Induced Hypothermia to 4.2°C with Neurologically Intact Survival: A Forgotten Case Series.

The lowest recorded core temperature from which a person with accidental hypothermia has survived neurologically intact is 11.8°C in a 2-y-old boy. The lowest recorded temperature from which an adult has been resuscitated neurologically intact is 13.7°C in a 29-y-old woman. The lowest core temperature with survival from induced hypothermia has been quoted as 9°C. We discovered a case series (n=50) from 1961 in which 5 patients with core temperatures below 11.8°C survived neurologically intact. The lowest core temperature in this group was 4.2°C. The authors also presented cardiovascular and other physiologic data at various core temperatures. The patients in the case series showed a wide variation in individual physiological responses to hypothermia. It is not known whether survival from accidental hypothermia is possible with a core temperature below 11.8°C, but this case series suggests that the lower limit for successful resuscitation may be far lower. We advise against using core temperature alone to decide whether a hypothermic patient in cardiac arrest has a chance of survival.

Approaches for Therapeutic Temperature Management.

In concert with an evolution toward an increased awareness of the need to tightly manage temperature, the methods used to monitor and manipulate temperature have evolved from mercury-filled glass thermometers, alcohol baths, and ice packs into a high technology-driven multidisciplinary activity. The purpose of this article is to provide a brief overview of the historical development of temperature management and the primary tenets of each of the 3 phases (induction, maintenance, and rewarming), which are now recognized as crucial steps to ensure the safe practice of therapeutic temperature management.