Table 4.

Clinical studies of use of dexmedetomidine in infants undergoing therapeutic hypothermia for HIE

Study ID setting	Study design	Inclusion criteria	Dexmedetomidine group	Comparator	Outcomes notes
O’Mara 2018 USA Single centre35	Retrospective cohort study July 2013 to October 2016	HIE requiring TH Received dexmedetomidine for 48 hours	N=19 2, dexmedetomidine only; 17, combination with fentanyl	No comparator	Fentanyl weaned down in 13/17 after starting dexmedetomidine 10 infants required inotropes. Initiation of dexmedetomidine did not affect HR, or BP. One infant had bradycardia – resolved with discontinuation of fentanyl Clinical outcomes: 1 died; 8 had seizures
Cosnahan 2021 USA single centre19	Retrospective cohort study January 2018 to April 2020	HIE requiring TH (NICHD criteria)	March 2019-April 2020 N=34 Continuous dexmedetomidine 0.3 μg/kg/hour with increments of 0.1 μg/kg/hour based on pain scores and breakthrough morphine dose requirements Maximum: 2 μg/kg/hour	January 2018-March 2019 N=36 Intermittent morphine 0.1 mg/kg every 4 hours	No difference in N-PASS scores Dexmedetomidine group had: Higher breakthrough morphine requirement: 0.13 (0.13) vs 0.04 (0.09) mg/kg, p=0.001 Lower total morphine requirement: 0.13 (0.13) vs 1.79 (0.23) mg/kg, p<0.0001 Reduced respiratory support requirement Similar outcomes for feeding, EEG and MRI scan All HR measurement in normal range morphine group had higher HR and BP at some timepoints
Elliot 2022 abstract only USA Single centre34	Retrospective cohort 2011–2019	Dexmedetomidine and/or fentanyl	Dexmededetomidine=46 (14 monotherapy; 32 in combination)	Fentanyl=120	Dexmedetomidine group had lower HR: 91±9 vs 103±11 bpm Dexmedetomidine was reduced or discontinued in 22 (48%) due to inadequate sedation with low HR

BP, blood pressure; HIE, hypoxic ischaemic encephalopathy; HR, heart rate; N-PASS, Neonatal Pain and Sedation Scale; TH, therapeutic hypothermia.