ABSTRACT
Objective To compare the effects of total intravenous anesthesia or Intravenous-in-halation combined anesthesia on intraoperative somatosensory evoked potential (SSEP)and motor evoked potential (MEP)in spinal surgery.Methods Sixty patients scheduled for spinal surgery under general anesthesia were divided randomly and equally into 2 groups.The anesthesia was maintained with TCI propofol (plasma target concentration 3.0-3.5 μg/ml)and 1% sevoflurane+propofol in group T or group I respectively.BIS was monitored and maintained at 40-50.SSEP and MEP was re-corded before induction of anaesthesia (T0 ),5 minutes after tracheal intubation (T1 ),during skin in-cision (T2 )and at the time of decompressing spinal canal (T3 ).Results The latency of P38 and N45 prolonged,and the amplitudes of P38 and N45 was significantly depressed at T1-T3 compared to those at T0 (P <0.05).No statistically significant differences in cortical SSEP amplitudes or latency was observed in each time point.There was no case who could not detect the wave of MEP intraoperative-ly in this study.Conclusion The data from these cases indicates that 1% sevoflurane can be used in conjunction with SSEP and MEP monitoring for some adult patients undergoing spinal surgery.