Preinductive use of clonidine and ketamine improves recovery and reduces postoperative pain after bariatric surgery

Background: In obese patients, concomitant use of clonidine and ketamine might be suitable to reduce the doses and minimize the undesired side effects of anesthetic and analgesic drugs. In this study, we evaluated the perioperative effects of administration of clonidine and ketamine in morbidly obese patients undergoing weight loss surgery at a university hospital in Rome, Italy. Methods: A total of 50 morbidly obese patients undergoing open biliopancreatic diversion for weight loss surgery were enrolled. The patients were randomly allocated into a study group (n = 23) receiving a slow infusion of ketamine-clonidine before anesthesia induction and a control group (n = 27) who received standard anesthesia. The hemodynamic profile, intraoperative end-tidal sevoflurane and opioid consumption, tracheal extubation time, Aldrete score, postoperative pain assessment by visual analog scale, and analgesic requirements were recorded. Results: The patients in the study group required less end-tidal sevoflurane, lower total doses of fentanyl (3.8 ± 0.3 γ/kg actual body weight versus 5.0 ± 0.2 γ/kg actual body weight, respectively; P <.05) and had a shorter time to extubation (15.1 ± 5 min versus 28.2 ± 6 min, P <.05). The Aldrete score was significantly better in the postanesthesia care unit in the study group. The study group consumed less tramadol than did the control group (138 ± 57 mg versus 252 ± 78 mg, P <.05) and had a lower visual analog scale score postoperatively during the first 6 hours. Conclusion: The preoperative administration of low doses of ketamine and clonidine at induction appears to provide early extubation and diminished postoperative analgesic requirements in morbidly obese patients undergoing open bariatric surgery. © 2009 American Society for Metabolic and Bariatric Surgery.