Targeted Temperature Management in Postresuscitation Care After Incorporating Results of the TTM2 Trial.

ABSTRACT

Cardiac arrest still accounts for a substantial proportion of cardiovascular related deaths and is associated with a tremendous risk of neurological injury and, among the few survivors, poor quality of life. Critical determinants of survival and long-term functional status after cardiac arrest are timely initiation of cardiopulmonary resuscitation and use of an external defibrillator for patients with a shockable rhythm. Outcomes are still far from satisfactory, despite ongoing efforts to improve cardiac arrest response systems, as well as elaborate postresuscitation algorithms. Targeted temperature management at the wide range between 32 °C and 36 °C has been one of the main therapeutic strategies to improve neurological outcome in postresuscitation care. This recommendation has been mainly based on 2 small randomized trials that were published 20 years ago. Most recent data derived from the TTM2 (Targeted Hypothermia Versus Targeted Normothermia After Out-of-Hospital Cardiac Arrest) trial, which included 1861 patients, challenge this strategy. It showed no benefit of targeted hypothermia at 33 °C over normothermia at 36 °C to 37.5 °C with fever prevention. Because temperature management at lower temperatures also correlated with an increased risk of side effects without any benefit in the TTM2 trial, a modification of the guidelines with harmonizing temperature management to normothermia might be necessary.