Continuous infusions of muscle relaxants--why and how

The degree of neuromuscular blockade that occurs in an individual patient following the administration of competitive neuromuscular blocking agents cannot be accurately predicted because of the large individual variation in the pharmacokinetics and pharmacodynamics of these agents. Without monitoring of the neuromuscular blockade, this unpredictability predisposes to the occurrence of residual curarisation with its potentially lethal consequences. Variable rate continuous infusion of a short-acting competitive neuromuscular blocking agent with monitoring of the neuromuscular blockade is a flexible and accurate method for maintaining a precise degree of neuromuscular blockade during prolonged surgical procedures which ensues reliable reversability of the residual neuromuscular blockade. A system for the continuous infusion of atracurium with manual monitoring of the neuromuscular blockade is described, together with the results of a study demonstrating its efficacy.