Association between intranasal dexmedetomidine dose and delayed awakening after sedation in children: a retrospective cohort study

BACKGROUND: Intranasal dexmedetomidine is widely used in pediatric procedural sedation; however, its dose-related effect on delayed awakening remains insufficiently characterized. METHODS: This single-center retrospective cohort study included pediatric patients who received oral midazolam combined with intranasal dexmedetomidine for procedural sedation at the Sedation Center of Guangxi Zhuang Autonomous Region Maternal and Child Health Hospital between March 2022 and March 2024. The exposure was the intranasal dexmedetomidine dose (μg/kg). The primary outcome was delayed awakening, defined as a time of ≥ 90 min from the last sedative administration (including rescue/secondary sedatives when applicable) to full awakening documented by the anesthesiologist on duty using routinely recorded standardized criteria (Modified Aldrete score ≥ 9). Firth penalized multivariable logistic regression models were applied to evaluate the association between dexmedetomidine dose and delayed awakening, adjusting for age group, sex, weight, fasting duration, procedure type, and midazolam dose. Dose-response relationships and subgroup analyses restricted to baseline/procedural characteristics were also conducted. RESULTS: A total of 2,116 children were included, with an overall delayed awakening incidence of 2.6%. When stratified by tertiles of dexmedetomidine dose, the incidence of delayed awakening increased from 1.1% in the low-dose group to 2.9% in the medium-dose group and 4.1% in the high-dose group (P = 0.004). In multivariable analyses, each 1 μg/kg increase in intranasal dexmedetomidine dose was associated with a significantly higher risk of delayed awakening (adjusted odds ratio [OR] 3.665, 95% confidence interval [CI] 2.091-6.636; P < 0.001). Dose-response analysis demonstrated a positive linear association (no evidence of nonlinearity, P = 0.451) between dexmedetomidine dose and delayed awakening. This corresponds to an aOR of 1.91 per 0.5 μg/kg increase (and 1.99 per IQR increase); adjusted predicted probabilities were 0.96% at 2 μg/kg, 3.37% at 3 μg/kg, and 10.70% at 4 μg/kg. CONCLUSIONS: In pediatric procedural sedation, higher intranasal dexmedetomidine dose is associated with delayed awakening and demonstrates a positive dose-response relationship. Younger children appear to be more susceptible to this adverse outcome. Clinically, dexmedetomidine dosing should be carefully individualized-particularly in younger patients-to balance effective sedation with recovery efficiency.