Aim Dexmedetomidine is a selective central alpha-2 adrenergic receptor agonist. It induces sedation closely mimicking natural sleep, reduces anxiety and has sympatholytic effects – without having a clinically significant effect on respiratory function. Dexmedetomidine has a short half-life and quick onset of action, which have resulted in it being increasingly favoured on the unit over the cheaper first line alpha-2 adrenergic agonist clonidine. Our ‘Guidelines for Analgesia and Sedation in Children on the Paediatric Intensive Care Unit (PICU)’¹ were updated in 2020 to include guidance on the use of dexmedetomidine, including approved indications, for the first time. We aimed to assess compliance and efficacy of dexmedetomidine in hospitalised children on the PICU or Paediatric High Dependency Unit (PHDU) against indications and doses in our updated guidelines between September 2020 and May 2021:

• IV dexmedetomidine should be prescribed for one of the listed indications

• The dose of IV dexmedetomidine should not exceed 1.4 microgram/kg/hour

• The duration of IV dexmedetomidine should not exceed 72 hours

Method The audit was registered with the trust. Children prescribed IV dexmedetomidine on the PICU or PHDU were identified using the electronic prescribing system. Indication was identified using electronic medical notes. COMFORT scores were documented before and after dexmedetomidine initiation.² Education on the updated guidelines were provided before the data collection period and an update in January 2021 was delivered in the format of a monthly ‘DRUGgle’.

Results 33 patients with a median age of 2.2 years (range 2 months – 14.4 years) received IV dexmedetomidine. 32/33 prescriptions (97%) were as per the agreed indications. One patient (3%) was prescribed dexmedetomidine despite not having a trial of standard therapies. 18/32 (56%) of the courses for approved indications were to aid extubation, 12 (36%) for sedation in patients on non-invasive ventilation, and 2 patients (6%) received dexmedetomidine after prolonged use of standard therapies failed. In the 14 patients (total of 18 dexmedetomidine courses) for indications other than to aid extubation, COMFORT scores were recorded for 15 courses, but none had documented target scores. Patients remained or moved into a comfortable sedation score (12–17 COMFORT-B, 18–25 for COMFORT-Original) in 9 cases, 5 were slightly over sedated (10–11 COMFORT-B, 14–17 COMFORT-Original) and 1 infusion resulted in over sedation (<13 COMFORT-Original). IV dexmedetomidine did not exceed the maximum dose of 1.4 microgram/kg/hr in any of the patients identified. IV dexmedetomidine infusion was administered for more than 72 hours in 3 patients (9%): in two, a transition to clonidine was not attempted in a timely manner, in the third this was not successful due to labile blood pressure, bradycardia and restlessness. The main limitation was clarity on documented indications.

Conclusion Overall, compliance to approved indications for dexmedetomidine prescriptions was high; with 97% of all prescriptions as per updated guidelines. The dose never exceeded the recommended, but an infusion was administered for more than 72 hours in 9% of patients. COMFORT scores were maintained in comfortable range in almost all cases. A repeat audit will be carried out.

References

1. Royal Brompton and Harefield NHS Foundation Trust. Guidelines for Analgesia and Sedation in Children on the Paediatric Intensive Care Unit (PICU). 2020.

2. The Wellcome-Wolfson Institute for Experimental Medicine. SANDWICH – Sedation and Weaning in Children. COMFORT Original and COMFORT Behavioural Scores, 2018 [Online]. Available from: https://nicola.qub.ac.uk/sites/sandwich/SANDWICHQIBundle/COMFORT/COMFORTOriginalScore/HowtoInterpretaCOMFORTOScore/