Abstract: PURPOSE: To compare the effects of intravenous inhalation anesthesia and total intravenous anesthesia in facial nerve monitoring without muscle relaxant during resection of parotid tumors. METHODS: Seventy patients with parotid tumors undergoing facial nerve monitoring surgery were randomly divided into 2 groups, with 35 cases in each group. After cisatracurium administration, maintenance of anesthesia was performed by sevoflurane plus remifentanil and propofol in group sevofurane(S) and propofol plus remifentanil in group vein(V). Train-of-four ratio (TOF) was monitored and block work time, recovery time of deep blockade T₁, T₁ 50% and TOF 90% were recorded. Electrophysiological monitor was connected and the success rates of facial nerve monitoring in the recovery time of T₁ 50% were compared. The response of body movement, usage of vasoactive agents and extubation time were also recorded. SPSS 20.0 software package was used for data analysis. RESULTS: There was no significant difference in time of block work and recovery time of deep blockade between two groups(P>0.05). Recovery time of T₁ 50% and TOF 90% in group S were significantly longer than those in group V (P<0.05). All patients underwent electrophysiological monitor successfully in the recovery time of T₁ 50%. Two patients in group V had weak body movements during operation,and patients in both groups had no cardiovascular drug treatments. There was no significant difference between the two groups in time of extubation(P>0.05). CONCLUSIONS: The two methods in facial nerve monitoring without muscle relaxant during resection of parotid tumors are completely possible and effective. Sevoflurane can enhance the muscle relaxation of cisatracurium and the patients undergoing total intravenous anesthesia can receive electrophysiological signals of facial nerve earlier. Intravenous inhalation anesthesia provides lower movements.

Key words: Atracurium, Facial nerve monitoring, Intravenous inhalation anesthesia, Total intravenous anesthesia