Anesthesia With Propofol Does Not Reduce Interleukin-6 Release in Response to Abdominal Surgery of Varying Severity

Background: Data on whether anesthesia with propofol promotes or attenuates interleukin-6 (IL-6) production are conflicting. The purpose of this study was to investigate the effect of different doses of propofol, but similar doses of opiates, on plasma concentrations of IL-6 in patients undergoing two distinct operations of different severity and duration. Methods: This study was a prospective, single-center, two-armed observational study. Blood samples were collected in 28 patients undergoing abdominal hysterectomy (H) or vulvectomy (V). IL-6 was measured 24 hours preoperatively, prior to induction, at the end of the operation, and at 24 and 96 hours postoperatively. We tested the effect of propofol on IL-6 levels with linear regression. Results: IL-6 concentrations at the end of surgery were significantly higher in group H than in group V (38.6 (31.3) pg/mL vs. 3.7 (2.7) pg/mL, P < 0.001). Peak levels of IL-6 were seen in group H at the end of operation, while maximum levels in group V were attained 24 hours after surgery. No relationship between administered amount of propofol and IL-6 release could be identified. However, peak levels of IL-6 were significantly correlated to surgery duration in both group H and group V (r = 0.773, P = 0.002 vs. r = 0.568, P = 0.034). Conclusions: Propofol does not diminish perioperative levels of IL-6 in patients undergoing abdominal hysterectomy or vulvectomy. The results also suggest that surgery duration is the main determinant of IL-6 response in both patient groups. Our findings indicate that there may be a clinical benefit to reduce the duration of surgery.