Which reversal agent is most likely to cause postoperative bradycardia due to prolonged acetylcholine elevation?

Which reversal agent is most likely to cause postoperative bradycardia due to prolonged acetylcholine elevation?

• A. Neostigmine
• B. Edrophonium
• C. Pyridostigmine
• D. Sugammadex

Answer: (C)

Muscarinic effects on the heart drive bradycardia when acetylcholine levels rise. Reversing a nondepolarizing block with cholinesterase inhibitors increases acetylcholine at both the NMJ and muscarinic receptors. Among the options, the one with the longest duration of action causes acetylcholine to stay elevated longer, increasing the risk of postoperative bradycardia unless antimuscarinic agents are used. Pyridostigmine is the longest-acting among these reversal agents, so it’s most likely to cause prolonged acetylcholine elevation and bradycardia. Sugammadex reverses blockade without increasing acetylcholine and thus avoids this muscarinic bradycardia risk.

Muscarinic effects on the heart drive bradycardia when acetylcholine levels rise. Reversing a nondepolarizing block with cholinesterase inhibitors increases acetylcholine at both the NMJ and muscarinic receptors. Among the options, the one with the longest duration of action causes acetylcholine to stay elevated longer, increasing the risk of postoperative bradycardia unless antimuscarinic agents are used. Pyridostigmine is the longest-acting among these reversal agents, so it’s most likely to cause prolonged acetylcholine elevation and bradycardia. Sugammadex reverses blockade without increasing acetylcholine and thus avoids this muscarinic bradycardia risk.