Action Duration of Atracurium in the Elderly Patients / 대한마취과학회지

ABSTRACT

BACKGROUND: The effects of a muscle relaxant may differ in elderly compared with young adult patients for a variety of the pharmacokinetic and pharmacodynamic reasons. Atracurium is eliminated by nonorgan dependent pathway, Hofmann elimination and ester hydrolysis. So there are some arguments for age-related differences. The purpose of this study was to compare the differences of the onset and duration of atracurium in young and elderly. METHODS: Eighteen young adults (21-54 yr) and 18 elderly (>65 yr) patients anesthetized with nitrous oxide and enflurane. Atracurium (0.5 mg/kg) was given and then intubation was performed after T1 response was blocked more than 80%. Neuromuscular relaxation was measured by the first twitch of train-of-four (T1) response at the adductor pollicis after supramaximal stimulation of ulnar nerve at 2Hz every 12 sec. The onset (disappearance of T1) and duration of 5, 25, 50, 75% recovery time of T1 and recovery index (time for 25-75% recovery of T1) were recorded. RESULTS: Onset of block was not significantly different between the young and elderly. Recovery time of 5, 25, 50, 75% and recovery index were not prolonged in elderly compared with young adults. CONCLUSIONS: There were no significant differences between young and elderly adults in onest time, recovery time of 5, 25, 50, 75% and recovery index when atracurium is used in a single bolus dose. The results suggest that atracurium in elderly patients has similar onset and action duration compared with younger patients.