Cold-Weather Emergencies: Hypothermia & Frostbite

"Engine 25 respond to an unconscious person located under the railroad bridge. Cross street is West Ox Road. Weather reports continue to indicate a wind chill of minus 17 degrees"

When the body temperature falls into the subnormal area (below about 95 degrees Fahrenheit), the condition is called hypothermia (low temperature). Hypothermia occurs when a person's body is not able to produce enough energy to keep the internal (core) body temperature at a satisfactory level.

Photo by Adam Alberti
Cold weather presents special hazards, including hypothermia (subnormal body temperature) and frostbite, that require prompt action by first responders.

Hypothermia is not only a winter problem, for it can occur in temperatures as high as 50 degrees F (10 degrees Celsius). People who become cold because of inadequate or wet clothing are susceptible to hypothermia, especially if they are weakened by illness.

The signs of hypothermia include feelings of being cold, shivering and sleepiness. Shivering is the body's way of trying to produce more heat. As hypothermia progresses, shivering stops. A patient who cannot even shiver cools down even faster than before.

Signs of increasing hypothermia include a lack of coordination, mental confusion, and slowed reactions. If the patient is not treated and rewarmed, unconsciousness will result. Unconsciousness occurs when the patient's body temperature goes below about 90 degrees F (32 degrees C). If not reversed by rewarming, the downward spiral continues until death occurs.

If you suspect that a patient is suffering from hypothermia, move the patient to a warm (or warmer) location. Remove wet clothing and place warm blankets over and under the patient. Doing this helps to retain body heat and begins the rewarming process. If the patient is conscious, give warm fluids to drink. If you cannot easily take the patient inside a building, move the patient into a heated vehicle as soon as possible.

If the patient's temperature falls even lower (to about 83 degrees F), the heart may stop and you will need to start CPR. Any patient suffering from hypothermia must be examined by a physician.

Cardiac arrest and hypothermia. In some cases, hypothermia may protect patients from death. Therefore, always start CPR on hypothermic patients even if you believe they may have been "dead" for several hours.

Hypothermic patients should never be considered dead until they have been rewarmed in an appropriate medical facility. An excellent example of this principle is a child who has fallen into cold water and apparently drowned. Many such children have been resuscitated successfully. Always start CPR on these patients.

Frostbite. Frostbite can result when exposed parts of the body are in a cold environment. It can occur outdoors in the winter or even in a walk-in food freezer or cold-storage warehouse in the middle of the summer. Exposed body parts actually freeze.

The body parts most susceptible to frostbite are the face, ears, fingers, and toes. Depending on the temperature and wind velocity, frostbite can occur in even a short period of time.

Increases in wind speed have the same effect as decreases in temperature. Think about holding your hand outside an automobile traveling at 55 mph on a cold winter day! The combination of wind and low temperature produces a "wind chill."

Look at the wind chill chart that appears on page 48 and you will note that even when the temperature is relatively mild (35 degrees F or 2 degrees C), an accompanying wind blowing at only 20 mph will produce a wind chill that has the same effect on the body as an actual temperature of 12 degrees F (-11 degrees C). If there is a combination of low temperatures and high winds, you must protect yourself and your patient from the dangers of wind chill.


People weakened by old age, exhaustion or hunger are the most susceptible to frostbite. The frostbitten part first becomes numb and then acquires a bright red color. Eventually, the area loses its color and changes to pale white. The frostbitten part must be quickly rewarmed. This can often be easily accomplished by placing the fingers, toes, or ears next to a warm body part. For example, place the frostbitten fingers in the armpits.

Treat the frostbitten patient for shock. DO NOT rub a frostbitten area in an attempt to rewarm it and never rub snow or ice onto a suspected frostbitten area. Doing so will only make the problem worse. A frostbitten patient who has been outside for an extended period of time (for hours) should be transported to a medical facility for rewarming under carefully controlled conditions.

Prevention is the only effective means of combating frostbite. If you are going outside in freezing weather, dress warmly and make sure the vulnerable parts of the body are well covered or protected.

Garry Briese is the executive director of the International Association of Fire Chiefs (IAFC) and, along with David Schottke, co-author of the new edition of First Responder: Your First Response In Emergency Care, available from Jones & Bartlett Publishers. The book is produced by the American Academy of Orthopaedic Surgeons and the National Safety Council.