Safety and Effectiveness of Intramuscular Dexmedetomidine Versus Per-Rectal Thiopental for Pediatric Brain Computed Tomography Sedation: A Retrospective Cohort Study.

OBJECTIVES: Following per-rectal thiopental (PR-THP) supply discontinuation, a tertiary pediatric emergency department in Korea transitioned to intramuscular dexmedetomidine (IM-DEX) for brain computed tomography (CT) sedation. We evaluated the safety and effectiveness of this protocol. METHODS: We conducted a retrospective cohort study of alert children aged 1 month to 18 years undergoing brain CT sedation for traumatic head injury, comparing the PR-THP era (Jan 2024 to Mar 2025) with the IM-DEX era (May 2025 to Apr 2026). The primary outcome was safe CT completion: scan completion without a moderate-to-severe adverse event (respiratory event grade ≥2 or bradycardia requiring pharmacologic intervention). Secondary outcomes included rescue-free completion and sedation timeline metrics. RESULTS: Among 246 completed sedation episodes (137 PR-THP, 109 IM-DEX), baseline characteristics were generally similar. Safe CT completion was 97.1% versus 99.1% (risk difference +2.0 percentage points, 95% CI: -1.3 to +5.3; P=0.386). Rescue-free completion was 86.9% versus 82.6% (adjusted OR 0.72, 95% CI: 0.35-1.45). Moderate-to-severe adverse events occurred in 4 (2.9%) PR-THP and 1 (0.9%) IM-DEX episodes; no episode required bradycardia intervention. Bradycardia by predefined criteria was more frequent with IM-DEX (24.8% with PR-THP vs. 39.4% with IM-DEX), without documented perfusion compromise. Median time to documented sedation was 9 versus 10 minutes; mean time was longer with IM-DEX (9.1 vs. 11.3 min). Median recovery time was 32 minutes with PR-THP and 18 minutes with IM-DEX (P=0.080), and total sedation time was similar (median 53 vs. 47 min; P=0.890). CONCLUSIONS: IM-DEX served as a pragmatic, cannulation-free initial sedation strategy, with no clear excess in clinically significant adverse events and similar total sedation time. In alert children with traumatic head injury, IM-DEX may be a feasible sedation option when intravenous access is undesirable; findings should be applied with caution outside this population.