US-Guided PECS II Block Versus MTP Block For Postoperative Analgesia Of MRM Sugery

The patient laid supine with the ipsilateral arm abducted and externally rotated. The high-frequency linear probe was placed transversely between the clavicle medially and above and the shoulder joint laterally. After identifying the pectoralis major and minor muscles and the plane between them, the probe was angled caudally to look for the pulsating pectoral branch of the thoraco-acromial artery. After that, the block needle was inserted in an in-plane approach to the artery's location and 10 mL of 0.25% bupivacaine were administered. Then probe was moved laterally and caudally towards the anterior axillary fold until the serratus muscle appears beneath the pectoralis minor muscle attaching to the underlying ribs. The third and fourth ribs were detected. The needle targeted the plane between pectoralis minor and serratus muscles at the level of the third rib, followed by negative aspiration into the fascial plane then injection of 10 mL of 0.25% bupivacaine was done.

The block was performed with the patient in a sitting position. A high-frequency linear probe was placed in a vertical orientation 3 cm lateral to the midline at the T2 level in the parasagittal plane. The distance between the parietal pleura and the transverse process was measured using ultrasound guidance. The block needle was inserted out of plane to the probe and advanced to a depth equivalent to half of the measured distance beyond the transverse process. Then, 10 mL of 0.25% bupivacaine was injected. A similar injection was performed at the T6 level, with sonographic identification and level determination achieved by counting from the second rib.