Erector Spinae Plane Block Versus Quadratus Lumborum Block for Open Renal Surgeries in Children

Open renal surgeries are associated with significant postoperative pain; early control of the perioperative pain is associated with decrease of hemodynamic variations during the surgery, early mobilization, better quality of functional recovery & early discharge of patients. Side effects of systemic opioids, as well as difficulty to monitor their response, are major limitations to their use. Pediatric regional anesthesia (PRA) is one of the most valuable and safe tools to treat perioperative pain, and is an essential part of modern anesthetic practice. Neuraxial analgesia for pediatric patients is a mode of pain control that gained popularity in the last few decades as it decreases opioid exposure, shortens recovery room time & hospital stay. Caudal block is the most commonly used neuraxial anesthesia in pediatric patients. However, its major side effect is urinary retention and excessive motor block. Considerable progress has been made in the practice of PRA over the past few years including incorporation of ultrasound guidance, with promising novel regional anesthesia techniques, especially the anterolateral and the posterolateral trunk blocks. In this study, the investigators will compare the ultrasound guided quadratus lumborum block (QLB) with erector spinae plane block (ESPB), regarding the duration and quality of postoperative analgesia in pediatric patients undergoing unilateral open renal surgeries under general anesthesia. The study hypothesis is that QLB can provide a more superior postoperative pain relief to ESPB in children undergoing open renal surgeries.