrome

chemical pneumonitis or aspiration pneumonitis caused by aspiration during anesthesia

Pancreatic exocrine hormones

cholecystokinin-pancreozymin (CCK-PZ) Secretin Both hormones are produced in the duodenum, jejunum, and the ileum

Independent risk factors for AAA

cigarette smoking male gender Advanced age

most common site of cerebral aneurysm

circle of willis

where do the anterior and posterior circulation converge

circle of willis = its purpose is to provide redundancy in the blood flow to the brain, so if one part is compromised the other part can provide perfusion

Electrocautery and pacemakers

coagulation setting causes more EMI than cuting monopolar causes more EMI than bipolar or ultrasonic harmonic scalpel if using monopolar need short burst (<0.5 sec) risk of EMI is highest when electrocautery tip is w/in 15 cm radius of pulse generator Return pad should be placed far away from pulse generator and in a location that prevents a direct line of current thru the pulse generator

CYP 2D6

codeine -> morphine oxycodone hydrocodone -inducers: carbamazepine, phenytoin, dexamethasone -inhibitors: SSRI's, isoniazid, Quinidine

Cerebral cortex

cognition sensation movement

Pancreatic pseudocyst

collection of debris, fluid, pancreatic enzymes, and blood as a complication of acute pancreatitis

ganglion

collection of nerve cell bodies that reside outside of the CNS

enzyme inhibitor

competes for binding sites on an enzyme -decreases drug clearance and increases half time grapefruit SSRI's cimetidine omeprozole isoniazid erythromycin ketoconazole

CPB roller pump

compresses blood tubing as it mechanically propels blood forward -causes trauma to the cells -pump remains constant regardless of pt afterload or potential upstream occlusion (clamped tubing) -more likely to entrain air if the venous reservoir runs dry

What causes increased compliance

conditions that dilate the heart -chronic aortic insufficiency -dilated cardiomyopathy

intercristal line

connects the iliac crests at L4-L5 interspace in the lateral decubitus position Also called touffier's line

First order kinetics

constant percentage of substrate is metabolized per unit time -> constant fraction per time -there is less drug than enzyme -accounts for most of the drugs we give

2 routes infectious organism can reach the CSF

contaminated needle (breech of aseptic technique) bacteria in patients blood at time of SAB

enterohepatic circulation

continual recycling of compounds like bile acids between small intestine and liver -can happen with drugs where they are excreted in the bile but then reabsorbed and reactivated in the small intestine. example: diazepam

Capnography

continuous measurement of metabolism, circulation, and ventilation CO2 is the final product of aerobic metabolism

Sphincter of Oddi

controls the flow of bile released from the common hepatic duct contraction increases biliary pressure (narcotics - esp morphine)

Landmark that marks the end of the spinal cord

conus medullaris: L1-L2 (adults) /L3 (kids)

Most common periop eye complication

corneal abrasion

portions of spinal cord perfused by the anterior blood supply

corticospinal tract (flaccid paralysis) Autonomic motor fibers (bowel & bladder dysfxn) Spinothalamic tract (loss of pain & temp sensation) (touch and proprioception are from the dorsal column supplied by the posterior blood supply)

MS treatment

corticosteroids interferon azathioprine

Arterial waveform morphology

optimally dampened: baseline re-established after 1 oscillation Under-dampened: baseline re-established after several oscillations (SBP is over estimated, DBP is underestimated, MAP is accurate) Over-dampened: baseline re-established with no oscillations (SBP is under estimated, DBP is over estimated, MAP is accurate)

Naltrexone

oral opioid antagonist Duration: 24h unlike naloxone it does not undergo significant first pass metabolism

A flutter

organized supraventricular rhythm (sawtooth) defined ration of a:v contraction refractory period prevents all atrial conductions from being conducted to ventricles Tx: rate control or cardioversion (starting at 50j) aflutter indication to cancel surgery

PVC

originate from foci below the AV node wide QRS Unifocal: arise from single location Multifocal: arise from numerous locations (different QRS morphologies

Mannitol

osmotic diuretic dose: 0.25 - 1g/kg MOA: increases serum osmolarity which increases pull of water across the BBB if the BBB is disrupted Mannitol enters the brain and increases cerebral edema causes transient increase in overall blood volume, can stress the failing heart

Reduced ventricular compliance causes the CVP and PAOP to _________________ the LVEDV

overestimate

Most common problem w/ Pagets

pain and bone fractures

Pain Transmission

pain signal is relayed through the three neuron pain pathway along the spinothalamic tract

pain modulation

pain signals can be inhibited or facilitated as they travel along sensory pathways; this can occur wherever there is a synapse

Pancreatitis s/s

pain, loss of appetite or unintended weight loss, depression, new=onset diabetes, blood clots, fatigue, and jaundice

Which NMB has a vagolytic effect?

pancuronium

Treatment for chest wall rigidity

paralysis and intubation Naloxone can also reverse but this is not wise to do prior to surgery

Cardioplegia

paralysis of heart muscle Potassium solution arrests the heart in diastole by increasing RMP - activates Na+ channels and maintains them in the inactive state Antegrade: aortic root -> coronary arteries = need a competent aortic valve Retrograde: through cannula placed in coronary sinus a/e: can cause heart block, that's why heart is paced after bypass

injury to lower motor neurons

paralysis on the same side of the body as the injury presents w/ impaired reflexes and flaccid paralysis Babinski sign is absent

What does a wake up test, test for?

paraplegia This has been replaced by MEP & SSEP

Third order neuron (Anterolateral)

pass through the internal capsule and advance toward the somatosensory cortex in the postcentral gyrus in the parietal lobe Most pain fibers synapse in the RAS and then connect to the thalamus

Third order neuron (Dorsal)

pass through the internal capsule and advance towards the somatosensory cortex in the postcentral gyrus in the parietal lobe

Sign of pneumo

patient coughs or complains of pain at needle insertion

Transient Neurologic Symptoms (TNS) cause

patient positioning stretching of the sciatic nerve myofascial strain muscle spasm

Why are peds more susceptible to bradycardia caused by Succ

peds have a higher baseline vagal tone give atropine b/f (esp 2nd dose)

VIA and peripheral chemoreceptor

peripheral chemoreceptors are impaired for up to several hours after surgery N2O also impairs carotid bodies response to hypoxemia but for a different reason

innervates the diaphragm

phrenic nerve

Pharmacodynamics

physiological and biochemical mechanism of action of drugs What the drug does to the body -effect site concentration and clinical effect receptor theory=binding causes effect

Stimulation of the tibial nerve results in?

plantar flexion and inversion of the foot TIPPED

Guillane Barre treatment

plasmapheresis &/or IV IgG (Unlike MS - steroids and interferon do not help)

Low EtCO2 capnography

plateau phase way below normal Occurs with hyperventilation, ↓CO2 production, or ↑alveolar dead space Examples hyperventilation: metabolic acidosis, light anesthesia Examples ↓CO2 production: hypothermia Examples ↑alveolar dead space: hypotension, pulmonary embolism

Complications of pericardiocentesis or pericardiostomy

pneumothorax, re-accumulation of fluid, puncture of the coronary vessels or myocardium

Where is ETCO2 measured?

point D

How does inspiration affect SV?

positive pressure breath augments LV filling (RV filling is impeded d/t compression of returning blood) Increased LV filling increases SV (Starling)

Tibial nerve

posterior and medial sits behind the posterior tibial vein and artery

Cords

posterior: C5-T1 medial: C5-C7 lateral: C8 -T1

transmural pressure

pressure difference exerted on the two sides of a wall -LV v aorta increasing transmural pressure helps keep the LVOT open (ie maintaining afterload)

What is most likely the primary mechanism of inhibition for edrophonium

presynaptic

enzyme induction

process by which the presence of a chemical that is biotransformed by a particular enzyme system in the liver causes an elevation of hepatic drug-metabolizing enzymes. Can result in increases in the metabolism of a variety of substrates (not just the chemical that stimulate the upregulation). Enzyme induced=requires more drug, or could cause toxicity if metabolite is toxic or more potent

pain perception

processing of afferent pain signals in the cortex and limbic system.

ependymal cells

produce cerebrospinal fluid form the choroid plexus - located in all 4 ventricles

amyotrophic lateral sclerosis (ALS)

progressive degeneration of motor neurons in the corticospinal tract Upper and lower motor neurons are affected

Transverse processes

project laterally from the right and left sides of the vertebral arch muscular attachment

spinous process

projects posteriorly Denotes the midline

Myotonic Dystrophy

prolonged contracture after voluntary muscle contracture Cause: dysfunction ca+ sequestration by the sarcoplasmic reticulum Contractures can be so severe they interfere w/ intubation and ventilation

Clinical presentation of Eaton-Lambert

proximal muscles are most affected weakness is worst in the morning and gets better throughout the day weakness of respiratory and diphragm muscles ANS dysfxn cause orthostatic HoTN, slowed gastric motility, urinary retention

4 key metabolic pathways in the plasma

pseudocholinesterase Non-specific esterases Alkaline phosphatase Hoffman elimination

Secondary signs of Parkinson's

psychosis depression dementia loss of facial expression diaphragmatic spasm oculogyric crisis

Horner's syndrome symptoms

ptosis, myosis, anhydrosis

T12 dermatome

pubic symphysis

What do elevated filling pressures put pt's at risk for

pulmonary edema

Cushings triad

r/t ICP = HTN, bradycardia, irregular respirations

3 terminal nerves that can be blocked at the forearm or wrist

radial, ulnar, median

Stimulatory receptors

receptors that anesthetics inhibit NMDA receptors Nicotinic receptors Sodium channels (cause depolarization) Dendritic spine function and motility

Inhibitory receptors

receptors that anesthetics stimulate GABA-A receptors Glycine channels Potassium channels (causes hyperpolarization)

Local anesthetics effect on seizures

reduce the seizure threshold, but regional anesthesia does not increase the risk for seizures

Cause of drowsiness with neuraxial anesthesia

reduces sensory input to the Reticular Activating System (RAS), causing drowsiness.

CNS affects of neuraxial anesthesia

reduces sensory input to the reticular activating system. This can cause drowsiness

CPB centrifugal pump

uses gravity and spins the blood through a cone -less traumatic to blood cells Less risk of entraining air b/c it does not build up excessive negative pressure Also not able to build up excessive positive pressure so pump slows down when it encounters excessive afterload No occlusion point so if flow slows down d/t afterload it will back up into venous circulation

CV affects of Neuraxial anesthesia

vasodilates arterial and venous, but mainly affects venous capacitance. ↓venous return, CO & BP treat w/ volume

Protamine adverse effects

vasodilation (give over 10-15 min) pulmonary vasoconstriction risk of anaphylaxis

Leading cause of morbidity and mortality after subarachnoid hemorrhage

vasospasm

Batson's plexus in the epidural space is an extensive network of veins (with/without) valves These veins anastomose freely with ______ veins

venous drainage system in the epidural space is an extensive network of veins (with/without) valves

What CCB's are best for reducing heart rate w/ tachycardia or afib/a flutter

verapamil and diltiazem

occipital lobe

visual processing

Clearance

volume of plasma cleared of drug per unit time

Anticoagulated pt w/ TBI

warfarin reversal: FFP, prothrombin complex concentrate, recombinant factor VIIa Anti-platement med: Platelet infusion

Modern anesthesia

we use small doses of many drugs to minimize s/e and make sure they wear off quickly so people can wake up.

Preload responsiveness

when a 200-250mL fluid bolus improves SV more than 10% the first fluid bolus should increase it >10% the second fluid bolus should increase it ~3% Once additional fluid boluses no longer improve the SV you've reached the optimal position on the starling curve - additional fluid will not help

Bromage Grip

• Nondominant hand grasps needle hub b/w pointer and thumb • Back of hand/fingers brace against pt's body • This will then stabilize your access point

epidural

• Onset - Variable • Duration - Variable • Density - Variable • "Customizable" Benefits: can do at any level of the spine, a catheter can be placed Cons: technique takes longer, slower onset, and potentially less dense block

spinal

• Onset: Quick • Duration: Set • Density: Set • Once injected it's done

TNS - Transient Neurological Symptoms presentation

• Pain in buttocks that radiates to both legs • Bowel Bladder Dysfunction • Typically resolve on their own • Develops within 6-36h and resolves within 1-7 days

Post op complications

• Post Dural Puncture Headache (PDPH) • Urinary Retention • Backache • TNS (Transient Neurologic Syndrome) • Cauda Equina Syndrome • Infection • Nerve Injury -> bleeding

Relative contraindications to neuraxial anesthesia

• Previous Spine Surgery (related to viability of block rather than complication) • Evidence for most other neurological issues are not rooted in evidence: Back Pain, Neuropathies, Spinal Stenosis, MS, etc. • Spina Bifida - ↑risk to neurological structures • Aortic Stenosis • Hypovolemia • Thromboprophylaxis • Coagulopathies • Concern when PLT <100,000 (not a hard #) • PT or aPTT are x 2 normal • Infection • Peripheral neuropathy (more of a legal landmine than fact-based)

Neurological Injury

• Rare • The "typical" concern of receiving a spinal • Causes: Needle Trauma, Surgical, Positional Chemical (drug-glass particles), Virus, Bacteria Ischemic - Hematoma

What does the interspinous ligament join

• Runs parallel to and joins the spinous processes • Very thin

Spinal complications

• Total Spinal • Cardiac Arrest • Failed Spinal • GI Complications • IV Injection/ Local Toxicity

Controllable factors that contribute to spread of LA for spinal

• Total dose of drug (volume) • Site of injection • Baricity of the drug • Patient position after injection

Epinephrine

• Typical dose is 0.1-0.2 mL of 1:1000 (1mg/mL) • ~100mcg • "Epi-Wash": Aspirate the entire 1mL of 1:1000 into delivery syringe and then squirt it out. A small amount of epi remains - this is easier than drawing up 100mcg

GI effects of Neuraxial anesthesia

• Unopposed vagal tone (typically Inhibited sympathetic tone) • Increased peristalsis • Relaxed sphincters

Adjuncts

• Vasoconstrictors (epi) • Alpha-2 agonists (clonidine, precedex) Extend duration of block

Epidural issues

• Wet Tap • Aspirate blood • Not on midline • Paresthesia • Inability to pass catheter • Inadequate block • One Sided • Hot Spot • NEVER withdraw a catheter back out of a needle once advancement occurs - may sheer it off into the epidural space

Caudal Anesthesia

• pediatrics due to ease of access • Prone or Lateral position • Palpate Cornua of the sacral hiatus • Needle advanced at steep angle b/w the cornua • Popping sensation appreciated when entering the ventral canal of the sacrum • Needle angle is then lowered to be parallel w/ the sacrum/spinal canal • Needle advanced 1-3 cm • Medication injected or catheter over needle technique to place catheter.

Paramedian Approach

• ~1" off midline in ~15 degree approach • Avoid horizontal anatomy

Pre-anesthetic risk factor for layrngospasm

•Active or recent URI •Exposure to second hand smoke •Reactive airway dx •GERD •Age < 1 yr

What to do in the case of aspiration with an LMA

•Leave the LMA in place •Trendelenberg position •100% O2 via ambu •low fgf and low TV •Suction through LMA •Evaluate for presence of gastric contents in sxn'd material

OR risk factor for layrngospasm

•Light anesthesia •Blood or saliva in airway •Hyperventilation •Hypocapnia •Surgical procedure involving the airway (tonsillectomy, adenoidectomy, nasal/sinus, laryngoscopy, bronchoscopy, palatal)

hepatorenal syndrome

•Liver failure causes a hyper dynamic circulation •decreased GFR stimulate RAAS which leads to water and sodium retention •This can cause hyponatremia (dilutional) •Increased BUM comes from the failing liver being able to clear nitrogenous waste (this can lead to cerebral edema

LMA Contraindications

•Risk of Aspiration: Full stomach, hiatal hernia, small bowel obstruction, GERD, delayed gastric emptying. •Obstruction at the level of or below the glottis (tracheal tumor) •Poor Lung compliance •High airway resistance Asthma is indication for LMA

3-3-2 rule

•mouth opening should be at least 3 fingerwidths (5cm). •Thyroid Mental Distance (TMD) 3 fingerwidths (6cm) is optimal. •distance from the hyoid bone to the thyroid notch should be at least 2 fingers wide.

Chronic systolic HF

↑ EDV, EDP, ESV ↓ SV ↑ LV Mass Eccentric hypertrophy

anaerobic effect of cross clamp

↑ lactic acid ↑ prostaglandins ↑ activated complement ↑ myocardial depressant factors ↓temp

Physiologic changes with clamp placement

↑ venous return ↓/0 CO (depends on CV reserve) ↑Preload MAP, and SVR ↑ Catecholamine release and RAAS activation ↑ LV wall stress ↑ MVO2 (myocardial O2 demand) ↑ coronary blood flow ↓Renal blood flow ↓ total body VO2 -> ↓O2 delivery to lower body ↑SVO2

VAE signs

↑EtCO2 ↑EtCO2 & PaCO2 gradient

Hemodynamic effect of N2O

↑HR ↑/0BP ↓CO (potentiated by opioids) ↑SVR Effects are explained by SNS activation

Hemodynamic effect of Des

↑HR ↓BP ↓/0 CO ↓SVR HR is increased 5-10% most likely d/t to ↑SNS activation (ie beta 1 stimulation) from respiratory irritation - can lead to tachycardia

Hemodynamic effect of Iso

↑HR ↓↓BP ↓ CO ↓SVR HR is increased 5-10% most likely d/t to ↑SNS activation from respiratory irritation Dilates coronary arteries the most - that's why it is thought to cause coronary steal

Interventions for increased O2 demand

↑HR: BB to HR < 80 ↑BP: increase anesthesia depth, vasodilator ↑PAOP: Nitro

Electrolyte potentiation of NMB's

↑Lithium: Activates K+ channels ↑Magnesium: ↓presynaptic Ach release ↓Calcium: ↓presynaptic Ach release ↓Potassium: ↓RMP

Cardiac considerations of scoliosis

↑PVR -> RV hypertrophy Mitral valve prolapse Mitral valve regurg Coarctation of the aorta

Autonomic changes in liver dx

↑RAAS, ↑SNS output

N2O affect on EEG

↑beta activity

Sphincter of Oddi spasm

↑biliary pressure narcotic induced Morphine> meperidine > butorphanol > nalbuphine Prefer synthetic narcotics FENTANYL Other causes: Surgical manipulation, cold irrigation, contrast dye

Conditions that distend the LVOT (good)

↑systolic volume (↑preload or ↓HR) ↓contractility ↑Ao pressure

Physiologic changes with clamp removal

↓ venous return (central hypovolemia & cap leak) ↓/0 CO (↓preload and contractility) ↓Preload ↓ MAP, and SVR (washout of metabolic waste - vasodilation) ↑ PVR -> ↑PAOP (↑ lactic acid/↓pH) ↓ LV wall stress ↓ MVO2 (myocardial O2 demand) ↓ coronary blood flow ↑Renal blood flow ↑ total body VO2 -> O2 delivered to lower body ↓SVO2 (more O2 consumed - less left over)

Effects of priming CPB w/ balanced salt solution

↓HCT ↓oxygen carrying capacity ↓blood viscosity (can be good if hypothermia is used) ↓plasma concentration of drugs and plasma proteins ↑microvascular flow (fxn of reduced viscosity)

Hemodynamic effect of Xenon

↓HR 0 BP 0 CO 0 SVR

cardiac tamponade pressure volume loop

↓LVEDV (shift to the left) ↓SV (narrower) ↓ventricular compliance

Pulsus paradoxus

↓SBP > 10mmHg during inspiration - indicative of impaired diastolic filling inspiration causes increased intrathoracic pressure, this compresses the heart -> decreases filling capacity -> decreases CO -> decreases BP when the heart is experiencing cardiac tamponade or constrictive pericarditis this compounds the problem and you get a larger drop in BP

Conditions that narrow the LVOT (not good)

↓systolic volume (↓preload or ↑HR) ↑contractility ↓Ao pressure

Carcinoid s/s

■Cutaneous flushing (kinins, histamine) ■Bronchospasm (serotonin, bradykinin, substance P) ■Profuse Diarrhea (serotonin, Prostaglandins) ■Heart Disease ■Tricuspid regurgitation, pulmonic stenosis, SVT's (serotonin) ■Labile hemodynamics: Hypertension (serotonin), Hypotension (kinins, histamine) ■Abdominal pain (small bowel obstruction) ■Hepatomegaly (metastasis) ■Hyperglycemia ■Hypo-albunemia

Diphenylheptanes

Methadone

Which opioid causes QT prolongation

Methadone

Which opioid is an NMDA receptor antagonist

Methadone

Drugs that prolong QT interval

Methodone Droperidol Haloperidol Ondansetron Halogenated anesthetics Amiodarone Quinidine Sotalol

2 classes of ethers and their agents

Methyl-isopropyl ether: Sevo Methyl ethyl ether: Iso and Des

Which opioid antagonist should not be used to reverse respiratory depression?

Methylnaltrexone = Does not cross BBB Used to reverse constipation while not reversing analgesia

Drugs that reduce Pseudocholinesterase activity (ie prolong the duration of Succ)

Metoclopromide Neostigmine Esmolol MAOIs Oral contraceptives/estrogen Echothiophate Cyclophosphamide

Chronic DM complications

Microvascular: Retinopathy, Neuropathy, Nephropathy Macrovascular: CAD, PVD, Cerebrovascular dx Infection, Cataracts, Stiff joint syndrome, Glaucoma, Poor wound healing

Intermediate extraction drugs

Midazolam Vecuronium Alfentanil Methohexital

Brainstem

Midbrain: auditory and visual tracts Pons: autonomic integration Medulla: autonomic integration Reticular activating system: controls consciousness, arousal, and sleep

Fixed airspaces

Middle ear Brain during intracranial procedures

effect of epidural opioids on breast milk

Minimal

Every 1mmHg increase in PaCO2 above baseline will increase _________

Minute ventilation by 3L/min

2 adverse effects of opioids you cannot develop tolerance to

Miosis and constipation

MELD score

Model for End-Stage Liver Disease Considers frequency of dialysis and lab values -INR -Serum Bilirubin -Serum Creatinine

What drug characteristics affect Vd?

Molecular size ionization protein binding

Stump perfusion

Monitors perfusion pressure in the carotid on the operative side -Risk of cerebral hypoperfusion is < 50 mmHg -shunt placed distal to cross clamp increases perfusion -shunt placement increases risk of stroke

Unacceptable response to twitch monitor (supraclavicular)

Pectoralis Bicep Deltoid

Unacceptable response to twitch monitor (infraclavicular)

Pectoralis Biceps Deltoid

Non-cutting tip

Pencil tip point: Sprotte, Whitacre, Pencan Rounded bevel tip: Greene

Non-cutting needles (spinal)

Pencil tip: Whitacre: Square hole Sprotte: oval hole Pencan Rounded bevel tip: Greene • side port shape for injection • 22-29 guage (24-29 guage require introducer)

Postsynaptic Nicotinic Receptors

Pentameric: 2 alpha, 1 beta, 1 delta, 1 epsilon subunits Each alpha subunit binds 1 ACh.

Partial agonist opioids

Pentazocine Nalbuphine Butorphanol Buprenorphine

CCK

Produced by I-cells in lining of the duodenum trigger for release: presence of fats and partially digested proteins in the duodenum improves digestion by slowing stomach emptying and stimulating the production of bile and its release from the gallbladder sensation of fullness in the short-term, during a meal

Secretin

Produced in crypts of Lieberkuhn in intestinal wall trigger for release: low pH in duodenum Fxn: Stimulates secretion of bile from the liver, alkaline pancreatic juice from the pancreas, and bicarb from duodenal Brunner's glands

Where is CSF produced and reabsorbed

Produced: Choroid plexus Reabsorbed: Arachnoid villi

Zones of the spleen

Red pulp: Splenic sinusoids (large thin-walled vessels) White pulp: End arterial branches of central arteries and contain lymphocytes, macrophages, and plasma cells Marginal zone: Ill-defined vascular space that contains white pulp and red pulp Blood flow is 300 mL/minute

Alzheimer's pathophysiology

Reduced ACh, Beta Amyloid Plaques, Neurofibrillary Tangles These cause: Dysfunctional synaptic transmission & Apoptosis Degeneration of Neurons: Early hippocampus/memory; Late cerebral cortex/speech/reasoning

How does neuraxial anesthesia affect respiratory mechanics

Reduced accessory muscle function (intercostal and abdominal muscles) - impaired inspiration and expiration Caution with COPD patients

Why do we measure alveolar concentration

Reflects the concentration in the brain alveolar partial pressure ~ blood partial pressure ~ brain partial pressure

fiberoptic bronchoscopy contraindications

Relative contraindications (no absolute contraindications) •Hypoxia (lack of time) •Secretions not relieved by sxn •Hemmorhage (unable to visualize) •Uncooperative pt •Local anesthetic allergy

Which opioid causes skeletal muscle weakness

Remi - do not administer in the epidural or intrathecal space

Drugs metabolized by Non-specific esterases

Remifentanil Esmolol (RBC esterases) atracurium (+Hoffman's) Etomidate (+ hepatic)

the only opioid that does not undergo hepatic biotransformation

Remifentanil - metabolized in the plasma by nonspecific esterases -> ester hydrolysis. Causes it to behave like a drug with a low Vd.

Renal changes w/ liver dx

Renal hypoperfusion -> ↓GFR -> ↑RAAS -> dilutional hyponatremia Protein loss and low oncotic pressure -> Ascites & Edema correct hypovolemia and diurese = Consider albumin, mannitol, potassium sparing diuretics

Renal complications from RA

Renal insufficiency d/t vasculitis and NSAIDs

List 7 causes of secondary hypertension

Renovascular disease Coartation of the aorta Hyperadrenocorticism (Cushing's) Hyperaldosteronism (Conn's disease) Pheochromocytoma Pregnancy-induced HTN

Recommendations for block placement/catheter removal: Unfractionated Heparin

SQ: Proceed if pt has normal clotting mechanism and is not on any other blood thinners IV: Hold 2-4 hours b/f block, and 1h after block placement Hold 2-4h after removing catheter

Neuraxial recommendations w/ unfractionated heparin

SQ: Proceed w/ block if pt is not on any other blood thinners and has normal clotting mechanisms IV: b/f block hold for 2-4 h after block hold for 1h b/f catheter removal hold for 2-4h

Drug Ionization

STEP 1: 1. If pH-pKa = 0 then ratio equals 50% 2. If pH-pKa = 0.5 the ratio equals 75/25% 3. If pH-pKa = 1 or greater then the ratio equals 99/1% To determine whether it's ionized or not: STEP 2 1. acids in acid pH = non-ionized 2. bases in basic pH = non-ionized 3. acids in basic pH = ionized 4. bases in acid pH = ionized

What values can be derived from esophageal US/doppler

SV=vol ejected from LV per beat SVI= SV indexed to BSA SVV= change in SV per beat Stroke Distance= how far SV is pumped per beat Peak Velocity= index of contractility Flow time= time b/w aortic opening and closure Flow time corrected= flow time indexed to a HR of 60bpm

Pediatric dosing for caudal block: sacral and thoracic level

Sacral: 0.5 mL/kg Sacral to low Thoracic (~10): 1 mL/kg Higher block levels are not recommended for this technique

lumbosacral plexus

Sacral: L4-S4 Posterior femoral cutaneous Sciatic: Common Peroneal (superficial perorneal, deep peroneal, surral), Tibial (Surral, posterior tibial)

Caudal border of the epidural space

Sacrococcygeal ligament

Volatile anesthetics effects at their target receptors

stimulate inhibitory receptors inhibit stimulatory receptors

Glucagon MOA

stimulates glucagon receptors on myocardium -> increases cAMP -> increases HR, contractility & AV conduction

enzyme inducer

stimulates synthesis of additional enzyme -increases drug clearance and decreases half time tobacco smoke barbituates phenytoin rifampin ethanol carbamazepine

autonomic hyperreflexia pathophysiology

stimulation below the level of the SCI -> HTN -> bradycardia -> body attempts to reduce afterload above the level of the injury (hypotension)

MOA for pruritis caused by opioids

stimulation of opioid receptors in the trigeminal nucleus. More common in pregnant women

What is the physiologic mechanism for opioid induced miosis

stimulation of the Edinger-Westphal nucleus which increases PNS tone to the oculomotor nerve and constricts the pupil

choledocholithiasis

stones in the common bile duct ERCP

ion trapping

when drugs change body compartments, they may become ionized and trapped in the new environment ex. maternal alkalosis (drug in non-ionized) -> drug passes to fetus -> fetus is more acidic & drug becomes ionized -> cannot pass back out (trapped) -as the drug becomes ionized in the fetus it drives a concentration gradient for more non-ionized drug to cross over making the situation worse

Monroe-Kellie Doctrine

when one content in the skull increases, another must decrease to compensate and maintain normal ICP

Plateau pressure which increases risk for barotrauma

when plateau pressure exceeds 35cm/H2O

When is surgical repair of AAA recommeded

when the diameter exceeds 5.5cm or if it grows 0.6-0.8cm/year

Heart failure

when the hearts pumping action fails to satisfy metabolic demands -defect in the heart's ability to fill and/or empty

S/S of subarachnoid hemorrhage

worst HA of their life N/V photophobia fever When blood blocks CSF, ICP increases

Hyperadrenocorticism clinical findings

wt gain hyperglycemia Muscle & bone weakness weakened immune system Hirutism moon face Diagnostics: Dexamethasone suppression test, Glucose tolerance, urinary cortisol, Adrenal CT/MRI

T6 dermatome

xiphoid process

Antidromic AVRT

~10% of cases Atrium -> Accessory pathway -> ventricle -> AV node -> Atrium Wide QRS more dangerous version Tx: Block conduction at the accessory pathway (DO NOT block conduction at the AV node) Procainamide, Cardioversion

Estimation of how much FGF is needed to prevent rebreathing in Mapleson Circuit

~2.5 times patient's minute ventilation Exception: Mapleson A requires 20L/min to avoid rebreathing during controlled ventilation

Where should the tip of an esophageal US be positioned

~35cm from incisors T5-T6 at the 3rd intercostal junction

OB recipe - epidural

• 0.2% Ropivacaine with 2mcg/mL fentanyl • 8-10mL/hour • 4mL bolus every 30 min • PCEA (pt controlled epidural analgesia) vs Bolus delivery Modalities

Anesthetic mgmt Eaton-Lambert Syndrome

Sensitive to Succ and NDNMBs - reduce doses Volatile anesthetics are usually enough w/out NMBs Reversal w/ anticholinesterases may be inadequate despite proper dosing High risk for postop respiratory failure strong correlation to small cell carcinoma (oat cell carcinoma)

T4 innervation

Sensory: nipple line Moto/Autonomic: T1-T4 cardiac accelerator fibers

Trigeminal (Cranial Nerve V)

Sensory: nose to anterior 2/3 of tongue V1 Opthamalic: Nares and anterior 1/3 of nasal septum V2 Maxillary: Turbinates and septum V3 Mandibular: Anterior 2/3 of tongue Motor: 0

Glossopharyngeal (Cranial Nerve IX)

Sensory: soft palate to anterior epiglottis Soft palate Oropharynx Tonsils Posterior 1/3 of tongue Vallecula Anterior side of epiglottis (afferent gag reflex) Motor: 0

What is the function of the BBB

Separates the CSF from the plasma -via tight junctions -does not have carrier proteins -poorly developed in neonates

Disease states that increase SVO2

Sepsis Nipride toxicity L -> R cardiac shunt

Ondansetron (Zofran)

Serotonin (5-HT3) antagonists. Gold standard A/e: headache, EPSs. Prolonged QT (same as Droperidol but no BBW so you don't have to do an ECG). Adult: 4-8mg IV, Child: 50-100mcg/kg (max 4mg) More effective for PONV that PDNV because duration is 4-6h. Administer at end of procedure.

IABP contraindications

Severe aortic insufficiency Descending aorta disease Severe PVD Sepsis

% of hepatic biotransformation per agent

Sevo: 2% Iso: 0.2% Des: 0.02% N2O: 0.004%

Causes of Motion artifact

Shivering Patient movement Patient positioning Electrocautery Venous pulsation

WPW EKG findings

Short PR interval (<0.12sec) delta wave widened QRS complex possible t wave inversion

Hypercalcemia on EKG

Short QT interval

Bupivacaine (Marcaine) - epidural

• 0.5% if needing surgical anesthesia • 0.25% if needing analgesia • This is a strong ANALGESIC block • 0.125% if needing Sensory > Motor block • Post op pain relief • Run 5-10 mL/hour

Treatment for pediatric cardiac arrest after Succ (hyperkalemia)

Stabilize myocardium: CaCl 20mg/kg or Ca gluconate 60mg/kg Shift K+ back into cell: 10% dextrose 0.3-0.5g/kg, insulin 1 u/5g dextrose, bicarb 1-2 mmol/kg, hyperventilation, albuterol neb. Enhance K elimination: 1-2mg/kg lasix, volume resuscitation, hemodialiysis, hemofiltration

Cerebral Oximetry

Utilizes near infrared spectroscopy to measure cerebral oxygenation -measures venous oxygen saturation -detects regional oxygenation (not global) -noninvasive, continuous data

What does a wide PaCO2 to EtCO2 gradient indicate

V/Q mismatch equipment malfunction often caused by increased dead space (hypotension, reduced CO, PE)

Late respiratory complications of scoliosis

V/Q mismatching Hypoxemia Hypercarbia (signs of impending failure) Pulmonary hypertension reduced response to hypercapnia Cor pulmonale Cardiorespiratory failure

List the 3 branches of CN V and function

V1: Opthamalic V2: Maxillary V3: Mandibular Somatic sensation to face, Somatic sensation to anterior 2/3 of tongue, muscles of mastication

Best leads to monitor for ST changes (Normal or no EKG on file)

V3 > V4 > V5 > III > avf for abnormal EKG, monitor the areas most at risk of ishcemia

femoral triangle

VAN from lateral to medial = vein, artery, nerve NAVL from medial to lateral = nerve, artery, vein, lymph

Narrowest part of adult airway

Vocal cords Cylinder shaped

isoflurane

Volatile agent of choice, has the least effect on heart and hepatic blood flow.

3 factors that disrupt autoregulation

Volatile anesthetics Head trauma Intracranial tumor

Drugs that potentiate NMB's

Volatile anesthetics>N20>Propofol Antibiotics (-ycins) Antidysrhythmics: Verapamil, Amlodipine, Lidocaine, Quinidine Local Anesthetics Furosemide Dantrolene Cyclosporine Tamoxifen Hypothermia and female gender also potentiate NMB's

Voltage, Current, Impedance

Voltage: Driving Pressure Current: Flow Impedance: Resistance

Primary determinant of epidural spread

Volume

Primary determinant of spread in epidural anesthesia

Volume

Non-controllable factors that effect spread for spinal

Volume of CSF Density of CSF Age

Mu receptors

analgesia, respiratory depression euphoria, sedation, physical dependence Prolactin release, mild hypothermia miosis, Constipation (marked), urinary retention, bradycardia, pruritus Skeletal muscle rigidity ↑biliary pressure, ↓peristalsis Agonists: Endorphins, morphine, syth opioids Antagonists: Naloxone, naltrexone, nalmefene

filum terminale

anchors spinal cord to coccyx extends from conus medullaris to the coccyx

What pulse ox cannot monitor

anemia ventilation Bronchial intubation

Surgical treatment for SAH

aneurysm clipping or endovascular coiling surgical repair should take place 24-48 hours after initial bleed

Unstable angina

angina at rest new onset angina (<2 months) Increasing symptoms (intensity, freq, duration) duration exceeds 30min

Divisions

anterior x 3 posterior x 3

Naso pharyngeal airway contraindications

anti-coagulation Le Fort 2 or 3 fracture Basilar skull fracture CSF rhinorrhea Raccoon eyes Periorbital edema

Anterior spinal artery syndrome

aortic clamp placed above Adamkiewicz causes ischemia to the lower part of the anterior spinal cord

Carbamezapine s/e

aplastic anemia Thrombocytopenia Liver dysfunction Leukopenia ADH like effect - hyponatremia

The mean electrical vector tends to point away from

area of myocardial infarction (dead tissue)

Sciatic nerve block

arises from L4-5 & S1-3 Useful for surgeries on the back of the thigh, lower leg, ankle, and foot

intercostal brachial nerve

arises from T2 = not covered in a brachial plexus block Field block is required to anesthetize this nerve = block may help awake pt tolerate UE tourniquet

body movement associated w/ perctoralis twitch response

arm adduction

F(a)

arterial gas concentration = affected by: -ventilation/perfusion mismatching

Guillain-Barre syndrome

ascending paralysis/muscle weakness that is preceded by influenza like illness

Line Isolation Monitor

assesses the integrity of the ungrounded power in the OR -Primary purpose is to alert the OR staff of the first fault -The monitor itself does protect against shock, it is just a warning -it it alarms the last piece of equipment that was plugged in should be unplugged -The LIM will alarm when 2-5 mA of leak current is detected -All electric devices leak a little current, when the sum exceeds 2-5 mA the alarm will sound - but in the case there is no risk of shock

uses for rigid bronchoscopy:

assessment of massive hemoptysis, laser surgery, bronchodilation, and stent placement

Metabolites of Sevo

Not metabolized to TFA, but does result in the liberation of inorganic fluoride ions. B/c it undergoes the highest amount of hepatic metabolism of modern agents there is a theoretical possibility that it could result in high-output renal failure (unresponsive to vasopressin) s/s: polyuria, hypernatremia, hyperosmolarity, ↑Cr, inability to concentrate urine

Increases as the airway bifurcates

Number of airways cross sectional area muscular layer

Vessel rich group (VRG)

brain, heart, kidneys, liver, and endocrine glands -b/c of the high CO delivered to these organs they receive the most anesthetic agent during induction and are the first to equilibrate VRG > Muscle > Fat Fat acts as a sink for fat-soluble agents

osteogenesis imperfecta

brittle bone disease = connective tissue d/o Possible difficult airway = c-spine precautions, cervical range of motion Kyphoscoliosis -> restrictive lung dx -> V/Q mismatch Blue sclera Increased serum thyroxine

membrane oxygenator v bubble oxygenator

bubble oxygenator uses a blood-gas interface rather than a membrane so there is a greater chance of an air embolism

Accessory pathways

bypass the normal electrical conduction route

CMRO2 is ___________ to cerebral blood flow

coupled = the higher the need for oxygen, the more blood will be there to satisfy the need

benefit to using opioids with LA

creates a denser block

Narrowest part of the pediatric airway

cricoid cartilage Funnel shaped

Causes of pancreatic pain

Obstruction and distention of pancreatic ducts Edema, with stretching of pancreatic capsule Edematous duodenal obstruction Biliary tract obstruction Inflammatory exudates, blood and enzymes in the retroperitoneum Chemical peritonitis Major enzymes: Trypsin, Enterokinase, Bile acids

Subclavian steal syndrome

Occlusion of subclavian or innominate artery proximal to the vertebral artery (usually on left side) -results in a reversal of flow where blood that normally would have gone to the brain goes toward the ipsilateral subclavian artery S/Sx → arm claudication, syncope (DROP ATTACKS), vertigo, nausea, confusion, arm ischemia, weak pusle

Paresthesia

Off midline - you're bumping into the nerves • During Needle/Catheter Advancement • During Medication Administration • Can cause permanent nerve injury/death

Lithotripsy and PPM's

Ok - beam should be directed away from the pulse generator

Factors w/ lower risk of PDPH

Older age Male Non-cutting tip needle Smaller diameter needle Fluid for LOR syringe Needle parallel to long axis of meninges Continuous spinal catheter (if placed after wet tap)

Calcium Channel Blockers

dihydropyridines = -dipine MOA: targets vascular smooth muscle (mostly) ↓ vascular intracellular Ca++ -> vasodilation, ↓SVR Non-dihydropyridines: verapamil & diltiazem MOA: targets myocardium (mostly) ↓inotropy, chronotropy, dromotropy, SVR

myasthenia gravis s/s

diplopia, ptosis (early signs) Bulbar muscle weakness (muscles of mouth & throat) -> dysphagia, dysarthria, and difficulty handling saliva DOE Proximal muscle weakness

arterial cerebral circulation

divided into anterior and posterior -> converge at the circle of Willis

Haloperidol (Haldol)

dopamine antagonist Dose: 1-2mg IV A/e: sedation, EPS, QT prolongation

Metoclopramide (Reglan)

dopamine antagonist Dose: 10-20mg IV Contraindicated in pt's w/ gastric obstruction d/t prokinetic effects

Prochlorperazine (Compazine)

dopamine antagonist Dose: 10mg IV Sedation prominent

Droperidol (Inapsine)

dopamine antagonists. Dose: 0.625-1.25mg IV BBW: QT prolongation - must do ECG b/f admin - limits usefulness. Contraindicated in parkinson's pt's

Where do sensory neurons enter the spinal cord?

dorsal root

Stimulation of the common peroneal nerve results in?

dorsiflexion and eversion TIPPED

Other factors that affect epidural spread

dose injection site/level elderly pregnancy

How do halogenated agents effect cardiac conduction

dose dependent fashion ↓ SA node automaticity ↓ conduction velocity through the AV node, bundle -> purkinje system ↑ duration of repolarization by impairing K+outflow - prolongs QT Altered baroreceptor function

potency

dose required to achieve a given clinical effect -x-axis of the dose response curve -ED50 and ED90 are measures of potency

Naloxone

dose: 1-4mcg/kg (give slowly to prevent overshoot) duration: 30-45min (short) metabolism: liver (significant first pass metabolism) crosses the placenta - (neonatal withdrawal)

Tuffier's Line

drawn across the iliac crest that crosses the body of L4 or L4-L5 interspace. * This is a helpful landmark for the placement of spinal or epidural anesthetics.

Increased risk for postop mechanical ventilation w/ myasthenia gravis

duration > 6 years Daily pyridostigmine > 750mg/day Vital capacity < 2.5L COPD Median sternotomy > transcervical approach

Factors that have no effect on PDPH

early ambulation Continuous spinal catheter (if placed after spinal block)

Factors that do not increase the risk of TNS

early ambulation LA concentration Baricity glucose concentration

Opioid withdrawal s/s

early: diaphoresis, insomnia, restlessness late: abdominal cramping, n/v withdrawal timing is based on drug half life

Infraclavicular indications and landmarks

elbow, forearm, and hand NOT above elbow Landmarks: Coracoid process, clavicle, Axillary artery and vein

Why is the QRS wide during V pacing

electrical signal delivered below the AV node

Amygdala

emotion appetite responds to pain and stressors

Low-risk procedures for cardiac morbidity and mortality (<1% risk) - per AHA guidelines

endoscopic procedures cataracts Superficial procedures Breast surgery Ambulatory procedures

endogenous opioid peptides

enkephalins, endorphins, dynorphins You can't synthesize these b/c they don't reach their target tissues and cause anaphylaxis

First order neuron (Anterolateral)

enters through dorsal root ganglion Cell body in the dorsal root ganglion Ascends or descends 1-3 levels on the ipsilateral side via Lissauer tract b/f synapsing with the 2nd order neuron Synapses with the 2nd order neuron in the dorsal horn laminae I, IV, V, VI

Metabolism (biotransformation)

enzymatic process of altering the chemical structure of a molecule -Primary role is to change a lipid soluble molecule into water soluble

Acetyltransferase

enzyme that catalyzes Acetyl CoA and choline

EKG 12 lead

Bipolar leads: I, II, III Limb leads: aVR, aVL, aVF Precordial leads: V1, V2, V3, V4, V5, V6

Correct BP cuff bladder size

Bladder length 80% of extremity circumference Bladder width 40% of extremity circumference

Cause of neuraxial induced bradycardia

Blockade of preganglionic cardioaccelerator fibers • Effect of unopposed vagal tone • The Heart Rate is slowed Unloading of ventricular mechanoreceptors (ie less ventricular filling) -> Bezold-Jarisch reflex Unloading of stretch receptors in the SA node (atrium) -> Bainbridge Reflex

Pancuronium CV effects

Blocks Cardiac M2 receptors Vagolytic -> tachycardia Stimulates the release of catecholamines and inhibits catecholamine reuptake

Carbamazepine MOA, metabolism

Blocks voltage gated Na+ channels Membrane stabilizer Hepatic metabolism Hepatic enzyme induction -> resistant to nondepolarizers Also useful for trigeminal neuralgia

Phenytoin MOA, metabolism

Blocks voltage gated Na+ channels Membrane stabilizer Hepatic metabolism Hepatic enzyme induction -> resistant to nondepolarizers Zero order kinetics

Hemodynamic effect of Sevo

0 HR ↓BP ↓/0 CO ↓SVR (least of the halogenated agents)

SA & AV node conduction speed

0.02-0.1m/sec (slow)

P wave

0.08 - 0.12 sec Amplitude < 2.5mm Prolonged w/ 1st degree block

PR Interval

0.12-0.20 sec Pericarditis -> PR interval depression

Ropivacaine - epidural

0.2% - Analgesic Block

Myocardial muscle cells conduction speed

0.3-1m/sec (intermediate)

Drugs to avoid w/ Antidromic AVRT

Adenosine Digoxin CCB BB Lidocaine

What does a pulse oximeter measure?

Hemoglobin saturation Heart rate Fluid responsiveness (pulse pressure variation)

Classic presentation of pulmonary artery rupture

Hemoptysis

innervates the laryngeal mucosa below the level of the cords

Recurrent laryngeal nerve (X)

Where is the positive electrode in Lead II

Red lead

Wavelength of deoxygenated Hgb

Red light (660nm)

What does inflation of IABP correlate to?

diacrotic notch -augmented diastole should be higher than unassisted systole

C3-5 myotome

diaphragmatic muscle

What is another way of saying ventricular compliance

diastolic pressure-volume relationship

Epidural needles

differ by angle of tip Crawford = 0 Hustead = 15 Tuohy = 30

biliary pressure

opioid increase billiary pressure d/t constriction of sphincters. Treatment:

injury above the level of decussation in the medulla

spastic paralysis on the contralateral side of the body

Telangiectasia

spider veins in CREST syndrome can cause mucosal bleeding

MAC BAR

"Blunt Autonomic Response" = alveolar concentration of anesthetic that blunts the autonomic response to noxious stimuli. Approximately 1.5 x MAC

Cricothyroid muscle

"Cords tense" -Tense vocal cords, elongate Tuning fork - key player in larygospasm reflex The only muscle that tenses/elongates the cords Innervation: SLN (external)

Lateral cricoarytenoid muscles

"Lets close airway" "Let's come together Adducts (narrows glottis) Innervation: RLN

Posterior Cricoarytenoid muscle

"Please come apart" Abducts Innervation: RLN

Small underdeveloped mandible

"Please get that chin" Pierre-Robin Goldenhar Treacher Collins Cri du Chat

Thyroarytenoid muscle

"They relax" -Shorten (relaxes the vocal cords Adducts (Narrows glottis) Innervation: RLN

When is awareness most likely to occur during CABG surgery with CPB?

#1: sternotomy #2: rewarming

Resistance

(Airway Pressure - Alveolar Pressure)/Gas Flow Rate

Naloxone side effects

(Effects of reversing the opioid -> pain -> SNS activating) SNS stimulation: tachycardia, HTN, dysrhythmias Neurological: neurogenic pulmonary edema, tremors/seizures, aggressive/combative Gastrointestinal: nausea/vomiting sudden death

Respiratory Considerations w/ DMD patients

-Kyphoscoliosis (restrictive lung disease) -> ↓pulmonary reserve -> ↑secretions & risk for pneumonia -Respiratory muscle weakness

Spleen functions

-Blood filtering -Immune processing of foreign antigens -Hematopoiesis in fetus -abnormal blood cells (sickle-cell disease and spherocytosis) are filtered and removed by macrophages -Old RBCs (>120 days) removed -Minor role in platelet storage -production of specific antibody IgM- facilitated in white pulp

Ulnar Nerve wrist block

Anatomic landmarks: ulnar styloid, ulnar pulse, flexor carpi ulnaris tendon Inject 3-5mL medial to and below the flexor carpi ulnaris tendon

Syndromes w/ large tongue

(big tongue) Beckwith syndrome Trisomy 21

Opioid CV effects

-Bradycardia -Blood pressure: minimal effects in healthy pts (synergistic with benzos) -↓BP with Morphine and Meperidine (d/t histamine) -Dose dependent vasodilation -Baroreceptor reflex not affected -Myocardial contractility not affected

High Extraction Drugs

(first order metabolism: liver first!) - oral dose must be adjusted up Fentanyl Sufentanil Morphine Meperidine Naloxone Ketamine Propofol Lidocaine Bupivicaine Metoprolol propranolol Alprenolol Nifedipine Diltiazem Verapamil

Kawasaki disease

(inflammation of blood vessels (strawberry tongue) causes coronary artery aneurysms. -primarily children -risk for myocardial ischemia Also called Mucocutaneous lymph node syndrome

Mu 1 receptor

**Analgesia, bradycardia euphoria miosis hypothermia urinary retention

Supraclavicular complications

**Pneumo (highest of all the blocks) - cupola of the lung is just medial to the first rib Horner's syndrome Subclavian artery injection (aspirate!)

Infraclavicular complications

**Venous inj (higher than supraclav) pnemo (lower than supraclav) discomfort rarely blocks the phrenic nerve

Mu 2 receptor

*Analgesia (spinal only) *Respiratory depression *Constipation *Physical Dependence

Mu 3 receptor

*Immune suppression

Margin of error for pulse ox

+/- 2-3%

normal mean electrical vector

-30 to +90

Left axis deviation

-30 to -90

Carotid cross clamp

-After carotid is clamped CBF relies on circle of willis for collateral flow -During cross clamp maintain or increase BP (phenylephrine, reduce depth) -After cross clamp reduce SBP < 145 (HTN -> reperfusion injury -> cerebral edema) vasodilators or labetalol

Pancreatic secretions

-Clear, colorless liquid with a pH of 8.3 -Acinar cells -98% of the organ, synthesize and secrete digestive enzymes and bicarbonate -principal fxn is to adjust the pH of duodenal contents to promote optimal activity of pancreatic enzymes

Advantages of the circle system

-Consistent inspired gas concentrations -Maintains heat and humidity -Low resistance (Not as low as Mapleson circuit) -Can be used as semi-open, semi-closed, closed) -Minimizes OR pollution

Cardiac Considerations w/ DMD patients

-Degeneration of cardiac muscle: ↓contractility, papillary muscle dysfxn, Mitral regurg, cardiomyopathy, CHF -s/s of cardiomyopathy: tachycardia, JVD, S3/S4 gallop, displacement of point of maximal impulse -gold standard for evaluation is echo, can also do cardiac MRI

Factors that enhance release of carcinoid hormones

-Direct stimulation -Beta adrenergic stimulation

Key considerations for CEA

-Head rotation, extension, or flexion can decrease cerebral perfusion -Hyperglycemia increases risk of stroke - treat b/f surgery -Mild hypocarbia to prevent hyper carbia related dilation of cerebral vessels which can cause a steal phenomenon w/ blocked vessels which are maximally dilated

CEA postoperative considerations

-Hematoma = airway emergency - cric or trach (if surgeon unavailable, remove sutures to decompress wound) -RLN injury - unilateral = hoarseness -Hemodynamic instability = due to exposure of baroreceptors (HoTN and HTN possible but HTN more common) -Carotid denervation = reduces ventilatory response to hypoxia (why we don't do bilateral CEA's)

Avoid w/ liver dx

-Hypotension -Excessive sympathetic activation -High mean airway pressures during controlled ventilation (decreased venous outflow=HTN)

Causes of ↑ SNS outflow which produces hepatic arterial vasoconstriction

-Hypotension -Hypovolemia -Hypoxia -Hypercarbia (hepatic vasoconstriction) -Light anesthesia Abdominal surgery: most profound etiologic factor that results in decreased hepatic flow

Treatment of succ induced hyperkalemia

-IV CaCl -Hyperventilation -Glucose & Insulin

Liver dx med consideration

-Iso has the least effect on hepatic bld flow -Fentanyl is the opioid of choice -Avoid morphine sphincter of Oddi spasm & histamine release)

Causes of increased frequency on EEG

-Mild hypercarbia -Early hypoxia -seizures -ketamine -N2O -light anesthesia

Disadvantages of the circle system

-Multiple places where disconnections can occur -Less portable than non-rebreathing circuits -Unidirectional valve malfunction (Stuck open: rebreathing, Stuck closed: airway obstruction) -Increased dead space (Vd ends at the Y)

Methods to improve SpO2 signal

-Performance of a digital block -warming the extremity -Protecting the extremity from ambient light -Vasodilating cream -Administer an arterial vasodilator

Treatment for Systolic HF

-Reduce preload: Diuretics -Reduce afterload; Vasodilators: ACE-i's, ARBs, NTG, Nitroprusside -Increase contractility; Inotropes: Dobutamine, Dopamine, Milrinone -↑HR - usually high d/t increased SNS tone, but may need high rate to preserve CO in light of ↓EF

Hormones secreted from carcinoid tumors

-Serotonin -Bradykinin -Tachykinins -Prostaglandins -ACTH -Histamine

Determinants of delivery to the alveoli (FI)

-Setting on the vaporizer -Time constant of the delivery system -Anatomic dead space -Alveolar ventilation -Functional residual capacity -FGF

Opioid neurologic effects

-Shifts CO2 response curve to the right and reduces ventilatory response to CO2 -↓RR, ↑Vt (↑PaCO2 increases ICP) -Miosis -Minimal effect on evoked potentials -Chemoreceptor trigger zone stimulation

Determinants of Removal from the alveoli (Uptake)

-Solubility of anesthetic in the blood -CO -Partial pressure gradient between the alveolar gas and the mixed venous blood

Differences in morphine's affect on women

-greater analgesic potency -slower onset of action -longer duration of action -lower postoperative opioid consumption

LAST protocol

-Stop injecting -Get help (Call for LAST rescue kit) -Consider lipid emulsion therapy at first sign -May need ECMO - alert nearest facility -Airway: 100% O2, avoid hypoventilation -Control seizures: benzos, avoid lg doses of propofol (hemodynamic instability) -Limit individual epi doses < 1mcg/kg -Treat hypotension and bradycardia (avoid vasopressin, calcium channel blockers, beta blockers, and other LA's) -CPR/ACLS if necessary

Why Succinycholine does not cause fade

-Succ is a Nn agonist so it continually stimulates the release of ACh. The continued binding of ACh to the postsynaptic receptors leads to initial fasciculation and then paralysis due to inability of channels to close leading to a state of absolute refractory.

Hepatitis

-alcohol most common cause (hep C is 2nd) -dx: liver enzymes, bili, liver inflammation -s/s: jaundice, fatigue, thrombocytopenia, glomerulonephritis, neuropathy, arthritis, myocarditis prolonged PT, decreased albumin

Cerebral perfusion monitors

-awake pt -EEG -NIRS (at risk when drops 25% or more from baseline) -Transcranial doppler: measures blood flow velocity in middle cerebral artery (most common location for emboli) -SSEP: sensory pathways only

Changes in protein binding result from

-change in protein concentration -competition for binding sites on the protein

Things that affect EtCO2

-changes in CO2 production -impaired pulmonary perfusion -impaired ventilation -equipment malfunctions

Second order neuron (Dorsal)

-crosses to contralateral side in the medulla, then ascends to the thalamus via the medial lemniscus -joined by the trigeminal nerve which provides sensation to the head -synapses with the 3rd order neuron in the thalamus - ventrobasal complex

neurotransmission is reduced by:

-decreased cAMP -decreased Ca2+ conductance -decreased K+ conductance

Cerebral vasospasm

-delayed contraction of cerebral arteries -can lead to cerebral infarction -can be caused with free hgb in contact with outside of cerebral arteries (ie. blood where its not supposed to be) -most common 4-9 days following SAH

Anesthetic mgmt of cirrohsis

-depressed response to inotropes and vasopressors -alcoholic cardiomyopathy -HF -Preserve hepatic blood flow (volatile anesthetics decrease hepatic bld flow) -Maintain normocapnia -Avoid peep

GA for CEA

-does not require pt coorperation -controlled airway -Ability to administer agents that control cerebral metabolic rate -May require cerebral blood flow monitors

How are inhaled anesthetics eliminated from the body?

-elimination from the alveoli (exhalation is primary) -Hepatic biotransformation (P450) -Percutaneous loss

3 categories of inhaled anesthetics

-ethers -alkanes -gases

CV changes w/ liver dx

-hyperdynamic circulation=↑CO, ↓SVR, ↑RAAS activation, ↓response to vasopressors, diastolic dysfxn, ↓blood viscousity, anemia -portal HTN=↑hepatic vascular reisistance -> ↑back flow (esophageal varisces, splenomegaly)-> arteriovenous shunting d/t extensive systemic collateral vessels -Ascites (↓oncotic pressure, ↓protein binding) -alcoholic cardiomyopathy -preop HF

Beta blockers

-lol beta-1 selective: Acebutolol, atenolol, bispropolol, esmolol, metropolol non-selective: nadolol, pindolol, propranolol, sotalol, timolol mixed alpha & beta: carvedilol, labetalol MOA: ↓inotropy, chronotropy, dromotropy, renin release propranolol doesn't just block it causes the opposite effect (↓cAMP)

Pruiritis

-more common in obstetric patients -caused by opioid receptors in the trigeminal nucleus (NOT mast cell degranulation) -treat w/ naloxone (benadryl will not treat this, but the sedative effect may be helpful)

TNS - Transient Neurological Symptoms causes

-patient positioning -stretching of the sciatic nerve -mayofascial strain -muscle spasm

Artery of Adamkiewicz

-perfuses the anterior spinal cord in the thoracolumbar region (thoracolumbar region is totally reliant on radicular arteries for perfusion -Originates on the left for most people b/w T11-T12

Bile

-produced by hepatocytes -drained by canaliculi into bile ducts ->common hepatic duct

Contribution of inflammation to pain

-reduce threshold to pain stimulus (allodynia) -increased response to pain stimulus (hyperalgesia)

How does application of aortic cross clamp cause central hypervolemia

-reducing venous capacity -shifts greater portion of the blood proximal to the cross clamp -venous return increases (smaller venous pool)

How does removal of cross clamp cause hypovolemia

-restores venous capaciy -shift greater proportion of blood to the lower body -Capillary leak contributes to intravascular loss -Venous return decreases (coronary perfusion will decrease of because of decreased venous return)

Augmented gas inflow

-the concentrating effect temporarily reduces the volume of the alveoli -on the second breath, the concentrating effect causes an increased inflow of tracheal gas containing anesthetic agent to replace the lost alveolar volume. This augments the increased FA. This is a very short lived phenomenon as alveolar volume is quickly restored.

The amount of ionization depends on what 2 things

-the pH of the solution -the pKa of the drug When the pka of the drug and the pH are the same 50% of the drug will be ionized and 50% will be nonionized

What is the uptake of anesthetics to the tissue dependent on?

-tissue blood flow (delivery method) -Solubility of the anesthetic in the tissue -Arterial blood: tissue partial pressure gradient

The concentrating effect

-when a pt is breathing room air, nitrogen is the primary gas in the alveoli -N2O is 34x's more soluble in the blood than nitrogen - when N2O is delivered to the lung it passes from the alveoli into the blood at a much faster rate than nitrogen traveling from the blood into the alveoli. This causes the alveoli to shrink. This increases the relative concentration of N2O in the alveoli. This increase the FA/FI rate of rise. -This is why N2O has a faster rate of rise than Des even though Des is the least soluble

alpha 1 antagonists

-zosin & phenoxybenzamine and phentolamine (a-1 & 2) MOA: ↓ vascular intracellular Ca++ -> vasodilation, ↓SVR

MODIFIED BROMAGE SCALE

0 - No motor block 1 - inability to raise extended leg; able to move knees and feet 2 - inability to raise extended leg and move knee; able to move feet 3 - Complete block of motor limb

5 Phases in a ventricular action potential

0 = Rapid depolarization (QRS) 1 = Initial repolarization (QRS) 2 = Plateau phase (QT) 3 = Final repolarization (T wave) 4 = Resting phase (T->QRS)

2 types of extrajunctional receptors (subunit makeup)

1- gamma subunit replaces epsilon subunit 2- 5 alpha subunits

Normal CVP

1-10 mmHg

bundle of His, bundle branches, Purkinje fibers conduction speed

1-4m/sec (fast)

Normal length of transient neurological symptoms (TNS)

1-7 days

2 factors that affect the rate of metabolism

1. concentration of drug at site of metabolism - influenced by blood flow to the site 2. intrinsic rate of metabolism - genetics, enzyme induction, and enzyme inhibition

How do VIA alter the respiratory pattern?

1. decrease tidal volume 2. increase respiratory rate 3. decrease minute ventilation (the compensatory increase in RR not enough to offset the decrease in Vt)

Factors the affect or modulate conduction velocity

1. ANS tone 2. Hyperkalemia induced closure of fast Na+ channels 3. Ischemia 4. Acidosis 5. Antiarrhythmic drugs

Mechanism for presynaptic effects of reversal agents

1. AchE inhibitors can bind to the presynaptic receptor & increase the release of Ach 2. Inhibition of AchE near the presynaptic receptor increases the concentration of Ach available for binding the presynaptic receptor.

How do VIA cause hypercarbia?

1. Altering respiratory pattern 2. impairing the response to hypercarbia 3. impairing motor neuron output to upper airway and thoracic muscles

What are the 3 internodal tracts

1. Anterior internodal tract (Bachmann Bundle) 2. Middle internodal tract (Wenckebach tract) 3. Posterior internodal tract (Thorel tract)

Ways to predicts airway difficulty

1. Bag mask ventilation (BMV);(w/ or w/out jaw thrust maneuver) 2. Direct laryngoscopy (DL) and video laryngoscopy (VL) with tracheal intubation (TI) 3. Supraglottic airway ventilation (LMA) 4. Cricothyrotomy airway placement (e.g., needle or surgical) or tracheostomy Problems or indications of complexity with one or more of these four methods of providing ventilation would indicate a difficult airway.

Conditions that increase HR

1. Beta agonist 2. Pancuronium 3. Ketamine 4. Desflurance 5. Oxytocin 6. Light anesthesia 7. Histamine releasing drugs (morphine, meperidine, thiopental, atrucurium)

Conditions that increase contractility

1. Beta-agonists 2. Digoxin 3. Light anesthesia (SNS stimulation)

Pain augmentation

1. Central sensitization 2. Wind up

What are the 5 determinants of blood flow?

1. Cerebral metabolic rate for oxygen 2. Cerebral perfusion pressure 3. Venous Pressure 4. PaCO2 5. PaO2

Potential causes of primary HTN

1. Chronic vasoconstriction leading to activation of RAAS 2. SNS overactivity 3. Vasodilator deficiency 4. Vascular stiffness 5. Diet (sodium)

MH treatment acute phase

1. D/C triggering agent 2. Call for help, tell surgeon to end procedure 3. Hyperventilate pt w/ 100% O2, 10L/min (don't waste time changing soda lime) -Facilitates CO2 elimination -↑ O2 delivery -drives K+ into cells 4. Administer Dantrolene 5. Cool pt 6. Correct lactic acidosis (bicarb) 7. Treat hyperkalemia 8. Class I antiarrhythmics 9. Maintain UOP > 2ml/kg/h (mannitol, lasix, fluid) 10. Monitor coag panels for DIC (Late sign)

4 conditions that increase the risk of LVOT obstruction

1. Decreased pre-load 2. Decreased afterload 3. Increased heart rate 4. Increased contractility

Sequence of events for myocardial ischemia (mismatch between myocardial oxygen supply and demand

1. Diastolic dysfunction = decreased ventricular compliance 2. Systolic dysfunction = wall motion abnormalities - causes decreased ejection fraction (TEE detects this) 3. EKG changes = T wave inversion, ST depression (partial thickness injury), ST elevation (full thickness injury) 4. Clinical symptoms (not always present) = angina, diaphoresis, SOB 5. Myocardial infarction = results when oxygenation is not restored (supply and demand balance is not corrected) in a timely fashion. Leads to HF, cardiogenic shock, death

What nerves does the psoas compartment block target

1. femoral 2. obturator 3. lateral femoral cutaneous

Treatment of neurogenic shock

1. fluid resuscitation 2. atropine 3. vasopressor (norepi) No Succ (esp. 24 after time of injury)

Cerebral metabolic rate is dependent on

1. Electrical activity (60%) 2. Cellular homeostasis (40%) VIA only effect the electrical activity. Once an EEG is isoelectric they cannot suppress CMRO2 any further 1.5-2 MAC is needed to produce isoelectric state

3 ways to inhibit AchE

1. Electrostatic attachment -competitive inhibition: Edrophonium 2. Formation of carbamyl esters -competitive inhibition: Neostigmine, pyridostigmine, physostigmine 3. Phosphorylation -noncompetitive inhibition: organophosphates & echothiophate

How does AchE inhibitors increase concentration of Ach at the NMJ receptors

1. Enzyme inhibition 2. Presynaptic effects

Relative contraindications d/t HoTN caused by sympthectomy

1. Fixed valve lesions = severe AS, MS, hypertrophic cardiomyopathy 2. Full stomach can lead to N/V d/t HoTN

Opioid MOA

1. G protein activation= Inhibits adenylate cyclase -> decrease cAMP 2. ↑K+ conductance (channel open) ->out of cell (hyperpolarizing) 3. ↓ Ca++ conductance (channel closed) =INHIBITION OF NEUROTRANSMISSION 4. MAPK cascade activated -> prostaglandins and leukotrines

Types of blocks

1. Glossopharyngeal block: lingual branch, posterior 1/3 of tongue 2. Superior Laryngeal nerve block: supraglottic region 3. Transtracheal block:thru cricothyroid membrane

Myocardial oxygen supply is a function of:

1. HR 2. Aortic diastolic pressure 3. Coronary blood flow (CPP) 4. Oxygen content 5. Oxygen extraction

Most common hematologic complication of RA?

Anemia Platelet dysfunction is d/t NSAID use

6 risk factors for perioperative cardiac morbidity and mortality for non-cardiac procedures

1. High risk surgery 2. History of ischemic heart disease (unstable angina is highest risk) 3. CHF 4. Cerebral vascular disease 5. Diabetes Mellitus 6. Cr > 2mg/dL

Impairment of motor neuron output to upper airway and thoracic muscles

1. Impairment of airway dilator muscles - genioglossus or tensor palatine lead to airway obstruction (not airway smooth muscle - VIA are bronchodilators) 2. Impairment of pulmonary muscles ↓ FRC and the effectiveness of ventilation (muscles in the upper airway, diaphragm, intercostals)

What increases the risk of respiratory depression w/ neuraxial opioids

1. higher doses 2. co-administered sedatives 3. low lipid solubility 4. advances age 5. opioid naivety 6. increased intrathoracic pressure

Conditions w/ a link to MH

1. King Denborough syndrome 2. Central core disease 3. Multiminicore disease possible link w/ hypokalemic periodic paraylysis

Order for bier block tourniquet inflation

1. PIV in operative arm 2. elevate arm for 2 minutes 3. wrap w/ esmarch 4. Inflate distal cuff 5. Inflate proximal cuff 6. Deflate distal cuff 7. Remove esmarch 8. Inject LA

Hematologic changes w/ liver dx

Anemia (Acceptable hematocrit: 30%) Thrombocytopenia (Acceptable PLT is 100,000) Leukopenia Coagulation disorders Preservation of hepatic arterial bld flow is critical: portal venous blood flow is reduced

The big 4 side effect of neuraxial opioids

1. Pruitis 2. Respiratory depression 3. Urinary retention 4. N/V

3 causes of pacemaker failure

1. Pulse generator failure 2. Lead failure 3. Failure to capture

Factors that determine conduction velocity

1. RMP 2. Amplitude of the AP 3. Rate of change in membrane potential in phase 0

4 cardinal signs of Parkinson's

1. Resting "pill rolling" tremor 2. Rigidity (increased muscle tone) 3. Bradykinesia (slowed movement) 4. Postural instability - loss of balance w/ altered gait 2 of the 4 signs is diagnostic

Pain inhibition

1. Spinal neuron release Gaba or glycine 2. the descending pathway releases NE, 5-HT, endorphins

What 5 nerves does an ankle block anesthetize?

1. Superficial peroneal (Sciatic) 2. Sural (Sciatic) 3. Saphenous (Femoral) 4. Deep peroneal (Sciatic) 5. Tibial (Sciatic)

5 ligaments of the spinal column in order from superficial to deep

1. Supraspinous ligament 2. Interspinous ligament 3. ligamentum flavum 4. Posterior longitudinal ligament 5. Anterior longitudinal ligament

Consequences of increased intracellular calcium

1. Sustained muscle contraction 2. Accelerated metabolic rate and rapid depletion of ATP 3. Increased O2 consumption 4. Increased heat & CO2 production 5. Mixed respiratory and metabolic acidosis 6. Sarcolemma breaks down 7. Potassium and myoglobin leak into systemic circulation 8. Rigidity and sustained contraction

What 2 things does Vd assume

1. The drug distributes instantaneously 2. The drug is not subjected to biotransformation or elimination b'f it fully distributes

4 steps of the pain process

1. Transduction 2. Transmission 3. Modulation 4. Perception

6 conditions that decrease preload

1. Vasodilators 2. Neuraxial anesthesia 3. Hypovolemia 4. Postural changes (reverse T-berg) 5. PPV 6. Valsalva maneuver

3 conditions that decrease afterload

1. Vasodilators 2. Neuraxial anesthesia 3. Oxytocin

Order of CSF flow

1. choroid plexus 2. lateral ventricles 3. 3rd ventricle 4. Aqueduct of Sylvias 5. 4th ventricle 6. Foramen of Luschka 7. Foramen of Megendie 8. subarachnoid space + central canal -> superior sagittal sinus

4 sites of brain herniation

1. cingulate gyrus under the falx 2. tentorium cerebelli (transtentorial) 3. cerebellar tonsils through the foramen magnum 4. through the site of surgery or head trauma (ie an unnatural opening in the skull)

Relative contraindications to neuraxial anesthesia

1. coagulopathy: risk of hematoma, PLT < 100,000, PTT, aPTT, or bleeding time twice normal level 2. ↑ICP = change is CSF pressure 3. Sepsis 4. Infection at the puncture site 5. Hypovolemia = worsening of HoTN d/t sympathectomy 6. Scoliosis, arthritis, spinal fusion, osteoporosis (technical difficulty) 7. Difficult airway = complicates quickly converting to GA if block fails 8. Peripheral neuropathy = slow recovery, more susceptible to injury 9. Multiple sclerosis = epidural is safe but intrathecal may cause exacerbation (an NCE thing - not true in practice)

Order of recovery in differential blockade

1. motor 2. touch 3. pinprick (fast pain) 4. Temperature 5. pre-ganglionic sympathetic Anesthetized in the opposite order

myasthenia gravis postoperative concerns

1. sensitive to residual effect of nmb's 2. bulbar muscle weakness -> increased risk of pulmonary aspiration 3. possible postop mechanical ventilation

How to break a re-entry circuit

1. slowing conduction velocity through the circuit 2. Increasing the refractory period of the cells at the location of the unidirectional block

4 ways to ventilate during rigid bronchoscopy

1. spontaneous ventilation (w/ topical anesthesia) 2. Apneic ventilation (need to pre-oxygent & stop surgery intermittently to ventilate) 3. PPV (need a ventilating bronchoscope) 4. jet ventilation (use TIVA - entrainment of room air increases awareness)

Characteristics of lipophilic opioids

1. stays in CSF for a shorter period of time 2. minimal rostral spread -> narrower band of analgesia 3. Site of action: Substantia gelatinosa Rexed Lamina II & III & systemic 4. Onset is fast (5-10min) 5. Duration is shorter (2-4h) 6. more systemic absorption 7. Early (<6h) respiratory effects only 8. Low incidence of N/V & Pruritis

Characteristics of hydophilic opioids

1. stays in CSF longer 2. More extensive spread -> wide band of analgesia -> more rostral spread (toward brain) 3. Site of action: Substantia gelatinosa Rexed Lamina II & III 4. Onset is delayed (30-60min) 5. Duration is longer (6-24h) 6. Less systemic absorption 7. Early (<6h) and Late (>6h) respiratory effects 8. High incidence of N/V & Pruritis

Causes of upper airway obstruction

1. tongue: relaxation of genioglossus muscle 2. soft palate: relaxation of tensor palatine muscle 3. Epiglottis: relaxation of hyoid muscle Tongue and soft palette are the primary causes of obstruction

How do VIA impair the response to PaCO2?

1. ↓ response to CO2 -> shifts slope of the CO2 response curve down and to the right 2. increased apneic threshold (the PaCO2 at which a pt is stimulated to breathe - they stop breathing at a higher EtCO2) - ie if a patients apneic threshold is 50-52 its hard to get them back in breathing without getting them acidotic

Methods to reduce ICP

1. ↓Cerebral blood volume 2. ↓CSF 3. ↓cerebral edema 4. ↓cerebral mass

Specific gravity of CSF

1.002-1.009

Isobaric

1.004-1.009 Stays in the area, position does not affect block height. avg block height=low thoracic

RSI ETT size

1/2 size smaller than normal Use ETT with stylet to maximize chance of easy intubation

Bupivacaine (Marcaine) strength

1/8 - 1/4% - analgesia, no muscle weakness 1/2% - approaching anesthetic, starts to affect muscles 3/4% - total anesthetic, muscle weakness

Maximum allowable current leak in the OR

10 mcA (microamps)

Exception to baricity rule

10% procaine in water is hyperbaric b/c of the number of molecules in a 10% solution

How much blood is withdrawn for an epidural blood patch

10-20ml When the patient senses pressure in her legs, buttocks or back the injection is complete

Full Agonist Opioids

100% analgesia, the only ones we really give

Recommended delay times for surgery after PCI

Angioplasty w/out stent: 2-4 weeks Bare metal stent: 30 days (3 mo preferred) DES -stable ischemic disease 1st gen DES: 12 mo, 2nd gen DES: 6 mo -ACS: 12 mo minimum CABG: 6 weeks (3 mo preferred)

For every 10cm change in elevation, BP changes by For every inch change in elevation, BP changes by

10cm -> 7.4 mmHg 1 inch -> 2 mmHg

Boiling point

At high altitude a liquid will boil at a lower temp as a function of the reduction in atmospheric pressure

Valproic Acid (Depakote) MOA, metabolism

Blocks voltage gated Na+ channels Membrane stabilizer Hepatic metabolism Hepatic enzyme inhibition -> slows phenytoin metabolism

percent of cardiac output that goes to the brain

15%

Normal tracheal wall pressure

15-30 mmHg

Cormack and Lehane score

1: Full view of glottis 2: Partial view of glottis 3: Epiglottis only 4: No epiglottis or glottis

Dantrolene infusion dose on ICU

1mg/kg q 6h or 0.1-0.3mg/kg/h for 48-72h

C6 innervation

1st digit, thumb

Order of block

1st: Autonomic nerves (first) 2nd: Sensory fibers 3rd: Motor fibers (last) The highest level will be autonomic nerves (2-6 dermatomes higher than sensory) sensory will be blocked at a higher level than motor fibers (2 dermatomes higher than motor)

For an electrical shock to occur in the OR there must be

2 faults in the system 1. After the first fault, the OR power supply becomes grounded 2. After 2nd fault, the circuit is complete and electric shock occurs

Spinal cord circulation

2 posterior spinal arteries 1 anterior spinal artery 6-8 radicular arteries

spinal cord circulation

2 posterior spinal arteries 1 anterior spinal artery 6-8 radicular arteries

HTN diagnosis

2 separate measurements taken at least 2 weeks apart Elevated: 120-129/<80 HTN stage 1: 130-139/80-90 HTN stage 2: >140/>90 Hypertensive crisis: >180/>120

presynaptic release of Ach

2 supplies of Ach available for release -Ach available for immediate release -Ach that must be mobilized b/f release = presynaptic binding of Ach causes Ca++ channels to open and increased intracellular Ca++ which destabilizes the proteins that hold the Ach vesicles in places allowing for exocytosis

Order of duration (fast to slow) for epidural

2-Chloroprocaine 3%: 45-60min, epi: 60-90 Lidocaine 2%: 80-120min, epi: 120-180 Mepivacaine 2%: 90-140min, epi: 140-200 Etidocaine 1%: 120-200min, epi: 150-225 Ropivacaine 0.75-1%: 140-180min, epi: 150-200 Levobupivacaine 0.5-0.75%: 150-225min, epi: 150-240 Bupivacaine 0.5-0.75%: 165-225min, epi: 180-240

When to use an introducer

22g needle or smaller

Mask connector size ETT connector size

22mm internal diameter 15mm

ETT size range and pressure to check cuff leak for pediatric tubes

2.5 (neonate) - 8.5 (large adult) Cuff leak at 20-30 cmH2O

Max level of dosing for caudal pediatric anesthesia

2.5-3 mg/kg Any concentration is acceptable as long as max dose is not exceeded.

Dantrolene dose

2.5mg/kg IV, repeat q 5-10min if pt requires more than 20mg/kg reconsider diagnosis

Minimum amount of time the tourniquet needs to stay inflated w/ a bier block?

20 minutes

Metabolites of Halothane

20% of halothane is metabolized in the liver, which leads to a build up of TFA -> halothane hepatitis

BIS limitations

20-30 sec delay Hypothermia, electromyographic interference (↑muscle tone), & encephalopathy can impair BIS accuracy Less accurate in children

distance from incisors to carina

26cm incisors and larynx: 13cm distance from larynx to carina: 13cm

Correct position for IABP

2cm distal from left subclavian artery -more proximal positioning can cause occlusion of the common carotid or brachiocephalic arteries

C7 dermatome

2nd and 3rd digit

blood supply of nasal mucosa

3 arteries: Maxillary (sphenopalatine) Opthalamic Facial (Septal)

Time when incidence of catheter related infection increases

3 days

Within how many hours of an ischemic stroke must TPA be given

3 hours

Tx for Eaton-Lambert

3, 4- diaminopyridine (DAP) Anticholinesterases do not help

Average length from skin to the epidural space

3-4cm

How for to advance an epidural catheter (ie how much should be left in the epidural space)

3-5cm

optimal depth of catheter insertion in the epidural space

3-5cm

How much more soluble is N2O than nitrogen

34 x's Nitrogen blood:gas coefficient is 0.014. N2O blood: gas coefficient is 0.46

Hypobaric

<1 Lower density than CSF Ascends (don't usually use d/t risk of ascending block causing total spinal), but might use in jacknife b/c it would ascend to lower back

Drawback to CCO

30 second delay Value on the monitor is an average of the past 3-6min

Number of paired spinal nerves

31 -formed by a dorsal (posterior/sensory) and ventral (anterior/motor & autonomic)

LMA cuff pressure

<60 cmH2O (target is 40-60) Nerves at risk in overinflation: lingual, hypoglossal, recurrent laryngeal

Hyperbaric

>1.015 Greater density than CSF Sinks - In supine distributes to thoracic and sacral concavities. Why you lay pt's down after a spinal. avg block height= midthoracic

Sinus Tachycardia

>100 bpm usually caused by increased SA firing of SNS stimulation ↑myocardial O2 demand and ↓O2 supply Treat underlying cause or rate control w/ BB or CBB

Number of vertebrae

33 (7 cervical, 12 thoracic, 5 lumbar, 5 sacral, 4 coccygeal)

Portal hypertension

>20-30mmHg (normal is 7-10)

Normal EtCO2

35-40 mmHg

intracranial HTN

>20mmHg increased ICP decreased CPP and therefore decreases O2 delivery to the brain. This causes ischemia -> swelling -> decreased CPP -> more ischemia

What percentage of decline suggests cerebral ischemia

>25% from baseline Scalp hypoxia can falsely look like brain ischemia

What vital capacity correlates with requirement for postop ventilation

>40%

Gallstones

3F's: Fat, Female, 40 s/s: leukocytosis, fever, RUQ pain, pain is worse w/ inspiration (murphy's sign)

Necessary ACT for CPB

>400 seconds

Typical depth of cords

4-5cm

Minimum amount of time after MI b/f considering an elective surgery

4-6 weeks

Theta waves

4-7 cycles/sec General anesthesia and children during normal sleep

Cobb angle that is indication for surgery

40-50

Mortality for pediatric cardiac arrest after Succ

40-50% (avoid succ if at all possible)

Factors that reduce insulin secretion

Hypoglycemia Somatostatin Glucagon, cortisol, growth hormone (GH) α-Adrenergic Stimulation

Ace-i & AT-2 receptor blockers MOA

Inhibit Angiotensin II mediated vasoconstriction Inhibits aldosterone release

C8 dermatome

4th and 5th digit

Where is the phlebostatic axis?

4th intercostal space, mid anteroposterior level

How many half times does it take to reach steady state?

5

What LA is most associated with causing Cauda equina?

5% Lidocaine

Factors that increase the risk of cauda equina

5% lidocaine and spinal micro catheters (focus high concentrations of LA in one area)

CSF pressure

5-15 mmHg

Normal ICP

5-15 mmHg gold standard monitor is an intraventricular catheter

Dose for a bier block

50 mL of 0.5% lidocaine

Glossopharyngeal block

Needle inserted at the base of the palatoglossal arch. Aspiration Air: needle to deep Blood: redirect medially

Cobb angle with decreased pulmonary reserve

60

femoral block

Not a surgical block Nerve is within psoas major Blocked at the femoral triangle

How much does CMRO2 decrease per 1 degree celcius

7% = decreasing CMRO2 makes the brain more tolerant of decreased blood flow (more immune to ischemia) EEG suppression occurs at 18-20 degrees

Fire risk of N2O

Not flammable but does support combustion Fire risk during pneumoperioneum if cautery is used

Cobb angle wwhen respiratory s/s appear

70

What is pulse contour analysis a measure of

Preload responsiveness (ie is hypotension d/t hypovolemia) Changes in intrathoracic pressure during PPV can affect SV

Alpha waves

8-12 cycles/sec Awake but restful state, eyes closed

Recommendations for block placement: Cox inhibitors

Proceed if pt has normal clotting mechanism and is not on any other blood thinners

Volume of distribution (Vd)

Describes the relationship b/w a drug dose and the plasma concentration. -The greater the affinity of tissues for a drug relative to blood, the greater its volume of distribution

Alpha-2 agonists

Dexmedetomidine & Clonidine MOA: ↓SNS outflow

Neuraxial recommendations w/ NSAIDs

Proceed w/ neuraxial anesthesia if pt is not on any other blood thinners and has normal clotting mechanisms

Q wave

< 0.04 sec < 0.4-0.5 mm Consider MI if: -Amplitude greater than 1/3 the R wave -Duration > 0.04 sec -Depth > 1mm

Delta waves

< 4 cycles/sec General anesthesia, deep sleep, brain ischemia/injury

Cerebral Perfusion Pressure (CPP)

< 50mmHg = vessels are maximally dilated 50-150 = vessel diameter adjusts to keep CBF constant >150 = vessels are maximally constricted

Best timeframe for PCI outcome

< 90min

QRS complex

<0.10 sec If duration increased consider: BBB, LVH, ectopic beat, WPW

myastehnia gravis: _______________ to Roc/Vec

Sensitive b/c there is reduced Ach nicotinic receptors at the NMJ -reduce dose by 1/3-2/3

Dextrose vs water affect on baricity

Dextrose = Increases it (hyperbaric) -> more likely to sink Water = Decreases it (hypobaric) -> more likely to rise saline is generally isobaric

What causes a PDPH

A decrease in the amount of CSF in the subarachnoid space causing the medulla & brainstem to drop into the foramen magnum.

What can cause a burn with electrocautery

A fault in the return electrode Rather than traveling down the return cable, the current will find another place to exit the body (EKG patch, temp probe, metal elements of surgical table)

partition coefficient definition

A measure of how gas distributes between 2 compartments at equilibrium is reached

racemic mixture

A mixture that contains equal amounts of the (+) and (-) enantiomers. Examples: ketamine, thiopental, methohexital, Iso, Des, Mepivicaine, Prilocaine, bupivacaine, morphine, methadone, ibuprofen, ketorolac

What is the Bain circuit?

A modified Mapleson D Delivers fresh gas through the inner tube Exhaled gas travels through the outer tube Exhaled gas warms and humidifies fresh gas Can be used for spontaneous or controlled ventilation

Open circuit

A non contained system where the patient exchanges gas w/ the atmosphere No rebreathing and no reservoir

Return Pad

A point of exit for electrical current leaving the body - it is not a grounding pad (provides low impedance surface area)

Nerve fibers (myelination and function)

A-alpha: Heavy, motor A-beta: Heavy/Moderate, touch and pressure A-gamma: Moderate, proprioception (muscle tone) A-delta: Light, fast pain, temp, and temp B: Light, preganglionic and autonomic C: None, slow pain, temp, and touch

Drug effects on insulin secretion

Alpha-adrenergic stimulation inhibits insulin secretion Beta-blockers and anticholinergics inhibits insulin secretion Vagal stimulation, B2-adrenergic stimulation, & cholinergic drugs stimulate insulin secretion pSNS-> stimulate insulin secretion SNS-> inhibit insulin secretion

Interaction

Alteration in the therapeutic action of a drug by concurrent administration of other exogenous chemicals

altered pharmacokinetics/dynamics w/ liver dx

Altered volume of distribution: Intravascular volume unpredictable, esp with ascites tx ↓ serum albumin ↑ gamma globulins Porto-systemic shunted blood bypasses liver Drugs highly extracted by liver esp affected ↑ sensitivity to sedative medications (decreased metabolism, increased duration, increased GABA, NMDA inhibition)

IV Injection/Toxicity (LAST)

Always aspirate • Epidural - Test Dose • 3-5 mL 1.5% Lidocaine with 1:200k Epi • Rules out intrathecal or IV catheter placement • S/S: Restlessness, seizure, coma, cardiac collapse • Tx: LAST Protocols

Blood Conservation Techniques for CPB

Aminocaproic acid or Tranexamic acid Cell saver

What amplitude of an evoked potential indicates nerve ischemia

Amplitude decreases by > 50% or Latency increases by > 10%

T wave

Amplitude: < 10mm in precordial leads, <6mm in limb leads Usually points in same direction as QRS Points in opposite direction of QRS if repolarization is prolonged: Myocardial ischemia, BBB Peaked T waves: Hyperkalemia, Myocardial ischemia, LVH, intracranial hemorrhage

3 plasma proteins that bind drugs

albumin (acidic drugs) alpha1-acid glycoprotein (basic drugs) beta globulin (basic drugs)

Wolf-Parkinson-White Syndrome

An accessory conduction pathway that bypasses the AV node Forms a direct line of communication between the atria and the ventricles - there is no delay Definitive treatment is radiofrequency ablation

Prodrug

An inactive drug dosage form that is converted to an active metabolite by various biochemical reactions once it is inside the body. Fospropofol

sniffing position

An upright position in which the patient's head and chin are thrust slightly forward to keep the airway open. Head even with chest. Cervical flexion, Atlanto-occipital joint extension

RLN injury

Acute bilateral injury= bilateral paralysis of the vocal cords abductors & acute injury to both RLN = risk for stridor and respiratory distress Unilateral or chronic injury isn't as dangerous. paralysis of ipsilateral vocal cord abductors

Anesthetic considerations for alcoholsims

Acute intoxication (↓MAC - need less drug) Chronic alcoholism (↑MAC-need more drug) EtOH potentiates GABA-increased effect of benzo's EtOH inhibits NMDA receptors

Conditions that affect the pericardium

Acute pericarditis Constrictive pericarditis Cardiac tamponade

Delta receptors

Analgesia, Physical dependence respiratory depression urinary retention, pruritis Agonist: Enkephalins Antagonist: Naloxone, naltrexone, nalmefene

Risks of sugammadex

Anaphylaxis: 0.3% of population Bradycardia and cardiac arrest -> give anticholinergics binds oral contraceptives

Classic presentation of PDPH

fronto-occipital h/a -may be accompanied by n/v, photophobia, diplopia, and tinnitus -laying supine relieves h/a

Median Nerve wrist block

Anatomic landmarks: flexor carpi radial tendon & flexor palmaris longus tendon Inject 5mL between the flexor carpi radial tendon and the flexor palmaris longus tendon

Single chamber pacing

AAI, VVI A backup mode, it only fires when the native HR falls below a predetermined rate

What drugs reverse cardiac remodeling

ACE-i Aldosterone inhibitors (spironolactone)

Conditions that Succ can cause hyperkalemia

ALS Charcot-Marie Tooth Duchenne's MD Guillain Barre Hyperkalemic periodic paralysis MS Upregulation of AChR (burns)

Diseases that cause increased sensitivity to NDNMB's

ALS Duchenne's MD Guillain Barre Huntington's Chorea MS Myasthenia Gravis

Asynchronous pacing

AOO, VOO, DOO pacemaker delivers a constant rate No sensing and no inhibition can be a competitive underlying rhythm pacer spike delivered during repolarization can cause R on T phenomenon

Conditions associates with diastolic HF

AS ischemic heart disease Essential hypertension

When to d/c antiplatelet therapy

ASA: continue if you can (or 3 days b/f) Clopidigrel: 7 days b/f surgery Ticlodipine: 14 days b/f surgery If emergency, PLTs can be given to reverse Do not use heparin to bridge antiplatelet therapy

Recommendations for block placement: Glycoprotein IIb/IIIa antagonists

Abciximab: Hold 1-2 days Tirofiban, Eptifibatide: Hold 8h

Neuraxial recommendations w/ Glycoprotein IIb/IIIa antagonists

Abciximab: b/f block placement hold 1-2 days Tirofiban: b/f block placement hold 8h Eptifibatide: b/f block placement hold 8h

Signs of inadequate mask ventilation:

Absent or inadequate condensation in mask or EtCO2 waveform Absent or minimal chest rise Absent or inadequate breath sounds Gastric air entry Decreasing or inadequate oxygen saturation Cyanosis Hemodynamic changes associated with hypoxemia/hypercarbia

Absolute Contraindications to neuraxial anesthesia

Absolute • Patient Refusal/Inability to Remain Still • Localized Sepsis/Infection • Increased ICP

Methemoglobin

Absorbs 660nm and 940nm equally The 1:1 absorption ratio is read at 85% Falsely underestimates SpO2 if O2 sat is > 85% Falsely overestimates SpO2 if O2 sat is < 85%

Carboxyhemoglobin

Absorbs 660nm to the same degree as O2-Hgb CO-hgb and O2-Hgb look the same to the pulse ox Reads the sum of O2-Hgb + CO-Hgb (overestimates SpO2)

Factors that effect the speed of inhaled agent

Absorption into plastic (how much is absorbed by tubing etc Flow rate ventilation (RR, TV) Concentration Blood gas solubility (Speed) V/Q problems 2nd gas effect N2O diffusion into closed spaces Cardiac output Oil/gas solubility (potency) metabolism Diffusion hypoxia Peds Obesity Hypothermia

Mahaim Bundle

Accessory pathway: AV node to Ventricle

James fibers

Accessory pathway: Atrium to AV node

Atrio-hisian fiber

Accessory pathway: Atrium to Bundle of his

Kent's bundle

Accessory pathway: WPW (Wolff-Parkinson-White Syndrome) Atrium to Ventricle

hepatotoxic drugs

Acetaminophen (toxic metabolite NAPQI) Halothane (inorganic fluoride & TFA) alcohol (impairs fatty acid metabolism)

Treatment for Hyper or Hypokalemic periodic paralysis

Acetazolamide creates non-gap acidosis that counters hypokalemia facilitates renal potassium excretion that counters hyperkalemia

Molecular makeup of succinylcholine

Ach molecules joined together - this makeup is the basis for many of Succ side effects. This what Ach does throughout the body

Structural changes in pancreas d/t malnutrition

Acinar cell atrophy occurs Zymogen granules decrease ↓enzymatic activities of pancreatic juice ↓Digestion of fat and protein

Microglia

Act as phagocytes, eating damaged cells and bacteria, act as the brains immune system

acute pericarditis s/s

Acute CP w/ pleural component: increased pain w/ inspiration and positional changes Pericardial friction rub ST elevation w/ normal enzymes Fever

Endocrine complications from RA

Adrenal insufficiency and infections d/t steroids

Nine cartilages of larynx

Adult: C3-C6 3 Unpaired: Epiglottis, Thyroid, Cricoid 3 Paired: Arytenoid, Corniculate, Cuneiform

Where does the dural sac end?

Adult: S2 - correlates with the superior iliac spines infant: S3 subarachnoid space terminates at the dural sac

Reflex pathway for laryngospasm

Afferent limb: SLN internal branch Efferent limb: SLN external & RLN Tensing of cords: Cricothyroid muscle ADDuction of cords: lateral cricoarytenoid & thyroarytenoid

Laryngospasm risk factors

Age < 1 year Hypocapnea Light anesthesia Saliva or blood in the airway GERD Exposure to second hand smoke Recent URI

Formula to size pediatric ETT

Age/4 + 4 = ETT size (subtract 0.5 for cuffed tube) Age=most reliable indicator of appropriate tube size for children ETTx3 = ~depth

Factors that increase PDPH

Age: younger Sex: female larger needle size needle bevel perpendicular to spinal nerves pregnancy dural punctures (multiple) Do not increase: timing of ambulation, cont spinal infusion

Causes of over-dampening

Air bubble Clot low flush bag pressure

What happens if air enters the venous line of the CPB

Air lock

Decreases as the airway bifurcates

Airflow velocity Amount of cartilage Goblet cells (mucus) Ciliated cells

Complications of the prone position

Airway edema - leak test ETT mainstem or kink Cerebral hypoperfusion - neck rotation -> venous compression Ischemic optic neuropathy Corneal abrasion brachial plexus injury Ulnar n injury DVT (hip flexion -> femoral vein occlusion) Lateral femoral cutaneous n. injury (iliac crest pressure) peroneal n. injury (Lateral fibula pressure) ↑abdominal pressure

What does an increased alpha angle A indicate?

Airway obstruction (increased resistance) - COPD, bronchospasm, kinked tube

upper respiratory tract muscles

Airway obstruction is prevented by these 3 dilator muscles: Tensor palatine: Opens the nasopharynx (soft palate) Genioglossus: Opens the oropharynx (tongue) Hyoid Muscle: Opens the hypopharynx (epiglottis)

Scleroderma anesthetic considerations

Airway: limited mouth opening Respiratory: Pulmonary fibrosis & pulmonary HTN Heart: Dysrhythmias and CHF Blood vessels: decreased compliance -> HTN Kidneys: renal failure & renal artery stenosis -> HTN Peripheral & cranial nerves: nerve entrapment -> neuropathy eyes: dryness -> corneal abrasion

Liver dx preop labs

Albumin, CBC, coags, electrolytes, glucose, ALT & AST, AlkPhos, Blood type and screen, serum ammonia level, toxicology screen if suspected substance abuse

Acute pancreatitis causes

Alcohol abuse Trauma to or near pancreas Ulcerative penetration from adjacent structures (i.e. duodenum) Infection Biliary tract disease Metabolic disorders (HLD, hypercalcemia) Drugs (corticosteroids, furosemide, estrogens, thiazide diuretics) Surgery (post operative pancreatitis) Mobilization of abdominal viscera Cardiopulmonary bypass

Which Anilidopiperidine has the fastest onset

Alfentanil d/t it low degree of ionization (pka: 6.5) - crosses the BBB faster Has a low Vd and high degree of protein binding

Triangular intubation axes

Align oral axis, pharyngeal axis, and laryngeal axis

Where is the choroid plexus located?

All cerebral ventricles

Opioid allergy

All phenanthrene's and Meperidine stimulate histamine release. Allergies are related to chemical class. If you're allergic to one drug in the class, you're allergic to all of them, but you can have one from a different class.

Modified RSI

Allows for gentle ventilation with cricoid pressure maintained

Semi-closed circuit

Allows rebreathing FGF is less than minute ventilation Unidirectional valves increase airway resistance Some rebreathing w/ a reservoir

What is the Pethick test?

Allows you to test the integrity of the inner tube of Bain circuit 1. Occlude the elbow at the pt end of the circuit 2. Close the APL valve 3. Push the O2 flush valve to fill the circuit 4. Remove the occlusion at the elbow while flushing the circuit.

Radial Nerve wrist block

Anatomic landmarks: radial styloid Subq injection = 10mL proximal to the radial styloid (field block)

superficial peroneal nerve

Anterior to the lateral malleolus Sensation to the dorsum of the foot

Additional clinical use of Physostigmine

Anti-shivering - same efficacy of meperidine and clonidine

Eaton-Lambert Syndrome

Antibodies formed against presynaptic calcium channels (decreases release of ACh) STRONGLY associated with Small Cell Carcinoma and Smokers -Sensitive to non-depolarizing and depolarizing NMB's -Resistant to reversal w/ anticholinesterase agents

What causes SLE symptoms

Antibody induced vasculitis and tissue destruction

Scapolamine patch

Anticholinergic. Dose: 2.5cm2 patch contains 1.5mg Onset: 2-4h (may be longer). Duration: at least 24h-PDNV. Blocks cholinergic impulses at the vestibular nuclei to higher venters in the CNS (CTZ)

Nasal airway contraindication

Anticoagulated Sepsis Children with prominent adenoids Caution in patients with basilar skull fractures

Carotid artery angioplasty stenting (CAS)

Anticoagulation w/ heparin: ACT 250-300 Balloon inflation can activate baroreceptors -> bradycardia and hypotension thromboembolic stroke most common complication distal filter is placed embolic stroke is treated w/ recombinant TPA

Patient factors that increase risk of pulmonary artery rupture

Anticogulation Hypothermia Advanced age

Promethazine (Phenergan)

Antihistamine Dose: 12.5-25mg IV Sedation prominent

hydroxazine (Atarax)

Antihistamine Dose: 12.5-25mg IV Sedation prominent

Diphenhydramine (Benadryl)

Antihistamine Dose: 25mg IV Sedation prominent

Hematologic complications of SLE

Antiphospholipid antibodies Hypercoagulability Anemia Thrombocytopenia Leukopenia

Use of bupivicaine, levobupivicaine, ropivicaine in pediatrics

Any concentration is ok as long as dose does not exceed 2.5mg/kg

Unacceptable response to twitch monitor (axillary)

Anything else

Anterior cerebral circulation

Aorta -> Carotid artery -> Internal carotid artery -> Circle of Willis -> Cerebral hemispheres enter the skul through the foramen lacerum

Posterior cerebral circulation

Aorta -> Subclavian artery -> vertebral artery -> Basilar artery -> Posterior fossa structures and cervical spinal cord

Anterior spinal artery

Aorta -> subclavian a -> vertebral a -> anterior spinal a Aorta -> segmental a -> posterior radicular a -> anterior spinal a Perfuses the anterior 2/3 of the spinal cord

Posterior spinal arteries

Aorta -> subclavian a -> vertebral a -> posterior spinal a Aorta -> segmental a -> posterior radicular a -> posterior spinal a Perfuses the posterior 1/3 of the spinal cord

Crawford classification of thoracoabdominal aneurysms

Aortic aneurysms Type 1: all or most of descending thoracic, top part only of abdominal Type 2: all or most of descending thoracic, most of abdominal Type 3: lower only of descending thoracic, most of abdominal Type 4: none of descending thoracic, most of abdominal

When does PAOP underestimate LVEDV

Aortic insufficiency

Common cardiac conditions caused by Marfans

Aortic insufficiency & AAA (dilated aortic root), mitral valve prolapse, mitral regurg, aortic dissection, spontaneous pneumothorax is common complication

Factors that cause erroneous esophageal doppler measurements

Aortic stenosis Aortic insufficiency Disease of thoracic aorta Aortic cross clamping After CPB Pregnancy

How are Evoked potentials produced

Applying current to a neural pathway

Cerebellum

Archeocerebellum: Equilibrium Paleocerebellum: regulates muscle tone Neurocerebellum: coordinates voluntary muscle movement

watershed areas

Areas of the spinal cord that have a single blood supply - particularly susceptible to ischemia

Supraclavicular indications and Landmarks

Arm, elbow, forearm, wrist, and hand (not shoulder) Landmarks: Subclavian artery (best), clavicle

Complications while obtaining a central line

Arterial puncture Pneumothorax Air embolism Neuropathy Catheter knot

Perfusion of liver lobule (blood flow)

Arterioles: hepatic artery (25% bld flow, 50% O2) & portal vein (75% bld flow, 50% O2) Capillaries: sinusoids Venules: central vein 30% CO

Guillain-Barre S/S

Ascending muscle weakness up to face (distal to proximal) Intercostal muscle weakness (may need mechanical ventilation) Facial and pharyngeal weakness -> aspiration risk Sensory deficits: paresthesias, numbness, &/or pain ANS dysfxn: tachy or brady-cardia, HTN or HoTN, diaphoresis or anhidrosis, orthostatic HoTN

Autonomic Nervous system dysfunction in DM

Aspiration Nausea and vomiting Abdominal distension Preoperative aspiration prophylaxis: H2-receptor blockers, gastroprokinetic agents, pre-induction antacids Intubation during GA FBG above 350 may warrant cancellation Autonomic neuropathy: Impaired respiratory response to hypoxia

Risks to consider w/ Myotonic dystrophy

Aspiration Respiratory muscle weakness cardiomyopathy & dysrhythmias Sensitive to anesthetic agents (No increased risk for MH)

benzylisoquinolinium compounds metabolism/elimination

Atracurium (non-specific plasma esterases > hofmann's) Cisatracurium (Hofmann's) Mivacurium (pseudocholinesterases)

NMB that can be implicated in seizures

Atracurium d/t laudanosine production - mostly caused by long term infusions Laudanosine is also a metabolite of Cis, but it is produced in much smaller quantities.

Third Degree Heart Block (Complete Heart Block)

Atria and ventricles have their own rate, completely divorced from each other Tx: Pacemaker or Isoproterenol Can lead to CHF d/t decreased HR and CO Stokes-Adams attack = decreased CO -> decreased cerebral perfusion -> syncope

large A waves

Atria contracting against high resistance tricuspid stenosis Diastolic dysfxn Myocardial ischemia Chronic lung disease that causes RV hypertrophy AV dissociation Junctional rhythm V-pacing (asynchronous) PVC's

Molecular structures of muscarinic antagonists

Atropine & Scopolamine: Quaternary Amines (crosses BBB) Glyco: Tertiary Amine (ionized = does not cross BBB)

Treatment for ↑ biliary pressure

Atropine, nitro, glucagon, narcan

Muscarinic antagonists effects decreasing gastric H+ secretion

Atropine: + Scopolamine: + Glyco: +

Muscarinic antagonists antihistalogue effects

Atropine: + Scopolamine: +++ Glyco: ++

Muscarinic antagonists effects on preventing motion sickness

Atropine: + Scopolamine: +++ Glyco: 0

Muscarinic antagonists mydriasis/cycloplegia effects

Atropine: + Scopolamine: +++ Glyco: 0

Muscarinic antagonists sedation effects

Atropine: + Scopolamine: +++ Glyco: 0

Muscarinic antagonists effects on smooth muscle relaxation

Atropine: ++ Scopolamine: + Glyco: ++

Muscarinic antagonists effects on heart rate

Atropine: +++ Scopolamine: + Glyco: ++ does not affect heart transplant pt's but they still need a muscarinic antagonist because they still experience all the other cholinergic effects of reversal agents

Dibucaine test

Atypical PChE can't hydrolize Succ - makes succ last longer Normal test: 80, Dibucaine has inhibited 80% of PChE activity in a sample (normal level of PChE) Abnormal test: 20, Dibucaine did not inhibit an adequate amount of PChE activity meaning that the Atypical variant is present. There is sufficient enzyme but it is not functional.

Order of blockade for spinal

Autonomic block is 2-6 dermatomes higher than sensory. Sensory is 2 dermatomes higher than motor.

Prevention of Laryngospasm

Avoid airway manipulation during light anesthesia CPAP 5-10 during inhalation induction or immediately after extubation Clear pharyngeal secretions or blood before extubation Deep or fully awake extubation Laryngeal lidocaine IV lidocaine before extubation Hypercapnea/Hypoventilation PaO2<50

Classic presentation of PDPH

fronto-occipital h/a that worsens w/ sitting up N/V photophobia diplopia tinnitis

Loop diuretics MOA

furosemide, bumetanide, torsemide Inhibits Na-K-2Cl transporter in thick ascending loop of henle

Factors that do not significantly affect spread in spinal anesthesia

Barbotage Increased intra-abdominal pressure Speed of injection Orientation of bevel Addition of vasoconstrictor Weight Gender

Determinants of block height

Baricity and patient position Block level should be 2-3 segments above the expected level of surgery

Baricity

Baricity is the specific gravity (density) of a LA relative to the CSF at 37C.

Beck's triad

hypotension, JVD, muffled heart sounds

The heart depolarizes from the ________ to the ________

Base to apex endocardium to epicardium Repolarization happens in the opposite direction

Hofmann's Elimination

Based on Body temp and pH -faster with alkalosis and hyperthermia -slower with acidosis and hypothermia

Presentation of cardiac tamponade

Beck's triad Pulsus paradoxus Kussmaul's sign reduced EKG voltage - Narrow pulse pressure Tachypnea Tachycardia Compression of the heart, lungs, trachea, and esophagus

S/S of neurogenic shock

hypotension, bradycardia, hypothermia w/ pink, warm extremities sympathectomy below the injury can last 1-3 weeks

Anterior spinal artery syndrome

Becks syndrome Caused by aortic cross-clamp above the artery Adamkiewicz -Flaccid paralysis of the lower extremities -Bowel and bladder dysfunction -Loss of temp and pain sensation -Preserved touch and proprioception

Treatment for PDHP

Bed rest Hydration NSAIDs caffeine Epidural blood patch Sphenopalantine ganglion block

What is pulse oximetry based on

Beer-Lambert law = relates the intensity of light transmitted through a solution and the concentration of the solute w/in the solution solution=blood solute=Hgb

S/S of Hypovolemic shock

hypotension, tachycardia, and cool, clammy extremities

Trachea

Begins at C6, ends at T4-5 2.5cm wide, 10-13cm long Sensory innervation: Vagus Blood supply: inferior thyroid a., superior thyroid a., Bronchial a., internal thoracic a.

Lower motor neuron

Begins the ventral horn and ends at the NMJ Link the spinal cord to muscles

Which subunits need to be occupied to open the nicotinic receptor

alpha and alpha the channel opens when both are occupied and Na+ & Ca++ flow in, K+ flows out.

pain transduction

Begins when tissue is damaged causing the release of chemical mediators which activate peripheral nerves (nociceptors). Those chemical mediators are turned into an action potential that travels along the nerve. Nearby immune cells may also be stimulated to release proinflammatory mediators.

Which type of calcium channel do CCB's bind to?

alpha subunit of L-type

What muscular diseases are NOT associated w/ MH

Beker muscular dystrophy Neuroleptic malignant syndrome myotonia congenita myotonic dystrophy

Use of CCB's for control of vascular tone

Best coronary antispasmodic: Nicardipine Best cerebral vasospasm: Nimodipine Best in treatment of HTN from ↑ SVR: Nifedipine, amlodipine, nicardipine

Inferior valeculla

Between the inferior ridge of the epiglottis and true vocal cords

What muscles does the sciatic nerve innervate?

Biceps femoris Semitendinosus Semimembranosus

Verify ETT placement

Bilateral chest rise Bilateral breath sounds Auscultate stomach ETCO2

Bile functions

Bile is primary secretion of the liver -absorption of fat and fat soluble vitamins (DAKE) -Metabolic excretion -Alkalization of the duodenum

adenocarcinoma: pancreatic cx

Biliary obstruction likely (jaundice) Insulinoma: Cancer of beta cells, Insulin-secreting tumor of the islets of Langerhans, Profound hypoglycemia

Neuraxial recommendations w/ warfarin

B/f block hold 5d catheter can be removed when INR < 1.5

Risk Factors for difficult mask ventilation

BONES Beard Obese (BMI>26) No teeth (edentulousness) Elderly (>55y) Snoring

Classic triad of AAA rupture

Back pain Hypotension pulsatile abdominal mass

BURP maneuver

Backward, Upward, Rightward Pressure on thyroid cartilage -Displaces larynx, may improve visualization of the glottis

Complications during catheter residence

Bacterial colonization Myocardial or valvular injury Sepsis Thrombus Thrombophlebitis Misinterpretation of data

Factors that do not affect spread for spinal

Barbotage Increased abdominal pressure (labor, coughing) Speed of inj orientation of bevel Addition of vasoconstrictor Weight Gender

steal phenomenon

Blood vessels that supply ischemic or atherosclerotic regions are maximally dilated. Therefore anything that causes cerebral vasodilation (↑PaCO2/vasodilators) can decrease the blood supply to these ischemic tissues as some of it is diverted to newly dilated vessels

Causes of increased volume for blood, brain, CSF

Blood: ↑CBF, bleeding Brain: Cerebral swelling, tumor CSF: ↑production by choroid plexus, reduced CSF removal by arachnoid villi, obstruction to reabsorption (infx, bleed, tumor), passage of fluid across the BBB

Sugammadex elimination

Both sugammadex and sugammadex-roc complex are eliminated by the kidneys

Cauda Equina s/s

Bowel and bladder dysfxn, sensory dysfxn, weakness +/- paralysis

Succ A/E

Bradycardia: M2 receptor on SA node) peds and/or 2nd dose Tachycardia and HTN (more common in adults than bradycardia) Hyperkalemia: usually transient unless there extrajunctional receptors are present Increased intraocular pressure (caution w/ open globe injuries) Increased ICP Increased intragastric pressure & lower esophageal sphincter tone Malignant Hyperthermia: Masseter spasm can be first sign - however can also be normal fasciculation so must correlate w/ other clinical signs

Opioid target

Brain, Spinal cord, GI GI has the largest amount of opioid receptors

Where are opioid receptors located?

Brain: periaqueductal gray, locus coeruleus, and rostroventral medulla Spinal Cord: Primary afferent neurons in the dorsal horn and the interneurons Periphery: sensory neurons and immune cells

recurrent laryngeal nerve (RLN)

Branch of the vagus nerve Sensory: Below the level of the vocal cords -the trachea Motor: All intrinsic muscle except the cricothyroid Location: Runs under the aortic arch, ascends the trachea to the larynx. L RLN injury (PDA ligation, left atrial enlargment).

superior laryngeal nerve (SLN)

Branch of the vagus nerve, branches at the level of the hyoid. Internal branch Sensory: posterior side of epiglottis. Laryngeal mucosa to the level of VC's. Motor: 0 External branch Sensory: 0 Motor: Cricothyroid muscle Unilateral injury causes no harm, bilateral injury causes hoarseness

Axillary block level

Branches

Renovascular disease clinical findings

Bruit (epigastric or abdominal), Severe HTN in young pts Diagnostics: CT angio, MRI, Aortography Duplex US

Cauda equina

Bundle of spinal nerves extending from conus meddularis to the dural sac

What is the cauda equina?

Bundle of spinal nerves extending from conus medullaris to dural sac.

Hypobaric solutions (Lighter)

Bupivicaine 0.3% in water Lidocaine 0.5% in water Tetracaine 0.2% in water

Isobaric solution (Same)

Bupivicaine 0.5% in saline Bupivicaine 0.75% in saline Lidocaine 2% in saline Tetracaine 0.5% in saline

Hyperbaric solutions (Heavier)

Bupivicaine 0.75% in 8.25% dextrose Lidocaine 5% in 7.5% dextrose Tetracaine 0.5% in 5% dextrose Procaine 10% in water

How does neuraxial anesthesia affect the neuroendocrine response to stress?

Inhibits afferent traffic originating from the surgical site -> stress stimulus does not make it to the brain

Wavelength of oxygenated hgb

Near infrared light (940nm)

What decreases CMRO2

hypothermia halogenated agents propofol etomidate barbituates

MAC awake

alveolar concentration when the pt opens their eyes during induction: 0.5-0.6 during recovery: 0.15

F(A)

alveolar gas concentration = determined by: -uptake -ventilation -concentration and 2nd gas effect

Other confounding factoring that affect evoked potentials

hypoxia hypercarbia hypothermia Ketamine enhances the signal

Essential triad of anesthetic action

amnesia Loss of consciousness Immobility (effects are dose dependent - loss of consciousness happens at a lighter depth than immobility)

Concentration

amount of drug in a given blood volume

Complication of opioid induced muscle rigidity

CV: ↑CVP, ↑PAP, ↑PVR Resp: Hypoxia, Hyercapnia, ↑O2 consumption, ↓SVO2, ↓thoracic compliance, ↓FRC, ↓Minute ventilation ↑ICP, ↑Gastric pressure (w/ masking)

RV diastolic pressure is equal to?

CVP

Channel dysfxn associated w/ Hypokalemic periodic paralysis

Ca+ channelopathy

Class IV antiarrhythmic drugs

Ca++ channel blockers ↓conduction through the AV node ex. verapamil, diltiazem

Mandibular protrusion test

Class 1: can bite vermillion with lower incisors Class 2: Lower incisor (LI) line with Upper Incisor (LI) Class 3: LI are behind UI (cannot move further)

Anti-arrythmic drug classes

Class I: inhibit fast sodium channels Class II: BB's - ↓rate of depolarization Class III: Potassium channel blockers Class IV: CCB - inhibit slow calcium channels

how is the epidural space connected to the paravertebral space

intravertebral foramina

LMA maximum airway seal pressures (leak pressure)

Classic LMA: 20cmH2O ProSeal, Supreme LMA (disposable version of proseal): ~30mmHg (slides say >40) igel LMA: ~30mmHg Limit TV to 8mL/kg

Differential block

Clinical phenomenon that nerve fibers with different functions have different sensitivities to local anesthetic blockade

plasma protein binding in relation to Vd

inversely related

Cervical dermatomes

C2: Back of head C3: entire neck C4: clavicular, scapular, and shoulder region C5: deltoid area C6: half of forearm, thumb C7: middle finger C8: , side of hand, ring finger, little finger

Level of phrenic nerve

C3-C5 3,4,5 stay alive

Post pump vasoplegia

Clinical picture is hyperdynamic with high cardiac output and very low SVR. It is a kind of distributive shock (heart is trying to compensate for lack of vascular tone. Can be treated with catecholamine vasopressors (levo, epi, phenylephrine) If the heart is resistant to catecholamines, treat with Vaso

Roots

C5-T1

Most common site of spinal cord injury

C7

formula for cerebral blood flow

CBF = Cerebral Perfusion Pressure / Cerebral Vascular Resistance

Critical thresholds for CBF

CBF ~20mL/100g/tissue/min = ischemia CBF ~15mL/100g/tissue/min = complete cortical suppression CBF <15mL/100g/tissue/min = membrane failure & cell death

Procedures that can benefit from EEG monitoring

CEA Cerebral aneurysm AV malformations CPB Deliberate hypotension Barbiturate coma Epilepsy diagnosis and treatment Coma and death

Which nerves carry pSNS output

CN 3, 7, 9, 10 Oculomotor Facial Glossopharyngeal Vagus Vagus is responsible for 75% of pSNS output

Which cranial nerve is implicated in Bell's Palsy

CN VII: facial ipsilateral facial paralysis

Which cranial nerve is part of the CNS rather than the PNS

CNII: optic meaning it is the only cranial nerve surrounded by dura

What nerve innervates the face (sensory)

CNV: trigeminal

Where does parasympathetic innervation of the gut come from?

CNX - vagus sympathetic innervation comes from sympathetic chain T5-L2

Causes of right axis deviation (RAD)?

COPD Acute bronchospasm Cor Pulmonale Pulmonary HTN Pulmonary embolism

VIA in patients who rely on hypoxic drive

COPD, OSA Des is best agent - affects hypoxic drive the least

Cerebral Perfusion Pressure (CPP)

CPP = MAP - ICP (or CVP whichever is higher) (70-90mmHg)

Anesthetic mgmt of TBI

CPP > 70mmHg No steroids Avoid prolonged hyperventilation (can worsen cerebral ischemia - only use acutely) Hypertonic fluids Avoid hypotonic solutions & glucose containing solutions (use only for hypoglycemia) Avoid albumin (poorer outcomes) No N2O

Autoregulation range

CPP: 50-150mmHg or MAP: 60-160mmHg CPP = MAP - ICP or CVP (whichever is higher)

Major chemical differences between CSF and plasma

CSF has lower potassium, lower PaCO2, lower pH, lower glucose and extremely lower protein content (almost none)

CSF volume and specific gravity

CSF volume: ~150mL CSF specific gravity: 1.002 - 1.009 produced by ependymal cells at rate of 30mL/h

Contents of the subarachnoid space

CSF, nerve roots, rootlets, spinal cord (spinal cord is covered by the pia mater)

What medication class should never be given with MH

Calcium channel blocker - can precipitate Hyperkalemic cardiac arrest when given with Dantrolene

cyctic fibrosis

Can cause acute pancreatitis that leads to chronic pancreatitis: Mutation in CRTF-> disrupts ion transport-> pancreatic secretions become thick and sticky-> obstructions

Inhaled anesthetic effect on seizures

Can cause seizures but usually EEG activity is suppressed in a dose dependent fashion

Affect of co-administration of Meperidine and MAOI's

Can cause serotonin syndrome b/c Meperidine is a weak serotonin reuptake inhibitor

Biphasic Expiratory Plateau

Can occur after a single-lung transplant Alveolar gas from the lung and the diseased lung have different time constants First peak is alveolar gas from the transplanted lung

Afib w/ WPW

Can precipitate CHF, VF and death Procainamide is treatment of choice. If hemodynamically unstable then cardioversion

High concentration Sevo (2.0 MAC)

Can produce seizures-more common w/ pediatric inhalation induction

Functions of the liver

Carbohydrate metabolism: Gluconeogenesis, Glycogenolysis, Glycogenesis Protein synthesis: Albumin (osmolarity), Thrombopoietin (platelet production) Amino Acid synthesis Protein metabolism Bile production (1L/day) Lipid metabolism, Lipogenesis, Cholesterol synthesis Coagulation factor synthesis: Factors I, II, V, VII, IX, X, XI Insulin clearance Drug metabolism/ transformation Bilirubin metabolism

Biochemical effect of VIA

Cardiac and Vascular smooth muscle: ↓ Ca++ influx through the sarcolemma and ↓Ca++ release from SR -modulate NO release, inhibit Ach-induced vasodilation, and impair Na+/Ca++ pump ↓ intracellular Ca++ concentration Effect: Myocardial depression and vasodilation

Consequences of electrical injury

Cardiac arrhythmias Nerve injury -> muscle contractions and diaphragmatic paralysis Thermal injury (organ injury may be more comprehensive to damage on the skin)

Indications for IABP

Cardiogenic shock MI intractable angina Difficult separation from CPB

Intermediate-risk procedures for cardiac morbidity and mortality (1-5% risk) - per AHA guidelines

Carotid endarterectomy Head and neck surgery Intrathoracic or intraperitoneal Orthopedic surgery Prostate surgery

Too long of an oral airway = ____

Causes airway obstruction to laryngeal inlet by compressing the epiglottis = trauma/laryngospasm

SLN injury

Causes hoarseness b/c cricothyroid muscle cannot be tensed.

Downside of partial agonists

Ceiling effect for analgesia Reduce the efficacy of previously administered opioids Can cause opioid withdrawal is opioid dependent patients

VIA pharmacologic effect and target region for unconsciousness

Cerebral cortex: higher order cerebral fxns Thalamus: Relay station for input Reticular Activating System: consciousness & arousal

Diseases of the upper motor neuron

Cerebral palsy ALS

Cervical & thoracic spinous process directionality vs lumbar spinous process directionality

Cervical & thoracic: angled in a caudal direction Lumbar: posterior direction

Spine anatomy

Cervical (7 vertebrae) Thoracic (12 vertebrae) Lumbar (5 vertebrae) Sacral (5 vertebrae)

Needle trajectory

Cervical and thoracic vertebrae overlap each other and are angled caudally. Angle needle cephalad. Lumbar spaces are larger and more straight.

Compliance

Change in Volume/Change in Pressure Change in volume for a given change in pressure

CSF

Characteristics • Clear • Occupies the Subarachnoid Space • Acts as a cushion and shock absorber Produced in the Choroid Plexus Body produces ~500mL/day Specific Gravity - 1.004-1.009

ionized

Charged, water soluble, can't pass thru membranes

What areas of the brain are not protected by the BBB

Chemo trigger zone, posterior pituitary gland, pineal gland, choroid plexus, part of hypothalmus

Order of duration (fast to slow) for spinal

Chloroprocaine 3%: 40-90min Lidocaine 5%: 60-150min Mepivacaine 1.5%: 120-180min Ropivacaine 0.5-1%: 80-210min Levobupivacaine 0.5%: 140-230min Bupivacaine 0.5-0.7%: 130-230min

Cause of left axis deviation (LAD)?

Chronic HTN LBBB Aortic Stenosis Aortic Insufficiency Mitral regurgitation Pregnancy

Uses for Meperidine

Chronic treatment of opioid abuse Chronic pain syndrome Cancer pain

Examples of Semi-closed circuit

Circle system (FGF < Minute Ventilation)

Example of closed circuite

Circle system with very low FGF and closed APL vavle

3 things capnography can be used to assess

Circulation Ventilation CO2 production: Metabolism

ED95 of NMBs

Cisatracurium: 0.04mg/kg Vecuronium: 0.043mg/kg Mivacurium: 0.067mg/kg Pancuronium: 0.067mg/kg Atracurium: 0.21mg/kg Succ: 0.3mg/kg Rocuronium: 0.305mg/kg

Modified New York Association Functional Classification of Heart Failure

Class 1: Asymptomatic Class 2: Symptomatic w/ moderate activity Class 3: Symptomatic w/ mild activity Class 4: Symptomatic at rest

Recommendations for block placement: Thienopyridine inhibitors

Clopidogrel: Hold 7 days Ticlopidine: Hold 14 days

Neuraxial recommendations w/ Thienopyrodine derivatives

Clopidogrel: b/f block placement hold 7 days Ticlodipine: b/f block placement hold 14 days

Aryepiglottic muscle

Closes the laryngeal vestibuletongue

Codeine

Codeine is a prodrug which is metabolized to morphine. People who are fast metabolizers can end up w/ a toxic level of morphine (respiratory depression). This is why we don't give in to children. CYP2D6 pKa: 8.2 (14% nonionized)

Sacral hiatus

Coincides w/ S5 -covered by the sacrococcygeal ligament -provides entry point to the epidural space

Sacral Hiatus

Coincides with S5 inferior opening of the sacral canal - entry to epidural space

Methods to cool the patient

Cold IVF Cold fluid lavage of stomach and bladder Ice packs

Lower thoracic T6-T8 inj

Colectomy anterior resection Upper abdominal surgery (spread is more cephalad than caudel

competitive v non-competitive antagonism

Competitive -reversible -shifts the agonist to the right (makes it less potent) -increasing concentration of agonist can overcome competitive antagonism Non-Competitive -irreversibly binds (covalent bond) -effect is not overcome by adding more agonist -ex. ASA (life of platelet)

Closed circuit

Complete rebreathing of exhaled gad Uses very low FGF Gas does not exit the scavenger APL valve is closed Change in gas concentration is very slow d/t low FGF Complete rebreathing w/ a reservoir

Three compartment model

Comprised of central compartment rapidly equilibrating peripheral compartment slowly equilibrating peripheral compartment

Neuraxial opioid effect on the sympathetic system

opioids do not affect sympathetic system. They also do not cause skeletal muscle weakness or changes in proprioception

Hypoglycemia s/s (awake)

Confusion Dizziness Headache Weakness Seizure Aberrant behavior Loss of consciousness

Phase 2 drug metabolism

Conjugation reactions Phase I product (substrate) conjugates with a second molecule to make it water soluble Leads to formation of covalent linkage b/w functional group and glucuronic acid, sulfate, glutathione, amino acid, or acetate (e.g.,morphine,acetaminophen)

Phase 2 metabolism

Conjugation reactions in which a polar molecule is linked to a suitable functional group on a drug or one of its Phase 1 metabolites

What are internodal tracts

Connect the conduction system from the right to left atrium

Plica mediana dorsalis

Connective tissue between ligamentum flavum and dura mater (in epidural space) - theoretical - considered to be a cause for difficult epidural cannulation and unilateral blocks

Opioid gastrointestinal effects

Contraction of sphincter of Oddi -> ↑biliary pressure N/V Prolonged gastric emptying slowed peristalsis -> constipation

Stroke Diagnosis

Contrast CT - if bleeding is ruled out by CT, ischemic stroke is assumed & TPA can be given. ASA is an alternative if TPA cannot be given

Factors that significantly affect the spread in spinal anesthesiaP

Controllable Factors: -baricity of local anesthesia -patient position -Dose -site of injection Uncontrollable Factors: -Volume of CSF -Density of CSF

Magnet effect with a pacemaker

Converts pacemaker to asynchronous mode

Infraclavicular block level

Cords (posterior, medial, lateral)

Factors that cause erroneous pulse contour measurements

spontaneous breathing Small Vt PEEP Open chest RV dysfxn Dysrhythmias

Surgeries based on dermatomes

thoracic: T4-T8 Upper abdominal: T6-T8 Middle abdominal: T7-T10 Lower abdominal: T8-T11 Lower extremity: L1-L4

What part of the spine is generally not affected by RA?

thoracolumbar spine

Anesthetic considerations for MS

Cranial nerve involvement causes bulbar muscle dysfxn -> aspiration risk Hyperthermia & stress can cause exacerbations Succ can cause life-threatening hyperkalemia

Degrees of epidural needles (3)

Crawford: 0 degrees Hustead: 15 degrees Tuohy: 30 degrees

What proteins exit the cells due to the lack of dystrophin

Creatinine phosphokinase and myoglobin

Airway complications of SLE

Cricoarytenoiditis - hoarseness, stridor, airway obstruction Recurrent laryngeal nerve palsy

Only complete cartilaginous ring in the airway

Cricoid

____ separates the upper and lower airway

Cricoid cartilage

intrinsic laryngeal muscles

Cricothyroid Vocalis Thyroarytenoid Posterior Cricoarytenoid Lateral Cricoarytenoid Interior arytenoid

Second order neuron (Anterolateral)

Crosses to the contralateral side of the spinal cord Ascends toward the brain via 2 pathways: anterior spinothalamic & lateral spinothalamic Cell body in the dorsal horn Synapse in the Reticular Activating System or the thalamus

Conditions that cause falsely decrease BP

Cuff too large = Cuff pressure required to occlude the artery is lower with a cuff that is too large Cuff deflated too rapidly BP measured on extremity above the heart

Conditions that cause falsely elevate BP

Cuff too small = Cuff pressure required to occlude the artery is higher with a cuff that is too small Cuff is too loose BP measured on extremity below the heart

Functions of electrocautery

Cut, coagulate, dissect, or destroy tissue higher frequencies has a lower penetration and do not affect excitable cells - ie vfib is not a risk

Spinal Needles

Cutting vs. Non Cutting • All needles have stylet (avoid coring) • Quinke - Standard Cutting Needle • 22-25 guage

Intermediate signs of MH

Cyanosis Patient warm to the touch Irregular heart rhythm

PDPH factors

• Needle Gauge • Cutting vs Pencil Tip • Bevel Direction • Air used for loss of resistance over saline

What is perfused by the Anterior blood supply?

Corticospinal tract (flaccid paralysis of LE's) Autonomic motor fibers (bowel and bladder) Spinothalamic tract (pain and temp) -dorsal column is perfused by posterior blood supply (retain touch and proprioception)

SLE treatment

Corticosteriods NSAIDs Immunosppressents Antimalarials

Laser ETT

Covered with nonflammable material, some made of metal

hepatocyte metabolic functions

Glycogenesis Glycogenolysis Gluconeogenesis Proteins: amino acid deamination converts ammonia to urea Lipids: beta oxidation, trigylceride storage Synthesis of cholesterol, phospholipids, lipoproteins Conjugates bilirubin w/ glucuronic acid, excreted in bile Drug metabolism

cricoid pressure

Pressure on the cricoid cartilage; applied to occlude the esophagus to inhibit gastric distention and regurgitation of vomitus during RSI Pressure b/f LOC=20 newtons or 2kg Pressure after LOC=40 newtons or 4kg

Nalmfene

Pretty much like naloxone with a longer half life of 10h - can be used to maintain recovery in abusers

How do VIA create reactive oxygen species

through metabolism (biotransformation) - so the agents that undergo the most biotransformation impair the hypoxic drive the most: Halothane > Sevo > Iso > Des

Things that do not effect MAC

thyroid disease Gender PacCO2 15-95mmHg HTN

3 procedures that warrant prophylactic abx

Dental procedures (breaking oral mucosa) Bronchial biopsy (respiratory mucosa) Biopsy of infective lesions of skin or muscle

Causes of right shift on the PaCO2 response curve

Depresses Ventilation -General anesthetics -Opioids -Metabolic alkalosis -Denervation of peripheral chemoreceptors (like in CEA)

Dual chamber (AV sequential) Demand pacing

DDD most flexible and most common mode makes sure atrium contracts followed by the ventricle Improves AV synchony

DMD association w/ MH

DMD is associated w/ MH-like syndrome Its really rhabdomyolysis - any cardiac arrest on induction of a DMD pt should be considered to have severe hyperkalemia. Dantrolene does not treat this d/o. They have a normal ryanodine receptor. Succ and volatile anesthetics can trigger this syndrome.

Cholinergic side effects

DUMBBELLS Diarrhea Urination Miosis Bradycardia Bronchospasm Emesis Lacrimation Laxation Salivation

Partial pressure

Dalton's law the contribution each gas in a mixture makes to the total pressure

Aortic dissection classification

DeBakey: Type A: Involves ascending aorta, Type B does not Sanford: Type 1: Tear in ascending aorta & dissection along the whole aorta Type 2: Tear in ascending aorta & dissection only in the ascending aorta Type 3a: Tear in proximal descending aorta, dissection limited to thoracic aorta Type 3b: Tear in proximal descending aorta, dissection along thoracic and descending aorta

Which DeBakey and Sanford dissections are medical emergencies

Debakey Type 1 & 2 /Sanford Type A -these cause aortic insufficiency

Liver dx effects on NMB's

Decrease pseudocholinesterase (prolongs succ) Roc, Vec biliary excretion (prolongs) Larger vol of distribution Consider cis -not dependent on hepatic metabolism

Factors that change SVO2

Decrease: ↑consumption, ↓delivery Increase: ↓consumption, ↑delivery

Causes of decreased EtCO2 - ↓CO2 production

Decreased BMR (↓VO2) Increased anesthetic depth Hypothermia Decreased pulmonary blood flow Decreased cardiac output Hypotension Pulmonary embolism V/Q mismatch Medication side effect

Diastolic heart failure

Decreased Ventricular compliance Heart is unable to relax and fill properly Can hear S4

Factor that affects onset of action

Depth of the block

Order of NDNMB potentiation of volatiles

Des > Sevo > Iso > N20 > propofol

substantia gelatinosa

Descending inhibitory pathway begins in the periaqueductal gray and the rostroventral medulla -the dorsal region of the spinal cord where both fast and slow pain fibers synapse with sensory nerves on their way to the brain

Conditions that impair reliability of pulse oximetry

Decreased perfusion Dysfxnal Hgb Altered optical characteristics Non-pulsatile flow Motion artifact

Ascites

Decreased renal perfusion Altered intrarenal hemodynamics Enhanced proximal and distal sodium reabsorption Often an impairment of free water clearance

Hypoxic ventilatory response

Decreases in PO2 stimulate the carotid bodies (CNIX) to increase ventilation - peripheral chemoreceptors Stimulus: PaO2 < 60 carotid bodies are more sensitive to changes in O2, aortic bodies are more sensitive to BP

what circumstances mimic cerebral ischemia?

Deep anesthesia Hypothermia Hypocarbia

Ankle block dermatomes

Deep peroneal = web b/w 1st & 2nd toe Tibial = Heel Sural = lateral aspect of the foot Superficial peroneal = dorsum of the foot Saphenous = medial aspect of the foot

Methods to reduce postop myalgia

Defasciculating dose of NDNMBs (3-5min b/f succ) 1. Roc 2mg, Atricurium 1.5mg, Vec (increase Succ dose to 1.5-2mg/kg when using) -give 3-5 minutes b/f Succ -do not use a defasciculating dose on pt's w/ pre-existing muscle weakness (myasthenia gravis) 2. Lidocaine 1.5mg/kg, NSAIDs, 0.3mg (not opioids)

Anesthetic considerations for acute hepatitis

Delay surgery if possible until stabilized Use Iso = best for hepatic bld flow (never halothane) Avoid PEEP (decreased hepatic drainage) normocapnea liberal use of IV fluids

Acceptable response to nerve stimulator (interscalene)

Deltoid (shoulder abduction) Pectoralis major (arm internal rotation) Biceps (forearm flexion) Triceps (forearm extension) Any twitch of the hand or arm

Affect of adding opioids to neuraxial block

Denser block -they also diffuse into the systemic circulation and bind to opioid receptors in the body

Which value is most susceptible to error with oscillatory BP measurement

Diastolic BP

Methods to reduce cerebral edema

Diuretics Hypertonic fluid Corticosteroids (NOT for TBI)

Gabapentin s/e

Dizziness Somnolence Can produce seizure in patients w/ seizure history, need a taper

Semi-open circuit

Does not allow rebreathing of exhaled gas FGF is higher than minute ventilation No rebreathing w/ a reservoir

Parkinson's pathophysiology

Dopaminergic cells in the basal ganglia are destroyed TOO MUCH ACETYLCHOLINE + TOO LITTLE DOPAMINE = overstimulation of basal ganglia Increased Ach in the basal ganglia stimulates GABA activity in the thalamus (suppresses the thalamus) Overactivity of the extrapyramidal system

Sensory tracts

Doral column: Cuneatus & Gracilis = Fine touch & proprioception Tract of Lissauer: Part of spinothalamic tract Lateral spinothalamic tract: Pain & Temp Ventral spinothalamic tract: Crude touch & pressure

primary factors that determine spinal spread

Dose and baricity

Neostigmine dose, onset, duration, metabolism/elimination, best anticholinergic pairing

Dose: 0.02 - 0.07 mg/kg Onset: 5-15 min Duration: 45-90 min Metabolism/Elimination: Renal 50%, Liver 50% Pairing: Glycopyrrolate

Pyridostigmine dose, onset, duration, metabolism/elimination, best anticholinergic pairing

Dose: 0.1-0.3 mg/kg Onset: 10-20 min Duration: 60-120 min Metabolism/Elimination: Renal 75%, Liver 25% Pairing: Glycopyrrolate

Edrophonium dose, onset, duration, metabolism/elimination, best anticholinergic pairing

Dose: 0.5-1 mg/kg Onset: 1-2 min Duration: 20-60 min Metabolism/Elimination: Renal 75%, Liver 25% Pairing: Atropine

Narcan Administration

Draw up 0.4mg Narcan (1ml) with 3ml sterile water. Give 1 ml at a time. Stop when respiratory depression diminishes. Try to keep dose as low as possible so pt sill has some analgesia affects.

Zero order kinetics

Drug elimination with a constant amount metabolized regardless of drug concentration -> constant amount per time -there is more drug than enzymes -examples: ASA, phenytoin, alcohol, warfarin, heparin, theophylline

Lipophilic drug

Drug that Vd exceeds total body water (>0.6L/kg or >42L) Will require a higher does because a lot of it is lost from the plasma into fats

Hydrophilic drug

Drug that Vd is less than total body water (<0.6L/kg) Will require lower dose because it down not go into fats so there is more in the plasma

hypoglycemia causes

Drugs: Insulin, Sulfonylureas, Beta-blockers, Toxins: Ethanol Severe liver disease Altered physiology associated w/ gastric bypass Sepsis Insulin-secreting tumor of the islets of Langerhans (an insulinoma)

hepatocyte synthesis functions

Procoagulents, Anticoagulents, fibrinolytics, thrombopoetin, plasma proteins, pseudocholinesterase does not synthesize: immunoglobulins, VWF, factor III, factor VIII (produced by sinusoidal cells in liver)

Inadequate mask ventilation (cause, steps to take)

Due to decreased compliance and increased resistance Place an OA/NA 2 handed BMV Intubate or place SGA

Meninges

Dura - Outermost layer - Thick • Provides most of the protection for the CNS Arachnoid - Thin • Closely associated to the dura matter • Under this layer is the subarachnoid space Pia - Thin •Directly covers the spinal cord

Causes of Altered Optical Characteristics

Dyes such as Methylene Blue, indocyanine green, and indigo carmine Nail polish (esp black, blue, and green) External light

Dynamic Compliance

Dynamic = Movement Compliance of the lung/chest wall during air movement

Phenytoin s/e

Dysrhythmias w/ Hypotension (if rate > 50mg/min) Gingival hyperplasia Aplastic anemia Cerebellar vestibular dysfxn - nystagmus, ataxia Stevens-Johnson syndrome Birth defects

Benefit of partial agonists

Produce analgesia with less risk of respiratory depression Low risk of dependence Can be used in patients who cannot tolerate a full agonist

re-entry pathway

Re-entry describes the process where a single cardiac impulse can move backwards and excite the same part of the myocardium over and over this can precipitate a reentry tacharrhythmia

clearance is inversely proportional to

Half-life Concentration of drug in central compartment

Paget's disease

Excess osteoblastic and osteoclastic activity tinnitus, bone pain, enlargement of bone, thick bones Cause: Excessive parathyroid hormone or calcitonin deficiency Can cause peripheral nerve entrapment NO vascular involvement

Classification of brain waves

EEG provides data about activity of the cerebral cortex EEG can help monitor cerebral ischemia

Capacity limited elimination

ER < 0.3 Clearance dependant on liver ability to extract drug from the blood. changes in hepatic enzyme activity or protein binding affect the clearance of these drugs enzyme induction -> ↑clearance enzyme inhibition -> ↓clearance

Flow limited elimination

ER > 0.7 drugs with a high extraction ratio clearance is dependent on liver blood flow ↑liver blood flow -> ↑clearance

Intermittent opioid dosing

Each time you give a bump of an opioid you are pushing higher above the apnea line. Doing this puts you at the highest point above the apnea line at the end of the case. If you front load instead it will be high in the beginning, and lower at the end of the case.

Reconstitution of Dantrolene

Each vial contains 20mg of Dantrolene + 3g Mannitol reconstituted w/ 60mL sterile water (Do not use normal saline, it takes longer to dissolve)

Dose Response Curve

Effect as it increases in relation to potency allow you to determine (1) Affinity-chemical attachment to receptor (potency) (2) Efficacy (3) Variability (4) Slope First part of the slope=potency not enough to cause clinical effect Last part of curve = 100% effect so effect cannot increase anymore left shift -> ↑affinity for receptor -> ↑potency -> lower dose required right shift -> ↓affinity for receptor -> ↓potency ->higher dose required

Hydrocone

Effectiveness varies on pt's genetically determined mu receptor binding. CYP2D6

Percentages of oxygen utilization in the brain

Electrical activity = 60% Cellular integrity = 40%

Circuit created by electrocautery

Electrosurgical generator -> Active cable -> Active electrode -> Return pad -> Return cable

secondary hypertension

Elevated BP with a specific cause

Twitch monitor placement - Recovery

Emergence (Extubation) Muscle: Adductor Pollicis or flexor hallucis Function: Adducts thumb Nerve: Ulnar or posterior tibial

High-risk procedures for cardiac morbidity and mortality (>5% risk) per AHA guidelines

Emergency surgeries Open aortic surgery Peripheral vascular surgery Long surgical procedures w/ significant volume shifts and/or blood loss.

CNS changes w/ liver dx

Encephalopathy = accumulation of toxins (Nitrogen compounds= ammonia) breaks down the blood brain barrier Increased levels of GABA ↑Cerebral uptake of benzos

General RLN injury causes

External pressure from ETT or LMA parathyroid or thyroid surgery Neck tumor Neck extension

Examples of decreased complince

Endobronchial intubation Pulmonary edema Pleural effusion Tension pneumothorax Atelectasis Chest wall edema Abdominal insufflation Ascites Trendelenburg position Inadequate muscle relaxation

Recommendations for block placement/catheter removal: low molecular weight Heparin

Enoxaparin, Dalteparin, Tinzaparin Before block placement: Prophylactic (Once daily): Hold 12h Therapeutic (twice daily): Hold 24h Before catheter removal: Hold 12h After catheter removal: Hold 2h After single shot block Prophylactic (Once daily): Hold 6-8h Therapeutic (twice daily): Hold 24h

Neuraxial recommendations w/ low molecular weight heparin

Enoxaparin, Dalteparin, Tinzaparin: b/f block placement (prophylactic dose) hold 12h, (therapeutic dose) hold 24h b/f removing catheter hold 12 h After removing catheter hold 2h

How to prevent burns at the site of the return pad

Ensure the entire surface of the return pad is in contact w/ patient's skin (not over bony prominences or metal implants) Ensure the electrolyte gel on the return pad is not dried out

Epicardial v transvenous leads

Epicardial leads stimulate surface of the heart Transvenous leads stimulate cardiac chambers (Atrium and ventricles)

Epidural

Epidural Caudal

What is the best monitor to determine the amount of FGF required to prevent rebreathing w/ a Mapleson circuit

EtCO2

Most sensitive indicator of MH

EtCO2 rise (out of proportion to minute ventilation)

Factors that stimulate insulin secretion

Glucose, mannose, fructose (hyperglycemia) Amino acids, ↑FFA GI/digestive hormones Acetylcholine (parasympathetic stimulation) β-adrenergic stimulation

Phase III (C-D)

Exhalation of alveolar gas

Phase I (A -B)

Exhalation of anatomic dead space

Phase II (B-C)

Exhalation of anatomic dead space + alveolar gas

Pharynx (overall structure and 3 compartments)

Extends from the base of the skull to the cricoid cartilage Nasopharynx, oropharynx, and hypopharynx

Causes of decreased frequency on EEG

Extreme hypercarbia Hypoxia Cerebral ischemia Hypothermia anesthetic overdose opioids

laryngospasm etiology

Extubated while lightly anesthetized Recent URI Tobacco exposure GERD Peds

FA/FI Curve

FA = the partial pressure of the gas in the alveoli FI = the concentration of the gas leaving the vaporizer

Guidelines for diagnosis of DM

FPG ≥ 126 mg/dL or, random glucose level > 200 mg/dL

What factors reduce ventricular compliance?

Factors that decrease compliance Age > 60 Ischemia Pressure overload hypertrophy (aortic stenosis or HTN) Hypertrophic obstructive cardiomyopathy Pericardial pressure (increased external pressure)

Vestibular folds

False vocal cords, around the vocal folds/true vocal cords

2 fascias above the femoral nerve

Fascia Iliaca Fascia Lata

SpO2 sites from most to least responsive

Fast = ear, nose, tongue, esophagus, forehead Middle = finger Slow = Toe The closer monitoring is to central circulation the faster it is.

Causes of increased rate of rise

Faster induction -> faster wash in or slower uptake ↑ WASH IN: ↑ FGF ↑ alveolar ventilation ↓FRC ↓time constant ↓anatomic dead space ↓UPTAKE: ↓CO ↓solubility ↓Pa/Pv difference

Adductor canal block

Femoral nerve block lower in the thigh Femoral nerve is beneath the sartorius muscle in this location Analgesia for knee surgery without blocking the quadricep muscle (ambulation after surgery)

Agent that causes the most ↑ in biliary pressure

Fentanyl (Meperidine causes the least)

Order of context sensitive half times for Remi, Fentanyl, Alfentanil, and Sufentanyl

Fentanyl (longest) > Alfentanil > Sufentanyl > Remifentanil (shortest)

Bullard Laryngoscope

Fiberoptic device for indirect laryngoscopy Useful for pt's w/ small mouth openings (Pierre Robin, Treacher Collins). Mouth must be able to open minimum of 6mm. Do not need axis alignment to use (cervical spine injuries) Disposable attachment for tall pt's. Must be retrieved from mouth.

Acceptable response to twitch monitor (supraclavicular)

Finger twitch

Cell body locations of three-neuron pain pathway

First order: dorsal root ganglia Second order: dorsal horn Third order: thalamus

Preparations for MH patient

Flush machine w/ high flow O2: 20-100min Replace all external components: circuit, CO2 absorbent, breathing bag Remove vaporizers Monitor in PACU for 1-4 hours

Anesthetic mgmt for hypertrophic cardiomyopathy

For ↑HR & ↑contractility: BB's, CCB (diltiazem, verapamil) For ↓Preload: Phenylephrine, vol resuscitation For ↓afterload: Phenylephrine

Interventions for decreased O2 supply

For ↓HR: Anticholinergic, pacing For HoTN: Vasopressor, ↓ anesthesia depth For ↑PAOP: Nitro, inotrope (decrease preload or ↑contractility)

Drugs metabolized by Alkaline Phosphatases

Fospropofol ie. this is prodrug is metabolized by alkaline phosphatase to form the active drug propofol

When to treat PVCs

Frequency > 6/min, polymorphic, or come in runs of 3 or more Tx focuses on reversing underlying cause Symptomatic PVC tx: lidocaine 1-1.5mg/kg

Larynx blood supply

From branches of the thyroid arteries Upper 1/2 of larynx Superior laryngeal artery: branch of the superior thyroid artery off the external carotid Lower 1/2 of larynx Inferior laryngeal artery: branch of the inferior thyroid artery off the subclavian artery

Patients at risk of aspiration

Full stomach GERD Hiatal hernia NG Morbid obesity DM Pregnancy Use of narcotics

Acinus

Functional unit of liver lobule -hepatocytes surrounding a central vein

Phase 1 drug metabolism

Functionalization reactions Oxidation Reduction Deamination Dealkylation methylation Sulfoxidation hydrolysis most anesthetics undergo phase 1 metabolism (midazolam, diazepam, codeine, phenobarbital) Anesthetics ↓ hepatic bld flow which slows metabolism of drugs

DKA

Glucose: > 250 mg/dl pH < 7.3 Serum Bicarbonate < 18 mmol/L Serum Osmolality + Ketonemia: ++ Mental obtundation: Present Hypovolemia: Present

HHS

Glucose: > 600 mg/dl pH > 7.3 Serum Bicarbonate >15 mmol/L Serum Osmolality ++ (>330 mOsm/L) Ketonemia: Normal or slight+ Mental obtundation: Present Hypovolemia: Present

Catabolic hormones that oppose insulin

GH Cortisol Epinephrine Glucagon (defend against hypoglycemia)

Recommendations for block placement/catheter removal: Herbal therapies

Garlic, Ginkgo, Ginseng Proceed if pt is not on any other blood thinners

Neuraxial recommendations w/ Herbal therapies

Garlic, Ginko, Ginseng Proceed if pt not on other blood thinners

GI complications from RA

Gastic ulcerations d/t steroids and NSAIDs

immunosuppressive drugs

General immunosuppressants: steroids Calcineurin inhibitors: Cyclosporine, Tacrolimus Antimetabolites: Imuran, Mycophenolate Inhibitors of TOR (Target of Rapamycin) Antilymphocyte Antibodies Polyclonal Antibodies Monoclonal Antibodies

Anesthetic mgmt of AH

General or spinal anesthesia is preferred (better than epidural) Epidural can be used for laboring mother but it does not inhibit the sacral root to the same degree Treat HTN w/: removal of stimulus, deepen anesthetic, rapid acting vasodilator (nipride) Treat bradycardia w/ atropine or glyco Do not give chronotropic agents Lidocaine jelly on catheters does not help Succ is contraindicated May present in postoperative period after anesthesia wears off

Risk of perioperative MI in pt's w/ previous MI

General population: 0.3% MI > 6 mo ago: 6% MI 3 - 6 mo ago: 15% MI < 3 mo ago: 30% greatest risk is w/in 30 days of acute MI

Factors that increase the risk of MH

Geography (Wisconsin, Nebraska, West Virginia & Michigan) Male Youth

When is ICP monitoring indicated?

Glasgow coma score </= 7

Global, Cortical and Subcortical cerebral blood flows

Global: 45-55mL/100g tissue/min Cortical: 75-80mL/100g tissue/min Subcortical: 20mL/100g/tissue/min

innervates anterior epiglottis

Glossopharyngeal (IX) - also posterior 1/3 of tongue, vallecula, soft palette,

drugs that relax the sphincter of oddi

Glucagon Glycopyrrolate Atropine Naloxone Nitroglycerine

Dexamethasone (Decadron)

Glucocorticoid - reduces serotonin in brain Adult: 4-8mg IV, Child 150mcg/kg (max: 8mg) May produce hyperglycemia postoperatively in diabetics, may delay wound healing, masks infx. Similar efficacy to zofran.

metabolic processes

Gluconeogenesis: The formation of glucose from lactate, pyruvate, amino acids, and glycerol (liver) Glycogenolysis: breakdown of glycogen into glucose (liver) Lipolysis: breakdown of triglycerides to FFA acids and glycerol -stimulated by enzyme hormone-sensitive lipase

Meds to avoid w/ hypokalemic periodic paralysis

Glucose containing solutions Potassium wasting diuretics Beta-2 agonist

Meds that are safe w/ hyperkalemic periodic paralysis

Glucose containing solutions Potassium wasting diuretics Beta-2 agonist NDNMB's Acetazolamide

Drugs to avoid w/ cardiac tamponade

Halogenated agents propofol Thiopental high dose opioids Neuraxial anesthesia

s/s intracranial HTN

H/A N/V Papilledema Focal neurologic deficit ↓LOC seizure coma

Drug considerations for carcinoid syndrome

H1 & H2 blockers used to ↓ effects of histamine Avoid histamine releasing agents: morphine, thiopental, and atricurium Avoid sympathomimetic agents: ketamine and ephedrine Treat hypotension with alpha-receptor agonist: phenylephrine Deep sedation: Des and Sevo preferred Serotonin antagonists, antihistamines -Pretreat with Octreotide (somatostatin analog): 100 mcg SQ 2 -3 times daily -Somatostatin: suppress the release of tumor products

Thiazide diuretics MOA

HCTZ, metolazone, indapamide, chlorthalidone MOA: Inhibits Na-Cl transporter in distal convoluted tubule

Myocardial oxygen demand is a function of

HR Preload Afterload Contractility

Bradycardia

HR < 60 bpm increased vagal tone is freq cause 1st line tx: Atropine: 0.5mg IV -Underdosing (<0.5mg) can cause paradoxical bradycardia Symptomatic tx: Transcutaneous pacing Other potential medications: Dopamine & Epi Tx for BB/CCB overdose: Glucagon (50-70mcg/kg)

Highest to lowest cardiac oxygen consumption

HR ~ Pressure work > Contractility > Wall Stress > Volume work

BP during stroke

HTN is common after ischemic stroke Hypotension decreases CPP and worsen ischemia target pressure should maintained under 185/110

Complications w/ Narcan

HTN, CVA, Pulmonary edema, Cardiac arrest, VT/VF

Alkanes

Halothane Chloroform

What is the definitive test for MH

Halothane contracture test

Dantrolene MOA

Halts Ca+ release from the RyR1 receptor Prevents Ca+ entry into the myocyte

Hard vs soft palate

Hard -Stationary Soft -Posterior 1/2 of oral cavity -Rises during eating to prevent aspiration -Sleep/paralytic can cause it to obstruct the nasal passage

Mallampati 4

Hard palate only - uvula not visualized

McGrath MAC video laryngoscope

Has a video display mounted on the handle -Sizes 2, 3, 4 correspond to Mac blades

HELP position

Head elevated laryngoscopy position Used for obese pt's ramping or elevating of head and chest to align the sternum and external auditory meatus on the same horizontal plane.

Whipple (Pancreaticoduodenectomy)

Head of pancreas & duodenum, portion of jejunum, distal stomach, & distal section of common bile duct are removed; biliary system, pancreatic system, & GI tract reconstructed -Choleodochostomy: The establishment of a fistula into the common bile duct -Pancreaticogastrojejunostomy(Pancreatic gastrojejunostomy)

Methods to increase venous outflow

Head positioning = avoid flexion and extension, avoid head down, head up >30mmHg increases outflow Reduce intrathoracic pressure (PEEP, bucking, coughing, straining)

Preoxygenation before RSI

Healthy patient: Four maximal breaths Patient with lung disease: 3-5 minutes

Convection heat loss

Heat loss due to air currents

Eschmann Introducer Bougie Intubating Stylet

Helps facilitate intubation of a very anterior glottis with a coude tip. Cormack and Lehane score of 3. Feeling the clicks of the tracheal rings confirms placement. If no clicks extend to carina for "hold up" sign. ie you will not meet resistance if you're in the esophagus.

Neurogenic shock

Hemodynamic derangement associated with spinal cord injury instability is greatest with injuries to the cervical or upper thoracic cord. the higher the injury the greater the degree of instability Can be confused w/ hypovolemic shock

Liver dx risk factors for mortality

High Child-Pughs core Presence of ascites Elevated serum creatinine Pre-op upper GI bleed High ASA rating

Effect of high venous pressure on the brain

High venous pressure decreases cerebral venous drainage, increasing cerebral volume (ICP)

Type of cuff recommended for ETT

High volume low pressure -Decreases risk of mucosal damage

RF for post-Succ myalgia

Highest risk: young adults (women>men) undergoing ambulatory surgery, low normal activity level Lowest risk: elderly, pregnant, peds

Lumbar L2-L5 inj

Hip surgery Lower extremity obstetric analgesia

VIA pharmacologic effect and target region for Amnesia

Hippocampus: Memory formation Amygdala: Emotion, pain response, stress response

Succinylcholine CV effects

Histamine release Stimulation autonomic ganglia -> tachycardia Stimulation M2 receptor -> bradycardia

opioid immunologic effects

Histamine release (morphine, meperidine, codeine) Inhibition of cellular and humoral immune fxn Suppression of natural killer cell fxn

Deep brain stimulation for Parkinson's

Hold levodopa to allow for better mapping Burr hole awake, lightly sedated (do not use GABA agonists - precedex, opioids) precordial doppler for air embolism d/t sitting position SBP < 140

Conduction velocity

How fast an electrochemical impulse propagates along a neural pathway

Disease that causes increased sensitivity to Succ

Huntington's Chorea

Arteriodilators

Hydralazine (all arterial), nipride (arterial & veins equal) MOA: ↑NO -> Vasodilation, ↓SVR

Anti-rheumatic drug MOA

Inhibit tumor necrosis factor (TNF), interleukin-1 & 6 Inhibits T cells & B lymphocytes (Immunosuppresant) Methotrexate, cyclosporine, etanercept methotrexate causes liver dysfxn & suppresses bone marrow Cyclosporine prolongs duration of Succ

What conditions increase the risk of failure to capture?

Hyper and hypo kalemia Hypocapnea (intracellular K+ shift) Hypothermia MI Fibrotic tissue build up around leads Antiarrhythmic meds

Are the nerves for the infraclavicular block hyper or hypoechoic

Hyperechoic (they are hypoechoic for scalene and supraclavicular)

Conditions that increase specific gravity

Hyperglycemia Uremia High protein content advanced age Colder temperatures

Conditions that increase specific gravity

Hyperglycemia Uremia High protein content Advanced age Colder temperature

Blood sugar during stroke

Hyperglycemia = glucose is converted to lactic acid during ischemic stroke which causes acidosis which destroys brain tissue

Presence of extrajunctional receptors predisposes patients to what?

Hyperkalemia

Contraindication for Succ in peds

Hyperkalemic rhabdomyolysis: d/t undiagnosed muscular dystrophy (DMD). Can lead to cardiac arrest and sudden death

Hyperaldosteronism clinical findings

Hypertension Hypokalemia Alkalosis fatigue/weakness Paresthesia Nocturnal polydipsia, polyuria

Stroke RF

Hypertension (most important) Smoking DM HLD Excessive alcohol intake elevated homocysteine levels

Cardiac complications w/ DM

Hypertension, CAD, Autonomic nervous system dysfunctions Ischemic heart disease: most common cause of perioperative mortality in the diabetic patient

Late signs of MH

Hyperthermia Cola-colored urine Coagulopathy Muscle rigidity

Serotonin syndrome symptoms

Hyperthermia, mental status changes, hypertension, tachycardia; Hyperreflexia: myoclonic jerking, tremors; Seizures, death

The axis shifts as a consequence of?

Hypertrophy Conduction block Physical change in position of the heart

The mean electrical vector tends to point towards

Hypertrophy (more tissue undergoing depolarization)

How to offset the vasodilatory effects of VIA

Hyperventilating, propofol, opioids, barbituates

Causes of decreased EtCO2 - ↑Alveolar ventilation

Hyperventilation Inadequate anesthesia Metabolic acidosis (if spontaneous ventilation) Medication side effect

Methods to ↓ CBF

Hyperventilation (↓PaCO2 ~30-35mmHg) Avoid hypoxemia (keep PaO2 > 60mmHg Avoid vasodilators (NTG, nipride) Drugs that reduce CMRO2 are ok (thiopental, propofol) Avoid extreme HTN - BP above the autoregulation curve contributes to edema

What does a high CVP indicate

Hypervolemia Reduced ventricular compliance Increase intrathoracic pressure

Anesthetic concerns w/ liver dx

Hypoglycemia Coagulopathies (Vitamin k factors) PLT sequestration and thrombocytopenia (Splenomegaly secondary to portal HTN) ↓ protein synthesis and protein oncotic pressure= third spacing-> ↑ vol of distribution, (must consider for medication dosing) Varices (careful w/ NG/OG) Pos Pressure ↓ venous return

electrolyte disturbances that prolong QT

Hypokalemia, Hypocalcemia, hypomagnesemia

other things that decrease MAC

Hypotension (MAP < 50) Hypoxia Anemia (<4.3 O2/dL blood) CPB Metabolic acidosis Hypo-osmolarity Pregnancy -> Postpartum (24-72h)

Temp control for periodic paralysis

Hypothermia must be avoided at all costs Pt's are kept normothermic even during CPB

Liver txp intraop complications

Hypothermia, Hyperkalemia, hypocalcemia, Oliguria, Hypotension, Hypertension, post reperfusion syndrome Expect massive amounts of blood loss keep UOP minimum of 0.5 mL/ kg/hour

Patient factors that potentiate NMB's

Hypothermia: ↓metabolism & ↓ clearance Female gender: more sensitive to NMB's

Causes of increased EtCO2 - ↓Alveolar ventilation

Hypoventilation CNS depression Residual neuromuscular blockade COPD High spinal anesthesia Neuromuscular disease Metabolic alkalosis Medication side effect

I GET SMASHED - Acute Pancreatitis causes

I - idiopathic G - gallstones E - EtOH T - Trauma S - steroids M - mumps, malignancy A - autoimmune S - scorpion sting H - Hypertriglyceride, hypercalcemia E - ERCP D - drugs

Cranial Nerve Functions

I. (Olfactory) Some: Sensory Function II. (Optic) Say: Sensory Function III. (Oculomotor) Money: Motor Function IV. (Trochlear) Matters: Motor Function V. (Trigeminal) But: Both Sensory and Motor Function VI. (Abducens) My: Motor Function VII. (Facial) Brother: Both Sensory and Motor Function VIII. (Vestibuloclear) Says: Sensory Function IX. (Glossopharyngeal )Big: Both Sensory and Motor Function X. (Vagus) Brains: Both Sensory and Motor Function XI. (Accessory) Matter: Motor Function XII. (Hypoglossal) More: Motor Function

cranial nerves

I. Olfactory II. Optic III. Oculomotor IV. Trochlear V. Trigeminal VI. Abducens VII. Facial VIII. Vestibulocochlear IX. Glossopharyngeal X. Vagus XI. Accessory XII. Hypoglossal

Class I antiarrhythmic drugs

IA: moderate depression of phase 0, prolongs phase 3 repolarization (K+ channel block -> ↑QT) ex. Quinidine, Procainamide, Disopyramide IB: Weak depression of phase 0, shortened phase 3 repolarization ex. Lidocaine, Phenytoin IC: Strong depression of phase 0, little effect on phase 3 ex. Flecainide, Propafenone

functions of CN III, IV, VI

III: Eye movement (all except cross eyed and lateral) & pupil constriction IV: Eye movement (cross eyed) VI: Eye movement (lateral)

Portal HTN tx

IV Vasopressin or somatostatin Vasopressin: splanchnic vasoconstrictor, constriction of mesenteric arterioles, reducing inflow to the portal venous system 0.1 -0.4 Units per minutes -can infuse nitro to avoid systemic HTN Octreotide (somatostatin analog) ↓ gut motility and venous return to portal circulation 50 mcg/ hour infusion Compression of varices: Triple lumen Sengstaken-Blakemore tube Direct Sclerotherapy: Inj of sclerosing agent directly into bleeding vessel and/ or adjacent tissue

R->L shunt effect on induction of IV and volatiles

IV: Faster (blood bypasses lungs) Volatile: Slower, and worse with insoluble gases (Des) Effect Iso the least (more of the agent is dissoved in the blood)

Effect of increased cardiac output on induction

IV: increases the speed of induction Volatile: decreases the speed of induction (Alveoli don't build up concentration as fast b/c agent is being removed too quickly (think about it being watered down)

Cranial Nerves that innervate muscles of pharynx, larynx, soft palate

IX: Glossopharyngeal X: Vagus XI: Spinal accessory

Desflurane chemical characteristics

Identical to Iso except instead of a chlorine it has another fluorine making it fully fluorinated This causes: ↓potency (↓oil: gas solubility) -> ↑MAC ↑vapor pressure (↓intermolecular attraction) - requires heated vaporizer ↑ resistance to biotransformation (↓metabolism)

Acid

If pH > pKa ionized predominates If pH = pKa non-ionized = ionized If pH < pKa non-ionized predominates

Base

If pH > pKa non-ionized predominates If pH = pKa non-ionized = ionized If pH < pKa ionized predominates

Interpretation of Pethick test

If the reservoir bag deflates, the inner tube is patent and safe to use. If the reservoir bag stays slightly inflated there is an obstruction in the inner tube and its not safe to use.

Pancreatitis anesthetic considerations

Ileus (aspiration precautions) Glucose monitoring -Electrolyte disorders (hypercalcemia, hypomagnesemia, hypokalemia, hypochloremic metabolic alkalosis) -Frequent coagulation draws: Potential blood product and crystalloid resuscitation -Pulmonary complications (pleural effusions) -Maintain UOP 0.5-1 mL/kg/hr -Give colloid & bld over crystalloid -heparin drip -give sodium mannitol prior to reperfusion -Broad-spectrum abx -Immunosuppressives given

When does PAOP overestimate LVEDV

Impaired LV compliance (ischemia, diastolic dysfxn) MV disease (stenosis or regurg) L -> R cardiac shunt Tachycardia PPV PEEP COPD Pulmonary HTN Non west zone III placement

EKG changes with DMD

Impaired cardiac conduction -> ST & short PR interval Increased R wave amplitude in lead I and deep Q waves in the limb leads

Respiratory affects of Neuraxial anesthesia

Impairment of intercostal muscles (inspiration & expiration) Impaired abdominal muscles (cough, clear secretions) Reduced accessory muscle function Loss of proprioception input from the chest can cause dyspnea Apnea is usually the cause of cerebral hypoperfusion NOT phrenic nerve paralysis

Pathophysiology of neurogenic shock

Impairment ot cardioaccelorator fibers (T1-T4) Decreased SNS tone -> vasodilation -> venous pooling -> decreased CO & BP Impairment of sympathetic pathways from hypothalamus to blood vessels -> inability to vasoconstrict or shiver -> hypothermia

Chemical Bonds

In order of decreasing strength -Covalent -Ionic -Hydrogen -Hydrophobic -van der wahls Drugs bind their receptors thru these

Macintosh blade inserted ____

In vallecular fold -Lifting motion elevates the epiglottis and uncovers the vocal cords Child: 2 Adult: 3-5

What to do if CO2 absorbent becomes exhausted in the middle of a case and it cannot be changed (ie your EtCO2 does not return to baseline)

Increase FGF (5-8mL/min), this converts the semi closed circle system to a semi-open circuit If this doesn't work than it is a problem with the unidirectional valve

What should be done if the valve cannot immediately be fixed

Increase FGF to turn the system into semi-open which prevents rebreathing

Electrolyte effects on MAC

Increase MAC: Hypernatremia Decrease MAC: Hyponatremia No Effect: Potassium and magnesium

Age effect on MAC

Increase MAC: infants 1-6 months (Sevo is the same for neonates & infants Decreases MAC: Older age (↓ 6% per decade after 40) & prematurity

Parkinson's treatment

Increase dopamine levels or decrease Ach in basal ganglia levodopa (L-dopa/ Sinemet) & Carbadopa Levodopa is metabolized to DA in the blood and cannnot cross the BBB. Carbadopa is a decarboxylase inhibitor so it inhibits the metabolism of levodopa to DA, allowing levodopa to make it into the brain

Methods to decrease CSF

Increase drainage (Ventric) Acetazolamide and lasix decrease CSF production

AAA law of laplace correlation

Increase of diameter increases the risk of rupture because it lead to increased wall stress

MOA of urinary retention with neuraxial opioids

Inhibition of sacral parasympathetic tone more common in men more common with neuraxial opioids over IV/IM

Gabapentinoids (Gabapentin, Pregablin) MOA, metabolism

Inhibition of the alpha 2 delta subunit of voltage gated calcium channels in the CNS - ↓ excitatory nt release -not a GABA agonist and does not get metabolized to GABA Excreted unchanged in the kidneys, do not cause hepatic induction Also useful for neuropathic pain

Causes of increased EtCO2 - ↑CO2 production

Increased BMR (↑VO2) MH Thyrotoxicosis Fever Sepsis Seizures Laparoscopy Tourniquet or vascular clamp release Bicarb administration Anxiety Pain Shivering Increased muscle tone (after NMB reversal) Medication side effect

Disadvantages of Mapleson Circuit

Increased apparatus dead space Requires high FGF to prevent rebreathing Loss of heat and humidity Inefficient use of inhaled anesthetics Risk of environmental pollution Unrecognized kinking of fresh gas hose in Bain circuit (Use Pethick test)

Body temp effect on MAC

Increases MAC: Hyperthermia Decreases MAC: Hypothermia

Wisconsin blade

Increases the visual field and decreases the possibility of trauma -Strait spatula, flange expands slightly toward the distal blade

ERCP (endoscopic retrograde cholangiopancreatography)

Indications: biliary or pancreatic ductal disorder, Biliary or pancreatic drainage, Biopsy, Bile or pancreatic juice collection, Mapping of the pancreatic duct before intended surgery MAC, conscious sedation or GA Glucagon given to relax sphincter of Oddi: 0.4 -1 mg IV

Axillary indications and landmarks

Indications: forearm & hand Landmarks: axillary artery pulse, coracobrachialis muscle 9 (musculocutaneous nerve passes thru it), humerus

Mallampati classification

Indirect method of relating the size of the base of the tongue to the oral cavity

SLE exacerbation

Induced by stress or drug exposure PISSED CHIMP P = Pregnancy I = Infection S = Surgery S = Stress E = Enalapril D = D-penicillamine C = Captopril H = Hydralazine I = Isoniazid M = Methyldopa P = Procainamide

Brain wave changes during General Anesthesia

Induction -> ↑beta activity Light anesthesia -> ↑beta activity Theta and Delta waves predominate during GA Deep anesthesia produces burst suppression At 1.5-2 MAC GA causes isoelectricity

How is exhaled gas measured

Infrared Absorption Spectrophotometry -each gas absorbs a different wavelength of infrared light. -measures the partial pressure of the gas

Radiation heat loss

Infrared heat loss

Troponin T - initial, peak, and return to baseline

Initial elevation: 3-12h Peak elevation: 12-48h Return to baseline: 5-14 d

Creatinine Kinase MB (CK-MB) - initial, peak, and return to baseline

Initial elevation: 3-12h Peak elevation: 24h Return to baseline: 3-5d

Troponin I - initial, peak, and return to baseline

Initial elevation: 3-12h Peak elevation: 24h Return to baseline: 5-10 d

Factors that cause the CO to be underestimated

Injectate volume too high Injectate solution too cold

Factors that cause the CO to be overestimated

Injectate volume too low Injectate solution too hot Partially wedged PAC Thrombus on tip of PAC

ETT size - what does it mean

Inner diameter size -Most important in resistance to fresh gas flow -Effects resistance much more than the length of the tube

Sevoflurane Metabolism

Inorganic fluoride ion production

Phase IV (D-E)

Inspiration of fresh gas that does not contain CO2

Signs of laryngospasm

Inspiratory stridor Suprasternal and supraclavicular retraction during inspiration "Rocking horse" appearance of the chest wall Increased diaphragmic exersion Lower rib flailing

Examples of open circuit

Insufflation Simple face mask Nasal Cannula Open drop

What artery is most likely to be inadvertently injected with each brachial plexus block

Interscalene: Vertebral Supraclavicular: Subclavian Infraclavicular: Subclavian or axillary Axillary: Axillary

Factors that affect CVP

Intravascular volume Venous tone Right ventricular compliance

Larynx muscles

Intrinsic -Provides functional movement of cartilages and the vocal cords Extrinsic -Moves larynx as a whole in the neck superiorly and inferiorly

Phase 1 metabolism: modification

Introduction of a polar functional group or modification of an existing functional group in a drug molecule such that it becomes more polar - water-soluble -Oxidation: removes electrons (donates an oxygen) -reduction: adds electrons (accepts an oxygen) -hydrolysis: adds water to split compound -Usually entails the P450 system -metabolite can be active

Volatile anesthetics chemical structures

Iso is the only one w/ a chlorine Halothane is the only one with a bromineV

Blood:gas coefficient

Iso: 1.46 Sevo: 0.66 Des: 0.42 N2O: 0.46

VIA effects on CSF

Iso: No effect on production, ↑absorption Des: Little to no effect on production, no effect on absorption Sevo: ↓ production, unknown effect on absorption

Type and number of Halogens

Isoflurane: 5 fluorine atoms, 1 Chloride Desflurane: 6 fluorine atoms Sevoflurane: 7 fluorine atoms Des and Iso contain chiral carbons - Sevo does not

How does metabolic acidosis effect CBF

It has no effect because H+ cannot pass BBB (only CO2), so respiratory acidosis increases CBF

How does an incompetent unidirectional valve change ventilation

It increases dead space

Oil/gas partition coefficient

It is a measure of lipid solubility. Lipid solubility - correlates strongly with the potency of the anesthetic. Higher the lipid solubility - potent anesthetic. Iso: 91 Sevo: 47 Des: 19 N2O: 1.4 (Can never reach a full Mac)

Conditions that impair venous drainage

Jugular compression secondary to improper head positioning Increased intrathoracic pressure secondary to coughing or PEEP Vena cava thrombosis Vena cava syndrome

Preferred treatment for atypical pseudocholinesterase variants

Keep the patient intubated and sedated until Succ has worn off. Can give whole blood, FFP transfusions, or purified human cholinesterase but waiting is the safest.

Drugs that are safe w/ cardiac tamponade

Ketamine* N20 Benzos opioids Local anesthesia is anesthetic of choice for pericardiocentesis

Popliteal block US landmarks

tibial and common peroneal nerve are superior to the popliteal vein and artery.

Sacral Plexus

L4 - S4

Tuffier's Line

L4-L5 interspace (correlates with the iliac crest)

Which spinal nerves are most resistant to local anesthetics

L5 & S1 = largest nerves It is also the largest interspace

Largest spinal roots and most resistant to LA's

L5 and S1 This is also the largest interspace in the vertebral column

Lemon law airway assessment

L=Look externally (0-4pts) E=Evaluate 3-3-2 (0-3pts) M=Mallampati (I-IV) O=Obstruction (0-1pt) N=Neck mobility (0-1pt) Score 0-9 points, higher score means possibly more difficult airway

Factors that do not increase the risk of TNS - Transient Neurological Symptoms causes

LA concentration or baricity LA glucose concentration Early ambulation

LMA size in relation to what size of ETT can fit through it

LMA 1: 3.5 LMA 1.5: 4.0 LMA 2: 4.5 LMA 2.5: 5.0 LMA 3: 6.0 LMA 4: 6.0 LMA 5: 7.0 LMA 6: 7.0

How does expiration affect SV?

LV filling decreases (d/t the decreases RV filling on inspiration - transit time) Decreased LV filling decreases SV

6 complications of hypertension

LV hypertrophy Ischemic heart disease (increased myocardial work) CHF Aortic aneurysm Stroke End stage renal disease

Causes of non-pulsatile flow

LVAD CPB

relative refractory period of ventricular AP

Last 2/3 of the T wave

Second Degree Heart Block Type I etiology

Last P cycle is dropped b/c it comes during the absolute refractory period defect occurs in the AV node Cause: structural conduction deficit, MI, BB, CCB, digoxin, sympatholytic agents Asymptomatic tx: monitor Symptomatic tx: Atropine

Disease/conditions that reduce Pseudocholinesterase activity

Late stage pregnancy Atypical PChE Severe liver disease Chronic Renal disease organophosphate poisoning Burns Neoplasm Advanced age malnutrition (Obesity increases activity)

Motor tracts

Lateral corticospinal tract: Limb motor Ventral corticospinal tract: Posture motor

Caudal technique

Lateral or prone Sims position Landmarks: iliac spines & sacral hiatus 22-25g needle, 20g IV Placing needle above S2-3 increases risk of dural puncture Do not use air for loss of resistance (air embolism)

Which 2 leads do you look at to determine mean electrical vector

Lead I & aVF The axis represents the direction of the mean electrical vector

Best leads to monitor myocardial ischemia

Leads V3, V4, V5

most common cause of right HF

Left HF

TIPs fluid management

Lg amounts of albumin crystalloid not advised LR exacerbates liver failure secondary to the breakdown of bicarbonate in the liver Sodium retention limits amounts of NS Mannitol to maintain urine output of at least 50 mL/hour (avoid Lasix) Complications to watch for include liver laceration, gallbladder perforation, oliguric renal failure (secondary to contrast dye) and stent embolization

Airway exchanger

Long, thin, flexible hollow tube that maintains access to the airway post extubation. Used to manage extubation of difficult airway.

What causes the sensation of dyspnea with neuraxial anesthesia

Loss of proprioception in the chest

Advantages of Mapleson Circuits

Low resistance (good for peds) Convenient Easily scavenged Bain circuit prevents heat loss

Benefits of non-cutting tip

Lowers risk of PDPH More tactile feel Needle less likely to deflect Less likely to injure the cauda equina

Pneumocytes

Lung cells Type 1: surface area for gas exchange, tight junctions Type 2: produce surfactant. capable of reproduction. Can produce type 1 cells Type 3: Marchophages

VIA affect on redheads

MAC is increased by 19% d/t mutations in the melanocyte stimulating hormone receptor and an increased production of pheomelanin

Selegiline

MAO-B inhibitor = inhibits the metabolism of dopamine in the basal ganglia

Hepatic artery perfusion pressure

MAP - Hepatic vein pressure

Occular perfusion pressure

MAP - IOP

Most common cause of postop death of AAA repair

MI

Causes of systolic HF

MI Valve incompetency Dilated cardiomyopathy

Causes of diastolic heart failure

MI valve stenosis HTN Hypertrophic cardiomyopathy Cor Pulmonale Obesity

Spinal cord protection strategies (clamp to ascending aorta)

Necessary when clamp time exceeds 30min -Moderate hypothermia (30-32) -CSF drainage (less pressure) -Proximal hypertension -Avoid hyperglycemia -SSEP and MEP -Partial CPB -Drugs: steroids, CCB, &/or Mannitol

Most common causes of acute spinal cord injury

MVC, fall, assault, sports injury.

Kupfer cells

Macrophages in the liver that clean the blood of bacteria b/f it goes to the vena cava

Hemodynamic goals for tamponade

Maintain HR & SR Maintain or increase Preload Maintain or increase contractility Maintain afterload (compensates for ↓SV and CO

Function of upper airway dilator muscles

Maintain airway patency Tensor palatine = opens nasopharynx Genioglossus = opens oropharynx Hyoid muscle = opens hypopharynx

What to do if evoked potentials decrease during surgery

Maintain good BP, volume expansion, and tranfusion for anemia

ETT size and depth for adults

Male: 7.0-8.0mm, 23cm Female: 6.5-7.0mm, 21cm

Which Mapleson circuit is the most efficient for spontaneous ventilation?

Mapleson A

Which Mapleson is worst for controlled ventilation

Mapleson A

Which Mapleson is worst for spontaneous breathing

Mapleson B

Which Mapleson circuit is best for controlled ventilation?

Mapleson D

Which Mapleson does not have a reservoir bag or APL valve

Mapleson E (Ayre's T piece)

Examples of Semi-open circuit

Mapleson circuit (FGF dependent on design) Circle system (FGF > Minute ventilation)

PaCO2 levels at which maximal vasodilation and vasoconstriction occur

Maximal vasodilation -> PaCO2 80-100mmHg Maximal vasoconstriction -> PaCO2 25mmHg

Peak Inspiratory Pressure (PIP)

Maximum pressure in patient's airway during inspiration -Affected by both resistance & chest wall compliance

Treatment for Diastolic HF

May need to increase preload to stretch non-compliant ventricle Keep afterload elevated to preserve CPP to perfuse thick myocardium Contractility is usually normal Keep HR slow to normal to increase diastolic time and CPP

extraction ratio

Measure of how much drug is delivered to clearing organ vs how much drug is removed by the organ ER 1.0: 100% of delivered drug is removed ER 0.5: 50% of delivered drug is removed ER = (arterial conc. - venous conc.)/arterial conc

NMB ED95

Measure of potency The higher the ED95, the lower the potency, the faster the onset. Low potency -> more drug needed. The higher volume of drug equates to more drug available to interact with receptors -> faster onset

MAC of volatile agents

Measure of potency (solubility) Iso: 1.2 Sevo: 2 Des: 6.6 N2O: 104

ST segment

Measured at J point - in relation to PR segment (isoelectric) Consider MI if elevation of depression > 1mm Elevation can also be caused by Hyperkalemia or endocarditis

Beta angle

Measured at point D should go straight down because patient should be inhaling fresh gas

Epidural needles/catheters

Measurements/Depth • Needle: 1cm markings: Indicate where Loss of resistance (LoR) occurs -Depth to the epidural Space • Catheter Markings: 1cm markings • Double/Triple/Quad Markings = multiples of 5

esophageal doppler

Measures the velocity of blood flow in the descending thoracic aorta - calculates the SV of blood in the descending aorta

partial agonist

Medication that produces a weaker, or less efficacious, response than an agonist. They have a ceiling to their effect - Buprenorphine *If you give on top of a full agonist it reduces the efficacy of the full agonist (antagonizes it). Will have a lower amount of pain relief than if the partial agonist had been given on its own. -lower dependence potential -used in patients who can not tolerate a full agonist

Dorsal column peripheral receptors

Meissner's corpuscles= 2 point discriminative touch, vibration Merkel's discs= Continuous touch Ruffini's Endings= proprioception, prolonged touch and pressure Pacinian corpuscles= vibration

Which opioid should be avoid with a MAO-i

Meperidine Its is a weak serotonin reuptake inhibitor so co-administration can lead to serotonin syndrome

Opioid that causes anticholinergic like effects

Meperidine = has atropine-like ring structure mydriasis, tachycardia, dry mouth

Which opioid can cause seizures

Meperidine d/t its metabolite normeperidine

Movement of neck on ETT

Neck Flexion: Tube goes in deeper / nose to chest, tip moves toward carina Neck Extension: Tube come out / nose away from chest, tube moves away from carina (this can be enough to extubate an infant) Lateral head movements will also move the tube away from the carina.

Extrajunctional receptors reaction to succ

More sensitive - receptors stay open longer (more K+ leak) = this is why succ can cause hyperkalemia

From most Hydrophilic to Lipophilic opioids

Morphine > Hydromorphone > Meperidine > Fentanyl > Sufentanil

Hydrophilic opioid profile

Morphine, Demerol, Dilaudid Slower onset more rostral (brain) spread more respiratory depression (early and late) stays in CSF longer (wider band of analgesia, less systemic absorption) higher incidence of N/V, pruritis

Order of potency for NMB's

Most -> Least potent (Least potent will be fastest) Cisatracurium Vecuronium Mivacurium = Pancuronium Atracurium Succ Rocuronium

Branches

Most Alcoholics Must Really Urinate Musculocutaneous: C5-C7 -> lateral cord Axillary: C5-C6 -> Posterior cord Median: C5-T1 -> Lateral & medial cord Radial: C5-T1 -> Posterior cord Ulnar: C8 - T1 -> Medial cord

POISE study finding

Most Perioperative MI's occur w/in 48h of surgery

Orthodromic AVRT

Most common (90%) Atrium -> AV node -> Ventricle -> Accessory pathway -> Atrium Narrow QRS Tx: Block conduction at the AV node = increase AV refractory period: Vagal maneuvers, Amiodarone, Adenosine, BB, Verapamil, Cardioversion

AV nodal reentrant tachycardia (AVNRT)

Most common tachyarrhythmia associated w/ WPW

Corticospinal tract (Motor)

Most important motor pathway Also known as the pyramidal tract Pyramids are formed by the corticospinal neurons as they run through the medulla All toher motor tracts are called extrapyramidal b/c they don't pass through the pyramids

Artery of Adamkiewicz

Most important radicular artery Perfuses the anterior spinal cord in the thoracolumbar region Most commonly originates on the left side b/w T11-12 In 75% of the population it arises from T8-12 In another 10% it arises from L1-2

Brain auditory evoked potentials

Most resistant to the affects of anesthetics, so any agent can be used

Methadone MOA

Mu receptor agonist NMDA receptor antagonism Monoamine reuptake inhibition

opioid receptors

Mu: beta endorphin, met and leu enkephalin Kappa: Dynorphin Delta: met and leu enkephalin ORL-1 receptor: nociceptin

Drugs that increase MAC

Need more gas -chronic alcoholism -Acute amphetomine intoxication -Acute cocaine intoxication -MAOI's -Ephedrine -Levodopa

Transtracheal block

Needle advanced caudally through the cricothyroid membrane. Patient inhales during injection, this causes cough which send the local anesthetic up through the cords

Superior laryngeal block

Needle injection at the inferior border of the greater cornu of the hyoid bone. Aspiration of Air: Needle is to deep

Factors that influence compliance

Muscle tone Degree of lung inflation Alveolar surface tension Amount of interstitial lung water Pulmonary fibrosis

Which nerve is most likely to be missed with an axillary block?

Musculocutaneous

Opioids - epidural

Must use higher volumes than spinal opioids to account for the spread from the epidural space across the dural cuff. • Fentanyl 50-100mcg Bolus • Morphine 2-5mg (Apex) our notes say 3mg • >3mg has one of the highest incidences in resp depression in closed claim cases, morphine is more hydrophilic than fentanyl so it stays in the CSF and ascends toward brain

Disease that causes resistance to Succ

Myasthenia gravis

Succ can cause muscle contractures w/ which disease?

Myotonic dystrophy

s/s of cirhosis

N/V: Metabolic alkalosis & hypokalemia Pulmonary vasodilation R to L shunt hypoxemia Splenomegaly, esophageal varices (↑back pressure) encephelopathy (↑nitrogen/ammonia) Hepato-renal syndrome

Gases

N2O Cyclopropane Xenon

N2O vitamin B12 inhibition

N2O irreversibly inhibits B12 which inhibits methionine synthase (enzyme required for folate metabolism and myelin production) S/E: Megaloblastic anemia (bone marrow suppression) Neuropathy Immunocompromise Impaired DNA synthesis teratogenicity (lacking evidence) spontaneous abortion (avoid in first 2 trimesters) Homocysteine accumulation Increased risk of side effects in pt's w/ chronic b12 deficiencies: pernicious anemia, vegan, alcoholism, recreational N2O use

Most common cause of perioperative allergic rxn

NMB's (11% of allergic rxns in the US)

Site of action for N2O and Xenon

NMDA inhibition Potassium 2P channel stimulation (They do not stimulate GABA)

TNS treatment

NSAIDs opioids trigger point injections

Venodilators

NTG, Nipride MOA: ↑NO -> Vasodilation, ↓preload

Channel dysfxn associated w/ Hyperkalemic periodic paralysis

Na+ channelopathy

Which opioid antagonist can be used to treat alcohol withdrawal or maintain recovering opioid abusers?

Naltrexone

Treatment for opioid induced pruritis

Narcan (benzo's will not work b/c it is not related to histamine release)

hyperkalemia affects on EKG (in order - early to late)

Narrow peaked T wave Short QT Wide QRS Low P amplitude Wide PR Nodal block (junctional) Sine wave fusion of QRS & T -> VF or asystole

Reversal agent effects on pseudocholinesterase

Neostigmine and pyridostigmine inhibit pseudocholinesterase (not edrophonium)

Renal complications of SLE

Nephritis w/ proteinuria

Aprepitant (Emend)

Neurokinin 1 (NK1) antagonist Dose: 40mg PO Long duration -PDNV Oral undergoes first pass in liver. IV is formulated as the prodrug since it does not go thru the liver first. Blocks neurokinin receptors in the nucleus of solitary tract which are involved in visceral fxn. (oncology)

Rolapitant (Varubi)

Neurokinin 1 (NK1) antagonist Dose: 90mg PO Approved for chemo N/V. Cannot take more than once q2weeks.

Vasospasm prevention / treatment

Nimodipine Triple H therapy: hemodilution (HCT 27-30), hypervolemia, hypertension) daily transcranial doppler exams Maintain CPP Liberal hydration: supports MAP & CPP, causes hemodilution which decreases blood viscosity and cerebrovascular resistance

Types of nicotinic receptors

Nn: presynaptic (nerve cell) Nm: postsynaptic (muscle cell)

Is the OR power supply grounded

No

Is there an increased risk of MH w/ osteogenesis imperfecta?

No

Are opioids associated w/ apoptosis in animal models

No Drugs that are: N2O, etomidate

Can you adequately measure EtCO2 with a rigid bronchoscope

No the rigid bronchoscope does not provide a secure airway - risk of aspiration is present throughout the procedure Use lowest FiO2 possible if using for laser surgery

Isoelectricity

No activity Very deep anesthesia and death

epidural differential block

No autonomic differential block sensory is 2-4 dermatomes higher than motor

Order of blockade for epidural

No autonomic differential blockade Sensory is 2-4 dermatomes higher than motor

Hypermagnesemia on EKG

No effect unless very high: Heart block & cardiac arrest

Hypomagnesemia on EKG

No significant effect unless very low: Long QT -> Torsades

Guillain-Barre Anesthetic mgmt

No succ - risk of hyperkalemia Increased sensitivity of nondepolarizers ANS dysfxn -> hemodynamic instability exaggerated response to indirect sympathomimetics (upregulation of postjunctional adrenergic receptors) Immobility -> increased risk of DVT Regional anesthesia is controversial

What distinguishes a Mapleson circuit from closed or semi-closed

No unidirectional valve No CO2 absorber

Does a masseter spasm after Succ require case to be cancelled

No, only if there are other signs of MH

myasthenia gravis

Normal Ach production, autoimmune related antibodies (IgG) destroy receptors on the neuromuscular jxn Symptoms become worse later in the day or w/ exercise, get better w/ rest thymus gland plays a key role and its removal can improve condition

Chronic diastolic HF

Normal EDV, ESV ↑ EDP ↓ SV ↑ LV Mass Concentric hypertrophy

How to determine axis deviation

Normal: I & aVF positive Left: I positive, aVF negative (Leaving each other) Right: I negative, aVF positive (Returning) Extreme right: I & aVF negative

Upper airway components (5 parts)

Nose Mouth Pharynx Hypopharynx Larynx

extrinsic laryngeal muscles that depress the larynx

Omohyoid Sternohyoid Sternothyroid

Cranial Nerve Pneumonic

On Old Olympus Towering Top, A Fin and German Viewed A Hopp

Cranial Nerves

On old olympus towering top a finn and german viewed a hop I. Olfactory II. Optic III. Oculomotor IV. Trochlear V. Trigeminal VI. Abducens VII. Facial VIII. Vestibulocochlear IX. Glossopharyngeal X. Vagus XI. Accessory XII. Hypoglossal

Spinal blood supply

One Anterior Spinal Artery • Supplies 2/3 of the Anterior Cord • Originates from the Vertebral Artery Two Posterior Spinal Arteries • Originate off the Cerebellar Arteries • Supplies 1/3 of the Posterior Cord Segmental Spinal Arteries • Artery of Adamkiewicz - Supplies the anterior lower 2/3 of the cord Veins • 3 Anterior Spinal Veins, 3 Posterior Spinal Veins • communicate the epidural veins (plexus of batson)

How to re-dose NMB if sugammadex has already been given?

Only possible if 4mg/kg or less was the dose < 4h since reversal -> Roc: 1.2mg/kg > 4h since reversal -> Roc: 0.6mg/kg, Vec: 0.1mg/kg

What ligaments are transversed w/ the paramedian approach

Only the ligamentum flavum

Twitch monitor placement - Onset

Onset (Intubation) Muscle: Obicularis Oculi Function: Closes eyelid Nerve: Facial

Withdrawal timeline for Fentanyl and Meperidine

Onset: 2-6h Peak: 6-12h Duration: 4-5 days

Withdrawal timeline for Methadone

Onset: 24-48h Peak: 3-21 days Duration: 6-7 weeks

Withdrawal timeline for Morphine & Heroin

Onset: 6-18h Peak: 36-72h Duration: 7-10 days

Cranial nerve most likely to be affected by a pituitary tumor

Optic nerve

Phase 1 metabolism

Oxidation, reduction, hydrolysis

EKG: mechanical events

P wave: Atrial depolarization begins PR interval: Atrial depolarization complete QRS: Atrial repolarization; Ventricular depolarization begins ST segment: Ventricular depolarization complete T wave: Ventricular repolarization begins After T wave: Ventricular repolarization complete

How can you tell the tip is NOT in zone 3?

PAOP > PADP Nonphaseic PAOP tracing Inability to aspirate blood from PA line when in the wedged position

RLN injury left side only

PDA ligation (Patent ductus arterius) Left atrial enlargement (mitral stenosis) Aortic arch aneurysm Thoracic tumor

What cardiac lesions need to be corrected b/f an LVAD can be placed

PFO aortic insufficiency Tricuspid regurgitation

What causes Torsades de pointes

POINTES Phenothizines Other meds Intracranial bleeding No known cause Type 1 antiarrhythmics Electrolyte disturbances Syndromes

R on T phenomenon

PVC lands on 2nd half of T wave (relative refractory period)

Dynamic measures of pulse contour

PVI, SVV, SPV, PPV predict volume responsiveness when measurement is greater than 13-15%

Why should the PA catheter tip be positioned in lung zone 3

Pa > Pv > PA there is a continuous column of blood between the catheter tip and the LV

PaCO2 to EtCO2 gradient

PaCO2 is higher than EtCO2 Normal is 2-5mmHg

PaO2 effect on CBP

PaO2 < 50-60mmHg causes cerebral vasodilation and increases CBF (edema). When PaO2 is > 60mmHg it has no effect on CBF

Pacemaker Designation

PaSeR Position 1: Pa: Chamber Paced Position 2: Se: Chamber Sensed Position 3: R: Response Position 4: Programmability

Complications of NIBP measurement

Pain Neuropathy (radial, ulnar, median) measurement errors Limb ischemia compartment syndrome Bruising Petechiae Interference with IV medication delivery

DM comorbidities

Pancreatectomy Cystic fibrosis Severe pancreatitis endocrine conditions: Cushing syndrome, Glucagonoma, Pheochromocytoma, Acromegaly Steroid-induced diabetes Gestational diabetes

Kussmal's sign

Paradoxical RISE in JVP with inspiration (JVP should normally fall w/ inspiration). Seen in cardiac tamponade and constrictive pericarditis.

What are the parasympathetic and sympathetic innervation of the gut

Parasympathetic: Vagus Sympathetic: T5-L2

Extrajunctional receptors

Pathologic variant of ACh (nicotinic) receptors that have become denervated -resemble receptors present in fetal development = these are replaced by the adult subtype once innervation takes place -proliferate after muscle injury/disease/burns -the alpha 7 receptor is depolarized by both succ and its metabolite choline (choline makes a significant contribution to hyperkalemia)

Result of an incompetent valve

Patient rebreathes gas

Absolute contraindication to neuraxial anesthesia

Patient refusal

Which patient group should not receive pancuronium

Patients w/ hypertrophic cardiomyopathy = tachycardia causes LVOT occlusion -> reduces flow through the AV

presentation of mild hyperkalemia

Peaked t-wave and prolonged PR interval. Can progress to VF or asystole

Endogenous pain modulation pathway

Periaqueductal grey -> Rostroventral Medulla -> Substantial gelatinosa

RA cardiac complications

Pericardial effusion or tamponade Aortic regurgitation d/t dilated Aortic root Valvular fibrosis Coronary artery arteritis

CV complications of SLE

Pericarditis Raynaud's syndrome Hypertension Conduction defects Endocarditis

Definition for patient cardiac risk

Perioperative MI, CHF, or death

Nervous system complications from RA

Peripheral neuropathy d/t nerve entrapment

Cauda Equina Syndrome definition, symptoms, and treatment

Persistent Paralysis of the nerves of the Cauda Equina -Neurotoxicity is the result of exposure to high concentrations of LA's. S/S: Lower Extremity Weakness, Bowel/Bladder dysfxn Treatment is supportive

How do you test the Bain circuit

Pethick test

Phase I vs Phase II block

Phase I: the absence of fade & post-tetanic potentiation, constant but diminished response to double burst stimulation (Succ) Phase II: presence of fade & post-tetanic potentiation (NDNMB)

Interscalene Complications

Phrenic nerve paralysis (COPD) Horner's syndrome (Stellate ganglion - C7) Epidural/spinal (needle too medial) Seizures (vertebral artery) C6 neuropathy (intraneural inj) RLN injury (hoarseness) Pneumo (cupola of lung higher on R) Hypotensive bradycardia episode(Bezold Jarish reflex d/t sitting position)

7 factors that warrant prophylactic abx (to prevent endocarditis)

Previous infective endocarditis Prosthetic heart valve Unrepaired cyanotic congenital heart disease Repaired congenital heart defect < 6 months ago Repaired congenital heart defect w/ residual defects that have impaired endothelialization at the graft site Heart transplant w/ valvuloplasty

Relative contraindications for caudal anesthesia

Pilonidal cyst Abnormal superficial landmarks Hydrocephalus Intracranial tumor Progressive degenerative neuropathy

Relative contraindications to caudal anesthesia

Pilonidal cyst Abnormal superficial landmarks Hydrocephalus Intracranial tumor Progressive degenerative neuropathy

Pulmonary complication of RA?

Pleural effusion Restrictive ventilation pattern -Diffuse interstitial fibrosis -Costochondral involvement limits chest wall expansion

Acute Pancreatitis CV complications

Pleural effusions Arrhythmias s/s mimicking acute myocardial infarction Thrombophlebitis Cardiac depression Acute pancreatitis also predisposes patients to development of: ARDS, DIC

Most common SLE problems

Polyarthritis and dermatitis

VIA pharmacologic effect and target region for Autonomic modulation

Pons & Medulla: Control center for autonomic reflex

Mechanisms responsible for ascites

Portal hypertension = ↑hydrostatic pressure-> transudation of fluid across the intestine into the peritoneal cavity Hypoalbumenia Seepage of protein-rich lymphatic fluid from the serosal surface of the liver secondary to distortion and obstruction of lymph channels in the liver water & sodium retention (↑RAAS)

Acetylcholinesterase

Positioned around Nn and Nm nicotinic receptors. Hydrolyzes ACh almost immediately after binding. Ensure muscle contractions are discreet and not sustained.

MOA of blockage

Primary: Spinal roots Bind to sodium channels in the inactive state stopping potentiation

What do SSEP's test?

Posterior cord Posterior spinal arteries Sensory function *does not monitor motor function

Anterior border of the epidural space

Posterior longitudinal ligament

Landmarks for Larson's maneuver

Posterior: mastoid process Superior: skull base Anterior: Ramus of the mandible

Class III antiarrhythmic drugs

Potassium channel blockers Prolongs Phase 3 (↑QT) ↑effective refractory period ex. Amiodarone, Bretylium

Potassium vs calcium effect on membrane potentials

Potassium: raises RMP (more excitable) Calcium: raises threshold potential (less excitable)

Meperidine

Potency Ratio: 0.1 Analgesia Dose: 100mg Anesthetic Dose: NA Duration of action: 2-4h pKa: 8.5 (7% nonionized) Protein biding: 70% Vd: 2.6 metabolized to a CNS toxic metabolite. Not recommended for admin >24h or for renal dx or elderly. Stimulates Mu & Kappa receptors

Morphine Sulfate

Potency Ratio: 1 Analgesia Dose: 10mg Anesthetic Dose: 1-5mg/kg Duration of action: 3-5h pKa: 7.9 (23% nonionized) Protein biding: 35% Vd: 2.8 metabolism: liver, conjugated and eliminated by kidney as a phase 2 product

Alfentanil (Alfenta)

Potency Ratio: 10-20 Analgesia Dose: 500-1000mcg Anesthetic Dose: 100-200mcg/kg Duration of action: 0.25-0.4h pKa: 6.5 (89% nonionized) Protein biding: 92% Vd: 0.6 Metabolism: Liver CYP3A4

Fentanyl (Sublimaze)

Potency Ratio: 100 Analgesia Dose: 100mcg Anesthetic Dose: 50-100mcg/kg Duration of action: 1-1.5h pKa: 8.4 (8.5% nonionized) Protein biding: 84% Vd: 4 Metabolism: CYP3A4

Remifentanil (Ultiva)

Potency Ratio: 100 Analgesia Dose: infusion only (0.1-1 mcg/kg/min) Anesthetic Dose: infusion only Duration of action: 2-5 min metabolism: nonspecific esterase, only opioid not affected by liver dx pKa: 7.2 (58% nonionized) Protein biding: 95% Vd: 0.39 dosed at lean body weight d/t metabolism Mu agonist

Heroin

Potency Ratio: 2 *causes the most euphoria

Hydromorphone (Dilaudid)

Potency Ratio: 5 (apex says 7) Analgesia Dose: 2mg Anesthetic Dose: NA

Sufentanil (Sufenta)

Potency Ratio: 500-1000 Analgesia Dose: 10-20mcg Anesthetic Dose: 5-20mcg/kg Duration of action: 0.8-1.3h pKa: 8 (20% nonionized) Protein biding: 93% Vd: 2 *most potent opioid, do not give unless you don't plan to extubate after the case.

Opioid potency

Potency is extremely variable b/c of people's differences in pain perception and tolerance. Animal studies: tail click test and hot plate test

Precursors of endogenous opioids

Pre-proopiomelanocortin = Endorphins = Mu Pre-Enkephalin = Enkephalin = Delta Pre-dynorphin = Dynorphins = Kappa

Dexmedetomidine

Precedex infusions to prolong duration

Factors that can cause SLE exacerbation

Pregnancy Stress Infection Surgery

Situations that exacerbate myasthenia gravis

Pregnancy Infx Electrolyte abnormalities Surgical & pyschological stress Aminoglycoside abx

Airflow obstruction capnography

Prolonged upstroke with increased alpha angle COPD, bronchospasm, kink

Pyridostigmine ____________ the duration of Succ

Prolongs It impairs the efficacy of pseudocholinesterases

Effect of renal failure on reversal agents

Prolongs both reversal and NMB's so dosing is the same.

Awake extubation: pros and cons

Pros: •Airway reflexes intact •Ability to maintain patent airway •Decreased risk of aspiration Cons: •Increased CV and SNS stimulation •Increased coughing •Increased intracranial, intraocular, and intraabdominal pressure

Deep extubation: pros and cons

Pros: •Decreased CV ad SNS stimulation (CAD) •Decreased coughing and airway irritation (Asthma) Cons: •Ineffective airway reflexes •Increased risk of airway obstruction (OSA) •Increased risk of aspiration

Astrocytes

Provide structural and metabolic support for neurons. Most abundant type of cell in CNS Repair neurons after injury

Difficult airway algorithm

Provides the practitioner four end-points: 1. Intubation awake or asleep 2. Intubation emergent or nonemergent 3. Approach supraglottic or subglottic 4. Airway access surgical or nonsurgical

key s/e of neuraxial opioids

Pruritis* N/V respiratory depression urinary retention

Tolerance

Pt requires higher dose of drug to achieve effects d/t receptor desensitization and ↑ synthesis of cAMP - NOT d/t enzyme induction

Basic urine favors

Reabsorption of basic drugs Excretion of acidic drugs BBB: Basic drugs are Better absorbed in Basic urine You can alkanize the urine to eliminate acidic drugs (bicarb, acetazolemide)

Causes of increased EtCO2 - Equipment malfunction

Rebreathing Exhausted CO2 absorbant Unidirectional valve malfunction Leak in breathing circuit Increased apparatus dead space

Complications while floating PA

Pulmonary artery rupture RBBB Complete HB (if pre-existing LBBB) Dysrhythmias

Compliant airspaces

Pulmonary blebs bowel pneumoperitoneum sulfa hexafluoride bubble in the eye (compromises retinal perfusion) Air bubbles in the blood

Testing branches of the brachial plexus

PusheR, Pull-eM, Pinch ME, Pinch U Radial: Extend arm against resistance Musculocutaneous: Flex arm against resistance Median: Pinch web b/w thumb and index finger Ulner: Pinch pinky finger

Too short of an oral airway = ____

Pushes posterior tongue against the post pharyngeal wall = obstruction/trauma

absolute refractory period of ventricular AP

Q wave to first third of T wave

Factors that affect Mixed venous oxygen saturation (SvO2)

Q: Cardiac output (L/min) VO2: oxygen consumption (mL O2/min) Hgb: g/dL SaO2: Loading of hgb in arterial blood (%) Normal: 65-75%

Vector of depolarization

QRS complex -A positive deflection occurs when the vector of depolarization travels toward the positive electrode -A negative deflection occurs when the vector of depolarization travels away from the positive electrode -A biphasic deflection occurs when the vector of depolarization travels perpendicular to the positive electrode

difference between QT interval and QTc

QT interval varies w/ HR, so QTc is the corrected QT interval Prolonged QT interval Men > 0.45 sec Women > 0.47 sec Some texts say . 0.40sec

Molecular structure of reversal agents

Quaternary Amines - they do not pass through the blood brain barrier or the placenta *Except physostigmine which is a tertiary amine

Cutting tip needle

Quinke Pitkin Requires less force

Cutting needles

Quinke, Pitkin • can pierce cauda equina root w/out knowing • Cutting needles can deviate • give less perceptive feedback pops • PDPH rates are 3x higher • BOTTOM LINE: Try not to use cutting needles

What part of the EKG does IABP deflation correlate with

R wave

Ethers

R-O-R (ether bridge) Desflurane Isoflurane Sevoflurane Enflurane Methoxyflurane Ether

What does an increased beta angle indicate?

Rebreathing specific to a faulty unidirectional valve (ie - not increased d/t exhausted CO2 absorber)

Nociceptors

Receptors that sense pain, respond to substance P, bradykinin.

Nerve block for the trachea below cords (Transtracheal)- nerve and location

Recurrent laryngeal nerve 3-5mL LA through cricothyroid membrane

Ways that the pulse ox can be used to monitor perfusion

RUE: innominate artery compression during mediastinoscopy Toe to monitor perfusion in lithotomy position Limb perfusion following a fracture Brachial artery compression during shoulder surgery

Acceptable response to twitch monitor (axillary)

Radial: finger or wrist extension Ulnar: ulnar deviation Median: finger flexion Musculocutaneous: bicep twitch

4 mechanisms of heat transfer in the OR

Radiation (60%) Convection (30%) Evaporation (20%) Conduction (<5%)

Brachial plexus - medial to lateral

Randy Travis Drinks Cold Beer Roots Trunks Divisions Cords Branches

How do opioids cause skeletal muscle rigidity

Rapid IV bolus Stimulation of CNS -> resistance to ventilation is called to chest wall rigidity (but its really due to muscles in the larynx)

Steady state

Rate of administration = rate of elimination -the compartments have equilibrated, although there may be different amounts in different compartments

Innervates trachea

Recurrent laryngeal nerve (X)

Components present in Mapleson circuit

Reservoir bag Fresh gas inlet Corrugated circuit tubing APL Valve Mask

opioid effects on thermoregulation

Resets hypothalamic temperature set point -> ↓core temp

If ↑PIP w/ no change in PP

Resistance has increased or Inspiratory flow rate has increased

Acute pericarditis treatment and anesthetic mgmt

Resolves spontaneously Drugs to relieve pain: salicylates, oral analgesics, corticosteroids

Early respiratory complication of scoliosis

Restrictive ventilatory defect -↓FEV1 & FRC -normal FEV1/FVC ratio Decreased lung volumes: VC, TLC, RV, FRC Decreased chest wall compliance

Pulmonary complications of SLE

Restrictive ventilatory defect Pulmonary hypertension Interstitial lung disease w/ impaired diffusing capacity Pleural effusion Recurrent pulmonary emboli

Protamine

Reverses via neutralization reaction (acid/base complex) 1mg protamine reverses 100 units of heparin Protamine overdose can cause prolonged ACT

AchE inhibitors MOA

Reversibly inhibits AchE, increasing the concentration of Ach at the neuromuscular junction allowing it to better compete with NMB's for nicotinic binding. It does not decrease the amount of NMB present - it still needs to be eliminated from the body

Laboratory findings w/ RA

Rheumatoid factor ↑C-reactive protein ↑erythrocyte sedimentation rate

Conditions associates with development of PVCs

SNS stimulation MI Valve dx Cardiomyopathy Prolonged QT Hypokalemia Hypomagnesemia Digitalis toxicity Caffeine Cocaine Alcohol Mechanical irritation (central line insertion)

Distance from SVC and right atrium to catheter tip

Right atrium: 0 - 10cm Right Ventricle: 10 - 15cm Pulmonary artery: 15 - 30cm PAOP position: 25 - 35cm

Branches of Recurrent laryngeal nerve

Right-subclavian Left-aortic arch

Bronchi Mainstem

Right: 2.5cm long, 25 degree takeoff Left: 5cm long, 45 degree takeoff

What structures does the RLN wrap around on the right and left side

Right: Subclavian artery Left: Aorta

Space between vocal folds

Rima glottidis, goes to the trachea

Order of efficacy for sugammadex in NDNMB's

Roc > Ven > Pancuronium

Low hepatic extraction drugs

Rocuronium diazepam Methadone Thiopental Theophylline Phenytoin

Aminosteroid compounds metabolism/elimination

Rocuronium: No metabolism. Elimination: Mostly Biliary - no hepatic metabolism, a little renal Vecuronium: Hepatic metabolism. Elimination Renal > liver, but pretty equal Pancuronium: Hepatic metabolism. Elimination Renal >> liver

Misc that prolong QT

Romano-Ward syndrome Timothy syndrome Hypertrophic cardiomyopathy Subarachnoid hemorrhage Bradycardia

interscalene block level

Root level

posterior femoral cutaneous nerve

S1-S3 Sensory: Posterior thigh (not sciatic)

Coccygeal

S4-Co Pudendal Inferior anal Perineal

Order of conduction system

SA node -> Internodal tracts -> AV node -> Bundle of His -> Bundle Branches -> Purkinje Fibers

Femoral triangle borders

SAIL lateral border = Sartorius medial border = Adductor longus Superior border = Inguinal Ligament

BP range for aortic cannulation

SBP < 100 SBP: 90-100 or MAP < 70

Changes is SBP and DBP moving from aortic root to periphery

SBP increases & DBP decreases, PP widens, MAP remains constant Aortic root: SBP lowest, DBP highest, PP narrowest Dorsalis pedis: SBP highest, DBP lowest, PP widest

Intraoperative BP during aneurysm surgery

SBP: 120-150mmHg High normal BP is required to perfuse collateral vessels while clamp is on If no clamp is use, controlled hypotension may be requested to prevent aneurysm rupture

BP regulators

SNS (Vasopressors), RAAS, vasopressin

What type of circuit is a Mapleson

Semi-open or non-rebreather

Vagus nerve supply and branches

Sensation to the airway below the epiglottis -2 branches innervate the hypopharynx: Superior laryngeal nerve Recurrent laryngeal nerve

Disorders that often require splenectomy

Sickle cell anemia Thalassemia Primary or secondary hypersplenism

What does a Cobb angle of 100 indicate

Significant gas exchange impairment and higher risk of postop pulmonary complications

Patient State Index monitor

Similar to BIS Target range for GA: 25-50

Epiglottis

Single leaf like cartilage, sits above the glottic opening (to the larynx) -Closes during swallowing -Attached to the upper border of the hyoid bone

What causes the BBB to dysfunction

Sites of tumors, injury, infection, or ischemia

Spinal Positioning

Sitting • Easier to achieve interspinous space • Easier to assess midline • Easier to assess landmarks • Patients need to "round out" back

Eye complications from RA

Sjogren's sydrome - risk of corneal abrasion

From skin to spinal cord

Skin Subcutaneous tissue Supraspinous ligament Interspinous ligament ligamentum flavum (epidural space) dura mater (subdural space) arachnoid mater (subarachnoid space) pia mater spinal cord

List the structures a needle passes through for an epidural block

Skin -> subcutaneous tissue -> subcutaneous fat -> supraspinous ligament -> intraspinous ligament -> ligamentum flavum -> epidural space

List the structures a needle passes through for a subarachnoid block

Skin -> subcutaneous tissue -> subcutaneous fat -> supraspinous ligament -> intraspinous ligament -> ligamentum flavum -> epidural space -> dura mater -> subdural space -> arachnoid mater -> subarachnoid space

Causes of decreased rate of rise

Slower induction -> decreased wash in or faster uptake ↓WASH IN: ↓ FGF ↓ alveolar ventilation ↑FRC ↑time constant ↑anatomic dead space ↑UPTAKE ↑ CO ↑ Solubility ↑ Pa/Pv difference

Brugada syndrome

Sodium ion channelopathy of the heart common in males from SE Asia. Common cause of nocturnal death from VT or VF. may require ICD or pad placement during surgery Diagnostic EKG finding: RBBB & ST elevation in V1-V3

Second Degree Heart Block Type II etiology

Some P's conduct to the ventricles and some don't, usually regular ratio Defect occurs in Bundle of His or BB's Cause: structural conduction deficit or MI Usually symptomatic: syncope, palpitations Tx: pacemaker (atropine usually not effective)

SpO2 to PaO2

SpO2 90% = PaO2 60mmHg SpO2 80% = PaO2 50mmHg SpO2 70% = PaO2 40mmHg Cannot extrapolate when SpO2 is 100%

Superior valeculla

Space between base of tongue and epiglottis -Applying force here pulls the epiglottis away from the glottis opening

Space of Disse

Space between sinusoids and hepatocytes where lymph and proteins drain liver is responsible for 1/2 of lymph production in body

Absolute contraindications for caudal anesthesia

Spina bifida Meningomyelocele of the sacrum Meningitis

Absolute contraindications to caudal anesthesia

Spina bifida Meningomyelocele of the sacrum Meningitis

Subarachnoid Block

Spinal Intrathecal SAB (Spinal Anesthetic Block)

Most common cause of ION

Spinal surgery in the prone position can also occur after radical neck dissection or CPB

VIA pharmacologic effect and target region for analgesia

Spinothalamic tract: Nociceptive pain signal along ascending pain pathways are inhibited here

Aldosterone Antagonists

Spironolactone, Eplerenone MOA: Inhibits K excretion and Na reabsorption in the collecting ducts Blocks aldosterone at the mineralcoricoid receptors

Curare capnography

Spontaneous breaths during mechanical ventilation If present during spontaneous ventilation, indicates inadequate muscle relaxant reversal.

Larynx (C space and number of cartilages)

Starts at C3 to C6 3 single cartilages -3 paired cartilages

Static compliance

Static = Not moving Measures lung compliance when there is no airflow The pressure required to keep lungs inflated is a function of the tendency of the chest wall to collapse - Resistance does not figure in because there is not airflow

Causes of left shift on the PaCO2 response curve

Stimulates Ventilation -Anxiety -Surgical stimulation -Metabolic acidosis -↑ ICP -Salicylates -Aminophylline -Doxapram

Events that cause autonomic hyperreflexia

Stimulation of bladder, bowel, or uterus Bladder catheterization surgery (esp. cystoscopy or colonoscopy) Bowel movement Cutaneous stimulation Childbirth

Organism most likely to cause post-spinal bacterial meningitis?

Streptococcus viridans

Nervous system complications of SLE

Stroke Psychosis/dementia Peripheral neuropathy

Affinity of NMB's for sugammadex

Strong but not irreversible Mechanisms for dissociation is unknown

Cause of new onset seizures in adulthood

Structural brain lesion: tumor, head trauma, CVA Metabolic cause: hypoglycemia, drug toxicity, withdrawal, infx

extrinsic laryngeal muscles that elevate the larynx

Stylohyoid Geniohyoid Mylohyoid Thyrohyoid Digastric Stylopharyngeus

Distance from insertion site to the junction of SVC and right atrium

Subclavian: 10cm Right IJ: 15cm Left IJ: 20cm Femoral: 40cm Right median Basilic: 40cm Left median Basilic: 50cm

Most important site of pain modulation

Substantia gelatinosa in the dorsal horn

What factors increase the risk of contracture in Myotonic Dystrophy

Succ Anticholinesterase reversal Hypothermia (shivering)

NMB's that cause histamine release

Succ Atracurium Mivacurium Patients who are sensitive to a higher heart rate or reduced afterload should not receive

Drugs metabolized by pseudocholine esterases

Succ Mivacurium Ester local anesthetics (one i)

Meds to avoid w/ hypokalemic periodic paralysis

Succ Potasium containing solutions (LR)

Meds that are safe with hypokalemic periodic paralysis

Succ??? NDNMB's Acetazolamide

NMB most likely to cause Anaphylaxis

Succinylcholine, but some source say ROC so they are probably the 2 most likely to cause anaphylaxis.

Order of opioid potency

Sufentanil > Fentanyl=Remi > Alfentanil > Hydromorphone > Morphine > Meperidine

Lipophilic opioid profile

Sufentanil and Fentanyl faster onset less respiratory depression (early only) more systemic absorption (higher plasma cont.)

Arterial pressure waveform

Systolic BP = peak of waveform Diastolic BP = trough of waveform Pulse pressure = Peak - trough Contractility = upstroke Closure of aortic valve = Diacrotic notch Stoke volume = area under the curve

3 determinants of flow through the LV outflow tract

Systolic LV volume Force of LV contraction Transmural pressure

The facet joint is formed by which 2 structures

Superior articular process Inferior articular process

innervates the vocal cords

Superior laryngeal internal branch Recurrent laryngeal

innervates posterior epiglottis

Superior laryngeal internal branch (X)

innervates the laryngeal mucosa to the level of the cords

Superior laryngeal internal branch (X)

Combitube

Supraglottic double lumen device placed blindly in hypopharynx. Occludes esophagus while ventilating larynx (tip is placed in the esophagus). Do not hold cricoid pressure when placing this device. If there is pathology below the glottis this device may not work. Contraindications: •Intact gag reflex •Prolonged use (ischemia) •Esophageal disease (Zenker's diverticulum) •Ingestion of caustic substances

2 types of analgesia that all opioid receptors provide

Supraspinal spinal

5 ligaments of the spine from superficial to deep

Supraspinous Interspinous Ligamentum flavum Posterior Longitudinal Ligament Anterior Longitudinal Ligament

pancreatitis surgical procedures

Surgical drainage of pseudocyst: Usually done after cyst matures (6 weeks) Open or CT-guided external drainage Spontaneous resolution of pseudocysts may be expected in 20% or more of patients who have undergone surgical drainage

Autonomic hyperreflexia (dysreflexia)

Sympathectomy above the level of the injury (bradycardia, hypotension) HTN below the level of the injury - further lowers HR d/t baroreceptor reflex 85% of patients w/ injury above T6 will develop AH

CV effects of neuraxial anesthesia

Sympathectomy causes systemic vasodilation Hypotension and Bradycardia

psoas compartment block/lumbar plexus block complications

Sympathectomy of the ipsilateral extremity Volumes > 20mL can create contralateral spread - leading to bilateral sympathectomy retroperitoneal hematoma (coagulopathy contraindicated) renal capsular injection LAST

order of loss of sensation types with local anesthetics

Sympathetic-> Temp-> pain (sharp)-> motor, proprioception, dull pain

Indications for Pacemaker

Symptomatic SA node dysfunction (sinus bradycardia, intra-atrial block, exit block) Symptomatic AV node dysfunction Long QT Dilated cardiomyopathy Hypertrophic obstructive

myasthenia gravis and pregnancy

Symptoms get worse (30% of pts) and antibodies can cross placenta - baby may need airway support after delivery and weakness may last 2-4 weeks.

Enzyme that metabolizes Succ, Mivacurium, and Ester local anesthetics

Synonyms -Plasma cholinesterase -pseudocholinesterase -Butyrylesterase -Type 2 cholinesterase

Enzyme that metabolizes ACh

Synonyms Acetylcholinesterase True cholinesterase Type 1 cholinesterase Specific cholinesterase Genuine cholinesterase

PA pressure

Systolic same as RV Diastolic pressure increases Diactrotic notch present after passing the valve

Vector of Repolarization

T wave -A positive deflection occurs when the vector of repolarization travels away from the positive electrode -The vector of repolarization produces a negative current -B/c the negative current is traveling the opposite direction of depolarization (double negative) the wave usually points in the same direction as the R wave

Level of cardioaccelerator fibers

T1-T4

thoracic dermatomes

T1: medial forearm T2: medial upper arm T3: 3rd and 4th intercostal space T4: nipple line T5 - T6: to xyphoid process T7 - T9: below xyphoid, upper epigastric, level of shoulder blades T10: belly button T11 - T12: below belly button

Sphlanic nerves

T3-T11

Carina

T4-5 Lower part of trachea, richly innervated -Sensitive to sensory stimulation Corresponds with Angle of Louis

Level and function of sympathetic fibers

T5-L1 • Arterial Dilation • Decreased SVR • Increased Venous Pooling • Decreased Preload

drug induced hepatitis

TB meds- INH, rifampin, pyrazinamide Toxic - alcohol, Acetaminophen Tetracycline, penicillin, Sulfonamide, Volatile anesthetics (halothane) Amiodarone, Methyldopa

Therapeutic window

TD50/ED50 the dosage range of a drug that provides safe effective therapy with minimal adverse effects 'margin of safety'

Most sensitive monitor for myocardial ischemia

TEE

Anesthetic mgmt for DMD

TIVA, no succ

Examples of R->L shunts

TOF Foramen ovale Eisenmenger's syndrome tricuspid atresia Ebstein's anomoly

TOF result that indicates residual muscle neuromuscular blockake

TOF < 0.9

Recommendations for block placement/catheter removal: thrombolytic agents

TPA, streptokinase, alteplase, Urokinase Absolute contraindication to neuraxial anesthesia

Neuraxial recommendations w/ Thrombolytic agents

TPA, streptokinase, alteplase, urokinase Absolute contraindication to neuraxial anesthesia

Hypoglycemia s/s under anesthesia

Tachycardia Diaphoresis Anxiety Tremors Piloerection Pupillary dilation vasoconstriction can cause irreversible brain damage

Early signs of MH

Tachycardia Tachypnea ↑ EtCO2 Masseter spasm Irregular heart rhythm warm soda lime

Sign of seizure under general anesthesia

Tachycardia, HTN, ↑EtCO2 (d/t ↑O2 consumption)

Examples of Cholinesterase Inhibitors

Tacrine Donepezil (Aricept) Rivastigmine (Exelon) Galantamine (Razadyne)

Regional CEA

Techniques: -local infiltration -Superficial cervical plexus block (C2-C4) -Deep cervical plexus block (C2-C4) Awake patient is best monitor Risk of ipsilateral phrenic nerve block (difficulty breathing during procedure)

Absent seizure (petit mal)

Temporary loss of awareness -more common in children

What places does rheumatoid arthritis in the airway

Temporomandibular joint - mouth opening Cricoarytenoid joints - decreased diameter of glottic opening Cervical Spine - Atlanto-occipital subluxation

Myasthenic Crisis vs. Cholinergic Crisis

Tensilon Test: Administer 1-2mg IV edrophonium -if muscle weakness gets worse than its a cholinergic crisis, and the pt should get an anticholinergic -if muscle weakness improves than its myasthenic crisis

Diencephalon

Thalamus: acts as a relay station that directs information to different cortical structures Hypothalamus: primary neurohumoral organ

Addition

The combined effect of two drugs acting via the same mechanism is equal to that expected by simple addition of their individual actions. 1+1 = 2

Synergistic

The combined effect of two drugs is greater than the algebraic sum of their individual effects. Increases efficacy not potency. 1+1 = 3

Dibucaine results for Typical homozygous, Heterozygous, and Atypical homozygous

Typical homozygous (UU): normal - 70-80 Heterozygous (UA): 50-60 (paralysis for 20-30 min) Atypical homozygous (AA): 20-30 (paralysis for 4-8hr)

Hypokalemia affects on EKG

U wave ST depression Flat T wave Long QT interval

coarctation of the aorta clinical findings

UE BP > LE BP Weak femoral pulse, systolic bruit Diagnostics: aortography, echo, CT/MRI

Hypdrophilic vs lipophilic opioid profiles

The more hydrophilic a drug is the more likely it is to stay in the subarachnoid space and ascend toward the brain. The more lipophilic a drug is the more likely it is to diffuse into the systemic circulation

Murphy eye

an opening in the side of an endotracheal tube near the tip that aids to prevent obstructions of the tube Additional distal opening in the side of the ETT Ventilation port if the distal end is obstructed Decreased trauma during nasal intubation

Kappa receptors

analgesia, low abuse potential dysphoria, sedation, hallucinations, delirium, miosis Diuresis Antishivering Agonist: Dynorphins, Meperidine Antagonist: Naloxone, naltrexone, nalmefene

Bioavailability

The percentage of a drug contained in a drug product that enters the systemic circulation in an unchanged form after administration of the product. How much of the drug enters the bloodstream. So IV drugs are 100%. Intrathecal drugs have very low bioavailability b/c they don't enter the bloodstream.

FA is a function of

The rate of delivery to the alveoli The rate of removal from the alveoli

Why do you not place a patient in trendelenberg after a spinal to fix hypotension

The solution with spread up the thoracic vertebrae causing a high spinal

Why do NMB's cause anaphylaxis

The structure contains antigenic groups that interact with Ig-E which causes mast cell and basophil degranulation. -reflected by an elevated tryptase level

Context sensitive half time

The time for the plasma concentration of a drug to decrease by 50% from an infusion that maintains a constant concentration. The context is the duration of the infusion. A drug with a long context sensitive half time stays in the central compartment longer - fentanyl

CYP 1A2

Theophylline -inducers: tobacco, cannabis, alcohol -inhibitors: erythromycin, ciprofloxacin

Contraindications to using Succ

These are because of the presence of extrajunctional receptors - ie these conditions cause denervation: -upper or lower motor neuron injury -spinal cord injury -Burns -Skeletal muscle trauma -CVA -Prolonged chemical denervation (Mg, long-term NMB infusion, clostridial toxin) -Severe Sepsis -Tetanus -MD (any type of muscular atrophy)

Most common cause of ischemic stroke

cardio-embolitic event = afib

Volatile anesthetics receptors in the spinal cord

These cause immobility: Glycine receptor stimulation NMDA receptor inhibition Na+ channels (Immobility is not d/t GABA binding)

Why do hydrophilic drugs cause late respiratory depression?

They ascend rostrally where they can inhibit the respiratory center late phase is 6-12h

How do local anesthetics cause their effect in epidural anesthesia

They need to diffuse through the dura cuff before they can block the nerve roots -can also leak through intervertebral foramen to enter the paravertebral area

Physiologic factors that effect MAC

Things that increase central neurotransmitter concentration, neurotransmission, and cerebral metabolism increase MAC Things that decreases these things decrease MAC

Optic nerve circulation

carotid artery -> ophthalmic artery -> central retinal artery central retinal artery occlusion can lead to blindness

indication for CEA

carotid stenosis exceeds 70%

P450

carries out most Phase 1 biotransformations located in the Smooth ER of hepatocytes

Problem with placing an epidural catheter too deep

catheter may enter an epidural vein or may project out into the paravertebral space.

TNS - transient Neurological Symptoms treatment

• NSAIDS typical treatment • Opioids or trigger point injections • Almost always spontaneously resolves

Double lumen ETT indications

Thoracic procedures Control of contamination or hemorrhage Unilateral pathology -bronchopleural or bronchocutaneous fistula -large cyst/bullae -lungs have different compliance (single lung txp or unilateral injury)

T2-T6

Thoracic surgery

Larynx membranes

Thyrohyoid Cricothryoid Cricotracheal

Burst suppression

The EEG pattern shows bursts of abnormal activity followed by seconds of flat EEG with no activity. General anesthesia, hypothermia, CPB, cerebral ischemia

cerebral autoregulation

The ability of the brain to maintain constant cerebral blood flow despite changes in systemic arterial pressure over a range of 50 to 150 mm Hg

cerebral autoregulation

The ability of the brain to maintain constant cerebral blood flow despite changes in systemic arterial pressure over a range of 50 to 150 mm Hg Benefit: Ensures that the brain has a steady supply of oxygen and substrates in the face of blood pressure fluctuations.

Antagonism

The action of one drug opposes the action of another. Narcan reversing narcotic 1 + 1 = 0

Opioid Respiratory Depression

The amount of analgesia you get from an opiate is equal to the amount of respiratory depression. analgesia=respiratory depression=addiction liability

MH differential diagnosis

Thyroid storm Neuroleptic malignant syndrome Pheochromocytoma Sepsis Serotonergic syndrome Heat stroke Metastatic Carcinoid Cocaine intoxication

Popliteal block

Tibial is the bigger nerve Landmarks: 1cm proximal to the knee crease, triangle formed by the biceps femoris and semitendinosus mucsle

Inadequate face mask ventilation

Usually due to decreased compliance and increased resistance. Place an oral or nasal airway, >positive pressure for adequate ventilation If ventilation is not optimize, apply two-handed face mask If difficult or impossible face mask ventilation continues, ETT or LMA

Major cause of apnea with neuraxial anesthesia (and what is usually not the cause)

Usually the result of cerebral hypoperfusion, not phrenic nerve paralysis

vomiting center

The area of the brain that is involved in stimulating the physiologic events that lead to nausea and vomiting. Slow reflex, more involved w/ long term nausea Stimulated by: CTZ, GI distention, Pharynx, Higher centers, Mediastinum Inhibited by: High dose opioids

receptor adaptation

The biochemical phenomenon, occurring after continual exposure to a drug. down-regulation=in response to overstimulation (in response to agonist) up-regulation=receptor understimulated (in response to antagonist)

Tests for recovery from NMBs

Tidal vol >5ml/kg: 80% occupied 4/4 twitches, no fade: 70% occupied Vital capacity > 20mL/kg: 70% occupied Sustained tetany (50Hz): 60% occupied double burst stimulation: 60% occupied Inspiratory force -40cm H20: 50% occupied Head lift > 5 sec: 50% occupied Hand grip > 5 sec: 50% occupied Holding tongue blade against force: 50% occupied tongue blade is probably best

Energy pathway for bipolar electrocautery

Tip contains active electrode as well as return electrode - there is no return pad

Purpose of a unidirectional valve

To ensure the gas flows in one direction

Mallampati 2 = ____ hidden

Tonsillary pillars are hidden by tongue

What will happen if Succ is given after Neostigmine or pyridostigmine

The effect of Succ will be prolonged because pseudocholinesterase will be inhibited

Oligodendrocytes

Type of glial cell in the CNS that wrap axons in a myelin sheath. Schwan cells form the myelin sheath in the PNS

Potentiation

The enhancement of the action of one drug by a second drug that has no detectable action of its own. Penicillin + antidiuretic drug = better anti-infective result b/c penicillin stays in system longer. Usually used to mean synergism 1 + 0 = 3

Ventilation effect

The faster you breath, the faster you go to sleep

Concentration effect

The higher the concentration of anesthetic delivered, the faster its onset of action -this is also referred to as overpressuring -Only clinically relevant w/ N2O 2 components of the concentration effect: 1. the concentrating effect 2. Augmented Gas inflow

psoas compartment

The lumbar plexus is contained within a sheath within the psoas compartment

CREST syndrome

Type of scleroderma Calcinosis, Raynaud's, esophageal dysmotility, Sclerodactyly, Telangiectasia

distribution of body water of a 70kg patient

Total body water: 42L Intracellular: 28L, Extracellular: 14L Plasma Vol: 4L, Interstitial fluid: 10L

If ↑PIP & ↑PP

Total compliance has decreased or Tidal Volume has increased

Lower airway components (5 parts)

Trachea Bronchi Bronchioles Respiratory bronchioles Alveoli

Risks of wake up test

Tracheal extubation Removal of IV & art line access Air embolism Awareness Pain Damage to surgical instrumentation

Factors that decrease CVP

Transducer above the phlebostatic axis Hypovolemia

Factors that increase CPV

Transducer below the phlebostatic axis Hypervolemia RV failure Tricuspid stenosis or regurgitation Pulmonic stenosis Pulmonary hypertension PEEP VSD Constrictive pericarditis Cardiac tamponade

Affect of transducer placement on CVP measurement

Transducer placed above 0 point underestimates CVP Transducer placed below 0 point overestimates CVP

Amaurosis fugax

Transient visual loss in one eye - sign of impending stroke -emboli travel from internal carotid to opthalmic artery -> retinal ischemia

TIPS procedure

Transjugular intrahepatic portal-systemic shunt, lowers portal pressure in portal HTN Bypasses portion of the hepatic circulation by shunting blood from the portal vein to the hepatic vein reduces back pressure on sphlanic organs and ↓ bleeding from varices & ↓ascites sig risk: hemhorrage Cather placed in R IJ and advanced via Inferior Vena Cava into the right hepatic vein Can have lg amounts of bld loss Avoid N2O

A-delta fibers

Transmit fast pain that is sharp and well localized

C fibers

Transmit slow pain that is dull and poorly localized - small nerve fibers, poorly myelinated or unmyelinated

dorsal column-medial lemniscal pathway

Transmits fine touch, proprioception, vibration, and pressure 2-point discrimination = high degree of localizing the stimulus large, myelinated, rapidly conducting fibers transmits sensory information faster than anterolateral system

Anterolateral system - Spinothalamic tract

Transmits pain, temperature, crude touch, tickle, itch, and sexual sensation Smaller, myelinated, slower conducting fibers Transmits sensory information 1/3-2/3 times slower than dorsal column No 2 point discrimination

Unacceptable response to nerve stimulator (interscalene)

Trapezius Diaphragm (hiccup)

Cerebral oximetry function

Travels in a elliptical pathway from the emitting diode Arterial and venous hgb absorb different frequencies of infrared light Cerebral blood is 1 part arterial, 3 parts venous (75% venous) ↓oxygen delivery -> ↑cerebral oxygen extraction -> ↓venous hgb saturation

Postassium Sparing Diuretics

Triamterene, amiloride MOA: Inhibits K excretion and Na reabsorption in the collecting ducts Independent of aldosterone

Innervates the anterior tongue

Trigeminal (V) - mandibular branch

Trismus vs Masseter muscle rigidity

Trismus = jaw is tight but can still be opened (normal reaction succ) Masseter = jaw cannot be opened (not corrected by NMB, b/c its an increase in intracellular Ca+) If pt has masseter spasm, assume MH

Light absorbed throughout the pulse cycle

Trough of the pulse waveform = greater amount of venous blood in the tissue sample Peak of the pulse waveform = greater amount of arterial blood in the tissue sample Pulse oximeter calculates the absorption ratio on a continuous basis to determine SpO2

Vocal folds (name, anatomy)

True vocal cords -Attach anteriorly to the thyroid cartilage and posteriorly to the arytenoids

Which epidural needle reduces the risk for PDPH the most and why

Tuohy 30 degree curvature and blunt tip

Magnet with an ICD

Turns ICD off

Magnet with a pacemaker/ICD

Turns off ICD - no effect on pacemaker -pacemaker function still subject to EMI

List the branches of CN VII and function

Two zebras bit my cat Temporal Zygomatic Buccal Mandibular Cervical Both motor and sensory Facial movement, eyelid closing, taste for anterior 2/3 of tongue

Pancreatic txp

Tx for patients w/ insulin-dependent DM refractory to medical management Frequent comorbidities: Ischemic cardiac dx, Renal insufficiency, PVD, ketoacidosis, chronic hypertension, chronic hyperglycemia, gastroparesis, and retinopathy Most pt's will need dialysis postoperatively DM-> joint stiffness-> difficult airway (prayer sign) Do not give fluids rapidly= may result in allograft edema-> graft failure

Most difficult aneurysms to repair

Type 2 & 3

Aneurysm repair w/ most significant surgerical risk including paraplegia

Type 2 - d/t mandatory stopping of blood flow to renal and some of radicular arteries (Artery of Adamkiewicz) - supplies anterior spinal cord

What causes postop myalgia

Uncoordinated muscle contractions b/f paralysis (fasciculations)

VIA effects on neurophysilogy

Uncoupling ↓CMRO2, ↑CBF autoregulation CSF dynamics N2O: ↑CMRO2, ↑CBF

Most important information to have about a patient with PPM before surgery

Underlying rhythm If failure occurs: Isoproterenol, Epi, and/or atropine

Wernicke's area

Understanding speech

Abx prophylaxis is not required for?

Unrepaired cardiac valve disease CABG coronary stent placement GI endoscopic procedures w/out infx GU procedures w/out infx

Transtracheal Jet Ventilation Contraindications

Upper airway obstruction Laryngeal injury Inspiration requires ~50psi. Expiration is passive

ALS S/S

Upper neuron: spasticity, hyperreflexia, loss of coordination Lower neuron: muscle weakness, fasciculations, and atrophy Often begins in hands: spreads to tongue, pharynx, larynx, and chest does not affect ocular muscles Orthostatic hypotension, resting tachycardia sensation is intact respiratory failure is most common cause of death

Second gas effect

Use a very low solubility agent along with another agent of higher solubility causes faster uptake of the slower drug -the use of N2O during induction will hasten the onset of a second gas -This is because of the concentration effect that N2O has on FA/FI -The rapid uptake of N2O causes the alveoli to shrink which increases the alveolar concentration of the second gas relative to alveolar volume -the relative partial pressure of O2 in the alveoli also increases

Phillips blade

Used for peds age 2-6 Provides great visibility directly to the trachea -Strait Jackson blade design with curved distal tip Child: 1 Adult: 2

Oral RAE ETT

Used in ENT surgery to provide full access to the face, taped to lower lip

Nasal RAE ETT

Used in oral surgery

CTP score

Used to assess the severity of cirrhosis(and subsequent anesthetic risk) A (mild) = 5-6 points B (moderate) = 7-9 points C (most severe) = 10-15 points

Types of Evoked Potentials

Used to montior the integrity of a neural pathway Somatosensory: SSEP (monitors dorsal column - medial lemniscus) Motor: MEP (monitors corticospinal tract) Visual: VEP Brainstem Auditory: (BAEP)

Indication for TIPS

Used to treat portal hypertension usually caused by cirrhosis or as a temporary solution for hepatorenal syndrome

Reinforced ETT

Used when a standard tube would be likely to kink

Bronchial Blocker

Used with a single lumen ETT to ventilate a single lung.

U wave

Usually absent: gravestone sign Hypokalemia

Summarize nerve injury outcomes for Vagus, Internal branch of superior laryngeal, External branch of superior laryngeal, and Recurrent laryngeal (Unilateral and Bilateral)

Vagus Unilateral: Hoarseness, Bilateral: Aphonia Internal branch of superior laryngeal No effect - this nerve is sensory only External branch of superior laryngeal Unilateral: Minimal effects Bilateral: Hoarseness and voice fatigue Recurrent laryngeal Unilateral: Hoarseness - left is most common Bilateral: Stridor, dyspnea (acute injury). aphonia (chronic injury)

Physiochemical properties of Sevo

Vapor pressure: 157mmHg Boiling point: 59 Molecular wt: 200 g/mol Preservative: No Stable in hydrated CO2 absorber: No Stable in dehydrated CO2 absorber: No Toxic byproduct: Compound A

Physiochemical properties of Iso

Vapor pressure: 238mmHg Boiling point: 49 Molecular wt: 184 g/mol Preservative: No Stable in hydrated CO2 absorber: Yes Stable in dehydrated CO2 absorber: No Toxic byproduct: Carbon Monoxide

Physiochemical properties of N2O

Vapor pressure: 38,770mmHg Boiling point: -88 Molecular wt: 44 g/mol Preservative: No Stable in hydrated CO2 absorber: Yes Stable in dehydrated CO2 absorber: Yes Toxic byproduct: None`

Physiochemical properties of Des

Vapor pressure: 669mmHg Boiling point: 22 Molecular wt: 168 g/mol Preservative: No Stable in hydrated CO2 absorber: Yes Stable in dehydrated CO2 absorber: No Toxic byproduct: Carbon Monoxide

3 major complications of cirrhosis

Variceal hemorrhage from portal hypertension Intractable fluid retention (ascites & hepatorenal syndrome) Hepatic encephalopathy or coma

3 major complications from cirhossis

Variceal hemorrhage from portal hypertension Intractable fluid retention in the form of ascites and the hepatorenal syndrome Hepatic encephalopathy or coma

Causes of decreased perfusion

Vasoconstriction Hypothermia Hypoperfusion Raynaud's Syndrome

Type of vessels most affected by spinal induced vasodialtion

Venous capacitance vessels -> decreased preload -> decreased CO -> decreased BP

Causes of decreased EtCO2 - equipment malfunction

Ventilator disconnect Esophageal intubation Poor seal w/ LMA or ETT Sample line leak Airway obstruction Apnea

What is volatile anesthetics site of action for producing immobility

Ventral horn of the spinal cord

VIA pharmacologic effect and target region for immobility

Ventral horn: upper and lower neurons synapse here

Where do motor and autonomic neurons exit the spinal cord?

Ventral root

Diastolic compliance curve

Ventricular filling pressure that results from a given end-diastolic volume -Decreased compliance shifts curve up and left -Increased compliance shifts curve down and right

In what order do Ca channel blocker impair contractility

Verapamil > nifedipine > diltiazem > nicardipine

Classes of CCB's

Verapamil: Phenylalkamine Diltiazem: Benzothiazepine Nicardipine: Dihydropyridine

Vertebrae

Vertebral Body • 2 Pedicles • 2 Transverse Processes • 2 Laminae • 1 Spinous Process • 4 Articular Processes -2 Superior -2 Inferior -Facet or Zygapophyseal joints -When stacked make the intervertebral foramina

Lateral border of the epidural space

Vertebral pedicles

4 tissue types, % body mass and % CO

Vessel rich: body mass 10%, CO: 75% Muscle & Skin: body mass: 50%, CO: 20% Fat: body mass: 20%, CO: 10% Vessel poor: body mass: 20%, CO: <1%

Anesthesia MOA

We don't know. We know how they work but not why

Sinus Arrhythmia

When SA node's pacing rate varies with respiration usually benign Brainbridge reflex = ↑venous return, ↑HR inhalation -> ↓intrathoracic pressure -> ↑venous return -> ↑HR Exhalation -> ↑intrathoracic pressure -> ↓venous return -> ↓HR

Diagnosis for AO subluxation

When the distance between the anterior arch of the atlas and the otonoid process is > 3mm

Inverse Steal (Robin Hood, Reverse Steal):

When the patient with an ischemic region of brain is hyperventilated such that PaCO2 falls, blood vessels in non-ischemic brain constrict and blood is diverted to ischemic brain which vessels are already maximally dilated. This theory does not seem to work clinically

When is retrograde intubation most useful

When ventilation is possible. Not as useful in a cannot intubate, cannot ventilate scenario. takes 5-7 minutes often done in a controlled setting of a known or suspected difficult airway. Not as helpful as a rescue measure

Cirrhosis etiology

alcoholism (fatty infiltration) biliary obstruction (inflammation) chronic hepatitis (inflammation) right-sided heart failure (↑ hepatic vascular resistance) α₁-antitrypsin deficiency (genetic) Wilson's disease (genetic) hemochromatosis (iron overload)

Unitary Theory

all anesthetics share a similar mechanism of action, but each may work at a different site

When does the oscillatory (NIBP) BP measurement not work

With non-pulsatile flow (LVAD, CPB)

QTc interval

Women < 0.47 sec Men < 0.45 sec Long QT syndrome

Duchenne muscular dystrophy

X-linked recessive disease that results from the absence of the dystrophin protein. Dystrophin is a critical element of skeletal and cardiac muscle cell cytoskeleton. The absence of dystrophin alters the type and number of postjunctional nicotinic receptors, making them more permeable to potassium.

Duschenne Muscular Dystrophy

X-linked recessive disease where cells do not make dystrophin. The lack of dystrophin destabilizes the sarcolemma during muscle contraction and increases membrane permeability. Extracelluar Ca+ enters cells (↑metabolism) Intracellular K+ (cardiac arrest) & myoglobin (renal failure) leave the cell Normal RyR1 receptor

Is the OR equipment grounded

Yes

Is Succ safe to use in renal failure patients

Yes if the potassium level is normal

Why do you need a PA to measure SVO2

You need a sample with blood mixed from the SVC, IVC, and coronary sinus

An electric current that enters the body will leave ____

along the path of least resistance

plasma concentration curve

alpha = distribution from the plasma to the tissues beta = elimination from the plasma by the clearing organs

Factors that cause higher risk of PDPH

Younger age Female Pregnant Cutting tip needle larger diameter needle using air for LOR syringe Needle perpendicular to long axis of meninges

chirality

a molecule with one chiral carbon will exist as 2 enantiomers -a carbon bound to 4 DIFFERENT atoms

adenosine

a nucleoside slows conduction through the AV node stimulates the cardiac adenosine-1 receptor -> K+ exits the cell (more negative) -rapid metabolism -SVT and WPW -not for afib, flutter, VT -Can cause bronchospasm w/ asthma PIV dosing: 6mg -> 12mg Central dosing: 3mg -> 6mg

Glasgow Coma Scale (GCS)

a scoring system used to describe the level of consciousness in a person following a traumatic brain injury

mass spectrometry

a technique that separates particles according to their mass bombards a gas sample with electrons creating ion fragments

CVP waveform and electrical events

a wave= right atrial contraction (diastole) c wave= ventricular contraction, buldging of TV into RA x descent= RA relaxation v wave= Passive filling of RA y descent= RA empties through open TV (venticular filling)

Phenanthrene alkaloids

a. Natural: morphine, codeine, thebaine b: Semisynthetic: Diacetylmorphine (heroin), Hydrocodone, Hydromorphone, Oxycodone, Oxymorphone Semisyth antagonist: Naloxone, naltrexone, nalmefene c. Synthetic: Morphinian derivatives, Benzmorphans

Piperidine Derivatives (Phenylpiperdines)

a. Phenylpiperdines: Mereperidine, Loperamide b. Anilidopiperidines (no histamine release): Fentanyl, Sufentanil, Alfentanil, Remifentanil

What causes the loss of the a wave

afib (no atrial contraction) V pacing if no underlying rhythm

The pressure required to inflate the lungs is a function of what 2 factors?

airway resistance lung/thoracic compliance

Cause and consequence of chest wall rigidity

a/e of high dose narcotic injected quickly (tight chest). It is actually not the chest wall that causes difficulty ventilating, it is laryngeal muscle contraction (caused by mu receptor stimulation in the CNS) Use of N20, elderly, and absence of NMB increase the risk. Only occurs after pt has lost consciousness (ie, so ok to paralyze). Can impair spontaneous ventilation and make controlled ventilation difficult/impossible. Treatment: Succ or naloxone

Correct location for CVP catheter tip?

above the junction of the superior vena cava and right atrium

pericardial effusion

accumulation of fluid in the pericardial sac -not associated with increased pericardial pressure or impaired diastolic filling

Drugs to avoid w/ liver dx

acetaminophen, halothane, amiodarone, tetracycline, sulfonamides, penicillin

Partial agonist

activates a receptor but cannot produce a maximum response (partial cellular response). may also be able to partially block the effects of full agonists by competing for binding sites. -lower efficacy than a full agonist.

Why do neuraxial opioids cause N/V?

activation of opioid receptors in the area postrema of the medulla and in the vestibular apparatus

MOA for opioid induced N/V

activation of opioid receptors in: -area postrema of the medulla -vestibular apparatus

cardiac tamponade

acute compression of the heart caused by fluid accumulation in the pericardial cavity - does impair diastolic filling - interferes with the hearts ability to act like a pump

Familial Periodic Paralysis

acute episodes of acute skeletal muscle weakness, accompanied by changes in serum potassium concentration -dx is in the muscle tissue not the NMJ Hypokalemic = Ca+ ch problems Hyperkalemic periodic paralysis = Na+ ch problems

Sarcomere arrangement for eccentric hypertrophy

additional sarcomeres are added in a series

Sarcomere arrangement for concentric hypertrophy

additional sarcomeres are added in parallel

Phase 2 metabolism: conjugation

adds a polar/water soluble substrate to molecule -renders drug inactive, hydrophillic and ready for elimination

Conus meddularis location

adult: L1-L2 Infant: L3

Airway complication of RA

atlantoaxial subluxation and separation of the atlanto-odontoid articulation Cause: weakening of the transverse axial ligament -> allows the odontoid to directly compress the spinal cord at the level of the foramen magnum -> risk for quadriparesis & paralysis

AV synchrony

atria and ventricles depolarizations are coordinated to allow atrial contractions to augment the filling of the ventricles This is made possible by a thin layer of connective tissue that electrically separates the atria and ventricles. This ensures that the AV node is the only electrical pathway between the chambers (unless there is a pathologic accessory pathway)

Temporal lobe

auditory cortex and language

Guillain-Barre pathophysiology

autoimmune attack on peripheral myelin - loss of AP conduction lasts 2-4 weeks

rheumatoid arthritis (RA)

autoimmune d/o of the synovial joints

systemic lupus erythematosus (SLE)

autoimmune disease characterized proliferation antinuclear antibodies Mostly women Does not involve the spine Butterfly rash

myasthenia gravis

autoimmune neuromuscular disorder characterized by weakness of voluntary muscles -they have too few postsynaptic nicotinic ACh receptors at the neuromuscular junction. Therefore the muscles are under stimulated. -Sensitive to NDNMB's (will cause stronger response) -Resistant to Such -Anticholinesterase agents are a first line therapy for myasthenia gravis -STONGLY associated w/ thymoma

Beta waves

awake and alert or "light anesthesia" 13-30cycles/sec high frequency, low voltage

Nerve associated w/ deltoid twitch response

axillary

Epidural space

space between the dura mater and the wall of the vertebral canal Runs the entire length of the spine Contains • Blood Vessels • Fat • Lymphatics • Nerve Roots • On Average Lumbar anterior/posterior (AP) distance = 5 mm

sacral dermatomes

back of legs and genitals S1: Lateral and soul of foot S2: back of thigh S3-S5: perineal area

Rebreathing capnography

baseline does not return to 0 Exhausted CO2 absorbent, incompetent expiratory valve, hole in the inner tube of a bain circuit, inadequate FGF in Mapleson circuit, rebreathing under the drapes of a patient whose not intubated

Elevated EtCO2 with normal plateau

baseline returns to 0 Occurs with ↑CO2 production or ↓alveolar dead space Examples ↑CO2 production: MH, sepsis, fever, hyperthyroidism Examples ↓alveolar dead space: hypoventilation, narcotics

Why should CVP be measure at end expiration

because extravascular pressure equals atmospheric pressure

PDPH treatment

bed rest Hydration NSAIDs caffeine Epidural blood patch Sphenopalantine ganglion block

Recommendations for block placement/catheter removal: warfarin

before block: Hold 5d Can remove catheter when INR < 1.5

Upper motor neuron (corticospinal tract)

begin in the cerebral cortex and end in the ventral horn -cell body originates in the cortex

dura mater borders

begins at foramen magnum and ends at the dural sac

paravertebral

beside the vertebrae

First nerve fiber type to be blocked

beta even though c fibers are smaller beta are blocked first because C fibers have no myelin and therefore the whole fiber must be blocked.

Factors that cause LVOT obstruction to get worse

beta agonists Ketamine Pancuronium Desflurane oxytocin Light anesthesia Histamine releasing drugs: morphine, demerol, thiopental, atracurium Vasodilators neuraxial anesthesia Hypovolemia (blood loss) Postural changes (Reverse T-burg) PPV Valsalva Digoxin

Class II antiarrhythmic drugs

beta blockers Slow phase 4 depolarization in the SA node ex. esmolol, propranalol, Metoprolol, Atenolol

Full agonist

binds to a receptor and turns on a cellular response, mimics endogenous ligand -produces a maximal response -continuous administration may cause down regulation of receptors ex. dopamine, norepi, propofol, dopamine

inverse agonist

binds to receptor and causes the opposite effect as the agonist -negative efficacy -ex. propranolol bind to beta 1 and causes a decrease in cAMP (it doesn't just prevent the agonist from binding)

Antagonist

binds to receptors to prevent agonist binding therefore preventing cellular response -does not have efficacy -continuous administration may cause up-regulation of receptors (ex. beta blockers)

How does succinylcholine work?

binds to the nicotinic receptors on the motor endplate causing them to depolarize but because it is not hydrolyzed by acetylcholine esterase, the muscle stays contracted causing a paralysis.

Glucagon

biologic antagonist to insulin enhance hepatic glucose output and increase plasma glucose stimulates catabolic processes (fat metabolism, gluconeogenesis) Hyperglycemia ↓ glucagon release from αcells.

Pharmacobiophasics

biophase = effect site -drug concentration in the biophase (not the plasma) determines its clinical effect -plasma concentration and effect site concentration

Causes of Neuraxial bradycardia

blockade of T1-T4 -> relative increase of pSNS tone Unloading ventricular mechanoreceptors->Bezold-Jarisch reflex Unloading of the stretch receptors in the SA node

Nerve block for the oropharynx - nerve and location

blocks glossopharyngeal 1-2mL LA at the tonsillar pillars bilaterally

Nerve block for the larynx above the cords - nerve and location

blocks superior laryngeal branch 3mL LA at the inferior aspect of the greater cornu and hyoid bone bilaterally

CPB key points

blood flow is non-pulsatile - use MAP Full bypass = when all venous return is drained into the reservoir partial bypass = heart receives and pumps some blood on its own LV vent: drains the blood from the Thebesian and bronchial circulation - goal is to prevent subendocardial compression and resulting ischemia CPB creates a systemic inflammation that can cause organ failure

Clearance is directly proportional to

blood flow to clearing organ Extraction ratio Drug dose

Sacral cornu

bony nodules that flanks the sacral hiatus

Sevo and soda lime

can be unstable in both hydrated and dessicated soda lime -> forms compound A -basis for minimum fresh gas flow

hyperbaric trendelenberg

can cause high spinal before block is set Usually levels off at T4 w/ supine position. Can increase to T1 if put in Trendelenberg

Des and Iso and soda lime

can form carbon monoxide Des > Iso

First order neuron (Dorsal)

detects a stimulus and transmits a signal to the spinal cord -enters through the dorsal root ganglion -ends in the medulla -Ascends on ipsilateral side (same side it enters on) -Synapses w/ 2nd order neuron in the medulla

Mainstream (In-line) CO2 analysis

device attached to ETT faster response time, doesn't require water trap or pumping mechanism

Identify baricity based on the dilutional agent

dextrose -> hyperbaric saline -> isobaric water -> hypobaric. (10% procaine in water is the exception b/c of the high concentration, it is hyperbaric)

Use of N2O with retinal bubble

d/c N2O 15 min b/f bubble is placed avoid N2O for 7-10 days after SF6 bubble is placed Air bubble: 5 days Perfluoropropane bubble: 30 days Silicone oil bubble: No contraindication

Eaton-Lambert Syndrome

d/o of the NMJ Antibodies block presynaptic calcium channels which blocks the release of Ach from the presynaptic neuron - IgG mediated destruction post-synaptic Ach receptors are normal

Complete spinal cord injury

damages upper motor neuron -> leads to flaccid paralysis, loss of sensation below the level of the injury, & bowel & bladder dysfxn After acute phase, spinal reflexes return and may lead to spasticity

Volatile anesthetics

decrease hepatic blood flow (b/c of a decrease in MAP) - Iso does this the least

VIA effect on evoked potentials

decreased amplitude and increased latency N2O makes this worse

how does higher altitude effect delivery of Des

decreased delivered partial pressure d/t decreased atmospheric pressure - ie an underdose This doesn't actually happen b/c of the vaporizer. partial pressure = %vol x atmospheric pressure (decreased atmospheric pressure decreases the partial pressure)

What causes thrombocytopenia in liver dx

decreased platelet production and splenic consumption

Incompetent Inspiratory valve

decreased slope during inspiratory phase part of the exhaled breath re-enters the inspiratory limb, so the patient rebreathes some of the previously exhaled CO2 on the next breath

How hypothermia affects blood gases

decreased temp increases the amount of CO2 dissolved in plasma. Alpha stat: does not correct for temp - use in adults pH stat: corrects for temp - use in peds

20-40 min of bier block

deflate and reinflate

Underlying cause for torsades de pointes

delay in ventricular repolarization (phase 3 of AP)

Procedures that are high risk for infective endocarditis

dental procedures gingival manipulation or damage to the mucosa Respiratory procedures that perforate the mucosal lining w/ incision or biopsy Biopsy of infective lesions on the skin or muscle

What region of the lung is zone 3 in?

dependent Sitting: base of lung Supine: toward the back Prone: toward the chest Lateral: dependent lung

Opioid Respiratory Depression MOA

depress respiratory center's sensitivity to CO2 (drives ventilation) -shifts CO2 curve to the right. Narcotics increase partial pressure of CO2 in alveoli which decreases RR and VT. Opioids are also antitussives which is helpful in anesthesia.

Ulnar nerve block

derived from medial cord of the brachial plexus elbow flexed 90 degrees, injected b/w the olecranon and medial epicondyle

Median nerve block

derived from the lateral and medial cords of the brachial plexus In the antecubital fossa, inject medial to the brachial artery *do not use this block in a patient w/ carpal tunnel syndrome

Radial nerve block

derived from the posterior cord of the brachial plexus inject between the biceps tendon and brachioradialis

Baricity

describes a local anesthetic solution relative to CSF

Cobb angle

describes the magnitude of spinal curvature in scoliosis -2 most displaced vertebrae at the top and bottom are compared

Scleroderma

excessive fibrosis in skin and organs

Cerebral Salt Wasting (CSW)

excessive renal wasting of sodium and chloride after brain surgery Brain releases natriuretic peptide and this results in hyponatremia caused by salt wasting in the kidneys

Cauda Equina Syndrome cause

exposure to high concentrations of LA

filum terminale

extends from conus medullaris to the coccyx -continuation of the pia mater caudal to the conus medullaris, anchors spinal cord to coccyx

Pharynx

extends from the base of the skull to the level of cricoid cartilage

Pia mater

external covering of the spinal cord, should not be punctured during spinal ansthesia

Epidural hematoma presentation

extremity weakness numbness low back pain bowel and bladder dysfunction

Phase 3 metabolism: elimination

facilitates the REMOVAL of metabolites from cells to the urine or bile -ATP dependent carrier proteins that transport drugs across cell membranes

Two compartment model

fat mass and fat free mass A is redistribution B is elimination

Insulin

favors fat storage. Inhibits the use of fat as an energy source by inhibition of glucagon release

Risk factors for PDNV

female, age <50y, Hx of PONV, PONV in PACU

Risk factors for PONV

female, age <50y, Hx of PONV, high doses of opioids, surgery duration >1h, Laparoscopic procedures *Hx of PONV is most important, will probably happen again, have a plan

ventral corticospinal tract

fibers that innervate the axial muscles then descend via the ventral corticospinal tract on the ipsilateral side. fibers crossover to the contralateral side of the spinal cord in the cervical or thoracic region

lateral corticospinal tract

fibers that innervate the limbs crossover to the contralateral side in the medulla, then descend through the lateral corticospinal tract

basal ganglia

fine control of movement

Acceptable response to twitch monitor (infraclavicular)

finger twitch

When is risk of stent re-stenosis greatest?

first 30 days

three-neuron afferent pain pathway

first order: periphery to dorsal horn second order: dorsal horn to thalamus third order: thalamus to cerebral cortex

injury below the level of decussation in the medulla

flaccid paralysis on the ipsilateral side of the body

Guillain-Barre clinical presentation & Cause

flu-like symptoms precede paralysis Cause: Camplyobacter jejuni bacteria, Epstein Barr virus, Cytomegalovirus. Other causes: vaccinations, surgery, lymphomatous disease

TIA

focal neurologic deficit that spontaneously resolves w/in 24h

Metabolites of N2O

for all intents and purposes N2O is not metabolized by the body

How long should Succ be avoided after a denervation injury

for first 24-48h, and for up to 1 year after (except for burn which Succ should be avoided for several years following)

Cranial border of the epidural space

foramen magnum

Sural nerve

formed from the branches of the tibial and common peroneal nerve sits behind the lateral malleolus sensation to the heel and sole of the foot Needle is inserted midline b/w the Achilles tendon and the lateral malleolus

Anterolateral peripheral receptors

free nerve endings nociceptors

Start and end points of the epidural space

from foramen magnum to sacrococcygeal ligament

Coronary steal phenomenon

global dilation of the coronary arteries (by VIA) such that stenotic vessels which are already maximally dilated lose some of their blood flow as it is directed to dilated vessels that are feeding healthy cardiac tissue. The heart has an O2 extraction ratio of 75% so it cannot increase the amount of O2 it is extracting. The only way to get more O2 to the tissues is to increase flow. Coronary steal is the inhibition of this compensatory mechanism

sensory cells of the hypoxic drive

glomus type 1 cells in the carotid bodies -hypothesized that VIA create reactive oxygen species that impair glomus type 1 cells

Common substrates for conjugation

glucuronic acid glycine acetic acid sulfuric acid methyl group (CH3)

For FA/FI to increase there must be

greater wash in or reduced uptake

laminae

grey matter is subdivided into 9 laminae Laminae I-VI: dorsal grey matter, sensory Laminae VII-IX: ventral grey matter, motor

Familial periodic paralysis

group of diseases characterized by intermittent attacks of skeletal muscle weakness associated w/ hypo or hyper-kalemia

Myotonic Dystrophy

group of diseases where the hallmark is prolonged muscle contracture (myotonia) after a voluntary skeletal muscle movement

Spinal tracts

group of fibers inside the white matter that relay information up and down the spinal cord

pheochromocytoma clinical findings

h/a palpitations diaphoresis

cirrhosis

healthy hepatic tissue is replaced by fibrous tissue and nodules

Conduction heat loss

heat loss due to contact with another surface

evaporation

heat loss through evaporating water

Isoflurane chemical characteristics

heavy Cl atom increases potency twice as potent as Sevo, 5x's as potent as Des the chlorine atom also increase blood & tissue solubility

Sevoflurane chemical characteristics

heavy fluorination decreases potency, but it is still 3x's as potent as Des because of heavy propyl side chain

Axillary block complications

hematoma (hold pressure for 3-5min) LAST

Valproic Acid (Depakote) s/e

hepatotoxicity thrombocytopenia (surgical bleeding - esp. in kids) Displace phenytoin from plasma proteins

When can succ cause a phase 2 block

high doses of Succ can cause a phase II block (high IV bolus or infusion) Dose > 7-9mg/kg 30-60 min of continuous exposure Fade with tetany and prolonged duration

Ramen Scatter Spectrometry

high power argon laser to produce photons. Scattered photons are measured in a spectrum that identify each gas

If ICP is elevated, CPP requires a ______________ MAP to maintain CPP

higher = if MAP is low w/ a high ICP you risk ischemia

How is rebreathing minimized with a Mapleson system

higher FGF smaller Vt longer expiratory time

Hyperbaric

higher density than CSF - sinks

What are required to prime a less compliant ventricle

higher filling pressures

Risks of cutting needles

higher risk of PDPH less tactile feel Needle more easily deflected More likely to injure cauda equina

glomerular filtration and protein binding

highly protein bound drugs will not be freely filtered. non-protein drugs will be freely filtered.

Slope of Dose response curve tell us ____

how many receptors must be occupied for a drug to have a clinical effect -a steep slope implies that most of the receptors must be occupied before the effect is noted

the only bone that does not articulate with another bone

hyoid

Gastrinoma (Zollinger-EllisonSyndrome)

hyper secretion of gastrin: excessive gastric acid secretion Diarrhea or steatorrhea typically a non-beta cell pancreatic tumor Surgical excision of the lesion is tx of choice in pt's w/out metastasis

Liver dx CV considerations

hyperdynamic circulatory state

What increases CMRO2

hyperthermia ketamine N2O (Hyperthermia >42 degrees denatures proteins and destroys neurons)

Diagnosis of Hypokalemic periodic paralysis

if muscle weakness follows a glucose-insulin infusion

Diagnosis of Hyperkalemic periodic paralysis

if muscle weakness follows oral potassium administration

0.1 MAC

impaired response to hypoxia (peripheral) does not impair response to PaCO2 (central)

Halothane hepatitis

impairment is largely attributed to decreased systemic blood pressure, as well as halothane specifically will impair hepatic blood flow even further through the abolition of the vasoconstrictor response to hypercarbia Hepatocyte hypoperfusion, hypersensitive immune response

hypobaric supine

in supine position it rises to lower lumber region in sitting position it rises toward the brain (bad)

Sevo affect on EEG

increase epileptiform activity

brainbridge reflex

increase in heart rate due to an increase in central venous pressure

Extrajuctional receptors reaction to NDNMB's

increased resistance = need to use higher doses

Hyperalgesia

increased sensitivity to pain caused by Remifentanil also by inflammation

A return pad that is too small ___________ the risk of thermal injury

increases

N2O effect on PVR

increases

Hyperkalemia

increases RMP, makes depolarization more likely, leads to arrhythmias

N2O affect on BIS

increases amplitude of high frequency activity and reduces amplitude of low frequency activity

Ketamine affect on EEG

increases high frequency cortical activity may confuse EEG interpretation

Affect of obesity and pregnancy on epidural space

increases intra-abdominal pressure -> causing engorgement of baston's plexus ->decreases the volume of the epidural space -> increased risk of needle injury of cannulation during neuraxial techniques

How do VIA protect the myocardium against iscemia

increasing myocardial blood flow in excess of metabolic demand

cholecyctitis

inflammation of the gallbladder cholecysectomy

Meningitis

inflammation of the meninges caused by viral or bacterial infection and marked by intense h/a, fever, sensitivity to light, and muscular rigidity • Contamination of equipment • Glass Particles • Coring of tissue

Function of IABP

inflates during diastole, increasing coronary perfusion and myocardial oxygen supply deflates during systole, reducing afterload & LV work

Old theory of anesthetic action

inhalation agents work at the lipid bilayer

Modern anesthetic theory

inhalation anesthetics interact with stereoselective receptors stimulate inhibitory receptors - GABA-A

Ehlers-Danlos syndrome

inherited disorder of collagen & procollagen — primarily your skin, joints and blood vessel walls. Coagulopathy -> spontaneous bleeding into the joints * AAA Avoid regional anesthesia & IM injections

Charcot-Marie-Tooth disease

inherited peripheral neuropathy. Presents as skeletal muscle weakness and wasting. Usually confined to lower third of legs, but can also affect the quadriceps, hands, forearms

opioid moa

inhibit pain transmission (afferent signals) in the substantia gelatinosa via the dorsal horn

Neurendocrine affects of neuraxial anesthesia

inhibition of afferent traffic from the surgical site diminishes the surgical stress response. ↓circulating catecholamines, renin, angiotensin, glucose, thyroid stimulating hormone, growth hormone

Provider factors that increase risk of pulmonary artery rupture

inserting catheter too far prolonged balloon inflation chronic irritation of vessel wall unrecognized wedging filling the balloon with liquid rather than air

Sphenopalantine ganglion block

inserting two qtips into the posterior wall of the nasopharynx

F(i)

inspired gas flow = determined by: -FGF rate -breathing circuit volume -circuit absorption

Where do spinal nerves exit the vertebral column?

intervertebral foramina

location where nerves exit spinal column

intervertebral foramina

Factors that cause an inability to predict CO

intracardiac shunt Tricuspid regurg

Acid in a base solution Base in an acid solution

ionized

Afib

irregular rhythm w/ no P wave Loss of atrial kick ↓CO atrial thrombus formation (stroke risk) Risk w/ RVR: reduces diastolic filling time, associated w/ severe reduction in CO (syncope, CP, SOB) Treatments: BB, CCB, Digoxin, anticoagulation Acute onset afib tx: cardioversion (100j) onset > 48h = need TEE b/f cardioversion to rule out thrombus New onset or undiagnosed afib is reason to cancel surgery Most common postop tachydysrhythmia = usually 2-4d postop

Most common cause of periop vision loss

ischemic optic neuropathy (ION) = inadequacy of blood supply to the optic nerve -not associated with pain -occur w/in 24-48h after surgery -caused by external compression of the glob (most common) or embolism (CPB) s/s: cherry red macula with surrounding pale retina

pancreatic endocrine function

islets of Langerhans release insulin and glucagon nonductal - released directly into blood stream αAlpha: glucagon βBeta: Insulin (~around 50units/day) δDelta: somatostatin (inhibits insuline release) (pp) Pancreatic Polypeptide cells (inhibits exocrine pancreatic secretion)

Flaw with context sensitive half-time

it only illustrates the time it takes for the drug to decrease by 50% in the CENTRAL compartment. This is why it does not necessarily predict the time to wake up. b/c it can redistribute into the fat and act like a sink for the drug.

Hyperkalemia treatment

iv calcium gluconate/ chloride insulin and glucose Hyperventilation Beta agonists bicarb lasix

Where does venous blood flow exit the brain

jugular veins

What drugs can prevent Remi-related hyperalgesia

ketamine or Mg sulfate

Most important clearing organs

kidneys liver organ independent (hoffmans, ester hydrolysis)

Constrictive Pericarditis s/s

kussmaul's sign (JVD during inspiration) ↑venous pressure = distended neck veins, hepatomegaly, Ascites, peripheral edema pulsus paradoxus Atrial arrhythmias d/t atrial distension Pericardial knock

Macroshock

larger current that is applied to the external body impedance of the skin offers high resistance -> takes a large current to cause vfib

Sciatic Nerve

largest nerve in the body actually 2 nerves contained in a sheath (common peroneal & tibial) Motor: posterior thigh Sensory: Most of the lower leg and foot

Metabolites of Des and Iso

metabolized into inorganic fluoride ions and trifluoroacetic acid (TFA) -much smaller amount than that of Halothane, but there is a possibility it could immune-mediated hepatic dysfunction - more likely in a patient w/ previous TFA exposure

Tramadol

metabolized to its M1 metabolite with is 6 x's more potent than parent compound. CYP2D6. Also contraindicated in children < 12-18y

Babinski sign

method to test the integrity of the corticospinal tract normal: plantar flexion (downward pointing of toes) abnormal: plantar extension (fanning toes)

Most common location of AAA rupture

left retroperitoneum -clot formation and tamponade effect at this location prevents rapid exsangination

Posterior borders of the epidural space

ligamentum flavum vertebral lamina

GABA receptors

ligand gated Cl- channels (hyperpolarization) - volatile anesthetics increase the duration the channel is open most important site of volatile anesthetic action

Acidic urine favors

like dissolves like Reabsorption of acidic drugs Excretion of basic drugs AAA: Acidic drugs are better Absorbed in Acidic urine You can acidify the urine to eliminate basic drugs (ammonium chloride, cranberry juice)

Meyer-Overton Rule

lipid solubility is directly proportional to inhaled anesthetic potency -the greater the lipid solubility, the lower the MAC -depth of anesthesia is dependent on the number of anesthesia molecules dissolved in the brain

Neuraxial opioids effect on the fetus

lipophilic will have greater effect b/c more cross into systemic circulation

What systems are unchanged by neuraxial anesthesia

liver and kidneys

What is Dibucaine

local anesthetic that inhibits PChE. It has no affect on atypical PChE. The number reflects the percentage of normal enzyme. The lower the amount of normal enzyme the longer muscle paralysis will last.

CTZ (chemoreceptor trigger zone)

located in postrema region of brainstem, not protected by BBB. Quick vomit reflex. Stimulated by emetics like opioids, dopamin, Serotonin, Histamine, ACh, Vestibular portion of CNVIII Inhibited by: Dopamine antagonists, 5-HT3 Antagonists, Histamine Antagonists, Anticholinergics, Propofol It stimulates the vomiting center

Hypocalcemia on EKG

long QT interval

long QT and Torsades treatment/prevention

long QT: BB or PPM Avoid SNS stimulation Torsades: Mg Sulfate or pacing to increase HR

Describe a Sphenopalantine ganglion block

long swab soaked in 1-2% lidocaine or 0.5% bupivicaine Advance through the nostril until you hit the back of the nasopharynx Leave in place for 5-10min

Wernicke-Korsakoff syndrome

loss of neurons in cerebellum brought on by thiamine deficiency

Hypobaric

lower density than CSF - rises

epidural volumes

lumber inj: 15mL for midthoracic block thoracic inj: 5mL No dosing until negative aspiration for CSF and blood.

Chylothorax

lymph in pleural cavity can be caused by thoracic duct puncture during left IF insertion

Ventilation strategy for cardiac tamponade

maintain spontaneous ventilation until tamponade is relieved - PP can impair venous return and decrease CO

How does EMI impair pacemaker function

makes myocardium more resistant to depolarization

development of new delta waves during anesthesia

may signify the brain is at risk for ischemia

efficacy

measure of intrinsic ability of drug to cause a clinical effect -height of the plateau on the y-axis -once plateau is reached, additional drug will not increase the effect it will just cause toxicity

Alpha Angle

measured point C normally 100-110 degrees

pulse contour analysis

measurement of maximum and minimum pulse pressure values over the respiratory cycle

Cricothyroid membrane

membrane between the cricoid and thyroid cartilages of the larynx -Membrane that is punctured during cricothyroidotomy Connects cricoid cartilage at C6 to the thyroid cartilage

Hippocampus

memory learning

Opioids that release histamine

meperidine, morphine, codeine, oxycodone

Opioids with active metabolites

meperidine: normeperidine morphine: M6G (M3G is inactive metabolite) Meperidine is the major problem and why it is not given for longer than 24-48h.

Laudanosine

metabolite of cisatracurium and atracurium renally excreted CNS stimulant: very high levels can cause seizures (esp in pts. with renal failure) NO neuromuscular blocking properties Atracurium produces more Mivacurium does not produce a metabolite

Why to use a Tuohy

minimizes the risk of dural puncture

3 phases of metabolism

modification conjugation elimination

Enantiomers

molecules that are mirror images of each other -R & S

characteristics of urinary retention w/ neuraxial opioids

more common in young males more common w/ neuraxial opioids vs other routes caused by inhibition of sacral parasympathetic tone reversed w/ naloxone

Right axis deviation

more positive than +90 +90 to +180 (more positive than 180 is extreme right)

Albumin

most abundant plasma protein t 1/2 is 3 weeks primary determinant of oncotic pressure measurement for protein synthesis (chronic not acute problems) negative charge primarily binds acidic drugs

Obstructive hypertrophic cardiomyopathy

most common cause of sudden death in young athletes Other names: Asymmetric septal hypertrophy, idiopathic hypertrophic subaortic stenosis Patho: LVOT is caused by hypertrophy of intraventricular septum & systolic anterior motion (SAM) of the anterior leaflet of the mitral valve

CYP 3A4

most important cytochrome in P450 enzyme - metabolized nearly 50% of all drugs Substrates: opioids, benzos, local anesthetics inducers: tamoxifin, barbituates, St. John's Wort, rifampin, ethanol, carbamazepine inhibitors: grapefruit, SSRI's, cimetidine, erythromycin, azole antifungals

Broca's area

motor control of speech

Frontal lobe

motor cortex

Feedback loop implicated in Parkinson's

motor cortex -> basal ganglia & cerebellum -> back to cortex via the thalamus (suppresses the motor cortex)

Ankle block complications

multiple injection sites - intravascular injection Do not use epi d/t ischemic complications in small spaces

3 types of neurons

multipolar: most CNS neurons pseudounipolar: dorsal root ganglia, cranial ganglia bipolar: Retina, ear

Nerve associated w/ bicep twitch response

musculocutaneous

White matter

myelinated axons - ascending & descending tracts dorsal, lateral and ventral columns

Primary site of local anesthetic action in spinal anesthesia

myelinated preganglionic fibers of the spinal nerve roots

myotome vs dermatome

myotome = ventral nerves dermatome = dorsal nerves

Secondary signs of AH

nasal stuffiness HTN -> H/A & blurred vision Malignant HTN -> Stroke, seizure, LV failure, dysrhythmias, pulmonary edema, and/or MI

Drugs that decrease MAC

need less gas -Acute alcohol intoxication -Lithium -IV anesthetics -Lidocaine -N2O -Opioids -Alpha-2 agonists -Hydroxyzine

What is the epidural space?

nerve roots, fat pads, blood vessels fat cells act as a lipophilic sink for drugs reducing their bioavailability bupivicaine > lidocaine & fentanyl > morphine

Batson's plexus

network of epidural veins that drain venous blood from the spinal cord and meninges. It passes through the lateral and anterior regions of the epidural space.

Grey matter

neuronal cell bodies in the CNS -processing center for afferent signals from the periphery -H shape of the spinal cord

Piezoelectric Crystals

new analyzer uses piezoelectric crystals detects inspired, expired, and breath to breath changes of a gas by incorporating a lipid layer on the crystal. Cannot identify multiple gases so not clinically useful.

Anesthetic mgmt of ALS

no benefit of one technique over another Succ can cause lethal hyperkalemia Sensitivity to nondepolarizing NMB's Bulbar muscle dysfxn increases risk of pulmonary aspiration Chest weakness reduces vital capacity & minute ventilation may need postoperative mechanical ventilation

non-ionized

no charge, lipid soluble, can pass thru membranes

Acid in an acid solution Base in a base solution

non-ionized

Drugs that can pass biological membranes

non-ionized If a drug passes a membrane and becomes ionized b/c of a different pH of that body compartment then it is trapped there.

Diffusion hypoxia

only occurs with N2O - fast nitrous diffusion out of the blood and into the lungs displaces oxygen in the alveoli. Cure is to run high oxygen levels at the end of a case -Gas containing areas of the body can contain up to 30L of N2O. This is eliminated from the body in 5 minutes after N2O is d/c'd

How does a subarachnoid hemorrhage result in death

obstructive hydrocephalus Rebleeding Vasospasm

Bainbridge reflex

occurs when mechanoreceptors embedded within the right atrial myocardium respond to an increase in pressure and stretch (distention of the right atrium). stimulates the vasomotor centers of the medulla and results in increased sympathetic input and heart rate. reflex can also influence a decrease in heart rate when heart is beating too fast.

Mallampati 3

only base of uvula

CVP waveform and mechanical events

reflection of pressure inside the RA 3 peaks: a,c,v 2 troughs: x,y

Complications of non-cutting

requires more force

myastehnia gravis: _______________ to Succ

resistant b/c there is reduced Ach nicotinic receptors at the NMJ -increase RSI dose 1.5-2mg/kg

Main treatment for alzheimer's

restore concentration of Ach cholinersterase inhibitors = increase pSNS tone (can see bradycardia, syncope, N/V) If anticholinergic is need use glyco (does not cross BBB) (prolongs Succ)

Cardiac oscillations capnography

result from heart beating against lungs more common in children

acute pericarditis

result of inflammation. does not restrict filling unless it leads to constrictive or cardiac tamponade Causes: infx (viral): most common cause, Dressler's syndrome (s/p MI), SLE, scleroderma, Trauma, Cancer (radiation)

Risk factors for difficult laryngoscopy/intubation

small mouth opening long incisors prominent overbite high, arched palate Mallampati III or IV Retrognathic jaw Inability to sublux jaw (mandibular protrusion test) short thick neck short tmd Reduced cervical mobility

Speed of induction is a function of __________________

solubility low solubility -> less uptake into blood -> ↑rate of rise -> faster equilibrium of FA/FI -> faster onset high solubility -> ↑ uptake into blood -> ↓rate of rise -> slower equilibrium of FA/FI -> slower onset

Parietal lobe

somatic sensory cortex

feed forward action of Ach

some of the Ach released into the synaptic cleft binds to the presynaptic receptor perpetuating release.

Anesthetic mgmt if aneurysm ruptures during procedure

reverse heparinization with protamine lower MAP into low/normal range

Chronic hypertension shifts cerebral autoregulation curve to the __________?

right -this helps the pt's brain tolerate a higher chronic BP, however this prevents the patient from tolerating BP's at the lower end of the autoregulation range. So instead of autoregulation ending at a BP of 50 mm Hg it will end at a higher BP the range may also become narrower with chronic hypertension

Where should transducer be leveled

right atrium / phlebostatic axis

SLE Anesthetic Considerations

risk of postextubation laryngeal swelling and airway obstruction (smaller ETT) risk for hypercoaguability & thrombosis (stroke, DVT, PE) Cyclosporine prolongs succ

What 2 blocks are needed to achieve complete anesthesia to the lower leg

sciatic n and lumbar plexus block

status epilepticus

seizure activity > 30 min or 2 grand mal seizures w/out regaining consciousness in b/w respiratory arrest -> hypoxia increased brain activity -> ↑CMRO2 treatment: phenobarbital, thiopental, phenytoin, benzos, propofol, general anesthesia

Normeperidine

seizures metabolite of meperidine = meperidine is de-methylated in the liver by CYP450 1/2 as potent as meperidine causes myoclonus reduces seizure threshold and ↑ CNS excitability (muscle tremors, twitches, seizures) avoided in dialysis patients and elderly

Sugammadex MOA

selectively bind to the aminosteroid NDNMB's -gamma-cyclodextrin made of 8 sugars in a ring. Encircles the nmb inactivating it. Decreases the free concentration of drug No major side effects

intervertebral discs

separate the vertebrae degeneration decreases the size of the intervertebral foramina and can cause nerve compression

Most common death for LVAD

sepsis -need prophylactic abx

TNS s/s

severe back and butt pain that radiates to both legs develops within 6-36 h and persists for 1-7 days

Main problem w/ cardiac tamponade and compensation

severely decreased SV and increased SNS tone Compensation = increase contractility and afterload = do not use drugs that decrease contractility or afterload - can cause cardiac collapse

Shape of epidural space

shallow anteriorly but deep posteriorly especially in the lumbar region

Vocalis muscle

shorten (relaxes) the vocal cord Innervation: RLN

interscalene block indications & landmarks

shoulder, arm, and elbow surgery Landmarks: Clavicular head of the sternocleidomastoid and cricoid cartilage

Oxycodone

significant variation and effectiveness depending on pt's metabolic genotype Duration of action: 2-4h pKa: 8.5 (7% nonionized) Metabolism: CYP2D6

isobaric

similar baricity to CSF - stays at injection site

Carcinoid tumors

slow growing malignancies composed of enterochromaffin cells usually found in the gastrointestinal tract -75% of tumors are found in the GI tract

Microshock

small amount of current applied directly to the myocardium -> smaller amount of current to induce vfib

When does atropine cause paradoxical bradycardia

small dose <0.5mg IV in adult due to inhibition of presynaptic M1 receptor on vagal nerve endings

Laryngospasm

spasm of the laryngeal muscles, causing a constriction. Caused by sensory stimulation by vagus nerve (external branch of SLN or RLN)

Most common source of post-spinal bacterial meningitis

streptococcus viridans

Clinical presentation of Cricoarytenoid arthritis

stridor, hoarseness, dyspnea -> airway obstruction edema or erythema of vocal cords risk for postextubation airway obstruction

Malignant hypertension increases the risk of?

stroke cerebral edema

dystrophin

structural protein of the cytoskeleton in skeletal and cardiac muscle cells. Helps anchor actin and myosin to the cell membrane Also allows extrajunctional receptors to populate the sarcolemma -> hyperkalemia (this is why people w/ DMD should not get Succ)

Which neuraxial opioid causes the most sedation

sufentanil

Arachnoid villi location

superior sagittal sinus

Trunks

superior: C5-C6 middle: C7 inferior: C8-T1

Cauda equina treatment

supportive

Techniques useful for a cannot intubate cannot ventilate situation

surgical cricothyrotomy percutaneous jet ventilation

Neuraxial opioids do NOT cause:

sympathectomy skeletal muscle weakness changes in proprioception

GI affect of neuraxial anesthesia

sympathetic inhibition allows unopposed parasympathetic stimulation -> relaxation of sphincters and increased peristasis

Part of the cardiac cycle when LVOT occurs

systole

The most common site of transtentorial herniation

temporal uncus - herniation of this area puts pressure on CNIII (oculomotor) and causes blown pupils, reflects pressure on the midbrain

Akinetic seizure

temporary LOC and loss of postural tone -can lead to a fall -> head injury -more common in children

saphenous nerve

terminal branch of femoral nerve Sensory to the medial aspect of the lower leg found next to the saphenous vein

Saphenous nerve block

terminal branch of the posterior division of the femoral nerve Sensory: medial aspect of the knee to the malleolus Motor: None Can be combined w/ popliteal block for total anesthesia

Level where the dural sac ends

termination of the subarachnoid space superior iliac spine: S2 (S3 in kids)

Solubility coefficient

the ability of the anesthetic agent to dissolve in the blood and tissues -higher -> more soluble -> slower onset/offset -lower -> less soluble -> faster onset/offset

dermatome

the area of skin innervated by the cutaneous branches from a single spinal nerve

Mean electrical vector

the average current flow of all the action potentials at a given point in time

Leak in the sample line during PPV

the beginning of the plateau is low b/c of dilution of alveolar gas as atmospheric air is aspirated into the sample line. Not seen with spontaneous breathing b/c there's no positive pressure May also occur in obese and pregnant patients

enzyme inhibition

the decrease in hepatic enzyme activity that results in reduced metabolism of drugs Enzyme inhibition=more risk for toxicity Ex. grapefruit is an enzyme inhibitor and can cause toxic drug levels.

Ceiling Effect

the dose beyond which there is no increase in effect. Additional dosing often leads to adverse effects

ED50

the dose that elicits the expected clinical effect in 50% of the population -measure of potency

LD50

the dose that will cause death in 50% of the population

Half time

the time it takes for 50% of the drug to be removed from the plasma Half times are really only applicable to a 1 compartment model which does not exist in real life - drugs distribute into and out of compartments at different rates

Systolic heart failure

the ventricle doesn't empty well -decreased EF w/ and increased EDV -Compensatory mechanisms: ↑RAAS, ↑SNS, ↑preload

For current to flow, ____

there has to be a voltage difference (driving pressure) across an impedance The impedance is a person

kinetic models of drug metabolism

there is a finite number of enzymes that can metabolize the drug

Why are steroids contraindicated w/ TBI

they cause hyperglycemia -> acidosis

Difference b/w right heart and left heart

thinner more compliant weaker

Bioavailability

the fraction of an ingested dose of a drug that gains access to the systemic circulation.

Blood gas solubility

the higher the solubility the slower the drug Stays dissolved in blood rather than moving into the brain

What does failure to capture mean?

the myocardium is more resistant to depolarization (pulse generator fires, but there is no depolarization)

Effect of PaCO2 on CBF

the pH around arterioles effects their diameter ↑PaCO2 (↓pH) causes vasodilation = for every 1mmHg increase in PaCO2 -> CBF increases 1-2mL/100g tissue/min

pKa

the pH at which the drug will exist in solution as 50 percent ionized and 50 percent non-ionized. All drugs are salts of a weak acid or base

What is the depth of anesthesia determined by

the partial pressure of anesthetic in the brain - NOT the volume percent

What happens to the partial pressure if the agent continued until it fully equilibrated to all body tissues

the partial pressure of each tissue would be equal

protein-binding effect

the portion of a drug that is bound is inactive because it is not available to the receptors This is only really an issue for drugs that have 90% or greater protein binding. Decreased protein levels or introduction of a drug that competes for protein binding could increase the levels of highly protein bound drugs. However, when there is an increase in unbound drug, elimination of that drug is increased. Highly protein bound drugs are eliminated more slowly

What distinguishes between a phase 1 and phase 2 block

the presence or absence of fade

Vapor pressure

the pressure caused by the collisions of particles in a vapor with the walls of a container vapor directly proportional to temperature ↑temp -> ↑vapor pressure

Plateau Pressure

the pressure in the small airways and alveoli after the target tidal volumes delivered. There is no airflow during this time so airway resistance does not figure in. Reflects the elastic recoil of the lungs and thorax during the inspiratory pause (no airflow)

What happens when a compliant airspace becomes a fixed airspace

the pressure starts to increase Compliant airspace: N2O increases volume Fixed airspace: N2O increases pressure

What is the defining mechanism of fade

the presynaptic Ach receptor. If new Ach is not mobilized through this mechanism the muscle contraction fades

why dose the cardiac impulse not move backwards

the previous tissues are in refractory

therapeutic index

the ratio between the therapeutic and lethal dose LD50/ED50 = THERAPEUTIC INDEX ED50 = Effective dose in 50% of population LD50 = Lethal dose in 50% of population -TD50 can be substituted for LD50 b/c it is not ethical to test the LD50 in humans

Pharmacokinetics

the study of the absorption, distribution, metabolism and elimination of drugs What the body does to a drug How the drug gets to its receptor and then how the drug leaves the body -drug dose and plasma concentration

first pass metabolism

the substance degradation of an orally administered drug caused by enzyme metabolism in the liver before the drug reaches the systemic circulation

spinal facet joints

the superior articular process of one vertebrae & the inferior articular process of the vertebrae directly above

Half-life

the time it takes for 50% of a drug to be removed from the body

Reason for priming the CPB

to de-air it

Organic Anion and Cation Transporters

transport proteins in proximal renal tubule actively secrete organic acids and bases into urine organic anion transporters: furosemide, thiazide diuretics, and penicillin organic cation transporters: morphine, meperidine, dopamine

Aqueduct of Sylvius

transports CSF b/w 3rd and 4th ventricle

Anesthetic management of constrictive pericarditis

treatment: Pericardiotomy CO is dependent on HR - avoid bradycardia Preserve HR and contractility -ketamine and pancuronium -use volatiles w/ caution -opioids, benzos and etomidate ok Maintain afterload Aggressive PPV can decrease venous return and CO

Large V waves

tricuspid regurgitation Acute increase in intravascular volume RV papillary muscle ischemia

tic douloureux

trigeminal neuralgia (CN V) Excruciating pain in the face

Supraclavicular block level

trunks/divisions

Methods to reduce cerebral mass

tumor debulking hematoma evacuation

T10 dermatome

umbilicus

Total spinal

unresponsiveness accompanied by cardiac and respiratory compromise. • Rapid Onset - one of first signs is nausea • Ascends to Cervical Levels • S/S: Restlessness, Hypotension, Bradycardia, Apnea • Treatment: ABCs (ACLS), establish airway, start pressors

Isoelectric line

use PR interval to find isoelectric. This can be used as a reference point to find the J point at the end of the QRS

Fascia Iliaca Block

used for hip fractures You should feel 2 pops (fascia iliaca & fascia lata) Easy to find w/ landmarks - do not need US or nerve stim LA is deposited inferior to the fascia iliaca by superior to the iliopsoas muscle

Thermodilution method

used to measure CO inject in < 4 seconds Average of 3 injections High CO = injectate travels faster, small curve Low CO = injectate travels slower, large curve

Laryngospasm Treatment

• 100% Oxygen • Continuous positive pressure ventilation-up to 40 cm H2O • Suction all blood and foreign material with yankauer suction • Laryngospasm notch/Larson maneuver • Drugs: Lidocaine, 1 mg/kg, Propofol 0.5-1 mg/kg IV • If obstruction persists, break spasm with Succinylcholine-SaO2 starts to drop in the low 80's, 0.2-0.5 mg/kg IV or sublingual 2-4 mg/kg IM. Give Atropine 0.02 mg/kg w/ Sux for peds

Epidural catheter measurement designations

• 2 lines = 10cm • 3 lines = 15cm (5cm in the epidural space) • 4 lines = 20cm • Dark Band = Exiting Needle - the catheter has reached to needle tip The needle is 9cm

Epidural Abscess

• Back pain with fever • Tx: Abx and surgical decompression • Prevention: Sterile • Remove catheters after 96 hours

PDPH treatment

• Blood Patch - Gold Standard-90% success • Sphenopalatine Ganglion Block - qtip through nasal passage and drip lidocaine down it. -Caffiene -NSAIDs -bedrest -hydration

Spinal Local Anesthetics

• Bupivacaine • Tetracaine • Chloroprocaine

What does the ligamentum flavum join

• Connects the lamina with the facet joints. Helps maintain posture • Typically 3-5mm thick - thickest in the lumbar section

PDPH MOA

• Decrease in CSF • Brain/Brainstem drop into the Foramen Magnum • Tug on Meninges • Vasodilatory mechanism from lack of CSF

Other effects

• Decreased thermoregulation • Decreased stress response

Epidural or Spinal Hematoma

• Devastating: Can lead to paralysis • Patient Selection is key to prevent • Thrombophylaxis (follow protocols) • Thrombocytopenia (check PLT) • Neuro checks are key • Tx: Referral for rapid decompression - Goal <8 hours after symptoms present

Pro's of spinal/epidural

• Narcotic sparing and the subsequent sequlae • Blunt the stress response • In certain populations decrease blood loss • Can do cases awake (Cesarean, TURP) • Less overall medication usage (N/V, alertness) • Avoid airway manipulation and drugs associated

Tx of CV effects

• Fluids • Alpha or Beta Agonists (Ephedrine, Phenylephrine) • 5-HT3 Antagonists (zofran) • Atropine if a High Spinal Anesthetic

Chloroprocaine - spinal

• Great for Outpatient Surgery • Duration 1-1.5 hours • 2% or 3% • Dose (2%) - 2-2.5mL (40-50mg) • Off Label Use

Troubleshooting

• Hitting bone-> Walk up or down • No CSF-> Correct placement • Half my drug sprays out - do not redose • I've hubbed my needle • I can't access this space?-> New space or Paramedian approach • ALWAYS try repositioning the patient first

Touffier's Line

• Intercristal Line • Top of iliac crests • Intersects ~L4 go into L3, L4, L5

What does the supraspinous ligament join

• Joins the apexes (tips) of the spinous processes • Major ligament in cervical & thoracic spine

TNS - transient Neurological Symptoms risk factors

• Lidocaine (5%) • Lithotomy position • Ambulatory surgery • Total knee arthroplasty

PDPH s/s

• Light Sensitivity • Postural H/A - lying down eliminates h/a (pneumocephalus is the only other differential) • N/V -improved by recumbency -accompanied by tinnitus and photophobia -usually bilateral - usually frontal or occipital -They are usually self-limiting

Technique - Epidural

• Localize selected space • Insert Epidural Needle 1-3cm • Remove stylet • 1 hand vs 2 hand advancement • Attach Loss of Resistance Syringe • Air or Sterile Saline • Advance by mm until LoR is appreciated • Remove syringeterm-139 • Thread Catheter • Test Dose (Epi?)

Spinal technique

• Localize selected space • Insert introducer needle • Advance chosen spinal needle • Feel for "pops" - not always present • Remove stylet • Assess for CSF • Attach syringe • Aspirate - look for swirl • Inject chosen medication Do not need to worry about LAST because there is no vasculature in subarachnoid space

Pulmonary effects

• Loss of accessory/intercostal muscles • Loss of perception of breathing • Small decrease in VC • Phrenic Nerve (C3-C5) anesthetized if total spinal - diaphragm • Impaired cough

Opioids - spinal

• Morphine: Little analgesic benefit above 200mcg (but S/E increase): Pruritis, N/V • Dilaudid: 70-100mcg, Less Pruritis and N/V • Fentanyl: 10-20mcg (typically don't use) • Sufentanil: 5-10mcg