Aging prolongs recovery of psychomotor functions at emergence from propofol-alfentanil anaesthesia

Abstract

Purpose: To compare recovery of psychomotor function in elderly and young surgical patients at emergence from propofol-alfentanil anaesthesia. Methods: Ten elderly (> 70 yr) and 10 younger (< 40 yr) patients scheduled for orthopaedic surgery of less than three hours were anesthetized with nitrous oxide, propofol and alfentanil. Propofol and alfentanil cumulative doses, time from cessation of propofol infusion to eye opening (EO) on verbal command and to extubation were recorded. Psychomotor performance was assessed by the Mini-Mental State (MMS) performed the day prior to surgery and postoperatively at 30, 60, and 120 min. following extubation. Propofol blood concentrations were measured at EO and at each MMS task. Results: Elderly patients were comparable with young patients for preoperative MMS scores, surgery and anaesthesia duration, propofol and alfentanil cumulative doses. Postoperative MMS scores were lower at 30, 60 and 20 min. in elderly patients. Propofol blood concentrations were not different between elderly and young patients at EO, 30, 60 and 120 min. Conclusion: Psychomotor performance is impaired in elderly compared with young patients at emergence from propofol-alfentanil anaesthesia. These differences: are not likely to be related to propofol accumulation in elderly subjects.