APEX PHARM II

When does the voltage gated sodium channels assume the active state?

When threshold potential is reached (during depolarization -70 to +35)

Compared to atropine, glycopyrrolate is more likely to cause: a. tachycardia b. sedation c. mydriasis d. xerostomia

d. xerostomia (dry mouth) Makes it particularly useful for awake fiberoptic intubation as well as oral surgery. quaternary ammonium- does not cross BBB atropine is tertiary ammonium- crosses BBB- produces sedation & mydriasis; also a/w more significant tachycardia (most of all muscarinic antagonists) *atropine & scopolamine easily cross lipid membranes, including BBB, GI tract, placenta.

Compared to atropine and glycopyrrolate, scopolamine is most effective at:

preventing motion sickness, providing sedation, and drying secretions.

What is the maximum dose of EMLA cream for each age group?

0-3mos -1g 3-12mos- 2g 1-6yrs-10g 7-12yrs-20g

How much does an induction dose of succinylcholine raise serum potassium?

0.5-1.0meq/L over next 10-15min

LAs bind to what serum proteins?

1. Alpha-1-acid glycoprotein (preferred) 2. Albumin

Local anesthetics inhibit peripheral nerves(speed of onset) in the following order:

1. B fibers 2. C fibers 3. Small diameter A fibers (delta, gamma) 4. Large diameter A fibers (alpha, beta) NOTE: regression of blockade occurs in the opposite order of block onset

Rank, the nondepolarizing neuromuscular blockers in terms of potency 1=most potent, 4 least potent Cisatracurium Atracurium Rocuronium Pancuronium

1. Cisatracurium 2. Pancuronium 3. Atracurium 4. Rocuronium

Rank the speed of local anesthetic uptake after injection into each location (1 is the fastest & 4 is the slowest) Caudal Intercostal Brachial plexus Sciatic

1. Intercostal 2. Caudal. 3. Brachial plexus 4. Sciatic. The blood flow to the area where local anesthetic is injected, affects the duration of action. Therefore, it affects the concentration of LA in the blood and the risk of systemic toxicity.

What 2 patient populations have the highest risk for methemoglobin toxicity?

1. Neonates.- HgbF is relatively deficient in methemoglobin reductase, making it susceptible to oxidation. 2. Glucose-6-phosphate reductase deficiency: these patients don't possess methemoglobin reductase

List 4 drugs that reduce the incidence of shivering in the PACU:

1. Physostigmine 2. Meperidine 3. Clonidine 4. Dexmedetomidine

How is cocaine metabolized?

1. Plasma pseudocholinesterase (just like other esters) 2. Hepatic P450 enzymes (like amides)

At what plasma concentration would you expect lidocaine to produce seizures? (mcg/ml)

10-15mcg/ml Lidocaine can cause cardiac and urologic toxicity. Seizures are most likely to begin with lidocaine Cp =10-15mcg/ml

What is the dose of calcium chloride that should be administered to a child with succinylcholine induced hyperkalemia?

20 mg/kg

What is the maximum dose of Exparel?

266mg (2vials)

What is the maximum dose of EMLA cream for a 9 month old infant who weighs 8kg?

2g EMLA cream contains a 50/50 mixtures of lidocaine 2.5% and prilocaine 2.5%

All of the following statements regarding extrajunctional nicotinic receptors are true, EXCEPT: A. It's open by choline B. And epsilon subunit replaces a gamma subunit. C. It opens for a longer period of time. D. Denervation allows for its proliferation.

B. And epsilon subunit replaces a gamma subunit. The extra junctional nicotinic receptor has a gamma subunit instead of an epsilon subunit not the other way around. This structural change impacts how it responds to succinylcholine. Denervation injury, or prolonged immobility can lead to the proliferation of extrajunctional receptors

Fade during training of four stimulation is caused by: A. Agonism of presynaptic nicotinic receptors. B. Antagonism of presynaptic nicotinic receptors. C. Impaired presynaptic acetylcholine reuptake. D. Decreased acetylcholine synthesis.

B. Antagonism of presynaptic nicotinic receptors Antagonism of presynaptic nicotinic receptors produce fade during training of four stimulation. This is how nondepolarizers produce fade. Buy contrast agonism of the presynaptic nicotinic receptor prevents fade. This explains why succinylcholine does not produce fade.

The routine administration of succinylcholine is contraindicated in young children, because of the possibility of: A. Malignant hyperthermia. B. Hyperkalemic rhabdomyelosis C. Trismus. D. Bradycardia.

B. Hyperkalemic rhabdomyelosis Succinylcholine is contraindicated in young children, because of the possibility of hyperkalemic, rhabdomyolysis and patients with undiagnosed muscular dystrophy. Although the other answer choices are troubling events that can occur with the use of succinylcholine, they are not the origin of the black box warning

Which condition precludes the use of pancuronium? A. Aortic regurgitation. B. Hypertrophic cardiomyopathy C. 1stdegree AV block. D. Bradycardia.

B. Hypertrophic cardiomyopathy Pancuronium is a Vega's lytic. It increases heart rate. Depending on the patient's comorbidities, this can be helpful or harmful. The Vega's lytic affect is beneficial with aortic regurgitation in bradycardia. And the patient with hypertrophic cardiomyopathy tachycardia reduces blood flow through the left ventricular outflow tract, ultimately reducing cardiac output

Which side effect is least likely to occur after neostigmine administration? A. BRONCHOSPASM B. Mydriasis C. Nausea D. Prolonged QT interval

B. Mydriasis Neostigmine causes miosis not Mydriasis Also other PNS effects: bradycardia, bronchoconstriction, N/V/D, lacrimation, salivation, urination

Select the true statement regarding the primary mechanism of action of local anesthetics: A. The conjugate acid binds to the extracellular portion of the sodium channel. B. The conjugate acid binds to the intracellular portion of the sodium channel. C. The uncharged base mines to the extra cellular portion of the sodium channel. D. The uncharged base binds to the intracellular portion of the sodium channel.

B. The conjugate acid binds to the intracellular portion of the sodium channel. Local anesthetics are weak bases. When they are placed into solution, they dissociate into an uncharged base and its conjugate acid. You may have been tempted to select the uncharged base. This form of the drug is required for it to get an entry inside the cell. Once inside, however, its actually the conjugate acid that binds to the sodium channel.

What are the three key components of the local anesthetic molecule:

Benzene ring Intermediate side chain (determines drug class, ester/amide) Tertiary amine

Which local anesthetics are most likely to produce methemoglobinemia?

Benzocaine Cetacaine EMLA cream Methemoglobin is formed when the iron on hemoglobin molecule becomes oxidized to its ferric form (Fe3+). This decreases oxygen carrying capacity and shifts the oxyhemoglobin disassociation curve to the left.

Molecular mechanisms of opioid, receptor stimulation include, select 2: Decreased cAMP production Increase calcium conductance Increased adenylate, cyclase activity Increase potassium conductance

Decreased cAMP production Increase potassium conductance Opioid receptors are linked to G proteins, when an opioid binds to its receptor several events transpire : Adenylate cyclase activity is decreased cAMP production is decreased Calcium conductance is decreased, this reduces neurotransmitter release Potassium conductance is increased, this hyperpolarizes the nerve so it is less responsive to stimulation

Which drugs, potentiate, neuromuscular, blockade, select 3 Desflurane Gentamicin Phenytoin Mannitol Dantrolene HydroCortisone

Desflurane Gentamycin Dantrolene Duration can be prolonged by volatile anesthetics, aminoglycosides and dantrolene Duration can be shortened by phenytoin Duration is unaffected by mannitol and hydrocortisone

Acetylcholinesterase inhibitors reverse the effects of NMBs in 2 ways:

Enzyme inhibition Presynaptic effects

Identify the statement that best characterizes a phase 2 block following succinylcholine, select 2 Fade with tetany Post tetanic potentiation is absent Constant but diminished response to double burst stimulation Prolong duration

Fade with tetany Prolong, duration A phase 1 block is a normal response to succinylcholine. It is characterized by the absence of post tetanic potentiation and demonstrates a constant but diminished response to double burst stimulation. Phase 2 block occurs with an excessive dose of succinylcholine. It's characterized by fade with tetany as well as prolong duration.

What subunit is different on the nicotinic receptor with adult versus fetal?

Fetal nicotinic receptor has gamma in placement of epsilon

In the setting of symptomatic methemoglonemia, an exchange transfusion will MOST likely be required for a patient with a history of:

G6PD reductase deficiency They do not possess methemoglobin reductase ( enzyme that activates methylene blue to leucomethylene blue). Therefore, this pt population may require an exchange transfusion.

What are the pain inhibitor Neurotransmitters in the spinal neurons?

GABA & glycine

Which diseases are associated with hyperkalemia, following succinylcholine administration, select 3 Hyperkalemic, periodic paralysis Multiple sclerosis Hypokalemic, periodic paralysis Myotonic dystrophy Huntington chorea Gillian-barre

Gillian-barre Multiple sclerosis Hyperkalemic, periodic paralysis (Others include malignant hyperthermia, and upregulation of acetylcholine receptors) Impatiens with myotonic, dystrophy succinylcholine can cause muscle contractors that may interfere with ventilation intubation. There's no risk of hyperkalemia. Patience with Huntington chorea are sensitive to sux. There's no risk of hyperkalemia.

Conditions that increase sensitivity to nondepolarizing neuromuscular blockers include:

Guillian Barre ALS Huntington chorea Multiple sclerosis Myasthenia gravis Dúchenes Muscular dystrophy

Maximum doses of amide LAs

Levobupivicaine 2mg/kg Bupivicaine 2.5mg/kg Bupivicaine + Epi 3mg/kg Ropivicaine 3mg/kg Lidocaine 4.5mg/kg Lidocaine + Epi 7mg/kg Mepivacaine 7mg/kg Prilocaine 8mg/kg

LAST tx:

Manage airway Treat seizures with benzos (don't give prop) ACLS with modifications : Amiodarone is the agent of choice for ventricular dysrhythmias Avoid vasopressin, lidocaine, procainamide & Epi EPI reduces the efficacy of lipid emulsion therapy. If you must, limit dose to <1mcg/kg Administer 20% lipids Avoid beta blockers and calcium channel blockers If unresponsive to modified ACLS and lipids, prepare for CBP

Match each local anesthetic with a pKa: Chloroprocaine Mepivicaine Lidocaine Ropivacaine 7.9 8.1 7.6 8.7

Mepivicaine: 7.6 Lidocaine : 7.9 Ropivacaine : 8.1 Chloroprocaine: 8.7 The PKA, correlates with the onset of action. The closer the PKA is to the pH of the blood the faster the local anesthetic begins to take affect.

Which factors prolong the duration of succinylcholine, select 3 Metoclopramide Edrophonium Obesity Late stage pregnancy Myasthenia gravis Esmolol

Metoclopramide Late stage pregnancy Esmolol Conditions that reduce pseudocholinesterase activity can prolong the duration of succinylcholine. Some examples include metoclopramide, Esmolol, Ecothiophate, MAO inhibitors, oral contraceptives, cyclophosphamide, and neostigmine (not edrophonium) Late stage pregnancy reduces PCHE activity (other conditions that reduce PCHE activity include: atypical PCHE, severe liver disease, chronic renal failure, advanced age, malnutrition, burns, neoplasm) Obesity increases PCHE activity Myasthenia gravis is associated with resistance to succinylcholine, but this is a pharmacodynamic affect related to reduce number of nicotinic receptors at the neuromuscular junction (not PCHE activity)

What opioid agents promote histamine release?

Morphine, meperidine, codeine

What are the four types of opioid receptors? (All G proteins)

Mu (MOP) Delta (DOP) Kappa (KOP) ORL1 (NOP)

Opioids cause contraction of the sphincter of Oddi increasing biliary pressure. What can this be reversed with?

Naloxone, glucagon

Where is the best place to measure the onset of blockade and the recovery of blockade?

Orbicularis oculi; facial nerve (onset) Adductor pollicis; ulnar nerve (recovery)

Match each drug with the Primary event that terminates it's effect: Pancuronium Rocuronium Cisatracurium Atracurium Biliary excretion Renal excretion Nonspecific Ester hydrolysis Hofmann elimination

Pancuronium : renal excretion Rocuronium : biliary excretion Cisatracurium : Hoffman elimination Atracurium : non-specific Ester hydrolysis

Which phase block has the presence and/or absence of fade?

Phase 1: does NOT exhibit fade (sux) Phase 2: exhibits fade (NDNMBAs)

Which acetylcholinesterase inhibitor has a tertiary amine in its chemical structure?

Physostigmine. This allows it to penetrate the blood-brain barrier.

Which enzymes hydrolyze succinylcholine select 3 Butyrylcholinesterase Type 1 cholinesterase True cholinesterase Pseudocholinesterase Plasma cholinesterase Acetylcholinesterase

Plasma cholinesterase Acetylcholinesterase Butyrylcholinesterase

Factors that reduce the rate of vascular uptake:

Plasma protein binding (behave like reservoir) Rapid metabolism in the plasma (ester-type LA) Addition of a vasoconstrictor

Max doses of ester LAs

Procaine 7-10mg/kg Chloroprocaine 11mg/kg Chloroprocaine + Epi 14mg/kg

Sort each nondepolarizing neuromuscular blocker to its duration of action: Rocuronium Pancuronium Vecuronium Mivacurium Cisatracurium Atracurium

Rocuronium: intermediate Pancuronium: long acting Vecuronium: intermediate Mivacurium: short acting Cisatracurium: intermediate Atracurium: intermediate

Most important site of pain modulation is located where?

Substantia gelatinosa in the dorsal horn (Rexed lamina 2&3) The descending inhibitory paying pathway, begins in the periaqueductal gray (PAG) and the rostroventral medulla. It projects to the substantia gelatinosa. They release NE, serotonin, & endorphins

Which neuromuscular blockers is most likely to cause anaphylaxis?

Succinylcholine

Which NMB's release histamine?

Succinylcholine Atracurium Mivacurium Tachycardia plus vasodilation Patients who are sensitive to a higher heart rate or reduced after Lude, should not receive histamine releasing drugs, unless the clinical benefit outweighs the risk

The best qualitative bedside test of recovery from neuromuscular blockade include:

Sustained tetany greater than five seconds, sustained head lift greater than five seconds, and the patient's ability to hold a tongue blade in his mouth against force

What is a metabolite of both atracurium and Cisatracurium?

Laudanosine Atracurium produces more. As a CNS stimulant, it can produce seizures.

Which statements regarding anticholinesterase drugs are true? Select 2 50% of neostigmine is metabolized by the liver Edrophoniun and neostigmine have a synergistic affect Renal failure necessitates a second dose Neostigmine is more potent than pyridostigmine

50% of neostigmine is metabolized by the liver Neostigmine is more potent than pyridostigmine Others wrong: Mixing AchE inhibitors produces an additive (not synergistic) effect Renal failure prolongs the DOA for both AchE inhibitors & NMBs. Since both drugs remain in the body for a longer time, there's no need to adjust the dose of the AchE inhibitor to re-dose it.

What is the maximum recommended dose for lidocaine during tumescent anesthesia?

55mg/kg

Dibucaine number tells us what type of PCHE the patient produces:

70-80: typical homozygous (normal) 50-60: heterozygous variant 20-30: atypical homozygous

Which subunits MUST be occupied to open the nicotinic receptor at the motor endplate? A. Alpha & alpha B. Alpha & gamma C. Alpha & delta D. Alpha & epsilon

A. Alpha & alpha The postsynaptic nicotinic receptor is a Pentameric ligand gated ion channel located in the motor end plate at the neuromuscular junction. It's comprised of five subunits that align circumferentially around an ion conducting pore. There are two alpha subunits on this receptor, and both must be occupied by an agonist (acetylcholine or succinylcholine) for the channel open

Which local anesthetic is MOST likely to exhibit cross-sensitivity to another agent from the same class? A. Benzocaine B. Mepivicaine C. Bupivicaine D. Ropivicaine

A. Benzocaine It's an ester

Successful resuscitation of LAST is least likely following injection of which local anesthetic? A. Bupivicaine B. Ropivicaine C. Levobupivicaine D. Lidocaine

A. Bupivicaine Bupivicaine has a high affinity for the voltage-gated sodium channel and a slow rate of dissociation from this receptor during diastole. This explains why cardiac morbidity is higher with Bupivicaine & why resuscitation is so difficult

What type of bond is formed when edrophonium binds to the anionic site on acetylcholinesterase? A. Electrostatic B. Hydrogen C. Covalent D. Ester

A. Electrostatic. Acetylcholinesterase hydrolyzes acetylcholine into choline and acetate. This enzyme can be inhibited at the anionic site, and/or the esteratic site. The type of bond that is formed at these sites determines the drugs duration of action. Edrophonium forms an electrostatic bond at the anionic site and a hydrogen bond at that esteratic site. These are weak bonds, which explains its short duration of action. Neostigmine, pyridostigmine, and physostigmine form a carbamyl ester at the esteratic site. These are stronger bonds, which explains why these drugs have a longer duration of action.

What compound is implicated in allergic reactions to ester-type LA? A. Para-aminobenzoic acid B. Methylparaben C. CYP3A1 metabolites D. Psuedocholinesterase

A. Para-aminobenzoic acid (PABA)

Which characteristic correlates best with local anesthetic, duration of action? A. Protein binding B. Lipid solubility C. Pka D. Concentration

A. Protein binding. For testing purposes, you should equate : Onset of action—pKa Potency— lipid solubility Duration of action — protein binding

Key physiological effects of Mu receptor simulation include:

Analgesia, bradycardia, respiratory depression, euphoria, physical, dependence, and constipation Ligand: endorphins (beta-endorphin & emdomorphin)

How soon after lidocaine is injected can Exparel be used?

At least 20min

How soon after bupivacaine is injected can exparel be used?

At least 96 hours

Which nondepolarizing neuromuscular blockers are Benzylisoquinolinium compounds?

Atracurium Cisatracurium Mivacurium They undergo spontaneous degradation in the plasma. Hoffman elimination, and non-specific plasma esterases They are better choices for patients with hepatic or renal dysfunction .

Name for neuromuscular blockers that undergo organ-independent elimination

Atracurium Cisatracurium Mivacurium Succinylcholine

Pair an anticholinergic drug with an acetylcholinesterase inhibitor:

Atropine —Edrophonium Glycopyrrolate —neostigmine/pyridostigmne

Identify the patient at the highest risk for developing postoperative myalgia, following succinylcholine A. Six year old boy for strabismus correction B. 24-year-old female for umbilical hernia repair. C. 35 year old pregnant patient for appendectomy. D. 86 year old male for total hip arthroplasty.

B. 24-year-old female for umbilical hernia repair. Muscle pain is a side effect of succinylcholine. Young adults women more than men undergoing ambulatory surgery have the highest incidence of myalgia. While children, the elderly and pregnant patients seem to have the lowest incidence.

Cardiovascular consequences of opioid administration and healthy patients include:

Bradycardia Opioids have minimal effect on blood pressure and they don't impair the baroreceptor reflex. They also don't produce myocardial depression.

Why does succinylcholine produce bradycardia and tachycardia?

Bradycardia-stimulation of the M2 receptor in the SA node Tachycardia -mimics the action of acetylcholine at the sympathetic ganglion

Where are opioid receptors located in the following locations: Brain: Spinal cord: Peripheral:

Brain: periaqueductal gray (PAG), locus coeruleus, & rostral ventral medulla Spinal cord: primary afferent neurons in the dorsal horn & the interneurons Peripheral: sensory neurons & immune cells

Match each local anesthetic with its maximum allowable dose in the adult: Lidocaine Ropivacaine Bupivacaine Mepivicaine 300 mg 200 mg 175 mg 400 mg

Bupivacaine 175mg Ropivacaine 200mg Lidocaine 300mg Mepivicaine 400mg

Local anesthetics combine to the voltage gated sodium channels when it is in the: A. Resting and active states. B. Resting and inactive States. C. Active and inactive States. D. Active state only.

C. Active (open) and inactive (closed refractory) States. Local anesthetics preferentially bind to the alpha subunit of the sodium channel in the active and inactive states

What is the best agent to treat ventricular dysrythmias in the patient who received an intravascular injection of ropivicaine? A. Lidocaine B. Vasopressin C. Amiodarone D. Epi

C. Amiodarone Epi can hinder resuscitation from LAST, & it also reduces the effectiveness of lipid emulsion therapy. If Epi is used, it should be given in doses of <1mcg/kg Lidocaine & vasopressin should be avoided

Opioids cause nausea and vomiting by stimulating what?

Chemoreceptor trigger zone in the medulla and possible interaction with the vestibular apparatus

Which local anesthetic does not undergo protein binding?

Chloroprocaine

A patient states she experienced hypotension tachycardia and shortness of breath after receiving tetracaine during a previous surgery. Which drugs should be avoided in this patient? select 3. Benzocaine Chloroprocaine EMLA cream Articaine Cocaine Mepivacaine

Cocaine Benzocaine Chloroprocaine There are two classes of local anesthetics: esters and amides Because there's no cross sensitivity between these classes, a patient with an ester allergy may safely receive an amide and vice versa. Since the preservatives are often the cause of an alleged allergic reaction, a preservative free anesthetic should be selected.

Which factors have the MOST significant impact on the onset of action of LAs? Select 3 Concentration Dose Protein binding Lipid solubility Intrinsic vasodilation effects PKa

Concentration (secondary) Dose (secondary) PKa (most significant) Protein binding has most significant impact on DOA Lipid solubility has the most significant impact on potency but also contributes to DOA Intrinsic vasodilating effects (think enhanced uptake) impact potency & DOA

A local anesthetic with a pKa of 7.4 is expected to have a: A. Short duration of action B. Low degree of lipid solubility C. High potency D. Fast onset

D. Fast onset If the pKa of LA is closer to the pH of the blood, a larger fraction of molecules will exist as the lipid-soluble, uncharged base. In this situation, more molecules diffusing across the acólenme translates to a faster onset of action.

Administration of metoprolol to a pt exhibiting signs of cocaine intoxication is MOST likely to produce: A. Hyperkalemia B. Hypoglycemia C. Acute kidney injury D. Heart failure

D. Heart failure Beta blockade in the setting of cocaine overdose is questionable bc it allows for unopposed alpha-1 stimulation High SVR (alpha-1 stimulation caused by cocaine) & reduced inotropy (beta-1 antagonism) set the stage for CHF & CV collapse

Each additive prolongs the duration of local anesthetics, EXCEPT: A. Dexamethasone B. Dextran C. Epi D. Hyaluronidase

D. Hyaluronidase

Identify the most sensitive indicator of recovery from neuromuscular blockade: A. Nerve stimulator shows 4/4 twitches with no fade B. Tidal volume 6mL/kg C. Vital capacity >20ml/kg D. Inspiratory force better than -40cmH2O

D. Inspiratory force better than -40cmH2O Tidal volume 6mL/kg is possible, when no more than 80% of the receptors are blocked A vital capacity that exceeds 20 ml/kg as possible, when no more than 70% of the receptors are blocked 4/4 twitches without fade as possible, when no more than 70-75% of the receptors are blocked And inspiratory force better than -40cmH2O as possible, when no more than 50% of the receptors are blocked

A patient with a dibucaine number of 20 receive succinylcholine. This patient.: A. Is heterozygous for pseudocholinesterase B. Fails to produce pseudocholinesterase in sufficient quantity. C. Should receive fresh frozen plasma. D. Will be paralyzed for 8 hours.

D. Will be paralyzed for 8 hours. Atypical, PCHE is a qualitative defect. Pseudocholinesterase is produced in sufficient quantity however, the enzyme that is produced is not functional. This patient is homozygous, not hetero, for atypical PCHE, so he'll remain paralyzed for 4-8 hours Are although whole blood fresh, frozen plasma or purified human cholinesterase will restore plasma, pseudocholinesterase levels, and a patient with an atypical variant, postoperative, mechanical, ventilation, and sedation is the treatment of choice. It's the safest and least expensive option.

List 4 electrolyte disorders that potentiate neuromuscular blockade

Decrease calcium Decrease potassium Increase magnesium Increase lithium

Local anesthetics: select 2 Increase threshold potential Decrease, resting membrane potential Have no effect on threshold potential Have no effect on resting membrane potential

Have no effect on threshold potential Have no effect on resting membrane potential When a critical number of sodium channels are blocked by a local anesthetic sodium is unable to enter the neuron and sufficient quantity. This means that the neuron can't depolarize in the action potential can't be propagated. Local anesthetics do not affect resting membrane potential or threshold potential, but you should know what does : Potassium regulates, resting membrane potential Calcium regulates threshold potential

Simulation of kappa receptors produce what effects?

Helps quell shivering Dysphoria, delirium and hallucinations Ligand: Dynorphins (dynorphin A, dynorphin B, Neodynorphin)

Identify the statement that demonstrates the most accurate understanding of succinylcholine, select 2 Hypertension is a normal side effect It's an absolute contraindication with an open globe injury Severe sepsis increases the risk of hyperkalemia Masseter spasm, warrant cancellation of the plan procedure

Hypertension is a normal side effect Severe sepsis increases the risk of hyperkalemia Succinylcholine is not absolutely contraindicated with an open global entry. The risk of eye injury in this context is low and securing The airway is top priority. Massacre spasm may be a warning of sign of malignant hyperthermia. It's also a normal effect of succinylcholine. in the absence of other signs suggesting MH,the case may proceed.

How does hypocalcemia affect the threshold potential?

Hypocalcemia DECREASES TP. It makes the TP more negative. Since it moves closer to the RP, the cell is easier to depolarize.

Why does hypothermia potentiate neuromuscular blockade?

Hypothermia reduces the metabolism and clearance of neuromuscular blockers

Signs and symptoms of methemoglobinemia:

Hypoxia that isn't fixed by increasing the FiO2 Cyanosis Chocolate colored blood Tachycardia Tachypnea Change is LOC Significant concentration of methemoglobin can lead to an erroneous SPO2 reading of 85% . Tx: methylene blue 1-2 mg/kg over 5min (Max dose 7-8mg/kg)

The risk of LAST is increased in the setting of:

Hypoxia, hypercarbia, acidosis and hyperkalemia

Rate the injection sites of LA by rate of vascular uptake: (most to least vascular)

IV>tracheal>Interpleural>intercostal> caudal>epidural>brachial plexus>femoral>sciatic>subQ

Local anesthetic systemic toxicity is treated with 20% lipid emulsion, what's the dose?

Initial dose 1.5ml/kg over 2-3min Infusion: 0.25mL/kg/min If pt remains unstable, repeat bolus &/or double the infusion If >70kg: Bolus: 100ml over 2-3min Infusion: 250ml over 15-20min If pt remains unstable, repeat bolus &/or double the infusion

When does the voltage gated sodium channels assume the inactive state?

Repolarization (+35 to -70) the channel is closed during this time

What is the resting membrane potential and threshold potential in the peripheral nerve?

Resting membrane potential -70 Threshold potential -55

Name 2 NMBAs, that don't produce an active metabolite?

Rocuronium Mivacurium

Which nondepolarizing neuromuscular blockers are aminosteroid compounds:

Rocuronium Vecuronium Pancuronium

What pathologic states promote the proliferation of extra junctional receptors?

Upper or lower motor neuron injury Spinal cord injury Burns CVA Muscular dystrophy Sepsis Skeletal muscle trauma

True or false. Patients with upregulation of extrajunctional receptors are resistant to nondepolarizers.; This reduces the potency of these drugs.

True After the admin of sux, they are predisposed to hyperkalemia.