Targeted temperature management (TTM, therapeutic hypothermia) after cardiac arrest first came to use in clinical setting since the publication of two landmark articles in 2002. Evidence was mainly for out of hsopital cardiac arrest patients. Recently, it was noted that there was no difference in outcome between temperatures of 33 and 36 Celsius.
However, based on the evidence, same therapuetic modality was offered to in hospital cardiac arrest patients in various hospitals and countries. Latest in the series were Canadian guidelines which recommended TTM for in hospital cardiac arrest.
Paul Chan et el published a study in JAMA on Oct 4, 2016 about effect of therapuetic hypothermia on in hospital cardiac arrest.
In this cohort study, they looked at 1568 patients who were resuscitated from in hospital cardiac arrest, and then received TTM. These are patients from national Get With the Guidelines–Resuscitation registry from 2002 to 2014 from various US hospitals.
What they found was that use of TTM was associated with lower likelihood of survival(27.4% vs 29.2%; relative risk [RR], 0.88 [95% CI, 0.80 to 0.97]) to hospital discharge and a lower likelihood of favorable neurological survival.
A randomized trial is required to further rest the matter. Meanwhile, do not cool for in hospital cardiac arrest.
1. Bernard SA, Gray TW, Buist MD, et al. Treatment of comatose survivors of out-of-hospital cardiac arrest with induced hypothermia. N Engl J Med 2002;346:557–63.
2. Hypothermia after Cardiac Arrest Study Group. Mild therapeutic hypothermia to improve the neurologic outcome after cardiac arrest. N Engl J Med 2002;346:549–56
3. Nielsen N, Wetterslev J, Friberg H, TTM Trial Steering Group. Targeted temperature management after cardiac arrest. N Engl J Med 2014;370:1360
4. Canadian guidelines for TTM https://dx.doi.org/10.1016/j.resuscitation.2015.07.052