Hypothermia: Causes, Symptoms, and Treatment

What is Hypothermia?

Hypothermia is a medical emergency that occurs when your body loses heat faster than it can produce heat, causing a dangerously low body temperature. Normal body temperature is around 98.6°F (37°C). Hypothermia occurs when your body temperature drops below 95°F (35°C).

When your body temperature drops, your heart, nervous system, and other organs cannot work normally. Left untreated, hypothermia can lead to complete failure of your heart and respiratory system and eventually to death.

Hypothermia is most often caused by exposure to cold weather or immersion in cold water. However, prolonged exposure to any environment colder than your body can lead to hypothermia if you aren't dressed appropriately or can't control the conditions.

Certain medical conditions, medications, and other factors can make you more susceptible to hypothermia.

Common Causes

Hypothermia occurs when your body loses more heat than it generates. Common causes include:

• Cold weather exposure: Being outside in cold weather without adequate protective clothing is a major cause, especially in windy or wet conditions.
• Cold water immersion: Falling into cold water, such as a lake or river, can rapidly lower body temperature. Water conducts heat away from the body much faster than air.
• Inadequate clothing: Wearing clothes that don't insulate well or aren't appropriate for weather conditions can lead to heat loss.
• Alcohol or drug use: Alcohol and certain drugs can impair judgment and cause blood vessels to expand, increasing heat loss.
• Medical conditions: Conditions like diabetes, hypothyroidism, stroke, severe arthritis, Parkinson's disease, trauma, spinal cord injuries, and malnutrition can affect the body's ability to regulate temperature.
• Medications: Some medications, such as sedatives, antidepressants, antipsychotics, and narcotic pain medications, can interfere with the body's temperature regulation.
• Older age: Older adults are more vulnerable due to slower metabolism, reduced ability to sense cold, and other age-related factors.
• Very young age: Infants and young children lose heat faster than adults and may not be able to communicate discomfort or move to a warmer location.
• Homelessness or poverty: Lack of access to warm shelter, adequate clothing, or heating can increase the risk.
• Prolonged immobility: Being unable to move, such as after a fall or during an illness, can lead to hypothermia as the body generates less heat.

According to the Mayo Clinic, even indoor environments can lead to hypothermia if they are too cold, especially for vulnerable individuals.

Associated Symptoms

Hypothermia symptoms depend on how low your body temperature has dropped. Early signs and symptoms include:

• Shivering, which is your body's attempt to generate heat
• Cold, pale, or blue-gray skin
• Lack of coordination, such as stumbling or fumbling hands
• Slurred speech or mumbling
• Slow, shallow breathing
• Weak pulse
• Fatigue or exhaustion
• Confusion or memory loss
• Loss of consciousness
• Bright red, cold skin (in infants)
• Very low energy (in infants)

As hypothermia progresses, shivering may stop, and symptoms can worsen to include:

• Drowsiness or very low energy
• Weak pulse
• Slow, shallow breathing
• Progressive loss of consciousness
• Eventually, the person may appear dead

If you notice someone exhibiting these symptoms, especially after exposure to cold, seek emergency medical help immediately. According to the Centers for Disease Control and Prevention (CDC), recognizing these symptoms early can be life-saving.

When to See a Doctor

Call 911 or your local emergency number if you suspect someone has hypothermia. While waiting for emergency help to arrive, follow the first-aid advice below.

Seek immediate medical attention if you or someone else has:

• Confusion, memory loss, or difficulty speaking
• Slurred speech or mumbling
• Uncontrollable shivering or sudden lack of shivering
• Drowsiness or very low energy
• Loss of coordination, such as stumbling or fumbling hands
• Slow, shallow breathing
• Weak pulse
• Loss of consciousness

If you're not sure whether someone has hypothermia, err on the side of caution and seek medical help. It's better to be safe than sorry. The National Institutes of Health (NIH) emphasizes that hypothermia is a medical emergency and requires prompt treatment.

Diagnosis

A diagnosis of hypothermia is usually apparent based on a person's physical signs and the conditions in which the person became ill or was found. However, doctors will typically follow these steps to confirm and assess the severity:

• Medical history: Doctors will ask about the events leading up to the symptoms, including exposure to cold, duration of exposure, and any underlying medical conditions or medications.
• Physical examination: This includes checking vital signs such as pulse, breathing rate, and blood pressure. Doctors will also look for signs of cold exposure, such as cold skin, shivering, and mental confusion.
• Temperature reading: A special low-temperature thermometer is used to get an accurate core body temperature reading. Regular thermometers may not read low enough to diagnose hypothermia.
• Blood tests: These can help assess the severity of hypothermia and check for complications, such as abnormal blood pH (acidosis), low blood sugar, or abnormal electrolyte levels.
• Electrocardiogram (ECG or EKG): This test measures the electrical activity of the heart. Hypothermia can cause abnormal heart rhythms, which an ECG can detect.
• Other tests: Depending on the severity and associated symptoms, doctors may order additional tests, such as a chest X-ray or urine tests, to check for infections or other complications.

The Johns Hopkins Medicine notes that quick and accurate diagnosis is crucial for effective treatment and recovery.

Treatment Options

Treatment for hypothermia depends on the severity of the condition. The goal is to raise the body temperature to a normal range while supporting vital organ functions. Here are the common treatment approaches:

First Aid and Initial Treatment

If you suspect someone has hypothermia, take the following steps while waiting for emergency help:

• Move the person out of the cold: If possible, move the person to a warm, dry location. If you can't move the person, shield them from the cold and wind.
• Remove wet clothing: Carefully cut away wet clothing if necessary. Replace with warm, dry coats or blankets.
• Cover the person's head: Use a hat or scarf to cover the head, leaving only the face exposed.
• Insulate the person's body: Use blankets, towels, or even your own body heat to warm the person. Focus on the chest, neck, groin, and armpits.
• Monitor breathing: If the person is unconscious or not breathing, begin CPR if you are trained to do so.
• Avoid direct heat: Do not use hot water, a heating pad, or a heating lamp to warm the person. Direct heat can cause burns or damage the skin.
• Do not rub the person's limbs: Vigorous rubbing can cause cardiac arrest in someone with severe hypothermia.
• Offer warm beverages: If the person is conscious and able to swallow, offer warm, non-alcoholic, non-caffeinated beverages to help warm the body.

Medical Treatment

In a hospital setting, doctors may use several techniques to rewarm the body and treat complications:

• Passive rewarming: For mild hypothermia, using blankets and a warm room may be sufficient.
• Active external rewarming: This involves applying warm packs or blankets to the body, often focusing on the torso.
• Active internal rewarming: For severe hypothermia, warm fluids may be given intravenously, or warm, humidified oxygen may be administered. In some cases, doctors may use a technique called extracorporeal rewarming, where blood is removed, warmed, and circulated back into the body.
• Medications: Doctors may administer medications to treat complications such as abnormal heart rhythms or infections.
• Oxygen therapy: Supplemental oxygen may be provided to support breathing and oxygen levels in the blood.
• Intravenous fluids: Warm intravenous fluids can help raise body temperature and support circulation.

The Cleveland Clinic highlights that treatment must be tailored to the individual's condition and that medical supervision is crucial for severe cases.

Prevention Tips

Preventing hypothermia involves planning ahead, dressing appropriately, and being aware of the risks. Here are some practical tips:

• Dress in layers: Wear multiple layers of loose-fitting, lightweight clothing. The outer layer should be windproof and waterproof. Wool, silk, or polypropylene inner layers hold body heat better than cotton.
• Cover your head, hands, and feet: A significant amount of body heat is lost through the head and extremities. Wear a hat, mittens (rather than gloves), and warm, waterproof boots.
• Stay dry: Wet clothing chills the body rapidly. Remove wet clothing as soon as possible. Avoid sweating, as damp clothing can accelerate heat loss.
• Stay hydrated and nourished: Drink plenty of fluids and eat regular meals to maintain energy. Avoid alcohol and caffeine, as they can increase heat loss.
• Be aware of weather conditions: Check the forecast before heading outdoors. Pay attention to wind chill, which can make the temperature feel much colder.
• Take breaks indoors: If you're outside in cold weather, take regular breaks in warm, dry locations.
• Use the buddy system: When engaging in outdoor activities, go with a friend or group. This way, you can monitor each other for signs of hypothermia.
• Prepare your home and car: Ensure your home is well-insulated and heated. Keep emergency supplies in your car, such as blankets, warm clothing, and a thermos with a warm beverage.
• Check on vulnerable individuals: Regularly check on older adults, young children, and those with medical conditions during cold weather.
• Be cautious with outdoor activities: Avoid prolonged exposure to cold, especially in water. If you fall into cold water, get out as quickly as possible.

The World Health Organization (WHO) emphasizes the importance of community awareness and preparedness in preventing cold-related illnesses.