By Dr Peter Kas at www.resus.com.au
A study in the NEJM (25th April 2015) by Moler et al. ‘Hypothermia in Out of Hospital Cardiac Arrest in Children’.
We know that hypothermia works in adults and more recently studies showed that we don’t need to cool patients to extremely low temperatures. In fact it is important to strictly control the temperature and not allow them to become febrile. Hypothermia in children has not been properly studied in cardiac arrest. What has been done has shown no benefit. In fact, work done on traumatic brain injured children and hypothermia showed a trend towards increased mortality (NEJM 2008; 358: 2447-2456).
This study looked at 411 children from ages 2 days old to 18 years old and patients were randomly assigned to therapeutic hypothermia or normothermia.
Inclusion criteria were patients that had a cardiac arrest requiring chest compressions for at least 2 minutes and who needed to remain on mechanical ventilation following return of spontaneous circulation.
Temperature management occurred for a total of 120 hours. The hypothermic group were kept at a core temperature of 33°c (32.0-34.0) for 48 hours then warmed to 36.8°c (36.0-37.5) for the remainder of the time to make up the 120 hours.
The outcome measured was good neurological outcome at 12 months. The proportion of survivors with good outcomes were: 20% in hypothermia vs 12% normothermia (p=0.14). There certainly was a trend towards better outcomes however these results were not statistically significant.
So at this time hypothermia in children out of hospital cardiac arrest confers no benefit over normothermia.