Intermittent Epidural Bolus Versus Epidural Infusion for Posterior Spinal Fusion After Adolescent Idiopathic Scoliosis

morphine given with patient- controlled intermittent bolus epidural, 50 µg/kg in 10 mL bolus, lockout time 1 hour, no infusion

morphine given with patient- controlled continuous epidural, initial setting loading morphine 0.02mg/kg in 8mL, was maintained 0.01 mg/kg continuous infusion 4mL, 0.05 mg/kg 2mL bolus dose. 30 minute lock-out interval. 4 hour limit was 4 mg/kg.