# Implementation of active therapeutic hypothermia across a regional transport network for infants transferred for neonatal encephalopathy

## TL;DR

This study shows that using active cooling during transport and at referring hospitals helps infants with brain injury reach the right temperature faster and improves outcomes.

## Contribution

The study demonstrates that implementing active therapeutic hypothermia in transport and referring centers improves temperature management for infants with HIE.

## Key findings

- Active cooling during transport reduced time to reach target temperature by 73 minutes compared to passive cooling.
- Initiating active cooling at referring centers further reduced time to target temperature by 89 minutes.
- More infants achieved target temperature within 6 hours with active cooling, and fewer were overcooled.

## Abstract

The aim of this study was to evaluate the introduction of servo-controlled therapeutic hypothermia (TH) by a regional transport service and referring centres for infants with hypoxic ischaemic encephalopathy (HIE). The primary objective was to compare the time to reach 33–34 °C target temperature (TT).

This is a retrospective cohort study of neonatal transfers for TH across a large UK regional network from 2011 to 2021. Three cohorts were identified for comparison, defined by the setting of TH initiation: referring ‘Base’ centre or during ‘Transport’ and by the TH method: passive(Pass) or active(Act).

A total of 315 infants were included. The TransportAct (n = 128) cohort achieved TT significantly earlier (280 min) than the TransportPass (n = 155) cohort (353 min, P < 0.001), with 84% vs 46% (OR 6.3, 95% Cl 3.3–11.8, P < 0.0001) achieving this within 6 h of birth. Introduction of BaseAct (n = 32) was associated with an additional 89 min reduction in time to TT (191 min, P < 0.0001), with more infants achieving this within 3 h (44% vs 19%; OR 3.3, 95% Cl 1.4–7.7, P < 0.01), and a shorter stabilisation time (110 vs 175 min, P < 0.001). Outcomes for infants were not different.

Compared with passive cooling, the introduction of transport and referring centre active TH improves temperature management of transferred infants with HIE, with more reaching therapeutic temperature within 6 h and fewer being overcooled.

Early therapeutic hypothermia (TH) improves survival without disability for infants with hypoxic ischaemic encephalopathy (HIE). However, many infants are born in centres without servo-controlled TH and rely on passive cooling prior to transfer.

Early therapeutic hypothermia (TH) improves survival without disability for infants with hypoxic ischaemic encephalopathy (HIE). However, many infants are born in centres without servo-controlled TH and rely on passive cooling prior to transfer.

This study demonstrates that the introduction of active TH by both the transport team and by referring centres is associated with significant improvements in time to reach target temperature, minimising overcooling and reducing transport stabilisation times.Investment in active TH provision by all birth centres and transport teams could be a cost-effective method to reduce birth-related brain injury and improve outcomes of infants with HIE.

This study demonstrates that the introduction of active TH by both the transport team and by referring centres is associated with significant improvements in time to reach target temperature, minimising overcooling and reducing transport stabilisation times.

Investment in active TH provision by all birth centres and transport teams could be a cost-effective method to reduce birth-related brain injury and improve outcomes of infants with HIE.