Severe hypothermia is defined as a core body temp of less than 86 degrees Fahrenheit. the victim's level of consciousness is a good indicator of how severe the hypothermia is. In early stages, a victim can feel excited, with lots of shivering and increased metabolic rate. later stages involve progressive slowing of body functions and decreased level of consciousness.
There are some conflicts in the literature, but general guidelines for severe hypothermia without signs of life are:
1. Carefully assess for breathing and pulse for 30 seconds.
2. Call for help.
3. If the victim has a pulse, perform rescue breathing if there are no respirations detected. Use warm O2 (108-115F) ventilation, if possible., and ventilate at half the usual rate per minute.
3. If no pulse-begin CPR, starting with compressions.
4. If there is an AED available, attach it and analyze the rhythm.
If the core temperature is known to be below 86F, give ONE shock if the AED instructs you to. No further shocks are generally recommended until the core temperature rises above 86F.
If the victim's temperature known to be 86F or above, typical BLS and ACLS interventions should be followed.
Follow all of the modified BLS guidelines, including a single defibrillation attempt while the core temperature remains below 86 degrees Fahrenheit.
Intubate the patient to facilitate the use of warm O2 (108-115F) during ventilation, if available. Ventilate at half the usual rate per minute.
If the temperature is known to be below 86F, medications should generally be held until core temp. is 86 or higher, although AHA guidelines recommend up to 3 doses of epinephrine. Again, if the temperature is known to be 86F or above, no modifications to typical interventions are required.
ACLS management of hypothermic arrest focuses on aggressive rewarming techniques as the primary treatment. The cold heart is theoretically unresponsive to drugs, and defibrillation; therefore drug metabolism may be reduced, and medications could accumulate to toxic levels in the peripheral circulation if given repeatedly - the ideas to support this are theoretical.
Treatment of pre-arrest hypothermia is covered in AHA's First Aid course.
Hypothermia and refractory cardiac arrest are covered in ACLS under the H's and T's.
Inducing Therapeutic Hypothermia in a post- cardiac arrest victim is a fundamentally different topic, and can be found here: http://www.carpentercprsolutions.com/-blog/post-arrest-hypothermia