Rhomboid Intercostal and Sub-serratus Block

Following endotracheal intubation, patients allotted to the RIB group were positioned in the lateral decubitus position with the chest on the operating side lying superiorly. The ipsilateral arm was abducted from the chest to move the scapula laterally. The RIB was performed as described previously \[8\]. A high-frequency (6-12 MHz) linear ultrasound probe (LOGIQ e ultrasonic system, Deutschland GmbH \& Co. KG, Solingen, Germany) was placed medial to the medial border of the scapula in the oblique sagittal plane. The landmarks, i.e., the trapezius muscle, rhomboid muscle, intercostal muscles, pleura, and lung, were identified in the ultrasound. Under aseptic conditions, an 80-mm 21-gauge needle was inserted at the level of T6-7 in the ultrasound view. A single dose of 30 ml 0.25% bupivacaine will be injected in the interfascial plane between the rhomboid major and intercostal muscles. The spread of the local anesthetic solution under the rhomboid muscle was visualized by ultrasonography.

Following endotracheal intubation, patients will be received morphine sulfate (0.02 mg/kg) bolus doses were used to preserve MAP and HR within 20% of pre-induction readings