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 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.