Single shot regional anesthesia for laparoscopic cholecystectomies: a systematic review and network meta - analysis.

Background: Different regional anesthesia (RA) techniques have been used for laparo-scopic cholecystectomy (LC), but there is no consensus on their comparative effectiveness. Our objective was to evaluate the effect of RA techniques on patients undergoing LC using a network meta-analysis approach.Methods: We conducted a systematic review and network meta-analysis. We searched PubMed, the Cochrane Central Register of Controlled Trials (CENTRAL), Scopus, and Web of Science (Science and Social Science Citation Index) using the following PICOS criteria: (P) adult patients undergoing LC; (I) any RA single-shot technique with injection of local anesthetics; (C) placebo or no intervention; (O) postoperative opioid consumption expressed as morphine milligram equivalents (MME), rest pain at 12 h and 24 h post -op-eration, postoperative nausea and vomiting (PONY), length of stay; and (S) randomized controlled trials.Results: A total of 84 studies were included. With the exception of the rectus sheath block (P = 0.301), the RA techniques were superior to placebo at reducing opioid consumption. Regarding postoperative pain, the transversus abdominis plane (TAP) block (-1.80 on an 11-point pain scale) and erector spinae plane (ESP) block (-1.33 on an 11-point pain scale) were the most effective at 12 and 24 h. The TAP block was also associated with the greatest reduction in PONY.Conclusions: RA techniques are effective at reducing intraoperative opioid use, postoper-ative pain, and PONY in patients undergoing LC. Patients benefit the most from the bilat-eral paravertebral, ESP, quadratus lumborum, and TAP blocks.