Advances in Cardiopulmonary Resuscitation: Hypothermia versus Normothermia in Survivors of Out-of-Hospital Cardiac Arrest

Abstract

Despite high levels of public awareness, the widespread use of automatic external defibrillators and the ongoing education of doctors in advanced life support seminars, the percentage of victims who arrive at the hospital after out-of-hospital cardiac arrest (OHCA) is small. Of those who reach the hospital, the main cause of death in two thirds of the cases is persistent neurologic disability. The only therapy that has so far seemed to positively affect the neurological outcome of patients after cardiac arrest is mild therapeutic hypothermia (MTH). However, the application of MTH is also known to be associated with a number of potential adverse effects, and recent trials report on an increasing rate of stent thrombosis. If the results are confirmed, safe levels of temperature regulation would need to be defined. Recently, a study was published that takes a critical approach to MTH. Hypothermia was compared to targeted temperature management near normothermia. After the end of the study period, there was no statistically significant difference regarding the survival to discharge and the neurological prognosis at 180 days. The authors stress that in both groups the temperature was actively controlled to avoid temperatures over 37 degrees Celsius. There followed few more publications with similar findings. The most important message from these trial is that even if the aggressive regulation of temperature with the form of hypothermia may seem unjustified, this does not mean that fever should be left untreated. Normothermia is a goal that can be achieved rather easily and can also save the lives of many patients.