Serratus Posterior Superior Plane Block in Minimally Invasive Cardiac Surgery

This prospective randomized controlled trial aimed to evaluate the efficacy of serratus posterior superior intercostal plane block (SPSIPB) as a component of a multimodal analgesia strategy for postoperative pain control, opioid consumption, and hemodynamic response in patients undergoing mini-thoracotomy cardiac surgery. The study was planned to include a total of 60 patients, with 30 patients in each group. Patients with ASA physical status I-III scheduled for elective mini-thoracotomy cardiac surgery (coronary artery bypass grafting, valve replacement, atrial septal defect closure, or beating-heart bypass) will be randomized to the SPSIPB group or a control group receiving standard analgesic management without any regional block. The primary outcome is the resting Numeric Rating Scale (NRS) pain score at 1 hour postoperatively. Secondary outcomes include resting and movement (passive shoulder flexion) NRS pain scores at 1, 4, 8, 16, and 24 hours, cumulative 24-hour tramadol consumption, proportion of patients requiring rescue analgesia, intraoperative remifentanil consumption, systolic blood pressure change at incision, incidence of postoperative nausea and vomiting (PONV), patient satisfaction (5-point Likert scale), time to extubation, and intensive care unit length of stay.

Inclusion Criteria: * Adults aged 18 years or older * American Society of Anesthesiologists (ASA) physical status I - III * Scheduled for elective minimally invasive coronary artery bypass surgery * Ability to understand the study procedures and provide written informed consent Exclusion Criteria: * Age under 18 years * ASA physical status other than I - III * Pregnancy * Emergency surgery * History of trauma within the previous 24 hours * Neurological disorders affecting consciousness or decision-making capacity * Psychiatric disorders affecting decision-making capacity or cooperation * Known allergy to local anesthetic agents * Infection or skin disease at the block injection site * Body mass index greater than 35 kg/m² * Body weight less than 42 kg * Coagulation disorders (international normalized ratio \>1.25, activated partial thromboplastin time \>35 seconds, or platelet count \