Technology or tradition? Transversus abdominis plane block versus wound infiltration for postoperative analgesia after lower abdominal surgeries

Abstract

Background: A transversus abdominis plane (TAP) block is a fascial plane block performed to provide analgesia after surgeries with lower abdominal incisions. Ultrasound guidance has increased the success of TAP blocks. Our study compared wound infiltration, a time-tested method, with a TAP block for postoperative analgesia in lower abdominal surgeries. 
Methods: In this prospective, randomised double-blind study, 100 female patients undergoing lower abdominal surgeries with a transverse incision under spinal anaesthesia received either wound infiltration (group A) or bilateral ultrasound-guided (USG) TAP block (group B) with 30 ml of 0.75% ropivacaine after the surgery. A visual analogue scale (VAS) was used to assess analgesia at 0, 2, 4, 6, 12 and 24 h and patient satisfaction was assessed at 0 and 24 h postoperatively. We recorded the total amount of analgesic consumed in 24 h postoperatively as well as complications. 
Results: There was significantly longer duration of analgesia in group B (19.12 ± 1.92 vs 3.02 ± 1.16 h; p < 0.001), and higher patient satisfaction at 24 h (7 [5–8] vs 6 [5–8]; p < 0.001). The VAS score for pain was lower in group B at 2 h (0 [0–0] vs 1 [0–5]; p < 0.001), 4 h (0 [0–1] vs 3 [2–4]; p < 0.001), 6 h (0 [0–1] vs 3 [2–5]; p < 0.001) and 12 h (1 [0–2] vs 3 [2–4]; p < 0.001). However, the scores were similar at 0 and 24 hours. The total amount of analgesic consumed in group A was significantly higher than group B. Postoperative nausea and vomiting (PONV) was the most common event seen. 
Conclusion: USG TAP block reduces both postoperative pain scores and the amount of analgesic consumed while providing a longer duration of analgesia and better patient satisfaction compared with wound infiltration.