Comparing erector spinae plane block with serratus anterior plane block for minimally invasive thoracic surgery: a randomised clinical trial

Background: Minimally invasive thoracic surgery causes significant postoperative pain. Erector spinae plane (ESP) block and serratus anterior plane (SAP) block promise effective thoracic analgesia compared with systemically administered opioids, but have never been compared in terms of terms of quality of recovery and overall morbidity after minimally invasive thoracic surgery. Methods: Sixty adult patients undergoing minimally invasive thoracic surgery were randomly assigned to receive either single-shot ESP or SAP block before surgery using levobupivacaine 0.25%, 30 ml. The primary outcome was quality of patient recovery at 24 h, using the Quality of Recovery-15 (QoR-15) scale. Secondary outcomes included area under the curve (AUC) of pain verbal rating scale (VRS) over time, time to first opioid analgesia, postoperative 24 h opioid consumption, in-hospital comprehensive complication index (CCI) score and hospital stay. Results: The QoR-15 score was higher among ESP patients compared with those in the SAP group, mean (standard deviation): 114 (16) vs 102 (22) (P=0.02). Time (min) to first i.v. opioid analgesia in recovery was 32.6 (20.6) in ESP vs 12.7 (9.5) in SAP (P=0.003). AUC at rest was 92 (31) mm h(-1) vs 112 (35) in ESP and SAP (P=0.03), respectively, whereas AUC on deep inspiration was 107 mm h(-1) (32) vs 129 (32) in ESP and SAP (P=0.01), respectively. VRS pain on movement in ESP and SAP at 24 h was, median (25-75% range): 4 (2-4) vs 5 (3-6) (P=0.04), respectively. Opioid consumption at 24 h postoperatively was 29 (31) vs 39 (34) (P=0.37). Median (25-75%) CCI in ESP and SAP was 1 (0-2) vs 4 (0-26) (P=0.03), whereas hospital stay was 3 (2-6) vs 6 (3-9) days (P=0.17), respectively. Conclusion: Compared with SAP, ESP provides superior quality of recovery at 24 h, lower morbidity, and better analgesia after minimally invasive thoracic surgery.