What is Hypothermia? Symptoms, Causes, and Treatment

Hypothermia

Hypothermia is the drop of body temperature to values lower than they should be. A body temperature of 35 °C or below indicates that hypothermia is occurring. It can be caused by internal and external factors such as cold regions, cool seasons, as well as medications, burns, skin diseases, and certain health problems. Hypothermia affects all body tissues, and symptoms depend on the severity of heat loss. During prolonged cold exposure, the body begins to consume more heat and energy than it produces. The consumption of stored energy causes the body temperature to drop.

Hypothermia can intensify depending on how many degrees the temperature drops. A very low body temperature can negatively affect brain functions and lead to dangerous consequences because the person may not realize they have hypothermia and may not be able to seek medical intervention. Although it is more common in low-temperature environments, it can also occur in normal-temperature environments. It frequently affects adults in the 30-49 age group, but it can occur at any age. Hypothermia, which affects men more than women, can cause life-threatening situations in severe cases. Therefore, it is a medical emergency and requires intervention. Untreated hypothermia can result in kidney failure, liver damage, cardiac arrest, coma, and death.

What is Hypothermia?

Hypothermia is a condition where the body temperature is 35 °C or below. Body temperature is formed by a specific balance between the heat produced by the body and the heat released into the environment. In a healthy person, the average body temperature is 36.5-37.5 °C. The body loses heat through various mechanisms to maintain the balance of body temperature. Heat loss can occur through conduction, evaporation, respiration, convection, and radiation. Evaporation and respiration involve the loss of water droplets along with heat. Evaporation is the conversion of liquid to gas through heat. These mechanisms can trigger hypothermia in dry, windy, and cool environments. Convective heat loss is the cooling that occurs when air molecules pass by an object with a certain temperature. In windy environments, the layer of air in direct contact with the skin carries heat away from the body, and therefore, heat changes such as the cooling effect on the body are observed in windy conditions. Heat radiation, which is the fastest form of heat loss, is related to the body emitting electromagnetic energy into the environment. Heat loss through conduction involves the heat exchange that occurs between objects in contact. The stages of a drop in body temperature, i.e., hypothermia, are classified as mild, moderate, and severe:

Mild hypothermia: A drop in body temperature to 32 to 35 °C.

Moderate hypothermia: A drop in body temperature to 28 to 32 °C.

Severe hypothermia: Also known as deep hypothermia. It is when the body temperature is below 28 °C.

Staging methods are used to bring body temperature under control and for hypothermia treatment.

What Are the Symptoms of Hypothermia?

Symptoms of hypothermia may vary depending on the stage of heat loss. Symptoms of mild hypothermia, where body temperature drops to 32-35 °C, are non-specific and mild in severity. Symptoms of mild hypothermia may include:

Shivering,

Nausea,

Hunger,

Fatigue,

Dry and pale skin,

Slow movements and reactions,

Rapid heartbeat and weak pulse,

Rapid breathing,

Drowsiness,

Excessive urination,

Difficulty speaking,

Confusion.

Moderate hypothermia is a medical condition that occurs when the body temperature drops to 28-32 °C. It includes advanced cognitive function and skin symptoms. These symptoms may include:

Dilated pupils,

Abnormal heart rhythm and low blood pressure,

Weakness in reflexes,

Slowed heart rate and breathing,

Retardation in mental functions,

Hallucinations,

Decreased shivering,

Bluish skin color,

Increased muscle stiffness.

A body temperature dropping below 28 °C indicates severe hypothermia. It can be a life-threatening condition and requires emergency medical intervention. Symptoms of severe hypothermia are:

Low blood pressure,

Loss of reflexes,

Low heart rate and arrhythmia,

Decreased urine,

Fluid in the lungs,

Complete muscle stiffness,

Cardiac arrest,

Coma and death.

Symptoms of hypothermia in infants may include cold and bright red skin, inactivity, and loss of energy.

What Causes Hypothermia?

Body temperature is controlled by the hypothalamus center in the brain. It ensures body temperature homeostasis by evaluating signals from the central and peripheral nervous systems. The hypothalamus tries to cope with hypothermia by conserving and producing heat. Heat conservation is achieved through behavioral responses such as increasing insulation (wearing thick clothes), lighting a fire, and exercising. Heat production is influenced by physiological activities such as thyroxine, catecholamines like adrenaline, adrenal hormones, basal metabolic rate, and shivering. In response to cold, basal metabolism, muscle tone, and adrenaline and thyroxine hormone levels are increased. Thanks to these responses, heat production in the body increases approximately twofold. In addition to the increase in basal metabolic rate and muscle tone, heat production is increased approximately two to five times as a result of shivering. In addition to cold exposure, common causes of hypothermia include:

Aging,

Malnutrition,

Hypoglycemia (low blood sugar),

Burns,

Cold and rainy outdoor activities,

Alcohol use,

Drug use,

Skin diseases such as psoriasis and dermatitis,

Hypothyroidism,

Hypoadrenalism,

Hypopituitarism,

Anorexia nervosa,

Diseases such as Parkinson's disease and dementia,

Head and spinal cord injuries,

Tumors,

Wernicke's disease,

Stroke,

Infants and young children lose heat more easily than adults. Furthermore, they do not have sufficient energy stores to increase body temperature. Hypothermia in infants and children may go unnoticed due to excessive energy consumption during movement. Additionally, medications such as anesthetics, sedative hypnotics, beta-blockers, and neuroleptics can also be among the causes of hypothermia.

How is Hypothermia Diagnosed?

During the diagnosis of hypothermia, medical history, the presence of injury and trauma, environmental exposures, and symptoms are examined. Patients with hypothermia often have a history of cold exposure. Therefore, emergency examination is provided against the risk of respiratory and cardiac arrest. Detecting symptoms effectively is an important step during diagnosis. Airway and breathing, circulation, consciousness, and disability are evaluated quickly during the primary examination. Vital signs such as loss of consciousness, cessation of breathing, and absence of pulse are checked in the person. Staging techniques are used clinically during the diagnosis phase of hypothermia. Mild hypothermia can be more difficult to detect in the elderly.

Standard clinical thermometers may not be sufficient for a definitive diagnosis. In particular, most thermometers used for oral measurement may not read temperatures below 35 °C. Rectal and bladder temperatures can be measured while patients with mild and moderate hypothermia are conscious. Special low-reading rectal thermometers, rectal thermistor probes, tympanic thermometers, and bladder probes are devices that can be used during the diagnosis phase. In some cases, more than one method can be used simultaneously. In addition, temperature can be measured with an esophageal probe for definitive results in patients with an open airway.

How is Hypothermia Treated?

Hypothermia treatment includes first aid applications and medical treatment. During first aid, it is important to move the person only as much as necessary. Massage, rubbing, and severe or jarring movements should be avoided. The patient should be moved to a dry and warm environment as much as possible and protected from cold and wind. If the patient, who is kept in a flat position, is wearing wet and cold clothes, they should be removed or the clothes should be cut. For heating purposes, the person should be covered with thick fabrics such as dry blankets or coats. The patient may appear unconscious even without signs of pulse and breathing. Basic life support should be provided by trained individuals to a patient whose breathing has stopped or who has shallow breathing. If the person is conscious and can swallow, warm/hot caffeine-free and non-alcoholic liquids can be given. In addition, the body can be warmed by applying compresses made with warm or slightly hot water without applying them directly to the skin. When medical intervention teams arrive, emergency care applications are performed to raise the body temperature. Medical assistance includes:

In case of mild hypothermia, a heated blanket and warm fluid support are provided.

Intravenous solutions may be given to help warm the blood.

The patient's blood is drawn, warmed using a hemodialysis machine, and returned to the body.

Airways can be warmed and body temperature can be raised by using humidified oxygen with the help of a mask or tube.

Additional methods can be used for the treatment of hypothermia in infants. Hypothermia can be applied as a treatment in the management of some health problems and can be indicated as hypothermia indications.

Frequently Asked Questions

People in cold environments, infants and young children, the elderly, those engaged in outdoor activities in windy, snowy, cold, and rainy weather, homeless people, those who use alcohol and drugs, those with hormonal disorders, those who have suffered injuries and trauma, and those with stroke, anorexia nervosa, Parkinson's, dementia, sepsis, and skin diseases may be at risk for hypothermia. In addition, drug groups such as sedatives, anesthetics, opioids, and antipsychotics can alter or impair the body's response to cold. Hypothermia can manifest itself by affecting many organs and systems in the body. It can be divided into mild, moderate, and severe symptoms. In general, it can have effects such as paleness in the skin, feeling of cold, dryness, shivering, drowsiness, confusion and difficulty speaking, weakness in reflexes, decrease in heart rate and blood pressure, palpitations and arrhythmia, rapid and shallow breathing, exhaustion, nausea, hallucinations and mental function retardation, stiffness in muscles, cardiac arrest, coma, and death. People suspected of having hypothermia or showing symptoms must receive emergency medical intervention. Therefore, the person should not be made to wait, first aid should be provided, and the emergency assistance center should be called. In the presence of any or several of the symptoms of hypothermia, first aid should be obtained from trained individuals. First aid for hypothermia begins with gently moving the patient to a warm, hot, and dry environment and not moving them too much. The emergency response teams should be reached and a detailed patient history should be provided. The person's breathing and pulse should be checked, and airway patency should be ensured. The person should be protected from harsh weather conditions as much as possible and kept in a flat position. Wet, tight, and cold clothes should be removed gently, and the person should be covered with several layers of dry blankets or jackets. Basic life support should be provided to a patient who is not conscious and whose breathing and pulse have stopped. Hypothermia can be fatal if timely and appropriate treatment is not provided. Patients with mild hypothermia can recover completely without the risk of long-term complications if they receive emergency medical assistance. In people with moderate and severe hypothermia, life risk can be reduced with timely and correct treatment. Dressing in layers in cold, snowy, windy, and rainy conditions, having warm clothes available, keeping the home environment above 20 °C, ensuring the body moves, consuming hot food and drinks, taking regular warming breaks, and avoiding alcohol and certain medications are the right approaches to preventing hypothermia. Hypothermia does not resolve on its own and can continue until heating is provided. Therefore, the duration of hypothermia cannot be determined. Emergency intervention must be provided to prevent complications and overcome life-threatening risks. Recurrence of hypothermia is related to the correction of the underlying condition. Body temperature can be returned to normal by removing the sources leading to hypothermia and with appropriate treatment, but recurrent hypothermia attacks may be seen due to congenital or acquired disorders. These attacks can give symptoms such as slowed movements, confusion, sweating, and slowing of the heartbeat. For hypothermia, specialist doctors in the department of endocrinology and metabolism diseases can be consulted. Help can be obtained from specialists in different departments for the affected body regions in providing diagnosis and treatment.

Hypothermia Can Carry a Life-Threatening Risk. Do Not Be Late!

Hypothermia is an emergency condition that can lead to serious and life-threatening consequences if not intervened in time. If there are symptoms such as shivering, confusion, difficulty speaking, or extreme weakness that develop after exposure to cold, medical support should be sought without wasting time.