The Effect of Intranasal Administration of Remifentanil on Intubating Conditions and Airway Response After Sevoflurane Induction of Anesthesia in Children:

BACKGROUND: Intubation without the use of muscle relaxants in children is frequently done before IV access is secured. In this randomized controlled trial, we compared intubating conditions and airway response to intubation (Coughing and/or movement) after sevoflurane induction in children at 2 and 3 min after the administration of intranasal remifentanil (4 mcg/kg) or saline. METHODS: One hundred eighty-eight children, 1-7-yr old, were studied. Nasal remifentanil (4 mcg/kg) or saline was administered 1 min after all 8% sevoflurane N2O induction. The sevoflurane concentration was then reduced to 5% in oxygen, and ventilation assisted/controlled. An anesthesiologist blinded to treatment assignment used a validated score to evaluate the conditions for laryngoscopy and response to intubation. Blood samples for determination of remifentanil blood concentrations were collected from 17 children at baseline, 2, 3, 4, and 10 min after nasal administration of remifentanil. RESULTS: Good or excellent intubating conditions were achieved at 2 min (after the remifentanil bolus) in 68.2%, and at 3 min in 91.7% of the children who received intranasal remifentanil versus 37% and 23% in children who received placebo (P < 0.01). The mean remifentanil plasma concentrations (+/- SD) at 2, 3, 4, and 10 min were 1.0 (0.60), 1.47 (0.52), 1.70 (0.46), and 1.16 (0.36) ng/mL, respectively. Peak plasma concentration was observed at 3.47 min. There were no complications associated with the use of nasal remifentanil. CONCLUSIONS: Nasal administration of remifentanil produces good-to-excellent intubating conditions in 2-3 min after sevoflurane induction of anesthesia.