Comparing intraoperative hemodynamics and medication use during cranial nerve monitoring with partial muscle relaxants versus without in cerebellopontine angle tumors: a randomized controlled trial

Abstract

Abstract Background There are many methods used for cranial nerve monitoring in cerebellopontine angle (CPA) tumor excision with or without muscle relaxant which may affect hemodynamics and consumption of drug doses. The partial neuromuscular blockade, on the other hand, appears to be compatible with monitoring in some patients, according to clinical experience. In this study, we evaluated hemodynamic changes and drug consumption differences between partial and without muscle relaxants. Forty patients ages ranging from 18 to 60 years old had CPA surgery and were given either a muscle relaxant to maintain neuromuscular blockade level train-of-four (TOF) count two (group A) or a placebo of normal saline to maintain train-of-four (TOF) count four (group B). Fentanyl was given to both groups. The dose of fentanyl was modified to 0.5–1 mcg\kg/h, while the dose of propofol was modified to have bi-spectral index between 40 and 60. The total amount of propofol and fentanyl, as well as mean blood pressure and heart rate, are all measured intraoperatively. Results There was a statistically significant difference in propofol and fentanyl doses between both research groups (p = 0.003, p = 0.002) respectively during the intraoperative period. Furthermore, there is a difference in as there were significant differences between two groups in time between stop of anesthesia and eye opening which is shorter in group with partial muscle relaxant reflecting shorter duration of anesthesia and recovery time (stop anesthesia to eye opening time) (p = 0.003, p > 0.001) respectively. Also, there was no statistically significant difference in the incidence of nausea and vomiting, shivering, bradycardia, or hypotension between the two study groups. Conclusions We demonstrated that partial muscle relaxant (train of four count 2) has benefits over no muscle relaxant (train of four count 4) for patients undergoing cerebellopontine angle tumor surgery because it can reduce anesthetic duration and generate rabid recovery. Furthermore, partial muscle relaxants exhibit the same hemodynamic stability, side effects, and surgical interruptions as group without muscle relaxants.