Bispectral index (BIS) monitoring in morbidly obese patients undergoing gastric bypass surgery: Experience in 23 patients

Background: Early and uneventful postoperative recovery of morbidly obese patients remains a challenge for anesthesiologists. BIS monitoring is useful in providing fast recovery. Methods: We describe the anesthetic management of 23 morbidly obese patients who underwent elective open Roux-en-Y gastric bypass (RYGBP) for morbid obesity. Thoracic epidural analgesia combined with light general anesthesia with propofol and nitrous oxide adjusted to keep the bispectral index (BIS) around 60 was performed. Intraoperative hemodynamic stability, early and intermediate recovery and patient satisfaction were assessed. Results: The cardiovascular variables were fairly stable during surgery. Times to spontaneous respiration, response to orders, tube removal and orientation were 4 +/- 3, 6 +/- 2, 8 +/- 3, and 13 +/- 7 respectively. Times until the patients were able to sit unassisted, stand unassisted and walk freely without assistance were 319 +/- 25, 803 +/- 78, 1070 +/- 75 respectively (values expressed as min, mean +/- sd). Conclusion: Propofol-nitrous oxide anesthesia adjusted to keep BIS around 60, combined with thoracic epidural analgesia, seems to be effective in providing predictable and uneventful recovery to patients submitted to elective RYGBP.