Determining the Effect of Birth Weight on Therapeutic Hypothermia in Neonates with Hypoxic-Ischemic Encephalopathy

Abstract

Objective We examine the effect of birth weight (BW) for gestational age (GA) on the temperatures reached during the treatment of neonatal hypoxic-ischemic encephalopathy (HIE) with therapeutic hypothermia (TH).

Study Design Retrospective data of 1,736 neonates with HIE who received TH were extracted from the Canadian Neonatal Network database for neonates admitted from 2010 to 2017. Neonates were stratified into three BW groups: small for GA < 10th centile, large for GA > 90th centile, and according to GA 10th to 89th centile at a given gestation using Canadian population data norms.

Results There was no significant difference in the lowest temperature reached, the likelihood of overshooting temperatures < 32.5°C during TH, or the change of encephalopathy stages among the three groups.

Conclusion BW for GA did not appear to influence the temperatures neonates reached during hypothermia or encephalopathy stage following TH.

Key Point

• Therapeutic hypothermia is well tolerated irrespective of weight for age

• SGA infants achieved and maintained target temperature similar to AGA and LGA babies

• Change in the Sarnat stage after hypothermia was similar across all birth weight groups

Keywords

hypoxic-ischemic encephalopathy - therapeutic hypothermia - neonates - birth weight

Note

This is an original article that has not been previously published or submitted for publishing elsewhere while under consideration. This article is relevant to the Journal of Perinatology as it relates to an important and unanswered aspect of the effectiveness of therapeutic hypothermia, the only available and effective treatment for hypoxic-ischemic encephalopathy. In this original research, we examined the effect of birth weight on the effectiveness of therapeutic hypothermia in infants admitted to the Canadian neonatal intensive care units.

Ethical Approval

Ethical approval was obtained from Kingston Health Sciences ethics office. Ethics was also obtained from individual institutions by the Canadian Neonatal Network. The study was performed in accordance with the Declaration of Helsinki.

Authors' Contribution

M.G. wrote the manuscript. P.S. contributed to the manuscript. F.K. contributed to the manuscript as senior author. CNN completed the statistics and data extraction.

^* This is to refer the list of investigator who are part of this network.

Publication History

Received: 14 October 2021

Accepted: 25 December 2021

Article published online:
14 February 2022

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