Comparison Of The Effects Of Desflurane And Sevoflurane On Intraoperative Motor Evoked Potentials

Objective To comparethe impact Desflurane and sevoflurane on intraoperative motor evoked potentials monitoring.Methods:ASA grade 1-2,36 patients undergoing elective neurosurgery intraoperative monitoring of MEPs were randomly divided into 2 groups:group desflurane(F) and sevoflurane group(S) (n=18). Use penehyclidine hydrochloride hydrochloride 1 mg, midazolam 0.05 mg/kg, sufentanil 0.3 ug/kg, cis atracurium 1.5 mg/kg, propofol 2 mg/kg to anesthesia induction, and desflurane (group F)or sevoflurane group (S)with intravenous pumping ruifentanyl 0.1-0.3ug.kg-1.min-1 to maintain anesthesia.Intraoperative hemodynamic, bispectral index (Bispectral index, BIS), MEPs amplitude and latency, muscle relaxants (TOF value)and body temperature were monitored. When intraoperative muscle relaxant effect disappeared,stable hemodynamics,BIS40-60, temperature 36-37℃ was maintained in each group.The latency and amplitude of MEPs were recorded when the endtidal concentration of inhaled anesthetics was0.7MAC,0.8MAC,0.9MAC,1.0MAC respectively.Results:The latency of MEPs prolonged and the amplituded decressed along with the MAC increased(P<0.05).Compared with group S,the latency of MEPs was significantly longer and the amplitude was significantly lower in group F in both lower limbs of 0.7,0.8MAC(P<0.05)and in all limbs of 0.9,1.0MAC(P<0.05). But, at 0.7,0.8, MAC, two groups of both upper limbs MEPs amplitude and latency of no statistical significance(P>0.05).Conclusion:Desflurane and sevoflurane could dose-dependently inhibit MEPs monitoring, when MEPs monitoring during operation, The MAC value of desflurane and sevoflurane was best under 0.8 MAC, and the inhibitory effect of desflurane was stronger than that of sevoflurane.