Comparison of the analgesic effect between continuous wound infiltration and single-injection transversus abdominis...

Both single-injection transversus abdominis plane (TAP) block and continuous wound infiltration (CWI) provide postoperative analgesia, but no study has compared the two regional techniques. We tested the hypothesis that CWI is more effective for controlling postoperative pain compared with single-injection TAP block after laparotomy.

We conducted a prospective randomized study of patients undergoing gynecologic laparotomy with midline incision through the umbilicus under general anesthesia. The patients were allocated to receive either single-injection TAP block (TAP group) or CWI (CWI group) for postoperative analgesia. All patients received intravenous patient-controlled analgesia with morphine and intravenous flurbiprofen twice daily after surgery. Postoperative pain at rest and on coughing, postoperative morphine consumption, incidence of postoperative nausea and vomiting (PONV), pruritus and urinary retention, ambulation, and satisfaction score were recorded. Patients were assessed at 3 h after surgery and twice daily on postoperative days (POD) 1 and 2.

Data of 54 patients were analyzed. Compared to the TAP group (n = 27), pain score on coughing was significantly lower in the CWI group (n = 27) on POD1 and POD2 (P < 0.05). Pain score on coughing at 3 h after surgery, pain score at rest at all assessed time points, morphine consumption, incidence of PONV, pruritus and urinary retention, ambulation, and satisfaction score were not different between the two groups.

CWI reduced pain on coughing after the day of surgery compared with single-injection TAP block when performed as part of multimodal analgesia in patients undergoing gynecologic laparotomy.