Ultrasound Guided Erector Spinae Muscle Block in Pediatric Surgeries

In the ESB group, the patient will be placed in the lateral position. The site of surgery is upward. After skin preparation using 10% povidone-iodine, a high-frequency linear ultrasound transducer will be placed over the ipsilateral site of surgery 1-2 cm lateral to the spine at the T10 level, counting upward from the sacrum. After identifying the erector spinae muscles and transverse process, a needle will be inserted with an in-plane technique in the craniocaudal direction

In the CB group, patients will be placed in a lateral position. An ultrasound transducer is first placed transversely at the midline to obtain a transverse view of the 2 cornua, the sacrococcygeal ligament, sacral bone, and sacral hiatus. At this position, the ultrasound transducer will be twisted to 90° to obtain longitudinal views of the sacrococcygeal ligament and sacral hiatus and will be subsequently placed between the 2 cornua and on visualization of the frog sign (the 2 sacral cornua identified as 2 hyperechoic reverse U-shaped structure) the needle will be inserted into the sacral canal under direct real-time longitudinal visualization. After negative aspiration for blood or cerebrospinal fluid, bupivacaine (0.25%) 2.5 mg/kg will be injected over a one minute period while observing an ultrasound longitudinal image.