SPSIP Versus RISS Block in Volume-Preserving VATS

This prospective randomized controlled study aims to compare the effects of Serratus Posterior Superior Intercostal Plane (SPSIP) block and Rhomboid Intercostal and Subserratus (RISS) block on postoperative pain, respiratory function, and recovery quality in patients undergoing volume-preserving video-assisted thoracoscopic surgery (VATS). Eighty-four patients will be randomized in a 1:1 ratio to receive either SPSIP block or RISS block. The primary outcome is the incidence of somatic pain at the chest drain insertion site at postoperative 2 hours. Secondary outcomes include pain scores, opioid consumption, quality of recovery, diaphragmatic function, pulmonary function, rescue analgesic requirements, postoperative nausea and vomiting, and block-related complications.