APEX Misc. Topics
What are the 3 most common causes of intraop anaphylaxis?
#1 NMB - Succ most common #2 Latex- HIGH risk groups: spina bifida/myelomeningocele, atopy, health care workers & alx to banana, kiwi, mango, papaya, pineapple & tomato #3 Antibiotics (beta-lactams = most common) ALSO: protamine, contrast media, colloids, opioids, hypnotics & LA)
What structures are anesthetized with a celiac plexus block? what is it good for? a/e?
- CP innervates upper abd EXCEPT for left side of colon - CP does NOT innervate pelvic organs *useful in cancer patients of UPPER abd organc use in: distal esophagus, stomach, liver, pancreas, small intestine, & colon (EXCEPT descending colon) a/e: orthostatic HOTN, retroperitoneal hematoma, hematuria, diarrhea, AAA dissection, back pain & retrograde migration of injectate (PROB if neurolytic is used)
List 7 situations in which induced hypothermia is useful
- Cerebral ischemia - Cerebral aneurysm clipping - TBI - CPB - Cardiac arrest - Aortic cross clamp - CEA
What structures are anesthetized with a superior hypogastric plexus block? what is this good for? a/e?
- useful in cancer patients for pain of the PELVIC organs ex: uterus, ovaries, prostate, descending colon a/e: retrograde migration of the injectate (prob is neurolytic is used)
What 5 physiologic changes can occur with TQ deflation?
- ↑ EtCO2 - ↓ core body temp - ↓ BP - ↓ SvO2 (SaO2 = usually normal) - metabolic acidosis restores BF to extremity = relative DEC in circulating blood volume & products of cellular hypoxia enter systemic circulation
What 3 types of surgery are well suited for a thoracic paravertebral block? & how is it done?
-Breast surgery -Thoracotomy -Rib fracture LA is injected into the paravertebral space (POTENTIAL space) = targets the ventral ramus as it exits the vertebral formen = unilateral sensory & sympathetic block (visceral) along that specific dermatome **ESSENTIALLY single shot unilateral epidural block -EACH dermatome must be anesthetized
what are the 2 contraindications for metoclopramide
-Parkinsons disease → dopamine antagonist effect (so also droperidol, haloperidol & prochlorperazine***signif sedation) -Bowel obstruction → prokinetic agent effect
Describe the 4 consequences of the capillary leak that occurs after a burn injury & when does the magnitude of a leak become greater with?
1. Inc. vasc. perm => edema 2. Loss of protein-rich fluid to interstitial space => ↓ plasma oncotic P 3. Loss of intravasc vol => hypovolemia + shock 4. Hypovolemia = hemoconc GREATER leak w/ a major burn, inhalation injury or a delay in resuscitative efforts
What are the 4 mechanisms of heat transfer? Rank them from least to most important
1. Radiation - Infrared 60% **forced air warmer = MOST effective method of periop warming 2. Convection - Air 15-30% -aka "wind chill" & laminar flow = increases the amount of heat lost to convection 3. Evaporation - H20 loss 20% -fxn of exposed surface area & relative humidity 4. Conduction - Contact < 5% -amount of heat lost = fxn of temp gradient & thermal conductivity of the object
FIRE SAFETY What are the 5 steps to be taken when fire is present in the OR
1. STOP ventilation & d/c ETT 2. STOP flow of all gases 3. Remove other flammable material from airway 4. Pour H20 or saline into airway 5. If can't put out fire on 1st try, use extinguisher
What are the abdominal structures encountered in a TAP block from superficial to deep? & 3 landmarks that form the triangle of Petit? complications?
1. SubQ 2. External oblique 3. Internal oblique insert needle in this plane (2 pops if blind) 4. Transverse abdominis 5. Peritoneum 3 landmarks: -external oblique -latissimus dorsi -iliac crest 15-20 mL of LA is ultra sound = a few cm superior & parallel to the iliac crest complications: peritoneal puncture & liver hematoma
what are the 3 causes of drug induced hyperpyrexia other than MH?
1. neuroloeptic malignant syndrome 2. serotonin syndrome 3. anticholinergic poisoning (red hot, delirium, mydriasis NO muscle rigidity)
What is the rate of cross-reactivity btwn PCN and cephalosporins? A patient w/ a PCN allergy may receive a cephalosporin if the PCN reaction fits what 2 qualifications:
10% (Apex claims this is a gross overstatement) d/t cross-reactivity based on the R1 side chain 3rd & 4th generation cephalosporins = LOWEST rate of cross reactivity 1. Rxn was NOT IgE mediated - anaphylaxis, bronchospasm, urticaria 2. Rxn did NOT produce exfoliative dermatitis - SJS
When are the fluid shifts greatest after a burn injury? & when do they stabilize how should you replace them? 2 formulas & 1st 24 hr & 2nd 24 hours
12 hrs - explains why fluid req higher in 1st 24 hr 24 hrs parkland formula: Crystalloid ONLY - 4mL LR x %TBSA burned x kg - 1/2 vol in 1st 8hr - 1/2 vol in next 16hr THEN give D5W **IF colloid = ONLY give 0.5% + % TBSA x kg Modified Brooke - 1st 24 hours: Crystalloid - 2mL LR x %TBSA burned x kg the rest = same as parkland **THESE underestimate the fluid requirements of infants & children
what structures does 1st degree burn penetrate? s/sx? 2nd? 3rd? 4th?
1st (superficial) epidermis only, stinging, tender & sore 2nd (partial thickness) superficial dermal = epidermis to upper dermis deep dermal = epidermis to lower dermis VERY painful 3rd (full-thickness) complete destruction of epidermis & dermis NO sensation b/c nerve endings are obliterated 4th (full-thickness) extends to muscle & bone NO sensation b/c nerve endings are obliterated
What are the stages of ECT, s/sx? & how long they last?
1st = tonic phase ↑ PNS lasts 15 seconds s/sx: - Bradycardia - HoTN - ↑ secretions (oral + gastric) 2nd = clonic phase ↑ SNS activity lasts several minutes s/sx: - Tachydysrhyth - HTN - ↑ intragastric P - ↑ CBF - ↑ ICP - ↑ IOP
How long must the TQ remain inflated after a Bier block? Why? What TQ pressure is required for a Bier block on the UE? LE? what about pneumatic tourniquet pressures for UE? LE?
20 minutes after LA injected Premature release can lead to sz/cardiac arrest Bier UE = 300 mmHg LE = 300 mmHg or 2x over SBP whichever is higher MAX inflate = 2 hours (pain @ 45-60 min) UE 70-90 over SBP LE 2x SBP
CO binds to Hgb with what affinity of O2? what type of acid-base imbalance occurs? why is pulse ox not accurate? tx?
200x affinity than O2 CO shifts oxyhgb dissociation curve to the L oxidative phosphorylation is also impaired inadequate o2 delivery & utilization causes metabolic acidosis cherry red blood pulse ox is NOT accurate b/c cannot diff between HgbO2 & HgbCO SpO2 may give a falsely elevated result tx: 100% fi02 & hyperbaric chamber
Which 3 burn types require a skin graft?
2nd degree - deep 3rd degree 4th degree
What dose of Ketorolac is equivalent to 10mg Morphine IV? how long can it be taken for?
30mg taken for 5 days
Shivering ↑ VO2 how much? and ↑s the risk of what? how much does VO2 ↓ for every 1 C drop in temp
400 - 500% ↑ risk of: Myocardial ischemia & infarction for every fall in temp by 1 C = VO2 is ↓ by 5-7%
what are 3 anesthetic agents that help with PONV besides the standard 6)
6 norm: 5-HT2, NK-1 antagonists, dopamine antagonists, antihistamines, anticholinergics & steroids) propofol - 10-20 mg midazolam - d/t DEC DA activity in CTZ ephedrine 25 mg IM = by maintaing BP & cerebral perf usion pressure
what is hypOthermia defined as? What are 5 CV effects of intraop hypothermia?
< 36 C (pt regulates core temp between 36.7 -37.1 C -SNS stimulation -Oxyhgb shift LEFT -VasoC + ↓ PO2 -Coagpthy + plt dyfxn -Sickling of hgbS pharmacologic -Slowed drug metabolism = prolonged fx -Inc. solubility of volatile agents = prolonged emergence
What are the 6 ABSOLUTE contraindications to ECT What are the 5 RELATIVE contraindications?
Absolute 1. MI < 6 mo. 2. Crani < 3 mo. 3. Stroke < 3 mo. 4. Brain tumor 5. Unstable cervical spine 6. Pheo Relative 1. Pregnancy 2. Pacemaker/ICD 3. CHF or severe pulm disease 4. Glaucoma 5. Retinal detach
What are 2 ways to diminish the histamine release & HoTN d/t vanc admin?
Admin at 10-15mg/kg over 1 hr Give benadryl 1mg/kg + cimetidine 4mg/kg 1 hr preop
What are the urine output goals for a burn patient? adult vs child BP goals? HR? base deficit? o2 delivery index? mixed venous oxygen tension?
Adult: > 0.5mL/kg/hr Child: >1mL/kg/hr high voltage electrical injury > 1-1.5 mL/kg/hr (b/c myoglobin is nephrotoxic) Adult MAP > 60 mmHg infant SBP > 60 mmHg child SBP 70- 90 +(2x age in yrs) HR : 80-140 (age dependent) base deficit < 2 o2 delivery index : 600 mL O2/min/m^2 mixed venous oxygen tension (PvO2) 35-40 mmHg
Administration of which colloid should be avoided during the first 24 hours of a burn injury? Why? what suggest inadequate volume resuscitation in the first few days after a burn injury?
Albumin - it is lost to interstitial space INC Hgb = suggets inadequate volume resuscitation
What is gastric barrier pressure? Why is it important? what is barrier pressure reduced by?
Barrier P = LES Pressure - intragastric pressure Determines likelihood of GER Higher barrier P = lower chance of GERD barrier pressure reduced by ↓ LES tone ↑intragastric pressure
What are the 3 unique anesthetic considerations w/ stabismus sx?
strabismus sx = corrects the misalignment of extraocular muscles & re-establishes the visual axis 1. Inc. risk of MH 2. Inc. risk of PONV 3. Inc. risk of oculocardiac reflex (afferent CN V + effect CN X)
what is the most common source of bloodstream infection in the hospital? best method of prevention?
CVC = most common source of blood stream infection CDC = says chlorohexidine = preferred method of skin prep alcohol = flammable & MUST dry for 2 min (consider this when draping pt for sx)
what type of ett should be used with a CO2 laser? Nd:Yag laser?
CO2 = use LaserFlex tube Nd:Yag use Lasertubus
What is the role of COX-1 enzyme in the arachadonic acid cascade & what does inhibition cause? what is the role of COX-2 enzyme in the arachadonic acid cascade & what does inhibition cause?
COX -1 - always present, maintains normal physio fxn (GI mucosa, platelet, renal blood flow) inhibition = - impaired plt fxn - gastric irritation - dec renal blood flow COX-2 = - expressed during inflammation (inducible) (pain & fever) inhibition - analgesia (ceiling effect) - anti-inflammatory - antipyretic
what chemotherapeutic agent is different from the rest? and why?
MOST chemotherapeutic agents cause bone marrow suppression & thrombocytopenia BUT bleomycin does NOT
Anaphylaxis cardiac s/sx? respiratory s/sx? 4 skin s/sx? GI s/sx?
Cardiac: HoTN Tachycardia Arrhythmia Cardiac arrest RR: -Bronchospasm= - Dec. ETCO2 - Dec SaO2 - Inc. PIP -Laryngeal edema- mucous production Skin: -Flushing -Urticaria - hives -Erythema -Pruritis GI: Abd cramping N/V Diarrhea
What is the etiology of glaucoma? open angle cause? closed angle?
Chronically elevated IOP leads to retinal artery compression open angle = d/t sclerosis of trabecular meshwork impairs aqueous humor drainage closed angle = d/t closure of anterior chamber - creates mech outflow obstr
Cisplatin belongs to what drug class? What are its 2 main side effects? Vincristine + Vinblastine belong to what drug class? What is their main side effect? Bleomycin + Doxorubicin belong to what drug class? What are their main side effects? 5-fluorouracil + Methotrexate belong to what drug class? What is their main side effect? tamoxifen use and s/e?
Cisplatin = Alkylating agents - acoustic nerve injury - nephrotoxicity Vincristine + Vinblastine = Tubulin-binding drug - Peripheral neuropathy Bleomycin + Doxorubicin = Antitumor antibiotics Bleomycin = pulmonary fibrosis (keep FiO2 < 30%) Doxorubicin = Cardiotoxic 5-fluorouracil + Methotrexate = antimetbolite -bone marrow suppression **these can cause ulceration of mucus membranes = mucositis - so avoid oral airway, nasal airway, LMA or esophageal probe tamoxifen = selective estrogen receptor modulator ONLY For tumors that express estrogen receptors s/e: hot flashes & ↑ risk of endometrial cancer
What is the wavelength of the CO2 laser? type of surgery? structures damaged? eye protection? What is the wavelength of the Nd:Yag laser? type of surgery? structures damaged? eye protection? What is the wavelength of the Ruby laser? type of surgery? structures damaged? eye protection? What is the wavelength of the Argon laser? type of surgery? structures damaged? eye protection?
Co2 wavelength -10,600um -used in oropharyngeal & VC sx -damages the cornea -use CLEAR lens for protection Nd:Yag wavelength -1,064 um -used in tumor debulking & tracheal sx -damages the retina - use GREEN lens for protection Ruby wavelength -694 um -used in retinal sx -damages the retina - use RED lens for protection Argon wavelength -515 um -used in vascular lesions -damages the retina -use AMBER goggles
fat embolism syndrome cause risk fx s/sx tx
MOST common w/ long bone trauma In 1st 72 hr ***so VERY important to stabilize Risk: pelvic fracture, femoral fracture & instrumentation of femoral medullary canal Triad: RR insufficiency (hypoxemia, b/l infiltrates on CXR, ARDS) Neurologic involvement (confusion to coma) Petechial rash (skin of neck & axilla, oral mucosa, conjunctiva) Tx- supportive some say corticosteroids help
What are 3 drugs used to treat postop shivering
Meperidine - kappa Clonidine - alpha2 Dexmedetomidine - alpha2
Monocytes have what role? Lymphocytes have what role
Monocytes: -Phagocytosis -Release cytokines -Present pieces of pathogens to T-lymphocytes Lymphocytes B - humoral immunity - produce antibodies T - cell mediated immunity - no antibody production
Explain the 3 stages of intraop heat transfer
Most heat lost in Phase I during 1st hour of anesthesia w/ anesthesia (GA, spinal or epidural) = impair the thermoregulatory response in the hypothalamus to prevent shivering, cause vasodilation ***only a small amount of heat is lost to the environment during phase 1
what is neuroleptic malignant syndrome caused by? s/sx? tx?
NMS = caused by dopa depletion in basal ganglia & hypothalamus OR withdrawal from dopamine agonists **DOES NOT develop acutely -d/t dop antagonists metoclopramide haloperidol chlorpromazine resperidone s/sx: muscle rigidity (like a lead pip) muscle necrosis rhabdo myoglobinuria ANS instability normal pupils restored w/ bromocriptine, dantrolene, supportive care & ECT ( can give sux)
What is the tx for intraop anaphylaxis
D/c culprit Airway support: ↑firO2 Epi - 5-10 mcg if HoTN - 0.1-1 mg if CV collapse **EPI tx by preventing degranulation, providing CV support & dilates the airway LIBERAL IVF - Crystalloid 10 - 25 mL/kg - Colloid 10mL/kg H1 blocker - benadryl 0.5 - 1.0 mg/kg H2 blocker - ranitidine 50mg - famotidine 20mg Hydrocortisone - 250mg IV (prevents delayed release of inflamm compounds, does not have acute fx) Albuterol for bronchospasm Vasopressin for refractory HoTN - 0.01 unit/min
What 10 factors ↓ IOP? what 11 factors ↑ IOP? what 3 things have min/no effect?
DEC w/: - hypocarbia - dec. CVP - dec. arterial BP - volatiles - N20 - Nondepol NMB - propofol - opioids - benzos - hypothermia INC w/: - hypercarbia - inc. CVP - inc. arterial BP - hypoxemia - DL - strain/cough - succinylcholine (↑ IOP for 5-15 mmHg for up to 0 min) - N20 (if SF6 bub) - T-berg - prone - ext compression by mask anticholinergics do NOT ↑ IOP LMA = min effect on IOP ketamine +/- effect on IOP but does cause nystagmus &blepharospasms = AVOIDED in eye sx
What are the 5 pt risk factors for PONV? What are the 5 sx risk factors for PONV? What 3 pediatric procedures are associated with a higher incidence of PONV?
Female Nonsmoker Hx motion sickness Previous PONV Young sx: Duration > 1 hr GYN Laparoscopy Breast Plastics peds: Strabismus correction Orchiopexy T&A
Name the 3 ingredients required for a fire Give examples of each
Fuel - ETT - Drapes -surgical supplies Oxidizer - O2, N20 Ignition source - electrosurgical cautery, laser - Laser
What are the 5 herbal supplements that ↑ bleeding risk
Garlic (antiplatelet, tx HTN & hyperlipidemia, ↓ glucose) Ginger (tx nausea) Gingko biloba (anti-aging & tx poor circulation) Ginseng (antixoident)- can also ENHANCE SNS effect of sympathomimetics & cause hypOglycemia Saw palmetto (tx BPH)
What are the 5 most important GI hormones? site of production? stimulus? their role?
Gastrin -G cells in the stomach produce it -stimulus = food in the stomach -↑s gastric acid secretion & ↑pepsinogen secretion (converted to pepsin in the presence of stomach acid & aids in protein digestion) Secretin -made in S cells of the sm intestine -stim by acid in the duodenum -↑pancreatic bicarb secretion & liver to excrete bile ↓ gastrin production Cholecystokinin made in I cells in the sm intestine -stim by food in duodenum ↑gallbladder contraction (bile release) ↑pancreatic enzyme secretion - ↓ gastric emptying Gastric inhibitory peptide -made in K cells (sm intestine) - stim by food in duodenum SLOWS gastric emptying ↑insulin release ↓ gastric acid secretion Somatostatin -made in D cells (in pancreatic islet, stomach & sm intestine) -stim by food in gut, gastrin & CCK - UNIVERSAL off switch stop all GI function (enzyme & motility) **tx carcinoid tumor
Which 3 WBC types are granulocytes? Which 2 WBC types are agranulocytes?
Granulocytes: -Neutrophils -Basophils -Eosinophils Agranulocytes: -monocytes -lymphocytes
What are the 3 functions of the H1 receptor? What are the 2 functions of the H2 receptor? Arachidonic acid metabolites & their effects
H1: 1. Vasodilation 2. Inc. vascular permeability 3. Smooth muscle contraction H2: 1. Cardiac stim (tachyC) 2. Gastric acid secretion Arachidonic acid metabs: leukotrienes & prostaglandins = BOTH bronchoconstriction & vasodilation
What 5 anesthetic risk factors are associated with a higher incidence of PONV?
Halogenated anesthetics N20 > 50% Opioids Etomidate Neostigmine
what is the most common s/e of prophylactic abx? okay w/ preggo? any contraindicated?
INCLUDING cephalosporins = pseudomembranous colitis **MOST abx cross the placenta = can impact fetal development CONTRA: chloramphenicol, erythromycin, fluoroquinolones & tetracyclines ***ALL inhibit rNA synthesis , flouroquinoles = DNA synthesis
How do you calculate Intraocular Perfusion Pressure (IPP)? what are the determinants of IOP? what is norm?
IPP = MAP - IOP Globe is a NONcompliant compartment SO IOP determined by: 1. choroidal blood volume 2. aqueous fluid volume 3. extraocular muscle tone Normal IOP = 10 - 20 mmHg
What are the 2 herbal supplements that ↓ MAC
Kava kava (anxiety, ↑s GABA) Valerian (anxiety ↑'s GABA, abrupt stop = withdraw)
What does LASER stand for? & how is it different from ordinary light?
Light Amplification by Simulated Emission of Radiation Diff from regular light: 1.Monochromatic - single wavelength 2.Coherent - light oscillates in the same phase 3.Collimated - light exists on as a narrow parallel beam
Lithium effect on ECT process? Pt on MAOIs?
Lithium = prolongs the DOA of sux & NDNMBD pt on MAOIs who get indirect acting sympathomimetics = can experience HTN crisis
What is the difference btwn long and short wavelength lasers?
Long: - absorb more H20 - NO deep tissue penetration Short - absorb less H20 - penetrate deep tissue
What are the 2 most common causes of death r/t ECT?
MI Dysrhythmias ***BUT pt w/ CV dz can have ECT if their hemodynamics are well managed
What is complex regional pain syndrome (CPRS) risk? What are the 2 types of CRPS? tx (5)
Neuropathic pain w/ autonomic involvement risk: female, previous trauma or previous sx Type I - reflex sympathetic dystrophy Type II - causalgia**ALWAYS preceded by nerve injury (NOT type I) tx: -ketamine infusion -memantine (an NMDA antagonist) -gabapentin -regional sympathetic blockade -physical therapy
Neutrophils fight what? Basophils are part of what rx? Eosinophils defend against what?
Neutrophils: Fight bacterial + fungal infx Make up 60% of all WBCs Basophils: -Essential component of hypersensitivity rxns -Release histamine, serotonin, heparin, bradykinin -Epi prevents degran by binding to b2 receptors on cell membrane eosinophils = defend against parasites
Where is the vomiting center located? & What are the 3 major sensory inputs to the vomiting center? & their receptors?
Nucleus tractus solitarius in the medulla sensory inputs: -GI tract -Vagus n. (5-HT3 & NK1) -CTZ - Area Postrema (5-HT3, NK-1, DA-2 & noxious chemicals -Vestibular apparatus (H1 & M1) give scopolamine > 4 hr before induction ***NK1 = Aprepitant = block substance P in CTZ (PO 40 mg)
What is post-retrobulbar block apnea syndrome? other probs w/ retrobulbar block?
Optic nerve is the only CN that is part of the CNS LA injected into optic sheath goes direct to brain via the optic chiasm = anesthetizes CN II & III on the OPPOSITE side of the block = contralateral amaurosis (blindess) Think of it like giving an SAB in the optic sheath LA = reaches brainstem = can cause apnea (post-retrobulbar block apnea syndrome) evident in 2-5 min resolves in 15-20 min BUT can last 1 hr **watch contralateral pupil to assess for apnea syndrome if starts SMALL and gets LARGE anticipate needing CP support
what drugs & conditions prolong ECT seizure duration? (6) shortens it?(8) no effect (3)
Prolong -etomidate**myoclonus & ↑risk of PONV & MORE HTN after ECT -ketamine - ↑SNS and prolongs recovery -alfentanil + propofol -aminophylline -HypOcarbia - hypERvent decrease -propofol (also blunts hemodynamic response) -midazolam -lorazepam -fentanyl -lidocaine -hypOvent -hypERcarbia -hypOxia NO EFFECT: -methohexital****gold standard b/c no effect & fast recovery -precedex -clonidine -esmolol (used to blunt SNS)
Where is the P6 acupressure point and why is it important?
Reduces PONV
what is the protocol to reduce the incidence of periop sx infection? and the 7 measures?
SCIP protocol - surgical care improvement project 7 measures -a prophylactic abx admin w/in 60 min of incision (vanc = 2 hours) -choice of abx determined by site of sx -prophylactic abx discontinued w/in 24 hr of sx (48hr for cardiac) -cardiac pt MUST have glycemic control < 200 mg/dL -postop wound infection = dx during initial hospitalization -sx pt receive appropriate hair removal -colorectal pt are normothermic upon arrival to PACU (> 36 C)
what herbals can cause serotonin syndrome?
St. Johns Wort (tx depression) -INDUCEs CYP 34A (↓ serum level of warfarin, protease inhibitors & digoxin) -interaction w/ MOAIs &/or meperidine = serotonin syndrome -can prolong DOA of anesthetic agents Ephedra (Ma Haung) - a diet aid, athletic enhancer & nasal decongestant -interacts w/ MAOIs = serotonin syndrome -sympathomimetic effects - & catecholamine depletion w/ long term use
When is Succinylcholine safe to give to a burn patient? What happens after this window of opportunity? How should the dosing of a non-depolarizing NMB be adjusted for a burn patient?
Succ safe w/in 1st 24 hrs After 24 hrs = lethal hyperkalemia NDNMB Increased 2 - 3 X b/c there are more receptors
ocular gas bubble placement reason? types ? and avoidance of n20?
Sulfur hexafluoride = placed OVER retinal during retinal detachment, vitrectomy & macular hole repair N20 = can expand SF6 bubble = compromise retinal perfusion & cause permanent blindness so AVOID 15 min BEFORE place bubble & 7-10 days AFTER bubble is placed -silicone oil is used- NO days avoid N20 -air bubble is used- 5 days avoid N20 -perfluoropropane (C3F8)- 30 days avoid n20
What is a TAP block good for? what levels does it cover?
T9 - L1 GOOD for: General, GYN, Urologic b/l TAP for midline incision or laparoscopy
How is burn severity calculated? in kids?
Total body surface area (TBSA) Head = 10% RUE = 9% LUE = 9% Front trunk = 18% Back trunk = 18% RLE = 18% LLE = 18% Pernieum = 1% kids: palm w/out finger = 1% TBSA head = 19% (9.5 % front & 9.5% back) arms 9.5 & 9.5% legs 15% each front 16% & back 16% **every year of age > 1 up to 10 yo = ↓ head surface area by 1% & ↑ each leg by 0.5 %
What are the 4 types of hypersensitivity reactions? their etiology & path
Type I - Immediate etiology anaphylaxis & Extrinsic asthma Antigen + antibody interaction in pt who has been previously sensitized to the antigen Type II - Antibody mediated IgG + IgM antibodies bind to cell surfaces or extracellular regions = activates complement cascade etiology ABO-incompatibility HIT Type III - Immmune complex med Immune complex is formed & deposited into pt's tissue **** NORM these complexes are cleared from the body etiology -Snake venom rxn -Protamine-induced VasoC Type IV - Delayed -Rxn delayed at least 12 hr after exposure etiology -Contact dermatitis -Graft vs. Host Dz -Tissue rejection
What are 2 acceptable alternative abx if a patient's PCN rxn is severe enough to disqualify them from receiving a cephalosporin?
Vanc Clinda
What syndrome is gastrin commonly associated with?
Zollinger-Ellison - gastrin secreting tumor = ↑ stomach acid = gastric ulceration
Why is a burn patient at risk for abdominal compartment syndrome? dx criteria? (4)
abd compartment syndrome d/t aggressive fluid resuscitation Intra-abd HTN defined as: IAP > 20cmH20 AND evidence of organ dysfxn (HD instability, oliguria, inc. PIP) tx: NMB, sedation, diuresis & abdominal decompression via laparotomy
acetaminophen MOA, use and toxicity
acetaminophen = analgesic, antipyretic NOT an anti-inflammatory MOA = unknown but possible COX-3 OR activating the descending inhibitory path in the SC = MOST COMMON cause of liver fail in the US max dose = 4g/day
describe the body temp reflex?
afferent: Thermoreceptors in the skin, deep tissue, & SC control center: hypothalamus - preoptic region & brainstem efferent limb to cold: vasoconstriction, piloerection, shivering, nonshivering thermogenesis to hot: vasodilation diaphoresis
What is allodynia & ex? dysesthesia? neuralgia? algogenic? neuropathy? paresthesia?
allodynia = pain d/t stimulus that does not normally produce pain Ex: Fibromyalgia dysesthesia = abnormal/unpleasant sense of touch ex: burn sensation from DM neuropathy Neuralgia = pain localized to a dermatome ex: herpes zoster (shingles) algogenic= a stimulus that is normally expected to produce pain neuropathy- impaired nerve fxn paresthesia = abnorm sensation described as pins & needles
why can antidepressants be used for chronic pain? and which ones? 3
b/c pain modulation occurs in the SC -w/ central sensitization the efficacy of the descending inhibitory pathway = impaired (NE & S = inhibitory NT) - so drugs that ↑these concentrations = can tx chronic pain TCA: amitriptyline nortriptyline imipramine **Most signif s/e: QT prolong & orthostat HOTN SNRIs: venlafaxine, duloxetine, milnacipran SSRIs: fluoxetine, citlopram **SSRI + SNRI = can precipitate serotonin syndrome
beta-lacatam ex & s/e aminoglycoside ex & s/e tetracycline ex & s/e fluoroquinolone ex & s/e macrolide ex & s/e clinda s/e vanco s/e metronidazold s/e
beta-lactam: PCN, cephalosporins & ampicillin s/e: alx rxn MOST common of all abx aminoglycoside: gentamycin & streptomycin s/e: ototoxicity, nephrotoxicity, skeletal muscle weakness **CAUTION w/ NMBD tetraclycine doxycycline s/e: hepatotoxicity & nephrotoxicity fluoroquinolone: ciproflaxacin, levoflaxacin, moxifloxacin s/e: GI intolerance & tendonitis & rupture macrolide: erythromycin s/e: P450 inhibition clindamycin s/e: skeletal muscle weakness & alx rxn vancomycin s/e: rapid infusion = HOTN (histamine); red man syndrome & SJS metronidazole s/e: peripheral neuropathy & alcohol intolerance
what abx disrupts cell wall synthesis?
cepahlosporins (disrupt bacterial wall synthesis (peptidoglycan)) & Vanc VANC = drug of choice in pt w/ active MRSA
CONTACT PRECAUTIONS Transmission Prevention Organisms DROPLET PRECAUTIONS Transmission Prevention Organisms AIRBORNE PRECAUTIONS Transmission Prevention Organisms
contact -Direct contact -Gown + gloves -MRSA, VRE, Cdiff droplet - bug bigger than airborne particles -Gown + gloves + mask -Flu, RSV airborne: - bug smaller than airborne particles -Gown + gloves + N95 + neg P room -Mycobacterium tuberculosis
What causes Serotonin Syndrome? what drugs can cause SS? & 2 drug combos ↑ the risk? s/sx? & what reverses it?
d/t excess 5-HT activity in the CNS & PNS -SSRI + meperidine or fentanyl -MAOI + meperidine or ephedrine SSRIs -fluoxetine -paroxetine -sertraline -fluvoxamine -citalopram -st johns wart MAOIs -phenelzine -tranylcypromine -selegiline MISC. -meperidine -ecstasy s/sx: akathisia (inner restlessness) -agitation --> coma -tremor -clonus -muscle rigidity -mydriasis reversed w/ cyproheptadine & supportive care **Meperidine - mild anticholinergic effects, such as ↑ heart rate, dry mouth & mydriasis -d/t ATROPINE like ring -ALSO a weak serotonin reuptake inhibitor -HAS LA properties based on its chemical structure
what are the most common s/e of zofran? when should it be given?
headache &/or diarrhea given 30 min before emergence ALSO prolongs QT along w/ butyrophenones (droperidol**Black box warning))
what is the #1 cause of anesthetic mortality? mortality based on ASA status?
human error 51-77% ASA 1 = 0.04 deaths per 10,000 anesthetics ASA 2 = 0.5 deaths per 10,000 anesthetics ASA 3 = 2.7 deaths per 10,000 anesthetics ASA 4 = 5.5 deaths per 10,000 anesthetics
How is TB transmitted? what procedure has the highest rate of transmission? what does TB target? how do you DEC risk of transmission? 4 delay sx?
mycobacterium tuberculosis = bacillus that thrives in aerobic environment TARGETS ANTERIOR apical segments of lung **but can also infect brain, kidney, joints, spine & GI tract transmitted via (1-5 um) aerosolized droplets Released when person coughs, sneezes OR talks HIGHEST risk transmit w/ bronchoscopy 2nd highest = intubation DEC risk of transmission w/: -Place a high efficiency particulate air filter (HEPA) - between y-piece & pt airway -Bacterial filter = place in expiratory limb of circle circuit -DEDICATED anesthesia machine/vent = BEST -DEC risk w/ tight fitting N95 mask -pre & postop care in NEG pressure room **DELAY elective surgery UNTIL pt has antiTB chemo & has 3 NEG acid-fast bacillus test & symptom improvement
what is the problem with electrical burns?
only leave little visible damage but can have GREAT damage to viscera can cause extensive muscle damage myoglobin = nephrotoxic = needs to be flushed out of the body dysrhythmias are common
What is the seroconversion rate of HIV from a percutaneous needle injury? What is the seroconversion rate of HIV from a mucous membrane exposure?
percutaneous -0.3% mucous membrane - 0.09% MOST common occupational exposure to HIV is a needle-stick injury w/ a hollow-bore needle
what is creutzfeldt-jakob dz? from? precautions?
prion disease that can lead to encephalopathy & dementia d/t: consumption of contaminated animal protein -contaminated implants (corneal or dural tissue) -cadaveric pituitary hormone supplementation NO data to support transmission thru blood air or droplet = standard precautions
What is aqueous humor is produced by? reabsorbed by?
produced by ciliary process in the POSTERIOR chamber reabsorbed by the Canal of schlemm in the ANTERIOR chamber
which type of temp monitoring is the most accurate?
pulm artery temp = most accurate rectal = less consistent, ↑ by heat producing bacteria in the gut, ↓ by cool blood from from the LE & insulation from the stool *RISK bowel perf bladder - risk of UTI ↓ if inadequate UOP tympanic membrane = reliable but NOT for continuous b/c there is a risk of tympanic membrane injury esophageal temp = good estimation w/ minimal risk -Distal 1/3 - 1/4th of esophagus 38 - 42cm past incisors -if too deep (in stomach) = d/t heat created by the liver Nasopharynx - less reliable than esophageal & ↓ if leakage of inspiratory gas skin = NOT correlate with core
TB s/sx? dx? tx? & its s/e
s/sx: productive cough, hemoptysis, wt loss, fever, night sweats, anorexia, general malaise Dx- TB skin test (mantoux test) = most common Read w/in 48-72 hr POS = induration > 10 mm (> 5 mm if pt immunocompromised) IF pos= CXR (pos if have apical infiltrates &/or nodules) If neg CXR = rules out TB Other- acid-fast bacillus test (examines sputum) & Interferon release assay (Quantiferon TB gold test & T-SPOT TB test) Tx- isoniazid = FIRST line s/e- peripheral neuropathy & hepatotoxicity (add pyrioxidine to DEC risk of liver damage) Rifampin = causes thrombocytopenia, leukopenia, anemia & kidney failure Causes urine, sweat & tears to be RED/ORANGE OTHER first line: pyrazinamide, streptomycin & ethambutol = CAN be used to tx
Which part of the ETT is the most flammable? what tubes are flammable? what do laster resistant tubes NOT do (3)
the cuff MOST ett = flammable including ett made from polyvinyl chloride, red rubber & silicone **LASER reflective tape is NO longer advised- use a laser resistant ett instead **laser resistant tubes are NOT laser proof & do NOT have laster resistant cuff **laser resistant tubes do NOT reduce the risk of fire when electrosurgical cautery is used
problems w/ aspirin
toxicity = can cause gap metabolic acidosis ALSO (samters triad) Aspirin-exacerbated resp dz -pt can develop life-threatening bronchospasm after ASA admin triad: asthma, allergic rhinitis & nasal polyps
what is bone implantation syndrome? cause? s/sx? tx?
used to bind implants to pt bone Methyl methacrylate ↑'s intramedullary pressure in bone (up to 500 mmHg) =can cause emboli of fat, bone marrow, cement = travel to lungs s/sx: Cause v/q mismatch = ↑ dead space in extreme cases = R heart fail -residual methyl methacrylate = center systemic circulation s/e: bradycardia, dysrhythmias, HOTN (d/t ↓ SVR), pulm HTN (↑ PVR), hypoxia & cardiac arrest -hip arthroplasty = greatest risk but also w/ TKA, vertebroplasty & kyphoplasty -if regional awake = dyspnea & altered mental status -GA = ↓ etCO2 is the first s/sx tx: 100% fio2, IV hydration & neo for HoTN
what type of particles can be inhaled? what cannot?
viral transmission by inhaling smoke (s/sx: tearing, nausea & headaches) bacterial spores transmit eukaryotic cells (tumor) = NOT ransmit
What are 2 drugs that ↓ aqueous humor production what drugs facilitates aqueous humor drainage ? (causes miosis)
↓ production w/: Acetazolamide & Timolol (non selective) ↑ drainage: Echothiophate by irreversible cholinesterase inhib promotes drainage via canal of Schlemm ****BUT prolongs duration of Succ and ester LA
what things ↓ barrier pressure? ↑ barrier pressure? no effect on barrier pressure?
↓: -anticholinergics (↓ LES tone) -cricoid pressure (↓ LES tone) -preggo (↓ LES tone & ↑ intragastric pressure ↑: metoclopramide (↑LES tone) NO effect sux (↑LES tone + ↑ intragastric pressure = 0 net change)
