Effect of Continuous Wound Infiltration on Patients Using Intravenous Patient-controlled Analgesia for Pain Management After Reduced-port Laparoscopic Colorectal Surgery

Purpose: Continuous wound infiltration (CWI) has been introduced as a component of multimodal analgesia to counteract the adverse effects of the most frequently used opioids. Advantages of reduced-port laparoscopic surgery (RPLS) include cosmetic benefits and decreased postoperative pain. We aimed to investigate the effect of CWI in patients using intravenous (IV) patient-controlled analgesia (PCA) for pain management after RPLS for colorectal cancer.

Methods: This retrospective study included 25 patients who received both CWI (0.5% ropivacaine infused over 72 hours) and IV PCA (fentanyl citrate) and 52 patients who received IV PCA alone. The primary endpoint was pain scores on postoperative days (PODs) 0, 1, and 2. Univariate and multivariate analyses were conducted to determine the factors affecting the pain score on POD 0.

Results: On POD 0, the mean numeric rating scale score was significantly lower in the CWI group than in the control group (3.2±0.8 vs. 3.7±0.9, P=0.042). However, the scores were comparable between the groups during the rest of the period. Within 24 hours of surgery, the CWI group consumed fewer opioids (0.7±0.9 vs. 1.3±1.1, P=0.018) and more nonsteroidal anti-inflammatory drugs (2.0±1.4 vs. 1.3±1.4, P=0.046) than the control group. Time to removal of IV PCA was significantly longer in the CWI group than in the control group (4.4±1.6 days vs. 3.4±1.0 days, P=0.016).

Conclusion: CWI with ropivacaine and IV PCA was more effective than IV PCA alone in controlling postoperative pain within 24 hours of surgery, and opioid use could be reduced further.