Ultrasound Guided Rhomboid Intercostal Nerve Block Versus Erector Spinae Plane Block for Postoperative Analgesia in Modified Radical Mastectomy:A Comparative Study

The aim of this study is to compare the post-operative analgesic effect of ultrasound-guided rhomboid intercostal nerve block versus erector spinae plane block as regard total analgesic requirements, duration of effective analgesia,postoperative visual analog score (VAS), peri-operative hemodynamics,peri-operative complications and incidence of chronic postmastectomy pain.The technique of rhomboid intercostal nerve block:

After induction of anesthesia, the patient will be positioned in lateral decubitus with the operated side above. After sterilization of the patient's back, A linear ultrasound transducer (6-12 MHz) will place medial to the lower border of the scapula with the orientation marker directed cranially. The ultrasound landmarks, trapezius muscle, rhomboid muscle, intercostal muscles, pleura, and lung will be identified. The tissue plain between the rhomboid major and intercostal muscles is identified, and a single injection is administered at the T4-5. 80mm 21-gage needle will be inserted in the plane view of the ultrasound probe at the level of T4-5. After negative aspiration of blood or air, the rhomboid intercostal plane was hydro located with 2 mL of normal saline to confirm the correct needle tip position. A single injection of 30 ml of bupivacaine 0.25% will be applied into the interfacial plane between the rhomboid major and intercostal muscles. The spread of local anesthetic solution under the rhomboid muscle will be visualized by ultrasonography.

The technique of Erector spinae plane block (ESP):

After induction of anesthesia, the patient will be positioned in lateral decubitus with the operated side above. After sterilization of the patient's back, A linear ultrasound probe willplace 3-cm lateral to the midline at the level of T5 interspinous space and transverse process and three muscles willidentify: trapezius, rhomboid major, and erector spinae. A 10-cm needle was inserted craniocaudally in-plane, to reach the transverse process. After hydrodissection of the plane with 3 mL of normal saline, 30 ml of 0.25% bupivacainewilldeposit and thus erector spinae muscle will lift off the transverse process.

Block assessment will be performed using ice cube withtemperature of 4°C at midclavicular linein post anesthesia care unit after Full recovery which be confirmed when Aldrete's score ≥9 .