Using low doses of dexmedetomidine for procedural sedation during MRI diagnostics in children - case report

Introduction. Dexmedetomidine is a potent and highly selective ?2-adrenergic agonist. Its sedative effects are mediated through the inhibition of neuronal activity in the locus coeruleus, which is rich in ?2A-adrenergic receptors. In pediatric patients, sedation or general anesthesia is often required for certain diagnostic procedures, such as magnetic resonance imaging, due to limited cooperation in children under six years of age and the intense noise during scanning, ensuring patient tolerance and procedural success. Case Report. We present the case of a five-yearold boy referred for magnetic resonance imaging due to headaches and dizziness. Premedication was administered intramuscularly 30 minutes before the procedure, consisting of atropine (0.0125 mg/kg) and midazolam (0.1 mg/kg). Simultaneously, an initial intravenous bolus of dexmedetomidine (2 ?g/kg) was infused over 15 minutes. The child was then transferred to the magnetic resonance imaging room, where sedation was maintained with a continuous intravenous infusion of dexmedetomidine at 0.25 ?g/kg/h via an infusion pump, without additional anesthetic agents or bolus doses. No adverse effects, including bradycardia, respiratory disturbances, or desaturation were observed. Conclusion. Despite the use of a subminimal continuous dexmedetomidine dose compared to recommended dosing regimens, an adequate depth of sedation was achieved, allowing for high-quality magnetic resonance imaging without complications.