Effect of increasing depth of dexmedetomidine and propofol anesthesia on upper airway morphology in children and adolescents with obstructive sleep apnea.

STUDY OBJECTIVE: To examine the dose-response effects of dexmedetomidine (DEX) and propofol (PROP) on airway morphology in children and adolescents with a history of obstructive sleep apnea (OSA).

DESIGN: Prospective, single-blinded, controlled comparative study.

SETTING: University-affiliated teaching hospital.

PATIENTS: 60 patients with a history of OSA who presented for a magnetic resonance imaging (MRI) sleep study.

INTERVENTIONS: Patients were randomized to two equal groups (DEX or PROP). Magnetic resonance images of the airway were obtained during low (1 μg/kg/hr) and high (3 μg/kg/hr) doses of DEX, or low (100 μg/kg/m) and high (200 μg/kg/m) doses of PROP, based on group assignment.

MEASUREMENTS: The airway anteroposterior (AP) diameter, transverse diameter, and sectional areas were measured at the level of the nasopharyngeal airway and retroglossal airway. The influence of the two drugs and OSA severity, as determined by polysomnography, on airway dimensions was examined using mixed-effects analysis of covariance models.

MAIN RESULTS: Upper airway morphology was completed in 45 patients. Most airway measurements showed statistically nonsignificant associations with increasing doses of PROP and DEX. As the dosage increased, average airway dimensions were typically unchanged or slightly increased with DEX compared with airway dimensions that were unchanged or slightly decreased with PROP. An airway intervention was required in three children (11%) in the DEX group and 7 children (23%) in the PROP group (P = NS).

CONCLUSIONS: Both agents provided an acceptable level of anesthesia for MRI sleep studies in patients with OSA, with statistically nonsignificant changes in airway dimensions.