Dexmedetomidine sedation in a child with frontonasal encephalocoele scheduled for MRI

Abstract

Paediatric patients undergoing radiological imaging often require sedation to minimise motion artefacts. Sedation during Magnetic Resonance Imaging (MRI) poses many challenges to the anaesthetist. Inadequate or failed sedation results in difficulty in keeping them motionless while maintaining respiratory and hemodynamic stability. Secondly, limited access to the patient may pose a safety risk during MRI. Dexmedetomidine, an α2-adrenoceptor agonist, has recently been used as a sedative for diagnostic imaging studies. We report a use of dexmedetomidine for sedation in MRI suite in a child with frontonasal encephalocoele. A two-year-old girl child weighing 11 kg was scheduled for MRI of the brain and paranasal sinuses with nasal cavity under anaesthesia at our institute. After applying standard monitoring, an initial loading dose of dexmedetomidine was given @ 2 μg kg−1 over 10 min followed by continuous infusion of dexmedetomidine @ 1 μg kg−1 h−1. Sedation was monitored by the Ramsay Sedation Score (RSS), and as soon as a score of 5 was achieved, the child was transferred to the MRI table. Anaesthetic conditions were excellent, with minimal change in vital signs during the entire 35 min duration of the scan. Imaging was successful with no motion artefacts.