Effects Of Rocuronium And Sevoflurane Respectively On Evoked Electromyographic Monitoring Of Facial Nerve

Part1The Effects of rocuronium-induced different degree of neuromuscular blockade on evoked electromyographic monitoring of facial nerveObjective:To evaluate the effects of rocuronium-induced different degree of neuromuscular blockade (NMB) on evoked electromyographic (EEMG) monitoring of facial nerve.Methods:Thirty-five ASA Ⅰ-Ⅱ patients of both sexes, aged20-64years, body mass index (BMI)≤30kg/m,scheduled for elective neurosurgical operation were studied. Patients with abnormal facial nerve function or neuromuscular disease were excluded. Anesthesia was induced intravenously with midazolam0.05-0.1mg/kgs fentanyl3-5ug/kg and propofol1.5-2.5mg/kg, after the patient was anesthetized, facial nerve EEMG and NMB monitoring were performed simultaneously. Stimulating the facial nerve and recording the amplitude and latency as control value. Then given rocuronium0.6mg/kg, the facial nerve EEMG amplitude and latency were measured when the degree of NMB was at100%、75%、50%and25%. The changes of amplitude were expressed as amplitude reservation ratio because the amplitude of EEMG were so different in each person. Amplitude reservation ratio is equal to amplitude of different levels of NMB division the amplitude before given rocuronium. Evaluating the relationship between the amplitude reservation ratio, latency respectively and NMB levels.Results:Six out of thirty-five patients had no EEMG response at the degree of NMB100%, while all of the patients had detectable EEMG responses at the levels of NMB≤75%. There was a negative correlation between the amplitude reservation ratio and the levels of NMB, correlation coefficient was0.947, coefficient of determination was0.898, linear regression equation was expressed as:Y=1-0.787X;while a positive correlation between latency and NMB levels, correlation coefficient was0.328.There had conspicuous statistics different between amplitude reservation ratio under different levels of NMB (P<0.05), while the latency of NMB50%,75%and100%were different with the control value (P<0.05).Conclusion:1With the level of NMB diminished, the amplitude reservation ratio of facial nerve EEMG increased gradually, while the latency decreased gradually.2Compare with the latency, the amplitude reservation ratio was more susceptible to the partial neuromuscular blockade technique Part2The effects of different concentration and different time of sevoflurane inhalation on evoked electromyographic monitoring of facial nerveObjective:To observe the effects of different concentration and different time of sevoflurane inhalation on evoked electromyographic monitoring of facial nerve.Methods:Thirty ASA Ⅰ-Ⅱ patients of both sexes, aged20-64years, body mass index (BMI)<30kg/m2,scheduled for elective neurosurgical operation were studied. Patients with abnormal facial nerve function neuromuscular disease or intracranial hypertension were excluded.Patients in our study were randomly divided into two groups, one group was given1MAC sevoflurane(Ⅰ group) and the other was given1.3MAC sevflurane (Ⅱ group). Stimulate the facial nerve before inhalation (T0) and at the time of15min(T1)、30min(T2)、45min(T3)、60min(T4) after expire end concentration of sevoflurane reached the preset goal, then measured and recorded the amplitude and latency. The changes of amplitude were expressed as amplitude reservation ratio. Evaluating the relationship between the amplitude reservation ratio, latency respectively and sevoflurane.Results:The two group’s amplitude reservation ratio and latency were different at any points of time before and after sevoflurane inhalation. Compare with TO, the amplitude reservation ratio of two groups were decreased significantly at T2and T1respectively, at T4both of them reached the minimum value:94.29%vs85.11%; The two group’s latency were extended at T4and T3respectively, changes no more than4%. Although the Ⅱ group’s amplitude reservation ratio were smaller than the Ⅰ group’s at any points of time after sevoflurane inhalation, the latency of two groups were no significantly different.Conclusion:1With the increasing of concentration and time of sevoflurane inhalation, the amplitude reservation ratio of facial nerve EEMG decreased gradually, while the latency did not extend obviously2Although inhaling1-1.3MAC sevoflurane60min could affect the evoked electromyographic monitoring of facial nerve to a certain extent, the facial nerve monitoring could still be carried out successfully.