NBCRNA Pharmacology for Nurse Anesthetists 2 — Questions and Answers
Question 1: Which local anesthetic is most associated with cardiac toxicity due to its high protein binding and sodium channel blocking properties?
- Bupivacaine (Correct answer)
- Lidocaine
- Chloroprocaine
- Mepivacaine
Correct answer: Bupivacaine
Bupivacaine has a high affinity for cardiac sodium channels and dissociates very slowly, making cardiotoxicity severe and difficult to treat.
Question 2: What is the reversal agent for benzodiazepine-induced sedation?
- Flumazenil (Correct answer)
- Naloxone
- Neostigmine
- Physostigmine
Correct answer: Flumazenil
Flumazenil is a competitive benzodiazepine receptor antagonist that reverses sedation, amnesia, and respiratory depression caused by benzodiazepines.
Question 3: Dexmedetomidine produces sedation and analgesia primarily through which mechanism?
- Alpha-2 adrenergic receptor agonism (Correct answer)
- GABA-A receptor potentiation
- Opioid receptor activation
- Muscarinic receptor antagonism
Correct answer: Alpha-2 adrenergic receptor agonism
Dexmedetomidine acts on alpha-2 adrenergic receptors in the locus coeruleus and spinal cord to produce sedation, anxiolysis, and analgesia without respiratory depression.
Question 4: Which volatile anesthetic is contraindicated in patients at risk for malignant hyperthermia?
- All potent volatile agents (Correct answer)
- Nitrous oxide only
- Propofol
- Ketamine
Correct answer: All potent volatile agents
All potent volatile anesthetic agents (halothane, isoflurane, desflurane, sevoflurane) are known triggers for malignant hyperthermia in susceptible individuals.
Question 5: What is the primary mechanism by which neostigmine reverses non-depolarizing neuromuscular blockade?
- Acetylcholinesterase inhibition (Correct answer)
- Direct NMDA receptor activation
- Competitive displacement of NMB agent
- Sugammadex encapsulation
Correct answer: Acetylcholinesterase inhibition
Neostigmine inhibits acetylcholinesterase, increasing the concentration of acetylcholine at the neuromuscular junction to competitively overcome the non-depolarizing blockade.
Question 6: Succinylcholine is contraindicated in patients with burn injuries because it can cause life-threatening what?
- Hyperkalemia (Correct answer)
- Hypokalemia
- Malignant hyperthermia
- Bradycardia
Correct answer: Hyperkalemia
Burn, crush, and denervation injuries cause upregulation of extrajunctional acetylcholine receptors, and succinylcholine-induced depolarization can release lethal amounts of potassium.
NBCRNA Pharmacology for Nurse Anesthetists 2
Which local anesthetic is most associated with cardiac toxicity due to its high protein binding and sodium channel blocking properties?