Parasternal Intercostal Block Complementation Contributes to Postoperative Pain Relief in Modified Radical Mastectomy Employing Pectoral Nerve Block I and Serratus-Intercostal Block: A Randomized Trial

Purpose: Pectoral nerve block I (PECS I) and serratus-intercostal plane block (SIPB) can anesthetize the majority mammary region, while parasternal intercostal block (PSI) targets the internal area during breast resection surgery. The aim of this study was to determine whether including PSI with PECS I and SIPB is more effective compared to PECS I and SIPB alone. Patients and Methods: Sixty-two adult females undergoing unilateral modified radical mastectomy (MRM) were randomly assigned to receive either PECS I and SIPB (PS group, n=31) or a combination of PECS I, SIPB, and PSI (PSP group, n=31). The outcomes were measured with a numerical rating scale (NRS) score, and in terms of opioid consumption and anesthesia-related complications within 48 h after surgery. Results: Although there were no differences in the NRS scores between the two groups during the inactive periods, the combination of three nerve blocks significantly reduced the NRS scores during movement. In addition, morphine equivalent consumption was lower in the PSP group compared to the PS group. Postoperative adverse events were similar in both groups in terms of regional anesthesia-related complications. Conclusion: The combination of PECS I block, SIPB, and PSI block provides superior pain relief and postoperative recovery for patients undergoing MRM.