Influences of cisatracurium besylate and vecuronium bromide on muscle relaxant effects and electromyography of tracheal intubation under general anesthesia.

OBJECTIVE: To observe the influences of atracurium besylate and vecuronium bromide on muscle relaxant effects and electromyography of patients with tracheal intubation under general anesthesia in thyroid surgery. PATIENTS AND METHODS: 120 patients treated with thyroid surgery were randomly divided into group A and group V. Patients in group A were administered with cisatracurium besylate combined with propofol and fentanyl for induction of tracheal intubation under general anesthesia. Patients in group V were administered with 0.10 mg/kg vecuronium bromide combined with propofol and fentanyl for induction of tracheal intubation under general anesthesia. Then, the amplitude in electromyography was observed 30-70 min after I.V. muscle relaxant medicine to record the time for patients to reach 0% TW convulsion in abductor pollicis muscle and to observe the muscle relaxant effects. RESULTS: There was no statistical difference in the time to reach 0% TW in two groups (p>0.05). After 30 min of injection of muscle relaxants, EMG positive rate and TW value in group A were significantly higher than those in group V (p<0.05). After 50-70 min of injection of muscle relaxants, EMG positive rate of patients in two groups was up to 100%, and EMG amplitude in group A was significantly higher than that in group V (p<0.05). The time of taking muscle relaxant effects in group A was significantly faster than that in group V (p<0.05), while the recovery time of autonomous respiration and the time of autonomous body activity in group A were slightly lower than those in group V (p>0.05). There was no statistical difference in the time of eye-opening of both groups (p>0.05). MAP and HR of patients in both groups showed no statistical difference before and after injection (p>0.05). CONCLUSIONS: Average EMG amplitude and the positive rate of effective EMG amplitude of cisatracurium besylate are all higher than those of vecuronium bromide. With faster effects and shorter action time, cisatracurium besylate is more suitable in thyroid surgery IONM (intraoperative neurophysiological monitoring).