Postoperative residual curarization of rocuronium in the elderly

Objective To study the postoperative residual curarization(PORC)of rocuronium in the elderly.Methods Forty patients,with normal renal hepatic function and without muscle or nerves diseases,were divided into 2 groups of younger group(65 years old)and elder group(≥65 years old).All patients received total intravenous anesthesia with propofol,remifentainyl and rocuronium.Neuromuscular blockade was evaluated with train-of-four(TOF)stimuli of the ulnar nerve during operation.Rocuronium 0.6mg/kg was given during anesthesia induction.Postoperative neuromuscular blockade was continuously monitored until TOF rate(TOFr)reached 90%.The recovery times of TOFr from 0 to 25%,from 25% to 90%,and from the TOFr less than 90% at tracheal extubation reaching 90% were recorded.The arerial blood gas analysis was performed at the time of TOFr reaching 90%.Results The times of effect duration and the time of TOFr from 25% to 90% were(60.70±14.27)min vs.(45.51±7.80)min and(46.50±11.56)min vs.(34.50±9.56)min respectively,which were significantly longer in elder group than those in younger group(P0.05).The rate of PORC was higher in elder group than that in younger group(15/20 vs.12/20),and the duration of PORC was longer in elder group than that in younger group \[(26.00±8.43)min vs.(17.20±8.00)min\](P0.05).The number of CO2 accumulation after extubation in elder group was more than that in younger group(13 vs.6)(P0.05).Conclusion The elder patients are at a high risk of PORC and attention should be paid to the evaluation of the neuromuscular blockade and of the proper time of tracheal extubation.