Hypothermia, also known as low body temperature, describes the condition when the core temperature of the human body falls below 35.0°C.
Generally, hypothermia occurs when the body loses more heat than it can generate, leading to a decrease in core body temperature and a range of symptoms, including shivering, confusion, and even heart and lung failure, potentially resulting in death.
There are two main causes of hypothermia. The most common is exposure to extremely low temperatures. The other cause involves situations that inhibit the body’s heat-producing mechanisms or increase the rate of heat loss.
Conditions Predisposing to Hypothermia: Prolonged exposure to cold environments results in the depletion of the body’s energy reserves, leading to hypothermia. When the heat loss surpasses heat gain, it results in abnormally low body temperature.
Low body temperature affects cognitive function, hindering the ability to take timely protective measures. Individuals may not be aware that hypothermia is occurring, and the lack of prompt protective measures makes hypothermia more dangerous.
While hypothermia typically occurs in extremely cold weather, it can also happen in 4-5°C weather if exposed to rain or soaked in cold water in a damp environment.
Vulnerable Populations for Hypothermia: People vulnerable to hypothermia include:
- Elderly individuals lacking sufficient food, clothing, or heating devices.
- Infants sleeping in cold indoor environments.
- Individuals spending extended periods outdoors.
- Homeless individuals, hikers, and others engaging in outdoor activities.
- Individuals under the influence of alcohol.
Symptoms of Hypothermia: Hypothermia is categorized into three stages: mild, moderate, and severe.
Stage 1 (Mild Hypothermia): Body temperature drops to 32°C–35°C. Symptoms include shivering, numbness in the extremities, difficulty performing complex movements, rapid and shallow breathing, “goosebumps” on the skin, fatigue, abdominal pain, and abnormal increased urination.
Sometimes, individuals with mild hypothermia may feel warmth, which is a signal that it is progressing to stage 2. A test for the progression to stage 2 is the ability to touch the thumb and little finger, representing the first stage of muscle failure.
Stage 2 (Moderate Hypothermia): Body temperature drops to 28°C–32°C. Symptoms intensify with more pronounced muscle incoordination, slowed and difficult movements, unsteady gait, and confusion. Skin color may turn pale, with lips, ears, fingers, and toes turning blue. There may be an unusual tendency to remove clothing due to vasodilation, providing a transient illusion of warmth.
Stage 3 (Severe Hypothermia): Body temperature drops to approximately 28°C or below. Muscle tremors usually cease. Individuals may experience difficulty speaking, mental sluggishness, skin discoloration, almost complete loss of muscle coordination, inability to walk, and even unconsciousness. Pulse and respiration significantly slow, potentially leading to rapid heart rate or atrial fibrillation and, ultimately, heart and lung failure.
First Aid for Hypothermia: If an adult exhibits signs such as shivering, collapse, fumbling hands, memory loss, slurred speech, or drowsiness, or if an infant has bright red, cold skin, it is crucial to measure the body temperature. If it falls below 35°C, seek medical attention immediately.
In the absence of immediate medical help, raise the body temperature by:
- Moving the person to a warm room or shelter.
- Promptly removing wet clothing.
- Taking measures to warm the core areas of the body—chest, neck, head, and groin.
- Providing warm beverages to help raise the body temperature (avoiding alcoholic beverages), but do not administer to an unconscious person.
- Seeking medical attention as soon as the situation stabilizes.
Preventing Hypothermia:
- Familiarize yourself with local weather conditions and dress accordingly.
- Use windproof and protective clothing during cold weather outings. Essential items include a warm hat, gloves, a scarf, windproof jacket, thick socks, windproof face mask, and even protective eyewear.
- Keep the body dry during outdoor activities, and change into dry clothing if exposed to rain or water.
- Choose moisture-wicking undergarments instead of cotton to prevent heat loss.
- Regulate clothing layers to avoid overheating, excessive sweating, and fatigue.
- Carry high-calorie food for energy, and stay hydrated to prevent dehydration.
- Be aware of your physical limits, avoid overexertion, and replenish energy through food and hot drinks as needed.
- In the event of hypothermia, seek emergency treatment promptly at an emergency or burn unit.