Date Published: March 9, 2017
Publisher: Public Library of Science
Author(s): Aurélie Sellam, Noëlla Lode, Azzedine Ayachi, Gilles Jourdain, Stéphane Dauger, Peter Jones, Umberto Simeoni.
Hypothermia initiated in the first six hours of life in term infants with hypoxic ischemic encephalopathy reduces the risk of death and severe neurological sequelae. Our study’s principal objective was to evaluate transport predictors potentially influencing arrival in NICU (Neonatal Intensive Care Unit) at a temperature ≥35-<36°C. A multi-centric, prospective cohort study was conducted during 18 months by the three Neonatal Transport Teams and 13 NICUs. Newborns were selected for inclusion according to biological and clinical criteria before transport using passive hypothermia using a target temperature of ≥35-<36°C. Data on 120 of 126 inclusions were available for analysis. Thirty-three percent of the children arrived in NICU with the target temperature of ≥35-<36°C. The mean temperature for the whole group of infants on arrival in NICU was 35.4°C (34.3–36.5). The median age of all infants on arrival in NICU was 3h03min [2h25min-3h56min]. Three infants arrived in NICU with a temperature of <33°C and eleven with a temperature ≥37°C. Adrenaline during resuscitation was associated with a lower mean temperature on arrival in NICU. Our strategy using ≥35-<36°C passive hypothermia combined with short transport times had little effect on temperature after the arrival of Neonatal Transport Team although did reduce numbers of infants arriving in NICU in deep hypothermia. For those infants where hypothermia was discontinued in NICU our strategy facilitated re-warming. Re-adjustment to a lower target temperature to ≥34.5-<35.5°C may reduce the proportion of infants with high/normothermic temperatures.
Hypoxic-ischaemic encephalopathy (HIE) of term new-borns is an important cause of death and neurological disability [1–3]. The frequency of HIE is approximately two to three newborns for every 1000 live births.
The study was approved by the local IRB (Comité d’Evaluation d’Ethique en Recherche Biomédicale of the Hôpital Robert Debré) and data recording and processing by the Commission Nationale de l’Informatique et des Libertés. An information letter was provided for parents detailing the inclusion and allowing for the possibility of removal of their child from the study. Consent was not requested. All ethical procedures strictly complied to French law and were approved by the IRB.
One hundred and twenty-six infants were eligible for inclusion. Five infants were not included and one was excluded for a temperature of 23°C on arrival of the NNT Team; the inclusions and exclusions are shown in Fig 1 and population characteristics are illustrated in Table 1. Forty-four (37%) inclusions were made by the NNT Team of the Hôpital Robert Debré, 41 (34%) by Hôpital André Gregoire and 35 (29%) by Hôpital Antoine Béclère. Forty-five percent were transferred from type 2a maternity units, 18% from type 2b, 30% from type 1 and 8% between type 3. There were no statistical differences in the population characteristics between the three groups (Table 1).
Thirty-three percent of infants arrived in NICU with the target temperature of ≥35-<36°C. The use of adrenaline during resuscitation predicted with a lower arrival temperature. There was a tendency for the infants with higher APGAR scores at 10 minutes or maternal pyrexia to have a higher NICU arrival temperature. Our strategy using ≥35-<36°C passive hypothermia combined with short transport times reduced the risk of the infants arriving in NICU in deep hypothermia. The use a target temperature of ≥35-<36°C would be inappropriate in areas where transport times mean that true hypothermia cannot be achieved within the six hour therapeutic window. For those infants where hypothermia was discontinued on arrival in NICU, our strategy facilitates re-warming. Refinement is needed to increase cooling in cases of maternal pyrexia. The use of adrenaline during resuscitation was an independent predictor of lower body temperature. A re-adjustment of the target temperature to ≥34.5-<35.5°C may reduce the proportion of infants arriving in NICU with high temperatures. Source: http://doi.org/10.1371/journal.pone.0170100