Post-anesthesia Recovery after Infusion of Propofol with Remifentanil or Alfentanil or Fentanyl in Morbidly Obese Patients

Background: The type of opioid used during general anesthesia in the morbidly obese influences recovery and the postoperative period. In a randomized clinical trial, the postoperative recovery profile and early period after general anesthesia with remifentanil, fentanyl and alfentanil were compared in morbidly obese patients. Material and Method: 60 morbidly obese patients with BMI >35 kg/m² (mean 43.31) undergoing open Roux-en-y gastric bypass were randomly divided into 3 groups: remifentanil (R), fentanyl (F), and alfentanil (A). Dosage of opioids was based on ideal body weight (IBW): fentanyl 5 mcg/kg for intubation followed by infusion of 0.025-0.05 mcg/kg/min; alfentanil 15 mcg/kg initially, then 1.0-1.5 mcg kg/min; and remifentanil 1 mcg/kg followed by infusion of 0.25-1.5 mcg/kg/min. Anesthesia was induced with infusion of propofol and oxygen with N₂O (1:1). After anesthesia, the duration to response to verbal command, spontaneous respiration, adequate respiration, and safe extubation were recorded.The incidence of postoperative nausea and vomiting were recorded. Using verbal scale for evaluation of postoperative pain, the early postoperative analgesia requirements were assessed. Results: Demographic profiles and duration of procedure did not differ between groups. A total dose of propofol was significantly lower in Group R compared with Groups A and F (P <0.05). Duration to spontaneous respiration, adequate respiration and safe extubation were significantly shorter in Group R compared with Group F (P <0.05). Shortly after anesthesia, significantly more patients in Group R required additional dose of analgesic than in Group F (P <0.05). Postoperative nausea and vomiting (PONV) occurred significantly more often in Group R compared with Group F (P <0.05). Recovery profile of Group A was more similar to Group R, and postoperative pain and PONV evaluation more similar to Group F. Conclusion: In morbidly obese individuals, alfentanil or fentanyl and remifentanil can be safely used, but there is a higher rate of PONV and postoperative pain in the remifentanil group.