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Hypocapnia in early hours of life is associated with brain injury in moderate to severe neonatal encephalopathy

Journal of Perinatology volume 42, pages 892–897 (2022)Cite this article

Subjects

Abstract

Objective

To evaluate the association between hypocapnia within the first 24 h of life and brain injury assessed by a detailed MRI scoring system in infants receiving therapeutic hypothermia (TH) for neonatal encephalopathy (NE) stratified by the stage of NE.

Study design

This retrospective cohort study included infants who received TH for mild to severe NE.

Results

188 infants were included in the study with 48% having mild and 52% moderate-severe NE. Infants with moderate-severe NE spent more time in hypocapnia (PCO2 ≤ 35 mmHg) and presented with more severe brain injury on MRI compared to mild cases. The MRI injury score increased by 6% for each extra hour spent in hypocapnic range in infants with moderate-severe NE. There was no association between hypocapnia and injury scores in mild cases.

Conclusion

In infants with moderate-severe NE, the hours spent in hypocapnia was an independent predictor of brain injury.

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Fig. 1: Prediction of brain injury score based on hours spent in hypocapnia.

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Acknowledgements

We thank our statistician, Laszlo Szakacs, for his expert help with data management and analysis.

Author information

Authors and Affiliations

  1. Department of Pediatric Newborn Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, United States

    Eniko Szakmar, Chelsea Munster, Hoda El-Shibiny, Terrie Inder & Mohamed El-Dib

  2. 1st Department of Pediatrics, Semmelweis University, Budapest, Hungary

    Eniko Szakmar & Agnes Jermendy

Authors
  1. Eniko Szakmar
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  2. Chelsea Munster
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  3. Hoda El-Shibiny
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  4. Agnes Jermendy
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  5. Terrie Inder
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  6. Mohamed El-Dib
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Contributions

ESz had substantial contributions to conception and design, data analysis, and interpretation of data. She also drafted the article and had final approval of the version to be published. CM and HE helped to collect and analyze the data and to write the manuscript draft. AJ and TI had substantial contributions to conception and interpretation of data, and revised the manuscript for important intellectual content. ME conceptualized and designed the study, supervised all aspects and critically reviewed the manuscript. All authors approved the final manuscript as submitted and agree to be accountable for all aspects of the work.

Corresponding author

Correspondence to Mohamed El-Dib.

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Competing interests

The authors declare no competing interests.

Ethics approval and consent to participate

This study was approved by the Partners Human Research Committee Institutional Review Board and consent was waived (IRB protocol# 2014P002430).

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Szakmar, E., Munster, C., El-Shibiny, H. et al. Hypocapnia in early hours of life is associated with brain injury in moderate to severe neonatal encephalopathy. J Perinatol 42, 892–897 (2022). https://doi.org/10.1038/s41372-022-01398-2

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