Transversus abdominis plane block versus thoracic epidural analgesia in colorectal surgery: a systematic review and meta-analysis

Background: The efficacy of transversus abdominis plane (TAP) block compared with thoracic epidural analgesia (TEA) in abdominal surgery has been controversial. We conducted this systematic review and meta-analysis to assess outcomes of TAP block and TEA in a procedure-specific manner in colorectal surgery. Methods: A systematic literature search of the PubMed, Embase, Cochrane Library, and Scopus databases was conducted through July 10, 2020, to identify randomized controlled trials (RCTs) comparing TAP block with TEA in colorectal surgery. Primary outcomes were pain scores at rest and movement at 24 h postoperatively. Secondary outcomes included postoperative pain scores at 0–2 and 48 h, opioid consumption, postoperative nausea and vomiting (PONV), functional recovery, hospital stay, and adverse events. Results: Six RCTs with 568 patients were included. Methodological quality of these RCTs ranged from moderate to high. TAP block provided comparable pain control, lower 24 h and total opioid consumption, shorter time to ambulation and urinary catheter time, and lower incidence of sensory disturbance and postoperative hypotension compared with TEA. Meanwhile, the 48-h opioid consumption, PONV incidence, and hospital stay were similar between groups. When laparoscopic surgery was the only surgical approach employed, TAP block provided additional benefits of shorter time to first flatus and lower incidence of PONV compared with TEA. Conclusions: Perhaps more germane to minimally invasive procedures, TAP block is equivalent to TEA in terms of postoperative pain control and provides better functional recovery with lower incidence of adverse events in patients undergoing colorectal surgery.