RecruitingDrug trialDex +/- Caffeine Sedation in a Post-MRI Recovery in a Pediatric PopulationDexmedetomidine (Dex), a selective α2-adrenergic receptor agonist, is the most used sedative for procedural sedation in children and in pediatric Intensive Care Unit (PICU) because it is associated with less respiratory depression and also less neurotoxicity; rather Dex appears neuroprotective. Unfortunately, Dex is associated with very long emergence times and may cause bradycardia and hypotension. However, using sedation dosing guidelines (by consensus among SPS members) 1-3 mcg/kg bolus and a 1-2 mcg/kg/hour infusion, hemodynamic compromise is less significant and rarely requires intervention in these patients. With this Dex sedation protocol, these pediatric patients usually take an average of 45 minutes (30-60 minutes) to wake and become alert and up to 2 hours to be discharged. Without reversal agents, emergence times from Dex sedation are slow. The prolonged recovery after Dex sedation for non-surgical procedures negatively affects throughput, thus increasing the cost of care. Patient safety and satisfaction suffer as a result. The children wake feeling tired and sluggish. The children don't feel back to normal for an extended period of time, which is not surprising given that the half-life for Dex metabolism in 2-3 hours in humans. However, using sedation dosing guidelines (by consensus among SPS members) 1-3 mcg/kg bolus and a 1-2 mcg/kg/hour infusion, hemodynamic compromise is less significant and rarely requires intervention in these patients. In humans, it has been found that caffeine at 7.5 mg/kg (15 mg caffeine citrate equivalent to 7.5 mg caffeine base) sped emergence from isoflurane anesthesia with minimal hemodynamic effects in healthy human volunteers. The goal of this clinical trial is to determine whether caffeine will facilitate the recovery of Dex sedation after a Magnetic Resonance Imaging (MRI) procedure by measuring the time from the end of Dex infusion to the time meeting the discharge criteria.