Intranasal dexmedetomidine versus intranasal dexmedetomidine combined with rectal chloral hydrate for sedation of young children undergoing transthoracic echocardiography: a prospective observational cohort study

Abstract Background To evaluate the safety and efficacy of intranasal dexmedetomidine (DEX) alone versus intranasal low-dose DEX combined with rectal chloral hydrate (CH) for sedation of young children during transthoracic echocardiography (TTE) examination. Methods We conducted a 16-month prospective observational cohort study of children aged 1–36 months who underwent sedation for TTE examination. Participants received either 2 µg/kg intranasal DEX (Group DEX) or 1 µg/kg intranasal DEX combined with 20 mg/kg rectal CH (Group DEX-CH). The primary outcome was efficacy, defined as the initial sedation success rate. Secondary outcomes included the sedation onset time, the recovery time, the duration of sedation, and adverse events. Multivariable logistic regression and propensity score matching were used to adjust for confounding factors. Results A total of 2,776 children were enrolled, of whom 1,437 (51.8%) received DEX sedation and 1,339 (48.2%) received DEX-CH sedation. After 1:1 propensity score matching, 1,253 children remained in each group. DEX-CH sedation was independently associated with a higher initial success rate (Group DEX 93.2% vs. Group DEX-CH 98.2%; relative risk [RR] 0.26; 95% confidence interval [CI] 0.16–0.41; P < 0.001). Group DEX-CH had a longer duration of sedation [36 (27, 50) min vs. 44 (34, 55) min; P < 0.001] and recovery time [13 (3, 25) min vs. 20 (10, 32) min; P < 0.001]. Group DEX had fewer adverse events (5.3% vs. 8.4%; RR 0.61; 95% CI 0.44–0.84; P = 0.002). Sedation onset time did not differ between the groups. Conclusions In real-world hospital settings, 1 µg/kg intranasal DEX combined with 20 mg/kg rectal CH for sedation of young children undergoing TTE examination was associated with a higher initial sedation success rate and a longer duration of sedation, whereas 2 µg/kg intranasal DEX was associated with fewer adverse events.