Effects of positioning in laparoscopic adnexal surgery on QT dispersion and heart rate variability under sevoflurane anesthesia

PURPOSE: This study compared the intraoperative changes in the corrected QT dispersion and heart rate variability, predictors of autonomic cardiac function, in laparotomic and laparoscopic adnexal surgery. MATERIALS AND METHODS: The study was conducted on 46 American Society of Anaesthesiologists class I/II patients, aged 33-51 years, randomized to one of two groups, for elective gynecologic laparotomy or laparoscopy for a benign adnexal mass. Anesthesia was induced and maintained with sevoflurane. Corrected QT dispersion and spectral powers of heart rate variability were measured at baseline, before the induction of anesthesia, and intraoperatively during the adnexal surgery for 15 minutes. The lithotomy and Trendelenburg positions were set at 145 degrees and 30 degrees between thigh and body, respectively. Pneunoperitoneum was established at 12 mm Hg. Laparoscopic surgery was performed via one principal and two ancillary ports. Data were analyzed using the Wilcoxon and Mann-Whitney tests. RESULTS: A significant increase was observed in intraoperative standard deviation of RR interval values of heart rate variability in both groups compared to preoperative values (P < 0.05). The corrected QT dispersion and low and high frequency heart rate variability showed no significant changes between the two groups. CONCLUSION: Gynecologic laparoscopy with pneumoperitoneum in the lithotomy and Trendelenburg positions is as safe as laparatomy and seems not to deteriorate the autonomic cardiac function.