Breast cancer is the most frequent cancer among Indian women accounting for 25 to 32 per cent. Surgical resection of the primary tumour with axillary dissection is one of the most important therapeutic procedures for breast cancer. Most breast surgeries are done in general anaesthesia, with or without regional blocks. Forty per cent of women experience moderate to severe pain following breast cancer surgery in the first few days.

Various regional anaesthesia techniques including thoracic paravertebral block, Erector spinae plane block, PEC block etc. have been used for perioperative analgesia in breast cancer surgery to decrease opioid consumption and its side effect. Poor management of acute postoperative pain may lead to persistent postoperative pain with an incidence of 25 to 60% of patients. These blocks are found to be effective for postoperative analgesia and also decrease the incidence of post-mastectomy pain syndrome. The paravertebral block is considered the gold standard for breast surgery but this block is associated with many complications. Recently interfacial blocks (pectoral nerve blocks) have been used for post-op analgesia in breast surgery. 

This study aims to compare the efficacy of ultrasound-guided combined pectoral nerve block and pecto intercostal fascial block with thoracic paravertebral block for perioperative analgesia for MRM, and to find which requires less opioid consumption, better NRS, fewer complications, a better patient satisfactory score.