Question Set #4: NMJ blockers

Anesthesia Pharmacology Chapter 18: Neuromuscular Blocking Drug Practice Questions

Extent of nicotinic receptor blockade required for neuromuscular transmission failure due to nondepolarizing neuromuscular blockers:
1. < 5%
2. about 20%
3. about 50%
4. > 80%-90%
Factor(s) responsible for cardiovascular effects of nondepolarizing neuromuscular blockers:
1. histamine release
2. effects mediated by autonomic nicotinic, cholinergic receptors
3. effects mediated by cardiac muscarinic, cholinergic receptors
4. A & C
5. A, B & C
Difference(s) in cardiovascular responses (patient to patient) to nondepolarizing neuromuscular blockers include(s):
1. preoperative medications
2. basal autonomic state
3. which drug is used for anesthetic maintenance
4. the presence of other drugs
5. all of the above
Definition of "autonomic margin of safety":(for nondepolarizing neuromuscular blockers)
1. difference between dosage producing neuromuscular-blockade and dosage producing cholinergic blockade
2. the degree to which the autonomic nervous system must be activated to cause hypertension
3. the extent to which the autonomic nervous system must be inhibited to cause neuromuscular blockade safely
4. the difference between neuromuscular-blocking dosage which produces neuromuscular blockade and the doses producing circulatory effects
5. all of the above
Relatively low autonomic margin of safety:
1. roncuronium (Zemuron)
2. cisatracurium (Nimbex)
3. pancuronium (Pavulon)
4. vecuronium (Norcuron)
5. all the above have low autonomic margins of safety
Patients on nondepolarizing neuromuscular blockers (to facilitate mechanical ventilation during prolonged illness) may to skeletal muscle weakness following recovery. Characteristic(s) include(s):
1. moderate to severe quadriparesis
2. weakness duration always less than 2 days
3. more common with aminosteroid agents
4. B & C
5. A & C
Myopathy associated with critical illness (following long-term nondepolarizing agent mediated neuromuscular-blockade):
1. more common with vecuronium (Norcuron)
2. more common with atracurium (Tracrium)
Least likely to influence magnitude or duration of neuromuscular-blockade (caused by nondepolarizing agents):
1. halothane (Fluothane)
2. isoflurane (Forane)
3. nitrous oxide-opioid combinations
4. desflurane (Suprane)
5. sevoflurane (Sevorane, Ultane)
Prominent interactions of volatile anesthetics with nondepolarizing, neuromuscular-blocking drugs:
1. isoflurane (Forane)
2. desflurane (Suprane)
3. sevoflurane (Sevorane, Ultane)
4. A & C
5. A, B & C
Most likely to require greater reduction in blocker dosage as a result of volatile anesthetic use:
1. atracurium (Tracrium)
2. roncuronium (Zemuron)
3. doxacurium (Nuromax)
4. cisatracurium (Nimbex)
5. vecuronium (Norcuron)
Intermediate-duration agent (category of nondepolarizing neuromuscular-blocking drug):
1. pancuronium (Pavulon)
2. pipecuronium (Arduan)
3. cisatracurium (Nimbex)
4. doxacurium (Nuromax)
5. succinylcholine (Anectine)
Antibiotic most likely to have an effect on neuromuscular-blockade due to nondepolarizing agents:
1. chloramphenicol (Chloromycetin)
2. clarithromycin (Biaxin)
3. azithromycin (Zythromax)
4. tobramycin (Nebcin)
5. penicillin V (Pen-Vee K, Veetids)
Antibiotics most likely to produce increased neuromuscular-blockade in the presence of nondepolarizing blockers:
1. amikacin (Amikin)
2. gentamicin (Garamycin)
3. spectinomycin (Trobicin)
4. kanamycin (Kantrex)
5. all of the above
Antiarrhythmic drug(s) which may increase preexisting neuromuscular-blockade due to nondepolarizing agents:
1. lidocaine (Xylocaine)
2. quinidine gluconate (Quinaglute, Quinalan)
3. both
4. neither
Electrolyte change, due to chronic diuretic use, which decreases pancuronium (Pavulon) dose requirements:
1. hypokalemia
2. hyperkalemia
Magnesium and neuromuscular-blockade:
1. reduction neuromuscular-blockade (nondepolarizing) when magnesium is administered to patients to manage pregnancy-caused hypertension (toxemia of pregnancy)
2. interaction probably more pronounced with magnesium and vecuronium (Norcuron)
3. accentuates blockade by nondepolarizing agents, not by depolarizing drugs (e.g. succinylcholine (Anectine))
4. all of the above
Main use for streptomycin:
1. management of plague
2. management of tularemia
3. management of brucellosis
4. second line treatment for tuberculosis
5. treatment for viridans streptococcal endocarditis
Clinical context:initial administration of succinylcholine (Anectine, 1 mg/kg, IV); subsequent administration of nondepolarizing agent
1. nondepolarizing agents (e.g. atracurium (Tracrium) or vecuronium (Norcuron)) -- increased initial response
2. Duration of action of nondepolarizing agents (atracurium (Tracrium) or vecuronium (Norcuron)): not affected
3. both
4. neither
Drug combinations and effects on neuromuscular-blockade:
1. pancuronium (Pavulon) and + metocurine (Metubine Iodide): enhancement of blockade
2. vecuronium (Norcuron) + tubocurarine: enhancement of blockade
3. both
4. neither
Combinations of nondepolarizing agents to achieve same degree of blockade: advantageous
1. true
2. false