Intramuscular dexmedetomidine sedation for pediatric MRI and CT

Although dexmedetomidine has been administered to adults by intramuscular injection for perioperative anxiolysis and sedation, this route in children has not been described, to our knowledge. Our hypothesis was that intramuscular dexmedetomidine can be used to achieve sedation for MRI and CT of children.

The quality assurance data on all children who consecutively received intramuscular dexmedetomidine between August 1, 2007, and September 30, 2009, were reviewed. A single or repeated doses of 1-4 αg/kg intramuscular dexmedetomidine had been administered to achieve a minimum Ramsay sedation score of 4. Patient demographics, medical diagnosis, vital signs, adverse events, and outcome measures were reviewed.

Sixty-five children received consecutive intramuscular dexmedetomidine injections and successfully completed imaging studies. The MRI group received a total mean of 2.9 αg/kg dexmedetomidine, and the CT group received a mean of 2.4 αg/kg (p ≤ 0.01). There was no statistically significant relation between the total dose of dexmedetomidine received, mean time to achieve sedation (13.1-13.4 minutes), or time to meet discharge criteria after arrival in the recovery unit (17.1-21.9 minutes). Nine patients (14%) experienced hypotension, defined as a decrease in blood pressure to less than 20% of the age-adjusted awake normal value. The dosage of dexmedetomidine was not a predictor of hypotension. None of the patients had bradycardia, hypertension, or oxygen desaturation.

The intramuscular route is an alternative approach to dexmedetomidine delivery for pediatric sedation. Larger studies are warranted to evaluate the efficacy, safety, and hemodynamic outcome associated with the intramuscular use of dexmedetomidine in the care of children.