Dexmedetomidine as Single Continuous Sedative During Noninvasive Ventilation: Typical Usage, Hemodynamic Effects, and Withdrawal.

Objectives: Dexmedetomidine use in pediatric critical care is increasing. Its prolonged effects as a single continuous agent for sedation are not well described. The aim of the current study was to describe prolonged dexmedetomidine therapy without other continuous sedation, specifically the hemodynamic effects, discontinuation strategies, and risk factors for withdrawal.

Design: Retrospective chart review.

Setting: Large, single-center, quaternary care pediatric academic institution.

Patients: Data from 382 children, less than 18 years old admitted to the PICU who received dexmedetomidine for more than 24 hours without other infusions for sedation during noninvasive positive pressure ventilation.

Interventions: Usual care practices for dexmedetomidine use were described. Discontinuation strategies were categorized as abrupt discontinuation, wean from dexmedetomidine infusion, and transition to enteral clonidine.

Measurements And Main Results: Median peak and cumulative doses with interquartile range were 1 µg/kg/hr (0.6-1.2 µg/kg/hr) and 30 µg/kg (20-50 µg/kg), respectively, and median duration was 45 hours (34-66 hr). Four hours after reaching peak dose, we observed a decrease in heart rate (p < 0.01) with 28% prevalence of bradycardia and an increase in systolic blood pressure (p < 0.01) with 33% prevalence of hypertension and 2% hypotension. During the escalation phase, the prevalence of bradycardia and hypotension were 75% and a 30%, respectively. Three-hundred thirty-six patients (88%) had abrupt discontinuation, 37 (10%) were weaned, and nine (2%) were transitioned to clonidine. Nineteen patients (5%) experienced withdrawal. Univariate risk of withdrawal was most associated with duration: odds ratio equal to 1.5 (1.3-1.7) for each 12-hour period (p < 0.01). By multivariate analysis including age, discontinuation group, dexmedetomidine cumulative dose, and peak dose, only cumulative dose remained significant with an odds ratio equal to 1.3 (1.1-1.5) for each 10 μg/kg (p < 0.01).

Conclusions: Dexmedetomidine use for noninvasive positive pressure ventilation sedation in pediatric critical care has predictable hemodynamic effects including bradycardia and hypertension. Although withdrawal was associated with higher cumulative dose, these symptoms were effectively managed with short-term enteral clonidine.