Opioid-sparing effects of ultrasound-guided erector spinae plane block for adult patients undergoing surgery: a systematic review and meta-analysis.

BACKGROUND Erector spinae plane block (ESPB) is a new method of administering analgesics to patients perioperatively. The aim of this meta-analysis was to evaluate the opioid-sparing effects of erector spinae plane block in patients during the perioperative period compared to conventional analgesia and identify its role in the development of opioid-free anesthesia. METHODS Relevant study articles were retrieved from PubMed, the Web of Science, Medline via Ovid, Embase via Ovid, and the Cochrane Central Register of Controlled Trials (CENTRAL) on June 11, 2020. We included randomized controlled trials (RCTs) comparing the use of ESPB with control (no/sham block). The primary outcome was opioid consumption at 24h after surgery and intraoperative opioid consumption. A random-effects model was used to calculate the standardized mean difference (SMD) and odds ratio (OR) with 95% confidence interval (CI) if there was significant heterogeneity in the data, otherwise, the fixed-effect model was used. RESULTS A total of 25 randomized controlled trials involving 1461 patients were included. The use of ultrasound-guided ESPB was associated with reduced opioid consumption at 24 h after surgery [SMD: -2.14, 95% CI: -2.61 to -1.67, P<0.001] and during the intraoperative period [SMD: -2.30, 95% CI: -3.21 to -1.40, P<0.001]. In addition, it took a longer time to administer the first rescue analgesia in the ESPB group [SMD:3.60, 95% CI: 2.23 to 4.97, P<0.001] and the group was associated with lower incidences of postoperative nausea or vomiting (PONV) [OR: 0.50, 95% CI: 0.34 to 0.72, P<0.001]. CONCLUSIONS Ultrasound-guided ESPB could provide an opioid-sparing effect and effective analgesia in adults undergoing surgeries with general anesthesia, and then promote opioid-free anesthesia development.