Intraoperative epidural analgesia prevents the early proinflammatory response to surgical trauma. Results from a prospective randomized clinical trial of intraoperative epidural versus general analgesia

Background: The intraoperative epidural analgesia (EA) has the potential to reduce stress response to surgical trauma which induces a transient immunoactivation that has a negative impact on the outcome. This study investigates the effect of intraoperative EA versus intravenous analgesia (IA) on the immune function. Methods: A total of 35 consecutive patients candidated to undergo major surgery for colon cancer were randomly assigned to intraoperative EA (n = 18) or IA (n = 17). Blood samples for TNF-α, IFN-γ, IL-1, IL-2, IL-4, IL-6, IL-10, IL-12, and GM-CSF were obtained before surgery (T _pre), 3 h (T _3h), and 24 h (T _24h) after skin incision. Data on postoperative complications were prospectively collected and analyzed. Results: In the EA group, IL-4 increased from T _pre to T _3h and from T _3h to T _24h, IL-10 increased from T _pre to T _3h and persisted unmodified thereafter. At all time-points, IL-4 and IL-10 serum levels were significantly higher than those in the IA group. Conversely, in the IA group, IL-4 and IL-10 serum levels did not change while all other cytokines levels were significantly higher compared with the EA group. In particular, IL-6 progressively reached a 7-fold increase of its basal value at T _24h. Complications were significantly more common in IA patients (13 of 17) compared with EA patients (7 of 18) (P = .024). Conclusions: Our results indicate that in cancer patients undergoing major elective colon surgery, the EA attenuates the surgery-induced proinflammatory response and the typical postoperative transient immunosuppression and seems associated with a reduced rate of postoperative complications compared with IA.