Comparison of Continuous Wound Infusion versus Continuous Epidural Infusion in Upper Abdominal Surgery: Noninferiority Randomized Controlled Trial

CONTEXT: Wound catheter offers a less invasive alternative for postoperative analgesia in the abdominal surgery. METHODS: We conducted a single-center, prospective, open-label noninferiority randomized controlled trial. A total of 40 patients who consented to this trial, undergoing upper abdominal surgery via an upper midline incision, were randomized into two groups. In the continuous wound infusion (CWI) group, the wound catheter was placed in the subcutaneous plane of the surgical incision; the continuous epidural infusion (CEI) group received thoracic epidural with a catheter placed. After the surgery, both the groups received 0.2% ropivacaine infusion at 10 mL/h following a 10 mL bolus for 48 h postsurgery. Postoperatively, the pain scores were noted at multiple time points, along with a record of morphine consumption and adverse effects. RESULTS: There was no significant difference in pain scores both at rest and on movement between the two groups at all the time points assessed. The mean difference in numerical rating scale score 24 h postsurgery at rest (0.1, 95% confidence interval [CI] = −0.45, 0.65) and on movement (0.05, 95% CI = −0.73, 0.83), with 95% CI in both the groups, was within the noninferiority limit. Morphine consumption was less in the CEI group, though not significant. The time to appearance of bowel movement, time to ambulate, and length of hospital stay were significantly lower in the CWI group. The incidence of hypotension requiring intervention was higher in the CEI group. CONCLUSION: Hence, analgesia provided by continuous wound catheter infusion is not inferior to CEI with better preservation of hemodynamics and faster recovery.