Anaes · Neuromuscular blockade & reversal

Neuromuscular blockade & reversal

Also known as Muscle relaxants · Neuromuscular blocking agents · Sugammadex · Train-of-four · Residual curarisation

Neuromuscular blockade is the reversible abolition of skeletal-muscle tone that makes surgery and intubation possible. The framework rests on four exam-critical ideas: the block is produced at the nicotinic receptor of the neuromuscular junction, either by depolarisation (succinylcholine) or by competitive antagonism (rocuronium, vecuronium, the benzylisoquinolines); its depth must be measured objectively with a train-of-four monitor, because the eye and the hand cannot; reversal is by two entirely different mechanisms — the acetylcholinesterase inhibitor neostigmine, which raises acetylcholine to outcompete a non-depolariser, and sugammadex, which encapsulates rocuronium and vecuronium and removes them from the junction; and the clinical goal is a train-of-four ratio of 0.9 or above at extubation, because residual blockade below that threshold causes hypoxaemia, weakness and aspiration in the recovery room. Built on the first-in-human sugammadex study (Gijsenbergh 2005), the Cochrane reviews of sugammadex and of rocuronium-versus-succinylcholine, the perioperative monitoring consensus (Naguib 2018), the SNaPP outcomes trial (Leslie 2026), the rescue-reversal trial (Lee 2009), and the perioperative hypersensitivity epidemiology (Mertes 2019).