A Prospective Randomised Study to Assess the Analgesic Efficacy of Serratus Anterior Plane (SAP) Block for Modified Radical Mastectomy Under General Anaesthesia

OBJECTIVE: Breast cancer is the most common malignancy among women and often requires surgery for the removal of the tumour. Uncontrolled pain after breast surgeries is a common problem. Serratus anterior plane (SAP) block is a recently designed technique to block the lateral cutaneous branches of the ventral rami of thoracic intercostal nerves and may cover the area of surgical dissection for modified radical mastectomy (MRM). The primary objective of this study was to evaluate the effect of SAP block on the time to first rescue analgesic in the post-operative period in patients undergoing MRM. METHODS: A randomised, single-blind, parallel group trial was conducted in a single teaching hospital. A total of 100 patients undergoing MRM were randomised in a 1:1 ratio into 2 groups: MRM under general anaesthesia (GA) alone (group G, n=50) or GA with SAP block (group S, n=50). Blocks were performed under ultrasound guidance at the level of the 5(th) rib in the midaxillary line with 0.4 mL kg(−1) of 0.375% ropivacaine. RESULTS: The time to request of first rescue analgesia was significantly prolonged in group S compared with group G (p=0.008). Median (interquartile range) for time to rescue analgesia in group S was 120 (60–300) min, whereas in group G, it was 60 (15–120) min. Post-operative pain scores and the number of patients requiring intra-operative additional fentanyl were significantly less in group S. No technique-related adverse events were observed. CONCLUSION: SAP block improved perioperative analgesia in patients undergoing MRM. CLINICAL TRIAL REGISTRY NUMBER: CTRI/2017/11/010424. (http://ctri.nic.in/Clinicaltrials/regtrial.php?modid=1&compid=19&EncHid=45912.14862)