Ultrasound-Guided Superficial Serratus Anterior Plane Block for Cardiac Surgery with Median Sternotomy: A Retrospective Study

Objective: As part of multimodal analgesia regimen in cardiac surgery, the serratus anterior plane block (SAPB) is a technique regularly used in minimally invasive surgical interventions with thoracotomy. The aim of our study is to determine the analgesic efficacy of SAPB for cardiac surgery performed with sternotomy. Methods: A total of 99 patients who underwent SAPB (Group SAP, n=43) and conventional analgesia (Group C, n=56) for coronary artery bypass graft (CABG) surgery were compared retrospectively. Demographic data, postoperative opioid use, highest pain scores, nausea-vomiting, time to start oral intake, extubation time, lenght of intensive care unit and hospital stay were recorded. Results: Total opioid requirement, expressed in oral morphine equivalent within the first 24 hours after extubation, was found to be significantly lower in patients with SAPB (p=0.022). Similarly, both the highest reported pain scores at rest and during mobilization and also the nausea scores were found to be significantly lower in Group SAP during the same period (p=0.007, p=0.048, p=0.004). Extubation (p=0.025) and oral intake initiation time p=0.030) were shorter in Group SAP. Conclusion: By providing analgesia of the chest tube drain site, SAPB application was associated with lower opioid consumption, pain, and nausea-vomiting among patients who underwent CABG with median sternotomy. Because of this benefit, superficial SAPB may be part of opioid-reducing multimodal analgesia in cardiac surgery. Keywords: Serratus anterior plane block, fascial plane blocks, coronary artery bypass surgery, postoperative analgesia