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Hypothermic treatment for neonatal asphyxia in low-resource settings using phase-changing material-An easy to use and
Hang T T Tran1,2,3, Ha T T Le1, Hanh T P Tran1
1Neonatal Intensive Care Unit, Vietnam National Children's Hospital (VNCH), Hanoi, Vietnam.
Aim:
To evaluate whether phase-changing material can be used for therapeutic hypothermia of asphyxiated newborns in low-resource settings.
Methods:
Prospective interventional study of asphyxiated term infants fulfilling criteria for hypothermia treatment at Vietnam National Children's Hospital from September 2014 to September 2016. Hypothermia was induced within 6 hours after birth and maintained for 72 hours by a phase-changing material mattress with melting point of 32°C. Rectal temperature was continuously measured, and deviations from target temperature range 33.5-34.5°C were recorded.
Results:
In total 52 infants (mean gestational age 39.3 ± 1.1 weeks) included and cooled, the median temperature at initiation of cooling was 35.3 (IQR 34.5-35.9)°C. The median time to reach target temperature was 2.5 (IQR 2-3) hours. The mean temperature during the cooling phase was 33.95 ± 0.2°C. Throughout the cooling phase, the target temperature range (33.5-34.5°C) was maintained more than 80% of the time. Rate of rewarming was 0.5 ± 0.14°C/hour.
Conclusion:
Phase-changing material can be used as an effective cooling method. Though not a servo-controlled system, it is easy to induce hypothermia, maintain target temperature and rewarm infants in a slow and controlled manner without need for frequent changes and minimum risk of skin injury.
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