A Prospective, double-blinded randomized controlled study comparing two different Trendelenburg tilts in laparoscopically assisted vaginal hysterectomy positioning.

BackgroundBispectral index (BIS) used for intra-operative depth assessment under general anesthesia (GA) can be altered by different factors. This study was designed to detect the alteration in BIS reading with two different Trendelenburg (TBG) tilt in laparoscopically assisted vaginal hysterectomy (LAVH) procedure.Materials and methodsA prospective, double-blinded, randomized controlled study was designed involving 40 American Society of Anesthesiologists Grade I and II female patients, aged 35-60 years, scheduled to undergo LAVH under GA. Patients were divided into two groups with TBG >30° and TBG 30°) or (<30°) as per group allotment. Data were recorded at 30 min intervals and all the patients were followed upto 24 h postoperatively for any recall.ResultsA rise in BIS value was noticed, when position was changed from supine to head down in both groups. During comparison between two groups with different angulations, TBG >30° showed a higher BIS value than TBG <30°. This statistically significant (P < 0.05) trend was observed at all the 30, 60, 90, and 120(th) min interval. Interestingly, BIS values returned to preoperative levels following adopting final supine position. No incidence of awareness was reported in both the series throughout the study.ConclusionThough awareness remains unaltered BIS value gets increased with higher angle of inclination in TBG position during LAVH operation.