A randomised controlled comparison of serratus anterior plane, pectoral nerves and intercostal nerve block for post-thoracotomy analgesia in adult cardiac surgery

Background and Aims Enhanced recovery after cardiac surgery is centred around multimodal analgesia which is becoming increasingly feasible with the advent of safer regional analgesic techniques such as fascial plane blocks. We designed this prospective, single-blind, randomised controlled study to compare the efficacy of serratus anterior plane block (SAPB), pectoral nerves (Pecs) II block, and intercostal nerve block (ICNB) for post-thoracotomy analgesia in cardiac surgery. Methods 100 adults posted for cardiac surgery through a thoracotomy were randomly allocated to one of the three groups: SAPB, Pecs II or, ICNB wherein the patients received 2.5 mg/kg of 0.5% ropivacaine for ultrasound-guided block after completion of surgery. Postoperatively, intravenous (IV) paracetamol was used for multimodal and fentanyl was employed as rescue analgesia. Visual analogue scale (VAS) was evaluated at 2, 4, 6, 8, 10 and 12 hours post-extubation. Results The early mean VAS scores at 2, 4 and 6 hours were comparable in the 3 groups. The late mean VAS (8, 10 and 12 hours) was significantly lower in the SAPB and Pecs II group compared with that of the ICNB group (P value <0.05). The cumulative rescue fentanyl dose was significantly higher in ICNB group compared to SAPB and Pecs II group (P value <0.001). The SAPB group had the highest time to 1st rescue analgesic requirement in contrast to the other groups. Conclusion SAPB and Pecs II blocks are simple single-shot effective alternatives to ICNB with a prolonged analgesic duration following thoracotomy and can potentially enhance pain-free recovery after cardiac surgery.