Effect of local wound infiltration and transversus abdominis plane block on morphine use after laparoscopic colectomy: A nonrandomized, single-blind prospective study

Background Recently, nonopioid-based treatment modalities have been used to improve analgesia and decrease opioid-related side effects after surgery. Transversus abdominis plane (TAP) block and local infiltration of the surgical wound are commonly used multimodal analgesia techniques after abdominal surgery; however, few studies have compared the effectiveness of a TAP block with that of local infiltration of surgical wounds in patients who have undergone laparoscopic colorectal surgery. Materials and methods Sixty patients undergoing laparoscopic colorectal surgery participated in this prospective comparative study. All patients were allocated to 1 of 2 groups as follows: the TAP group or the infiltration group. Patients in the TAP group received bilateral TAP blocks at the end of the surgery. Patients in the infiltration group received local infiltration of anesthetics in the surgical wounds after closure of the peritoneum. All patients received postoperative analgesia with morphine as a patient-controlled analgesia. Opioid consumption and pain scores were recorded at 2, 6, 24, and 48 h after the operation. Results The characteristics of patients in the TAP group (n = 30) and local infiltration group (n = 29) were comparable. Pain scores while coughing and at rest were not different between the two groups. Postoperative morphine use was significantly reduced in the TAP group compared with that in the local infiltration group at 2-6 h (2.9 ± 1.9 mg versus 4.5 ± 3.2 mg, P = 0.02), 6-24 h (5.5 ± 3.3 mg versus 10.2 ± 8.4 mg, P = 0.00), the first 24 h (16.6 ± 6.6 mg versus 24.0 ± 9.7 mg), and 48 h (23.6 ± 8.2 mg versus 31.8 ± 12.5 mg, P = 0.00). No differences in rescue analgesic use or side effects were noted between the groups. Conclusions Compared with local anesthetic infiltration, bilateral TAP blocks decreased the cumulative morphine use at 24 h and 48 h postoperatively in patients who had undergone laparoscopic colorectal surgery.