Timing of hypothermic temperature control does not affect neurological outcomes after cardiac arrest: a systematic review and meta-analysis

Authors: Krisztina Csőke-Kabai, Zsolt Molnár, László Zubek, Dávid Laczkó, Caner Turan, Péter Hegyi, Emőke Henrietta Kovács, Gábor Nagy, Sude Yilmaz, Zoltán Sipos & Krisztián Tánczos

This systematic review and meta-analysis included seven randomized controlled trials and 3,288 patients with out-of-hospital cardiac arrest, comparing prehospital with in-hospital initiation of hypothermic temperature control. Prehospital cooling achieved the target temperature of 33°C approximately 97 minutes earlier, but did not improve favourable neurological outcomes.

Prehospital cooling was associated with increased recurrent cardiac arrest and pulmonary oedema, particularly when large-volume intravenous fluids were used. The analysis found no survival benefit from earlier cooling, while evidence for fluid-sparing approaches such as transnasal evaporative cooling remained limited.