Neuromuscular blocking agents are commonly used to facilitate endotracheal intubation. Succinylcholine, a short-acting, depolarizing neuromuscular blocking agent, is the most commonly used agent for paralysis in this setting because of its rapid onset and short duration of paralysis. In patients with contraindications to succinylcholine or in whom a difficult airway is anticipated, a neuromuscular blocking agent with a pharmacodynamic profile similar to succinylcholine would be an attractive alternative. Rocuronium, a new intermediate-acting nondepolarizing neuromuscular blocking agent produces paralysis within 60 seconds, similar to succinylcholine, but has a duration of paralysis of approximately 20 to 30 minutes. If rocuronium-induced paralysis could be chemically reversed within 10 to 15 minutes after the administration of an intubating dose, it may be an appropriate alternative in patients with contraindications to succinylcholine or in patients in whom a difficult airway is anticipated. Neostigmine is an anticholinesterase agent that inhibits the hydrolysis of acetylcholine by competing with acetylcholine for attachment to acetylcholinesterase. Inhibition of the breakdown of acetylcholine allows the neurotransmitter to be present in the neuromuscular junction for a longer period of time, so that each molecule can bind repeatedly with the acetylcholine receptor. The purpose of this study is to determine the dose of neostigmine necessary for the early reversal of rocuronium-induced paralysis.
