Emergency Medical Services

BATEYMatt Batey
95 River Valley Dr.
Hartsville, Tennessee 37074

Phone: (615)374-9503
Email:  Matthew.Batey@trousdalecountytn.gov



Hypothermia describes a state in which the body's ability for temperature regulation is overwhelmed by the cold.

Accidental hypothermia generally results from exposure by inadequately prepared person; examples include inadequate shelter for a homeless person, someone caught in a winter storm or motor vehicle accident, or an outdoor sport enthusiast caught off guard by the elements, such as hunters.  Many patients have recovered from severe hypothermia, so early recognition and prompt activation of 911 is paramount.

Mild hypothermia (89-95°F)

  • Between 93°F and 95°F, most people shiver vigorously, usually in all extremities.
  • As the temperature drops below 93°F, a patient may develop altered judgment, amnesia, and difficulty speaking. Respiratory rate may increase.
  • At approximately 91°F, un-coordination and apathy may be seen. Patients generally are stable and able to compensate for the symptoms.
  • In this temperature range, the following may also be observed: hyperventilation, rapid breathing, and increased heart rate.
Moderate hypothermia (82-89°F)

  • Oxygen consumption decreases, and the central nervous system becomes depressed; shallow breathing, and undressing even in a cold environment may be noted.
  • Most patients with temperatures of 89°F or lower present in a near unconsciousness.
  • As the core reaches temperatures of 87°F or below, the body loses its ability to generate heat by shivering
  • At 86°F, patients develop a higher risk for abnormal heart rhythms. The pulse continues to slow progressively, and cardiac output is reduced.
  • Between 82°F and 86°F, pupils may become dilated and minimally responsive to light, a condition that can mimic brain death.
Severe hypothermia (< 82°F)

  • At 82°F, the body becomes very susceptible to ventricular fibrillation (cardiac arrest) and decreased blood flow from the heart.
  • Below 80°F, 83% of patients are comatose.
  • Prehospital management focuses on preventing further heat loss, rewarming the body.  Conscious patients can develop ventricular fibrillation (cardiac arrest) suddenly; EMS workers should avoid inadvertent jerky movement of severely hypothermic patients.
To prevent cardiac dysrhythmia with continued hypothermia, rescuers or paramedics should attempt rewarming in the field. (A notable exception would be isolated frostbite injury in which limb rewarming would can cause significant pain.) Note the following:

  • Remove patient from cold environment.
  • Remove wet clothing, and replace it with dry blankets or sleeping bags.
  • Initiate active external rewarming with heat packs (e.g., hot water bottles, chemical packs) placed in the axillae, on the groin, and on the abdomen.
  • Be aware of the risk of causing body surface burns from rewarming.
If you see someone who has fallen in cold water, do not enter the water to rescue them, if you can reach them with something and pull them to safety or throw them a rope.  If not wait for trained first responders with proper rescue equipment.