Effects of in-hospital low targeted temperature after out of hospital cardiac arrest: A systematic review with meta-analysis of randomized clinical trials

Objective: We performed this systematic review to evaluate the effectiveness of in-hospital low targeted temperature in adult patients after out of hospital cardiac arrest on survival and neurologic performance.

Data source: We systematically searched MEDLINE and PUBMED from inception to April 2014.

Study selection: Citations were screened for studies evaluating the effect of in-hospital low targeted temperature in patients following out of hospital cardiac arrest.

Data extraction: We analyzed randomized control trials (RCTs) that included adult patients resuscitated from out of hospital cardiac arrest, reporting mortality at hospital discharge and comparing in-hospital low targeted temperature with a control group.

Data synthesis: This meta-analysis included 6 RCTs and 1418 adult patients. In-hospital low targeted (low T) temperature was associated to a reduction in mortality at hospital discharge and at 6 months when compared with in-hospital targeted and not targeted temperature while there was no reduction in mortality comparing low and high targeted temperature. In patients with initial ventricular fibrillation/ventricular tachycardia rhythm of out of hospital cardiac arrest, low T was associated with a reduction in short and long-term mortality when compared with no targeted temperature while not when compared to high targeted temperature. Low T was associated with good neurologic performance at hospital discharge compared with in-hospital high or not targeted temperature.

Conclusion: In-hospital low targeted temperature (<4 °C) improved short and long-term mortality when compared to no targeted temperature. In contrast, low T did not improve outcome compared with a slightly higher targeted temperature (≈ 36 °C).