Body temperature is controlled in the part of the brain called the hypothalamus, which is responsible for recognizing alterations in the body temperature and responding appropriately. The body produces heat through the metabolic processes in cells that support vital body functions. Most heat is lost at the skin surface by convection, conduction, radiation, and evaporation. If the environment gets colder, the body may need to generate more heat by shivering (increasing muscle activity that promotes heat formation). But if heat loss is greater than the body's ability to make more, then the body's core temperature will fall.
As the temperature falls, the body shunts blood away from the skin and exposure to the elements. Blood flow is increased to the vital organs of the body including the heart, lungs, kidney, and brain. The heart and brain are most sensitive to cold, and the electrical activity in these organs slows in response to cold. If the body temperature continues to decrease, organs begin to fail, and eventually death will occur
During good weather conditions, you tend to ignore the weather. If it’s sunny, you’ll probably feel warm and neglect to carry proper clothing necessary in the event of inclement weather. You may even lack food and rudimentary shelter and equipment necessary for survival in an emergency. If the weather changes suddenly, or you or a member of your party is injured, you may find yourself unprepared to face such adverse conditions.
Hypothermia symptoms usually begin slowly. As you develop hypothermia, your ability to think and move often becomes clouded. In fact, you may even be unaware that you need help. As your thought process is impaired, you fail to realize that you are becoming colder. Once you get cold, it can be very difficult to get warm again.
Someone with hypothermia is likely to have frostbite as well.
- You don’t need to be experiencing sub-zero temperatures to encounter hypothermia.
- Your judgment will be impaired making you much more likely to experience an accident.
- Uncontrollable shivering (although, at extremely low body temperatures, shivering may stop followed by rigidity of muscle)
- Weakness and loss of coordination
- Confusion, Irrationality, poor judgment
Pale and cold skin
- Cyanosis (Blueness of Skin)
Exhaustion or drowsiness- especially in more severe stages
- Slowed breathing or heart rate
- Thickness of Speech-Poor articulation of words
- Loss of perceptual contact with environment
- Dilation of pupils
- Decreased heart and respiration
- Slowness of pulse, irregular or weak pulse
- Drop in body temperature below 95 F
- Loss of consciousness
- Numb hands or feet
- In infants, symptoms include: Bright red, cold skin, Very low energy level
Get the person indoors Remove wet clothing and dry the person off, if needed Restore Warmth Slowly Warm the person's trunk first, not hands and feet. Warming extremities first can cause shock. Warm the person by wrapping him or her in blankets or putting dry clothing on the person. Do not immerse the person in warm water. Rapid warming can cause heart arrhythmia. If using hot water bottles or chemical hot packs, wrap them in cloth; don't apply them directly to the skin. If the person is not breathing normally: Begin CPR, if Necessary, While Warming Person Continue CPR until the person begins breathing or emergency help arrives. Give Warm Fluids. Give the person a warm drink, if conscious. but avoid caffeine or alcohol. Keep Body Temperature Up, Once the body temperature begins to rise, keep the person dry and wrapped in a warm blanket. Wrap the person's head and neck as well.