Abstract
BackgroundSedation is frequently required to ensure motion-free diagnostic imaging in children, particularly for magnetic resonance imaging (MRI) and computed tomography (CT). Midazolam remains widely used in many tertiary hospitals due to familiarity and accessibility; however, concerns persist regarding respiratory depression, agitation, and prolonged recovery. Dexmedetomidine has emerged as an alternative with a potentially superior respiratory safety profile and smoother recovery, but its hemodynamic effects warrant careful evaluation. This randomized controlled trial compared dexmedetomidine and midazolam for pediatric diagnostic imaging sedation in a tertiary healthcare centre in Lahore, Pakistan.
ObjectiveTo compare the safety profile and recovery outcomes of dexmedetomidine versus midazolam in pediatric patients undergoing diagnostic imaging, with specific emphasis on hemodynamic stability, respiratory adverse events, recovery time, and discharge readiness.
Study type: Randomized controlled trial
MethodsA prospective, parallel-group randomized controlled trial was conducted at a tertiary teaching hospital in Lahore. Children aged 6 months to 12 years requiring sedation for MRI or CT were enrolled and randomized (1:1) to receive either dexmedetomidine (n=60) or midazolam (n=60) using a concealed allocation process. Standard monitoring was applied, including continuous pulse oximetry, heart rate, and non-invasive blood pressure.
Primary outcomes were recovery time and time to discharge readiness.
Secondary outcomes included respiratory events (desaturation, airway intervention), hemodynamic instability (bradycardia, hypotension), agitation, need for rescue sedation, and imaging success rate. Outcomes were analyzed under an intention-to-treat framework.
A total of 120 children were randomized and included in analysis. Baseline characteristics were comparable between groups. The dexmedetomidine group demonstrated significantly improved recovery efficiency:
- Recovery time was shorter with dexmedetomidine (2 ± 13.1 min) than midazolam (48.9 ± 15.1 min).
- Discharge readiness occurred earlier with dexmedetomidine (5 ± 16.0 min) compared with midazolam (78.9 ± 21.5 min).
Respiratory safety favored dexmedetomidine:
- Oxygen desaturation occurred in 7% with dexmedetomidine vs 20.0% with midazolam.
- Airway interventions were uncommon but slightly lower with dexmedetomidine (3%) than midazolam (5.0%).
Hemodynamic effects were more frequent with dexmedetomidine:
- Bradycardia: 3% vs 5.0% (midazolam).
- Hypotension: 0% vs 5.0% (midazolam).
Behavioral recovery strongly favored dexmedetomidine:
- Agitation: 3% vs 16.7% with midazolam.
Midazolam required more sedation escalation:
- Rescue sedation: 7% vs 10.0% with dexmedetomidine.
Imaging success was high in both arms, with a slightly higher completion rate in the midazolam group (91.7%) than dexmedetomidine (83.3%), though dexmedetomidine required fewer rescue doses.
In this tertiary-care randomized trial in Lahore, dexmedetomidine provided superior recovery efficiency, earlier discharge readiness, markedly fewer respiratory complications, and substantially reduced agitation compared with midazolam for pediatric diagnostic imaging sedation. However, dexmedetomidine was associated with increased bradycardia and hypotension, emphasizing the need for structured monitoring and protocol-based cardiovascular management. Overall, dexmedetomidine appears to offer a more favorable balance of recovery quality and respiratory safety for pediatric imaging in tertiary hospitals when adequate monitoring is available.