Analgesic Efficacy of U/S Retrolaminar Block and Erector Spinae Plane Block in MRM

"The ultrasound probe was placed on the back in a transverse orientation on the lateral side of the posterior median line to identify the lamina of the 5th vertebra, ESM, and transversospinalis muscles of the target segment.~A 38-mm 22-gauge regional block needle was advanced using an in-plane technique. When the puncture needle touched the lamina, 20 mL of 0.25% levobupivacaine was administered between the transversospinalis muscle and lamina. The LA diffusion between the lamina and the ESM indicated a successful puncture."

"The ultrasound probe was placed on the back in a transverse orientation to identify the tip of the T5 transverse process as flat, squared-off acoustic shadows with a faint image of the pleura visible. When the tip of the transverse process was centered on the ultrasound screen, the probe was rotated to a longitudinal orientation. In the parasagittal view, the following layers were visible superficial to the acoustic shadows of the transverse processes: skin and subcutaneous tissue, trapezius, ESM, and T5 transverse process.~The block needle was inserted in-plane in a cranial-to-caudal direction until contact was made with the T5 transverse process. The correct location of the needle tip in the fascial plane deep to the ESM was confirmed by injecting 0.5-1.0 ml of normal saline and seeing the fluid lifting the ESM off the transverse process without distending the muscle. Then 20 ml levobupivacaine 0.25% was injected."