The widespread use of hypothermia for treatment of brain injury was ushered in after two major studies published in NEJM in 2002. The history of hypothermia goes back even further and was proposed as a potential treatment by the pioneers of resuscitation science in the 1960s.
Despite widespread use of temperature management and some supporting animal data, the quality of evidedence for hypothermia in cardiac arrest is low, and in addition much remains to be learned about the best way to apply temperature managment. The TTM-group published a systematic review in 2011 which showed that studies performed up until then were at a high risk of bias.
The TTM1-trial was therefore designed to compare a target temperature of 33°C to 36°C. This trial, published in 2013, showed that the lower target temperature did not confer a survival benefit.
In addition to the TTM-project, the researchers involved have also worked on the international cardiac arrest registry (INTCAR) to gather information on how temperature management is applied outside of RCTs.