Pharmacokinetics and pharmacodynamics of pipecuronium bromide (Arduan) in elderly surgical patients

The neuromuscular response to pipecuronium bromide (Arduan), 70 μg/kg, was studied in 20 elderly (>70 yr) and 10 younger patients (<60 yr) during nitrous oxide, fentanyl, and droperidol anesthesia. The adductor pollicis response to single 0.2-ms supramaximal pulses was recorded. Although all younger patients were completely paralyzed, 2 of 20 elderly patients did not attain 90% paralysis. Onset time in the elderly was prolonged (6.9 ± 2.6 vs 4.3 ± 1.5 min, P < 0.02). Spontaneous recovery was similar in both groups, with 75% recovery occurring at 133 ± 52 min in the elderly and 146 ± 46 min in the younger patients. The pharmacokinetic variables were similar for the two groups, and pharmacodynamic analysis revealed a similar sensitivity at the neuromuscular junction. The pharmacologic actions of pipecuronium in otherwise healthy patients do not differ between young and elderly adults.