Impact of opioid free anesthesia on glycemia: a randomized controlled trial

Abstract

Background: General anesthesia induces frequently hyperglycemia. This is associated with an increased risk of morbidity and mortality in patients undergoing surgery. The type of anesthesia used may affect the severity of the peri-operative hyperglycemia.

Methods: Patients undergoing an elective primary laparoscopic bariatric surgery at AZ Sint-Jan Brugge between February 2022 and March 2022 were randomized between opioid-free anesthesia (OFA) and opioid anesthesia (OA) after ethical approval. Any patient with diabetes type 1, diabetes type 2, having glucose intolerance at the time of surgery, or during pregnancy were excluded from the study. Dexmedetomidine, lidocaine, ketamine, and magnesium were used for the OFA, while sufentanil was given in the OA. No intravenously steroids were administered to protect the peritoneum nor as antiemetic prophylaxis. The increase in blood glucose level at 180’ was assessed as the primary outcome. A first measurement was taken just before the anesthesia induction (T0), followed by a measurement every hour (T60’, T120’, and T180’). As secondary endpoints, the total dose of opioids given in the first 24 hours and the postoperative pain using the VAS (visual analog scale) score were measured. Additionally, postoperative nausea and vomiting (PONV), duration of surgery, and surgical and/or anesthetic complications were recorded.

Results: A total of 43 patients underwent an elective primary laparoscopic bariatric surgery. 22 patients received OFA and 20 patients received OA and were analyzed. One patient from the OA group withdrew written consent. 2 patients from the OFA group were lost to follow up having therefore 19 in the OA and 20 in the OFA for analysis. There were no significant differences between the two groups regarding age, BMI, gender, duration of surgery, and pre-induction glycemia. The glycemia level increased in both groups but increased significantly higher in the OA group at 180 minutes (Mann-Whitney test p = 0.027). OFA was associated with lower VAS scores postoperative (OFA: 3(2-4) vs OA: 4(4-5,5)) and a reduced need for postoperative opioids (OFA: 4.9(2,4-7,2) mg versus OA: 10,4(8,4-12,7) mg).

Conclusion: This research suggest that the use of opioid-free anesthesia causes a smaller increase in glycemia during elective laparoscopic bariatric surgery compared to opioid anesthesia. Furthermore, patients undergoing OFA showed higher levels of postoperative comfort, demonstrated through the lower postoperative VAS scores and the reduced need for postoperative opioids.