A 43-year-old man presents to his primary care physician to discuss medical clearance for an elective knee arthroplasty. The patient is concerned because when he underwent cholecystectomy the previous year he experienced a complication as a result of the anesthesia that was used. Upon chart review, it appears that the patient experienced severe hyperkalemia and hyperthermia.
Which of the following agents was most likely used during this patient's surgery?
D) Succinylcholine
Succinylcholine is a depolarizing neuromuscular blocking agent that directly activates the acetylcholine receptors at the neuromuscular junction. Malignant hyperthermia is a possible side effect, and hyperkalemia may result from depolarization. Succinylcholine should not be used in patients with an acetylcholinesterase deficiency, as these patients experience prolonged neuromuscular blockade.
Answer choice A: Atropine, is incorrect. Atropine is an antimuscarinic agent. It can be administered with acetylcholinesterase inhibitors such as neostigmine to prevent off-target muscarinic effects.
Answer choice B: Neostigmine, is incorrect. Neostigmine is an acetylcholinesterase inhibitor which can be used as a reversal agent for nondepolarizing neuromuscular blocking agents. It works by increasing the acetylcholine concentration at the neuromuscular junction such that acetylcholine can outcompete the blocking agent, thus restoring normal neuromuscular function.
Answer choice C: Rocuronium, is incorrect. Rocuronium is a nondepolarizing neuromuscular blocking agent that competitively inhibits the nicotinic acetylcholine receptors at the motor end plate. Vecuronium is a similar agent which has decreased lipophilicity, slower onset, and increased potency compared to rocuronium.
Answer choice E: Sugammadex, is incorrect. Sugammadex is a modified gamma-cyclodextrin designed to encapsulate rocuronium. It can also be used for reversal and does not require the addition of an antimuscarinic agent for symptom management due to its unique mechanism of action.
Key Learning Point
Succinylcholine is a depolarizing neuromuscular blocking agent. Possible adverse effects include malignant hyperthermia and hyperkalemia.
