Comparison of Midpoint Transverse Process to Pleura Block and Thoracic Paravertebral Block

Patients between the ages of 18 to 80, scheduled for Video-Assisted Thoracoscopic Surgery (VATS) and classified under the American Society of Anesthesiologists (ASA) class I and II, will be included in the study. Patients with known or suspected local anesthetic allergies, coagulopathy, site injection infections, a history of thoracic surgery, severe neurological or psychiatric disorders, severe cardiovascular diseases, liver failure, kidney failure (glomerular filtration rate \<15 ml/min/1.73 m2), and chronic opioid use will be excluded from the study. Demographic information of the patients (name, protocol number, weight, height, age, body mass index, comorbidities, ASA score) will be recorded. Subsequently, after necessary information is provided, and written and verbal consent is obtained, patients will be randomized into three groups: Group MTPB: After the induction of general anesthesia and intubation in the operating room, the patient will be placed in the lateral decubitus position. Using ultrasound guidance, a linear probe will be used to perform a MTPB at the midpoint of the superior costotransverse ligament at the level of the 5th intercostal space. A 0.5 ml/kg solution of 0.25% bupivacaine will be administered in-plane. Group PVB: After the induction of general anesthesia and intubation in the operating room, the patient will be placed in the lateral decubitus position. Using ultrasound guidance, a linear probe will be used to perform a paravertebral block (PVB) at the level of the 5th intercostal space. A 0.5 ml/kg solution of 0.25% bupivacaine will be administered in-plane. Group P: No peripheral block will be performed in this group. All patients' hemodynamic data (mean arterial pressure, heart rate, oxygen saturation) will be recorded at 30-minute intervals during the intraoperative period, as well as the amount of opioids used during the surgery. Fifteen minutes before awakening, an intravenous patient-controlled analgesia (PCA) device will be connected, delivering a bolus dose of 2 ml of 1 mg/ml morphine solution with a lockout time of 15 minutes. During the postoperative period, visual analog pain scores (VAS) will be assessed at 0, 30 minutes, 1, 2, 4, 8, 12, 24, 36, and 48 hours, both at rest and during coughing. Additionally, the time to first analgesic requirement, total analgesic consumption, need for rescue analgesia (contramal 100 mg/2 ml), amount required, possible opioid side effects (nausea, vomiting, respiratory depression, sedation), and time to awakening will be recorded. The time to first mobilization, postoperative complications, time to discharge, and satisfaction of both patients and the surgical team will be recorded using a 5-point Likert scale.