Nouvelles problématiques liées à l'hypothermie thérapeutique après arrêt cardiaque

Mild therapeutic hypothermia (32-34 °C) has been recently introduced into the international guidelines of cardiac arrest management, considering that the patient survival without neurological sequellae for out-of-hospital cardiac arrests following ventricular fibrillation has been improved with induced and controlled hypothermia. The benefit of therapeutic hypothermia is largely related to its neuroprotective effects. However, several issues remain unsolved to date. Consistently, the therapeutic window for applying hypothermia and the exact mechanism of the hypothermia effects on the ischemia-reperfusion syndrome and the cerebral anoxia are only partially understood. Furthermore, this efficient treatment is associated with some side effects that could counterbalance its benefits. Although recommended by all international committees, the exact implementation modalities of hypothermia still remain to be clarified, including the patient-to-treat selection criteria, the most efficient cooling and rewarming devices, the cooling duration and depth, the optimal temperature monitoring, and the usefulness of the associated treatments. Beneficial or deleterious extraneurological hypothermia effects, mainly regarding the cardiovascular and the respiratory systems, have also not been yet completely elucidated. Taking into accounts its risk-benefit balance and treating its potential complications should enhance hypothermia benefits. Only a better understanding of its precise effects and its optimal implementation modalities would be helpful in order to improve the final cardiac arrest prognosis.