Objective: The aim of the current study was to evaluate the safety and efficacy of a widely available bupivacaine continuous wound infusion system in gynecologic oncology patients undergoing laparotomy.
Methods: A prospective, randomized, double-blind, placebo-controlled trial was performed. After closure of the fascia, flexible soaker catheters were placed in the deep subcutaneous space. The infusion pump was filled with 290 mL of either 0.5% bupivacaine or normal saline, to infuse over 72 hours. Daily assessments of pain scores utilized the Wisconsin Brief Pain Inventory. All patients received intravenous narcotics via patient-controlled devices.
Results: Eighty surgeries were evaluated in a total of 79 women (40 per arm). Mean age was 56 years, with 79% having invasive gynecologic pathology. The two groups were not significantly different in terms of type of surgery, length of incision, estimated blood loss, operative time, or medical history. Postoperative outcomes, including wound toxicity, time to flatus, and hospital stay, did not differ. Study patients averaged 75 mg intravenously and 107 mg total narcotic use (morphine equivalent), whereas controls averaged 60 mg intravenously and 86 mg total (P = .40 intravenously; P = .25 total). Acetaminophen and intravenous ketorolac consumption were equal between groups. The Brief Pain Inventory score for "current pain" was 2.84 for bupivacaine patients and 3.14 for controls (P = .46; least = 0, most = 10). There was no individual postoperative day when "current pain" BPI scores differed. "Worst pain" and "least pain" Brief Pain Inventory scores showed similar results.
Conclusion: The results suggest that although the continuous infusion system seems safe, it is not efficacious in this patient population.