Intertransverse Process Block for Postoperative Analgesia After Thoracotomy and Lobectomy

This prospective, randomized, triple-blind, placebo-controlled clinical trial will investigate the effectiveness of the intertransverse process block (ITPB) for postoperative analgesia in patients undergoing elective thoracotomy with unilateral lobectomy. The study will be conducted at a single tertiary center in accordance with the principles of the Declaration of Helsinki, and written informed consent will be obtained from all participants.

Patients will be randomized in a 1:1 ratio to receive either ultrasound-guided ITPB with 0.5% bupivacaine or placebo (normal saline) prepared in identical syringes to ensure allocation concealment. The block will be performed by an experienced anesthesiologist immediately after surgery and before emergence from anesthesia. Both groups will receive standardized general anesthesia, multimodal perioperative analgesia, and postoperative intravenous morphine patient-controlled analgesia (PCA).

The trial aims to evaluate the analgesic efficacy and opioid-sparing effect of ITPB while maintaining safety and adherence to routine clinical practice. Outcomes will include postoperative pain scores, opioid consumption, rescue analgesia requirement, and adverse events.