Ultrasound-guided Bilateral Quadratus Lumborum Block Versus Erector Spinae Block for Postoperative Analgesia in Laparoscopic Cholecystectomy

on arrival to the operative room all patients were monitored with standared monitoring. then IV cannula were inserted. preoxygenation with 100% oxygen and induction of GA by 1mic/kg fentanyl and 2 mg/kg of 1%propofol. endotracheal intubation was facilitated by 0.5mg/kg of atracurium. isoflurane 1-2% with oxygen was used for anesthetic maintenance and 0.15 mg/kg intermittent doses of atracurium to maintain adequate muscle relaxation. ventilation was controlled to maintain end tidal CO2 at 35-40 mmHg and SaO2 between 95-100. after stabilization of the patient's hemodynamics and before surgical incision, quadratus lumborum and erector Spinae block were performed according to patient's group by the same anesthetist with the patient in lateral or prone position respectively.