Interfascial Plane Blocks Reduce Postoperative Pain and Morphine Consumption in Thoracic Outlet Decompression

Background: Postoperative analgesia in patients undergoing transaxillary thoracic outlet decompression (TATOD) is challenging because of the invasive surgery, the complex innervation of the axillary region, and the preoperative use of opioids by many patients. Commonly, postoperative pain is managed with additional opioids that introduce well-known sideeffects. To investigate the analgesic efficacy of 2 novel regional anesthesia techniques, we performed a retrospective study comparing the combined pectoral block type 1 and erector spinae block (PECS 1 + ESB) and the pectoral block type 2 (PECS 2) and systemic intravenous opioids regimen (no block) in patients undergoing TATOD. Materials and methods: We performed 10 PECS 1 + ESB and 10 PECS 2 blocks in patients undergoing TATOD. Twenty patients were randomly selected as controls. The primary endpoint was pain. Secondary endpoints were opioid use, nausea, and vomiting. Results: Postoperative maximal numeric rating scale scores on recovery were significantly lower in patients receiving either a PECS 1 + ESB or a PECS 2 block compared with controls without block (no block: median 6.00, interquartile range [IQR] 3.00; PECS 1 + ESB: median 4.50, IQR 4.00; PECS 2: median 4.00, IQR 5.00; P = 0.031). Postoperative intravenous morphine consumption was 43% lower in the PECS 1 + ESB group and 56% lower in the PECS 2 group compared with the group with no block (oral morphine equivalents; no block: mean 16.05 +/- SD 6.79 mg; PECS 1 + ESB mean 9.05 +/- SD 6.24 mg; PECS 2: mean 7.00 +/- SD 6.16; P = 0.03 and P = 0.003, respectively). There was no statistical difference in both nausea and vomitus (no block 45% nausea and 30% vomitus, PECS 1 + ESB 40% nausea and 20% vomitus, PECS 2 10% nausea and 0% vomitus, P = 0.17 and P = 0.14, respectively). Conclusions: There was a significant reduction in postoperative pain and opioid consumption for patients treated with either the PECS 1 + ESB block or PECS 2.