Stage
|
Clinical findings
|
Core temperature (°C) (if available)
|
---|
Hypothermia I (mild)
|
Conscious, shiveringa
|
35–32 °C
|
Hypothermia II (moderate)
|
Impaired consciousnessa; may or may not be shivering
|
<32–28 °C
|
Hypothermia III (severe)
|
Unconsciousa; vital signs present
|
<28 °C
|
Hypothermia IV (severe)
|
Apparent death; Vital signs absent
|
Variableb
|
-
aShivering and consciousness may be impaired by comorbid illness (i.e. trauma, CNS pathology, toxic ingestion, etc.) or drugs (i.e. sedatives, muscle relaxants, narcotics etc.) independent of core temperature
- The lowest temperature from which successful resuscitation and rewarming has been achieved is currently 13.7 °C [11] for accidental hypothermia and 9 °C for induced hypothermia [12]. This does not preclude resuscitation attempts at even lower temperatures if clinical judgment suggests the possibility of successful resuscitation
-
bThe risk of cardiac arrest increases below 32 °C, but as it is unlikely to be due solely to hypothermia until the temperature is <28 °C, alternative causes should be considered. Some patients still have vital signs <24 °C and the lowest reported temperature of a patient with vital signs is 17 °C [232, 233]