Figure 55-4 Disappearance of vecuronium from plasma after a single bolus dose of 0.2 mg/kg. A semilogarithmic plot of plasma concentration versus time shows that the vecuronium concentration remained at a much higher level during the elimination phase in patients with cirrhosis (open circles) than in normal control patients (black circles). This difference reflects the markedly decreased plasma clearance of vecuronium, increased elimination half-life, and increased duration of neuromuscular blockade in patients with cirrhosis versus normal individuals. (From Lebrault C, Berger JL, D'Hollander AA, et al: Pharmacokinetics and pharmacodynamics of vecuronium (ORG NC 45) in patients with cirrhosis. Anesthesiology 62:601–605, 1985.)