Interscalene Block vs Serratus Posterior Superior Intercostal Plane Block

The procedure will be performed with the patient in the supine position after surgery before extubation. ESPB will be performed. The US probe will be placed longitudinally 2-3 cm lateral to the T2 transverse process. The erector spinae muscle will be visualized on the hyperechoic transverse process. The block needle will be inserted in a caudo-cranial direction, and then, for correction, 5 ml of saline will be injected deep into the erector spinae muscle fascia. Following confirmation of the correct position of the needle, 30 mL %0.25 bupivacaine will be administered for the block.

A high-frequency linear US probe (11-12 MHz, Vivid Q) will be covered with a sterile sheath, and an 80 mm block needle (Braun 360°) will be used. The procedure will be performed with the patient in the sitting position after surgery before extubation. After the scapula is shifted slightly laterally, the US probe is placed sagittal at the upper corner of the spina scapula, and the serratus posterior superior muscle is visualized with the third rib. The in-plane technique will be used. The block needle will be advanced in the craniocaudal direction to enter between the serratus posterior superior and the third rib. The block location will be confirmed by injecting 5 ml of saline between the rib and the muscle. After the block location is confirmed, 30 ml of 0.25% concentration bupivacaine will be used.

Patients will be administered ibuprofen 400 mg IV every 8 hours in the postoperative period. A patient-controlled device prepared with 10 mcg/ ml fentanyl will be attached to all patients with a protocol including a 10 mcg bolus without an infusion dose, a 10-minute lockout time, and a 4-hour limit. If the NRS score is ≥ 4, 0.5 mg kg-1 IV meperidine will be administered as a rescue analgesic. Postoperative patient evaluation will be performed by an anesthesiologist blinded to the procedure.