Erector spinae plane block versus quadratus lumborum block for abdominal surgery: A systematic review and meta-analysis

Background: The erector spinae plane block (ESPB) and quadratus lumborum block (QLB) are two novel interfascial plane block techniques with possible analgesic effects for both incisional and visceral pain. However, the results of the intercomparison of the two techniques for analgesia after abdominal surgery remain controversial. Methods: A systematic literature search was performed on five databases for randomized controlled trials comparing the analgesic efficacy of ESPB and QLB in abdominal surgery. The primary outcome was the 24 h postoperative intravenous IV morphine-equivalent consumption. A meta-analysis was performed using a random-effects model, with subgroup analyses based on the types of surgery and approaches of QLB. Results: The 24 h postoperative IV morphine-equivalent consumption was lower in patients receiving ESPB than in those receiving QLB (MD -2.307 mg; 95% CI 4.577 to -0.038; p = 0.046; and I-2 = 96.5%), though the reduction did not reach clinically meaningful difference. Static and dynamic pain at different postoperative time points, the time to first rescue analgesia, and the incidence of PONV showed no significant difference between the two groups. However, the QLB group demonstrated a significantly prolonged time in performing the block compared to the ESPB group (MD -2.985 min; 95% CI -4.608 to -1.363; p < 0.001; and I-2 = 97.5%). Conclusions: Based on the available evidence from a systematic search of databases, the single-shot ESPB exhibits similar analgesic effects as QLB in abdominal surgery. The incidence of PONV was similar between the two techniques, with no block-related complications identified though QLB might be a more technically challenging approach than ESPB.