Therapeutic hypothermia after cardiac arrest: where are we now?

Therapeutic hypothermia is widely recommended after cardiac arrest. In this review, we present publications reflecting the current discussion and opinions related to use of therapeutic hypothermia in comatose adult cardiac arrest survivors.

The clinical outcome benefit of therapeutic hypothermia found in recent effectiveness studies is similar to that found in previous randomized trials. No single cooling method has been shown to be superior in terms of clinical outcomes. Therapeutic hypothermia is easy to perform and lacks severe side-effects or complications associated with mortality. Prehospital and intra-arrest cooling are being explored as a way to further improve outcome, although no clear relationship between timing of cooling and outcome has been documented.

Although only proven beneficial for patients with ventricular fibrillation, the majority of centres today use therapeutic hypothermia also for comatose survivors with other initial rhythms. Some controversies still exist; the optimal target temperature, timing and duration of cooling have not yet been defined, and some researchers still think that the concept of therapeutic hypothermia is not satisfactorily proven scientifically. A new randomized study comparing temperature management to 36°C with 33°C is therefore underway.