Clinical Observation Of Cisatracurium Dosage In Subtentorial Tumor Resection Using Intraoperative Neurophysiological Monitoring

Objective:This study aims to find the appropriate dosage of cisatracurium which combining with low concentration of sevoflurane and propofol as well as remifentanil through continuous intravenous infusion when undergoing subtentorial tumor resection using intraoperative neurophy-siological monitoring（IONM）.Methods:Under the same background of intravenous-inhalation combined anesthesia,sixty patients who underwent subtentorial tumor resection were selected,the patients were randomly divided into 3 groups according to the intraoperative continuous infusion dosage of cisatracurium;during the maintenance of intraoperative anesthesia group S₀ was not used cisatracurium;group S₁ was given 1 times ED₉₅ cisatracurium through continuous infusion at a rate of 0.05mg/（kg·h）;group S₂ was given 2times ED₉₅ cisatracurium through continuous infusion at a rate of0.1mg/（kg·h）.Narcotrend was used to monitor the depth of anesthesia,the Narcotrend index was maintained between 40 and 60 under the condition of adjusting the dosage of propofol and remifentanil.Muscle relaxant levels were monitored using Train of four（TOF）,brainstem auditory evoked potential（BAEP）and upper and lower limbs somatosensory evoked potential（SEP）,motor evoked potential（MEP）as well as electromyography（EMG）were monitored.The mean blood pressure（MBP）,heart rate（HR）and Narcotrend index of the patients were recorded at the time of pre-operation（T₀）,open skull flap（T₁）,intraoperative tumor resection（T₂）,and postoperative extubation（T₃）.The baseline of IONM were established 30min after anesthesia induction,the latency and amplitude of BAEP,SEP and MEP during and after tumor resection,as well as the EMG and the corresponding TOF value were also recorded.Result:During the procedure（T₂）the HR and MBP of group S₀ were significantly lower than that in group S₁ and group S₂（P<0.05）;The dosage of propofol and remifentanil in group S₀ was significantly higher than that in group S₁ and S_2,while the dosage of cisatracurium was significantly lower（P<0.05）;Extubation time in group S₂ was longer than that in group S₀（P<0.05）;Significant MEP waves could be detected in both group S₀ and group S₁ and the corresponding TOF count was greater than or equal to 2;In the group S₂ there were 5 patients can get significant MEP waves and the corresponding TOF count was 2 while another 15 patients can not get significant MEP waves and the corresponding TOF count was 1.There was a significant difference between the latency and amplitude of MEP when the TOF count was 2than that when the TOF count was 4（P<0.05）.There was no significant difference in SEP and BAEP latency and amplitude between the three groups（P>0.05）.When the TOF count was greater than or equal to 2,the patients could get significant EMG signal.When TOF count was 1,EMG wave was not induced.Conclusion:The group S₁ that continuous infusion of 1 times ED₉₅ cisatracurium at the rate of 0.05mg/（kg·h）could not only meet the requirements of surgical operation and IONM,but also be convenient to anesthesia management.