Case Study 33

The Answer


  • Possible severe hypothermia
  • Partial and full thickness frostbite to fingers, toes, nose, ears, abdomen

The Plan

  • The patient has been placed dry in a sleeping bag which has been wrapped in two additional sleeping bags and a sheet of plastic. External heat is being applied with forced warm air system. O2 by cannula at 6 l/m to conserve a limited supply.
  • Air evacuation is not available. Patient will be driven in SAR SUV toward pavement for EMS rendezvous. ALS providers are en route to rendezvous with SAR.
  • The frostbite is not being treated at this time.

Anticipated Problems

  • Cardiac arrest due to cardiovascular instability from the hypothermia.


Mild hypothermia can often be managed in the field. We change the patient’s environment and make sure they are dry, insulated ,and wind-proofed. We add calories to fuel shivering, their best source of heat. We may use hot water bottles and a hypothermia wrap for warmth and insulation. For the alert and ambulatory patient exercise can be a helpful source of heat production. Treatment of severe hypothermia is another story altogether.

At the time of this rescue, three decades ago, there was a concept in the management of severe hypothermia known as the “metabolic icebox.” It was a presumption that a profoundly cold patient was stable and should not have external heat applied in the field due to risk of causing “rewarming shock” and cardiac arrhythmias.

However, the rescuers decided that this patient was likely dehydrated and depleted of energy reserves, his metabolic fires dampened, and would only become colder if they did not apply heat. This is consistent with current understanding that it is unlikely that field warming can be aggressive enough to trigger these treatment complications and application of warmth to stabilize the patient’s temperature is helpful.

They first tried a portable heating device, but this malfunctioned. Hot water bottles seemed weak tools. A creative solution was to use a dryer hose taped to a heat duct in the vehicle to direct warm air into the sleeping bag. Whether this helped stabilize his temperature is unknown. What is known is that upon arrival in the emergency room the patient’s rectal temperature was 75°F, he was still breathing on his own, and he had a slow but stable heart rhythm.

Treatment Principles: Severe Hypothermia

Field warming is unrealistic. The goal of treatment is temperature stabilization, life support, and transport.

Handle gently, and strive to keep the patient horizontal.

  • Rough movement and vertical position is associated with (but not proven to cause) post-rescue collapse in cold patients.

Administer warm, humidified oxygen, if available.

  • Warm, humid air does not provide a lot of warming, but it prevents respiratory heat and moisture loss.

Prevent further heat loss. Package in hypothermia wrap.

  • Dry insulation and a wind and vapor barrier help capture whatever heat the patient is producing, and whatever external heat the rescuer has added to the system.

Add heat packs or hot water bottles. Insulate these to prevent burns. Focus on the axilla and chest.

  • A cold patient may not perceive when they are being burned. Axilla and chest placement focus this heat on the vital core.

Avoid walking or standing. Do not use exercise to produce heat.

  • The advice to “feed em and beat em” only applies, at best, for alert and ambulatory patients. We agree with the feeding part for a patient who is alert, not the beating part.

Assist breathing for 5–15 minutes prior to movement.

  • This is thought (but not proven) to help stabilize a cold heart.

Avoid the chest compressions involved in CPR unless the absence of a pulse is confirmed.

CPR in a hypothermic patient may be extended past the 30-minute guideline.

End of the Tale

Transport was slow to avoid bouncing the patient. No change in the patient’s condition was seen during transport. Rendezvous with ALS provided a cardiac monitor which showed a heart rate of 30 with occasional ectopic beats. Respiratory rate was again assessed as 6. It was decided that no other ALS intervention (intubation, IV, medication) was warranted or wise.

The time from being found to arrival in the cabin was approximately 30 minutes. Assessment and initial treatment in the cabin while transport options were resolved was another 30 minutes. Ground transport to a EMS unit was 60 minutes. The patient arrived in the emergency department 2.5 hours after he was found. He experienced a cardiac arrest at that time, surviving this new challenge after three hours of chest compressions and aggressive hospital warming raised his temperature to the point where defibrillation was successful. He suffered extensive tissue loss from the frostbite. It is believed that after he recovered he moved to southern Texas.