A multicenter, randomized, controlled study evaluating preventive etanercept on postoperative pain after inguinal...

Chronic postsurgical pain (CPSP) affects between 5% and 70% of surgical patients, depending on the surgery. There is no reliable treatment for CPSP, which has led to an increased emphasis on prevention. In this study, we sought to determine whether preventive etanercept can decrease the magnitude of postoperative pain and reduce the incidence of CPSP.

We performed a multicenter, randomized study in 77 patients comparing subcutaneous etanercept 50 mg administered 90 minutes before inguinal hernia surgery with saline. Patients, surgeons, anesthesiologists, the injecting physician, nursing staff, and evaluators were blinded. The primary outcome measure was a 24-hour numerical rating scale pain score. Secondary outcome measures were postanesthesia care unit pain scores, 24-hour opioid requirements, time to first analgesic, and pain scores recorded at 1 month, 3 months, 6 months, and 12 months.

Mean 24-hour pain scores were 3.3 (95% confidence interval [CI], 3.2-4.6) in the etanercept and 3.9 (95% CI, 2.6-4.0) in the control group (P=0.22). The mean number of analgesic pills used in the first 24 hours was 4.0 (SD, 2.8) in the treatment versus 5.8 (SD, 4.2) in the control group (P=0.03). At 1 month, 10 patients (29%) in the treatment group reported pain versus 21 (49%) control patients (P=0.08). The presence of pain at 1 month was significantly associated with pain at 3 months (hazard ratio, 0.74; 99% CI, 0.52-0.97; P=0.03).

Although preventive etanercept was superior to saline in reducing postoperative pain on some measures, the effect sizes were small, transient, and not statistically significant. Different dosing regimens in a larger population should be explored in future studies.