Remifentanil vs Fentanyl in Children 7-12 After Urologic Surgery: Emergence Delirium and Recovery Quality

Emergence delirium (agitation) is a common complication in children recovering from general anesthesia, especially after sevoflurane. Affected children wake in a dissociative state - restless, crying, inconsolable, unaware of their surroundings - with a reported incidence of 25-80%. It raises the risk of self-injury, accidental catheter removal, vomiting, and maladaptive behavior persisting for weeks, and prolongs hospital stay. Short-acting opioids such as fentanyl and remifentanil are widely used in pediatric anesthesia for sedation and analgesia and to blunt the hemodynamic response to surgical stimulation and airway instrumentation. Both have been proposed to reduce emergence agitation after sevoflurane anesthesia, but findings for remifentanil are inconsistent: some studies report a reduction, others an increase. Clinicians therefore lack clear guidance on opioid selection for maintenance. This trial compares intraoperative remifentanil with intraoperative fentanyl maintenance on the occurrence of emergence delirium in children undergoing urologic surgery under general anesthesia. Secondary aims are postoperative recovery, duration of surgery, and intraoperative hemodynamics. Design: single-center randomized controlled trial. 176 children aged 7-12 years, ASA I-II, scheduled for elective pediatric urologic surgery, randomized 1:1 (88 per group). All participants receive the same background technique: intravenous midazolam 0.05 mg/kg five minutes before entering the operating room; standard monitoring (ECG, pulse oximetry, non-invasive blood pressure, capnography); induction with propofol 3-5 mg/kg; laryngeal mask airway (LMA); sevoflurane titrated to 1 MAC; and preemptive intravenous paracetamol and ketamine 0.3 mg/kg after induction. The fentanyl group receives fentanyl 1 mcg/kg after loss of consciousness, then 1 mcg/kg every 30 minutes until the end of surgery. The remifentanil group receives remifentanil 0.5 mcg/kg, then an infusion of 1 mcg/kg/min. In both groups the LMA is inserted 90 seconds after the bolus. At the end of surgery sevoflurane is discontinued and the LMA removed once the child breathes regularly and moves purposefully without stimulation. Emergence delirium is assessed in the post-anesthesia care unit with the Pediatric Anesthesia Emergence Delirium (PAED) scale (0-20). Additional measurements include time from sevoflurane discontinuation to LMA removal, time to eye opening on verbal stimulus, and readiness for discharge.

Inclusion Criteria: * Age 7 to 12 years * American Society of Anesthesiologists (ASA) physical status I or II * Scheduled for elective pediatric urologic surgery * Surgery planned under general anesthesia with a laryngeal mask airway * Written informed consent from a parent or legal guardian, with assent from the child Exclusion Criteria: * History of difficult airway or known airway abnormality * Reactive airway disease * Respiratory tract infection within the preceding 3 weeks * Abnormal cognitive development or developmental delay * Known allergy to any medication used in the study protocol * Chronic use of opioids, sedatives, or psychoactive medication