What are the stages of hypothermia? What temperatures cause hypothermia? Who is at risk for hypothermia? Get answers to these questions and more in this comprehensive article.

Stages of Hypothermia: Understanding the Progression

Hypothermia is a serious medical condition that occurs when the body’s core temperature drops below the normal range. As the body loses heat faster than it can produce it, the stages of hypothermia become increasingly severe. Let’s explore the five stages of hypothermia in detail:

Stage 1: Mild Hypothermia (95-89.6°F)

In the initial stage of mild hypothermia, the individual may experience normal or near-normal consciousness and shivering as the body attempts to generate heat. This stage is characterized by a core body temperature between 95 and 89.6 degrees Fahrenheit.

Stage 2: Moderate Hypothermia (89.6-82.4°F)

As hypothermia progresses, the individual’s shivering may stop, and their consciousness becomes impaired. The core body temperature at this stage ranges from 89.6 to 82.4 degrees Fahrenheit.

Stage 3: Severe Hypothermia (82.4-75.2°F)

In severe hypothermia, the individual becomes unconscious, and it may become difficult to detect vital signs. The core body temperature at this stage is between 82.4 and 75.2 degrees Fahrenheit.

Stage 4: Apparent Death (75.2-59°F)

At this stage, the individual appears to be dead, with a core body temperature between 75.2 and 59 degrees Fahrenheit.

Stage 5: Irreversible Hypothermia (Below 59°F)

In the final stage of hypothermia, the individual has reached a core body temperature below 59 degrees Fahrenheit, which is considered irreversible and ultimately leads to death.

Temperatures that Cause Hypothermia

Contrary to popular belief, hypothermia can occur at a wide range of temperatures, not just in extremely cold environments. Any conditions where the body loses heat faster than it can generate it can lead to hypothermia. Rapid drops in temperature, even if the air temperature is not extremely low, can cause hypothermia. In some cases, particularly for older adults living in hotter regions, entering a building with the air conditioning set too low can also lead to accidental hypothermia. Prolonged exposure to extremely cold water, even in hot locations, can also cause hypothermia.

Who is at Risk for Hypothermia?

Certain individuals are more susceptible to hypothermia than others. Young children and older adults are at an increased risk for accidental hypothermia, even at temperatures that may not be dangerous to others. Other risk factors include:

• Taking certain medications
• Having diabetes
• Thyroid conditions
• Mental illness
• Somatosensory disorders or nerve damage
• Medical conditions that impair the body’s ability to maintain a normal temperature, such as arthritis, hypothyroidism, dehydration, and Parkinson’s disease
• Malnutrition

Complications of Hypothermia

As hypothermia progresses, the body experiences a cascade of complications. The individual may initially shiver in an attempt to generate heat, but this shivering will eventually subside. In severe cases, the individual may feel warm as their body dilates blood vessels in a last-ditch effort to warm their freezing limbs. Other complications include:

• Shallow or slow breathing
• Slurred speech
• Fumbling hands, loss of coordination, and stumbling steps
• Slow, weak pulse
• Drowsiness or exhaustion
• Confusion and memory loss
• Loss of consciousness
• Lack of a strong pulse or respiration

Recognizing and Responding to Hypothermia

If you or someone you know is suspected of having hypothermia, it is crucial to call 911 immediately. Hypothermia can worsen quickly, and getting the individual to a location where they can receive medical treatment as soon as possible could be the difference between life and death. While waiting for emergency services, you may be directed to provide first aid, but this should only happen after you have called 911 if possible.

Conclusion

Hypothermia is a serious medical condition that requires immediate attention. Understanding the stages of hypothermia, the temperatures that can cause it, and the risk factors can help you recognize the signs and respond effectively. Remember, if you suspect someone is suffering from hypothermia, the first and most important step is to call 911 for emergency medical assistance.

TrustCare | Hypothermia Explained

Many people have had the experience of being so cold they lose feeling in their fingers and toes. This is a good indication you have been in a cold environment for too long, and need to get warm soon. Having your fingers and toes stay cold for too long can put you at risk of frostbite, but if your whole body stays cold for too long, you could be at risk of the far more dangerous condition of hypothermia.

Hypothermia is a medical emergency, and needs to be treated as such. If you or someone you know is suspected of having hypothermia, call 911 immediately. The effects of hypothermia can worsen quickly, and getting someone to a location where they could receive medical treatment as soon as possible could be the difference between life and death. You may be directed by emergency services to provide first aid while health care professionals are on the way, but this should only happen after you have called 911 if possible.

What are the Symptoms of Hypothermia?

The signs of hypothermia are generally easy to recognize, though some change as the condition progresses. Shivering, for example, that is apparent in mild hypothermia will often subside as your condition worsens. In fact, in extreme cases of hypothermia you may feel very warm as your body dilates blood vessels in a last ditch attempt to warm freezing tissue in your limbs. Common symptoms of hypothermia include:

• shivering (Though this may stop as symptoms increase in severity.)
• shallow or slow breathing
• slurred speech
• fumbling hands, loss of coordination, stumbling steps
• a slow, weak pulse
• drowsiness or exhaustion
• confusion and memory loss
• loss of consciousness
• lack of a strong pulse or respiration

What are the Five Stages of Hypothermia?

Hypothermia results from a drop in your core body temperature that you cannot correct with your own body heat. As you progress from mild hypothermia to a more extreme state of heat loss, you will experience some very identifiable symptoms. What is most dangerous is that confusion and slowed mental activity often compounds people’s ability to help correct their low body temperature.

Agencies such as the Centers for Disease Control and Prevention (CDC) offer differing standards in emergency medicine for evaluating hypothermia. One scale breaks cases into three categories of mild, moderate, and severe hypothermia, with core body temperature readings and symptoms being the differentiators between the three categories. There is also a five stage scale that is used, particularly in Canada, to further classify the progression of heat loss in a hypothermic individual.

HT I: Mild Hypothermia, 95-89.6 degrees
Normal or nearly normal consciousness, shivering

HT II: Moderate Hypothermia, 89.6-82.4 degrees
Shivering stops, consciousness becomes impaired

HT III: Severe Hypothermia, 82. 4-75.2 degrees
Unconscious, may be difficult to detect vital signs

HT IV: Apparent Death, 75.2-59 degrees

HT V: Death from irreversible hypothermia

Who is at Risk for Hypothermia?

Anyone who spends time outside in extremely cold weather may be at risk for hypothermia. Young children and older adults are also at increased risk for accidental hypothermia even at temperatures that may not be dangerous to others.

Other risk factors that can make you more susceptible to hypothermia include taking certain medications, having diabetes, and possibly even some thyroid conditions. Mental illness and some kinds of somatosensory disorders or nerve damage are often cited as risk factors as well, since people with these conditions may not be aware of the sensations from their bodies, or may not take appropriate action if they do.

Medical conditions can impair your body’s ability to maintain a normal body temperature or to sense cold include:

• arthritis
• hypothyroidism
• dehydration
• diabetes
• Parkinson’s disease
• a stroke
• spinal cord injuries
• burns
• malnutrition

Medications such as some antidepressants can also make you more susceptible to suffering from hypothermia.

What Temperatures Cause Hypothermia?

Some people believe incorrectly that hypothermia can only happen from exposure to cold water or in cold temperatures at snowy locations in the winter. In reality, hypothermia can strike at a wide range of temperatures. Any conditions where your body temperature drops faster than your body can maintain heat can put you at risk of hypothermia.

Rapid drops in temperature can cause hypothermia, even if the air temperature is not very low. As surprising as it may seem, in some cases, particularly for older adults living in hotter regions, it is possible that entering a building where the air conditioning is set too low could cause accidental hypothermia. Prolonged exposure to extremely cold water, even in hot locations, can sometimes also cause hypothermia.

Complications of Hypothermia

On the road to hypothermia, your body will often go through extremely cold temperatures. This can cause damage to tissues throughout the body. A few of the most common complications associated with hypothermia include:

• frostbite, or tissue destruction caused by tissues freezing
• chilblains, or nerve and blood vessel damage
• gangrene, or tissue death
• trench foot, a nerve and vascular condition from continuous water immersion
• death

How Do You Warm Someone With Hypothermia?

Providing first aid to someone who is hypothermic could save their life, but it must be done correctly. In cases of severe hypothermia, there is a chance that providing the wrong assistance could increase a person’s risk of suffering from cardiac arrest. The first thing to do is always to call 911.

If you are attempting to provide first aid to someone suffering from hypothermia, rewarming them should be the goal, but must be done carefully. Any wet clothes should be removed immediately, and they should be wrapped in warm blankets. Heat should be applied to help the person get back closer to normal body temperature by putting hot water bottles or heating pads around the individual’s chest, armpits, and groin. If hot water or heating pads are not available, using your own body heat may help in rewarming someone suffering from hypothermia. If the person suffering from hypothermia is still conscious, giving them warm liquids like tea, coffee, or soup can also help to raise body temperature.

If you are suffering from hypothermia and are taken to a medical facility, there are more options available to help warm you up. In addition to applying warm compresses to the torso, armpits, and groin, warm saline solution can be given intravenously. Warming the stomach cavity is also possible by pumping warm water into the stomach. In extreme cases, it may also be possible to remove and warm your blood before pumping it back into your body.

No matter the cause, it is essential that medical professionals are contacted immediately if hypothermia is suspected. Damage to organs and tissues can occur the longer symptoms persist, so getting help as quickly as possible from emergency medical personnel trained and equipped to handle hypothermia is crucial to keeping someone alive and safe if they are suffering from a sudden, irreversible drop in body temperature.

Hypothermia First Aid – Recognizing the Stages of Hypothermia

By: Rebel Coombes

Treatment for Hypothermia

I began writing this blog about hypothermia first aid, and then had the unfortunate experience of becoming hypothermic myself. Hypothermia is a condition that is caused by cold. The body can begin having signs and symptoms of hypothermia when immersed in water as warm as 86F/30C degrees. There is a lot of water in the United States that is at or below 86F/30C degrees! Global freshwater temperatures typically average between 65F/18C to 75F/24C in the summer and 35F/2C to 45F/7C in the winter. Global surface temperatures of oceans are around 61F/16C. I will share a little about my experience and then talk about how to recognize, prevent, and treat hypothermia.

My Experience with First Aid for Hypothermia

Scuba divers in particular need to know how to administer first aid for hypothermia. I work on a dive rescue recovery team. We were on a night recovery mission in spring, with water surface temperatures at 74F/23C. I was stationed on the surface as a 90%’er in a dry suit with minimal thermal protection. For the recreational/sport diver, this means 90% ready to go underwater and affect a rescue or other task that may become necessary. I was a little chilled but figured the feeling would disappear as soon as I began working. I was called upon to begin a search, and felt great underwater. I warmed up tremendously and was quite comfortable. The pattern was a little rough due to a few issues with my dive computer compass and orientation. I was diving in near zero visibility with unfamiliar terrain at night, but remained calm in executing my task. It was then determined by command to surface. As I slowly ascended, I began feeling extremely cold within about three meters of the surface. Once on the surface I had a brief conversation with another diver, and then began to shiver uncontrollably. It was observed that I was blue and was subsequently rushed to shore for assessment by paramedics and crew. It took a little while to recover to normal temperature, but I recovered without any other complications.

Recognizing the Stages of Hypothermia

Being able to identify early stages of hypothermia is critical. Normal body temperature is 98.6F/37C. According to the Cleveland Clinic, hypothermia begins when the body temperature drops below 95F/35C. The Cleveland Clinic states that hypothermia can occur in temperatures above 104F/40C in conditions in which a body gives off more heat than it generates, such as a wet and windy environment, or when combined with other medical conditions such as diabetes. Never discount hypothermia just because it is hot outside.

Stages of Hypothermia

There are three stages of hypothermia. Most will only see one or two stages, but hypothermia can very easily result in death if left untreated.

The signs of mild hypothermia consist of:

• Shivering
• Chattering teeth
• Exhaustion
• Clumsiness
• Slow reaction time
• Being prone to falling
• Weak pulse
• Tachycardia (rapid pulse)
• Tachypnea (rapid breathing)
• Pale skin
• Confusion or loss of awareness
• Excessive urination

The second stage of hypothermia is a little more frightening and unfortunately the stage I progressed to. Core body temperature ranges between 89.6F to 82.4F.

• The heart and breathing begin to slow
• Slurred speech or difficulty speaking
• Decline in mental function
• Loss of shivering
• Bluish in color
• Muscle stiffness
• Dilated pupils
• Arrythmias (heart abnormalities)
• Hypotension (decreased blood pressure)
• Muscle weakness
• Loss of consciousness

The final stage of hypothermia is a core temperature below 82. 4F/28C.

• Hypotension
• Pneumonia (fluid in the lungs)
• Absence of reflexes
• Low urine output

These are the hallmark symptoms, followed by a coma mimicking death, and finally, death. This is why knowing how to give first aid for hypothermia is so important. 

We all love to dive. Most of us want to maximize our time underwater and hate to call a dive. But remember, there is no room for ego! If you begin feeling cold you should end the dive or activity you are participating in. One of the first signs of feeling cold is goosebumps. The medical term for this is excitement of the erector pili muscles. Many of us wear at least a wetsuit so you may not see goosebumps, but shivering is an easily recognizable sign. If your dive buddy is shivering, there is a problem. Make sure they know you are okay with calling the dive. There are other days to dive and you do not want to end up a statistic on dives gone bad.

How to Spot the Early Stages of Hypothermia

If their lips and nail beds are pure white, it means the body has already started shifting the blood to the core, protecting the organs. Medical professionals call this compensated shock. Delayed capillary refill is when blood does not return to the nailbed quickly. The test for this is as simple as pushing on their fingernail. If it does not go from pink to white and back to pink after two seconds, you need to end the dive and start first aid.

Check the pulse in their wrist by applying pressure where the wrist and thumb meet. If you can’t find it, feel their neck on either side or have them find their own pulse. Some dive computers can also track heart rate. Normal heart rate is between 60 and 100 beats per minute. There are many extremely athletic folks among us who have such good heart health that a rate of 40 beats per minute might be their normal. If you ask your buddy, they will probably know if they usually have a slow heart rate. In the first stages of hypothermia, the heart rate will be elevated between 100 and 150 beats per minute. Respirations are tracked by watching the chest or abdomen rise and fall. Remember, this can be overridden by our brain so try to count when they are not focused on their breathing. Between 10 and 20 respirations per minute is the “Normal Range”. And finally, if they are running to the bushes, head, or Porta John after the dive, ask how they are feeling and if they are diabetic.

More severe hypothermia is much easier to notice. The victim may seem like they are drunk. Slurred speech, staggering, and inability to walk indicate this second stage of hypothermia.. Pulse will have slowed again to below 60 beats per minute and they may be only breathing 8 times per minute or less. The final stage is clear, and in the environment that we work or play in, the second stage is usually bad enough for the victim to be complaining about!

Now that we know what to look for, how do we treat hypothermia?

1. Warm them gently and carefully. DO NOT RUB THEM. This can cause tissue damage and result in further injury.
2. Take off all wet clothing! Remember that you lose heat 25 times faster in water than you do in a dry environment. Adding wind to wet only makes things worse. Undress the victim and give them warm, dry blankets. If the individual is alert and able to swallow, provide a warm, nonalcoholic, non-caffeinated beverage, this may also help warm them up and make them feel better.
3. Get them out of the wind and into a dry, warm environment. On a dive boat, head to the head or galley. At a quarry, go to your vehicle with the heat on. At the beach, find a changing house or guard station.
4. If you have hot packs or warmed vessels, put them on the sides of the neck, under the Axilla(armpits,) and in the groin. Be careful to not let them burn the skin. The goal is to warm the areas enough to heat the deep vasculature of the groin, armpits, and neck. Do not apply heat to the arms or legs since that will force cold blood back to the heart, lungs, and brain causing the core body temperature to drop.
5. Call 911 as early as possible. Even if they stand there and look at you like you are silly. Your treatment and calling emergency medical services early may be the difference between life as normal and no longer being able to dive/live.

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Hypothermia: causes, symptoms, diagnosis and treatment

03/01/2021

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Hypothermia is a decrease in the internal temperature of the body to 35 ° C and below as a result of the predominance of heat transfer over heat production. A warm-blooded organism is characterized by a relatively constant temperature. During the day, it changes only by + 0.5 degrees. S.

Hypothermia, breaking this constancy, causes a complex of pathophysiological disturbances in vital organs and systems. These violations are due to protective and adaptive reactions of the body aimed at restoring normal temperature. The primary reaction of the body to the action of cold is a spasm of peripheral vessels in order to reduce heat transfer.

As the temperature cools and a temperature gradient develops between various organs and tissues, shivering occurs, which prevents a further drop in the temperature of internal organs and contributes to an increase in the temperature of superficial tissues. This is accompanied by an increase in oxygen consumption and an increased breakdown of glycogen in the muscles. Initial hyperglycemia is replaced by hypoglycemia and severe dysfunction of vital organs. A state arises when the protective reactions of the body cross the line of expediency and become pathological.

GENERAL

Hypothermia (hypothermia) is a pathological condition that can be life-threatening for the patient. According to statistics, about 700 people die each year due to hypothermia in the US, 300 in the UK, and 100 in Canada. Experts believe that the real number of deaths from hypothermia is higher, since this condition is not always diagnosed. Pathology is ubiquitous, more common in northern and temperate latitudes, the number of cases increases in the cold season. The risk of developing hypothermia is increased in the extreme age groups – infants and young children, the elderly and the elderly. In sparsely populated areas, hypothermia usually occurs due to insufficient preparation for staying in existing weather conditions. In cities, the homeless and those who are intoxicated after drinking alcohol are more likely to become victims of hypothermia.

CAUSES OF COOLING

Hypothermia develops as a result of increased heat loss, which cannot be compensated for by increased heat production by the body. Heat loss occurs as a result of conduction, convection and evaporation. Conduction is the direct transfer of heat from the body to the environment, convection is the loss of heat during the movement of water or air in the immediate vicinity of the surface of the body, evaporation is the release of heat with water during sweating, breathing. There are four main causes of hypothermia:

• Lack of heat production. It is observed in premature babies, senile people, patients with alimentary dystrophy, exhaustion against the background of severe injuries, acute and chronic diseases. It is found in some hormonal disorders – hypocorticism, hypopituitarism and hypothyroidism.
• Increased heat loss. It is noted with vasodilation due to intoxication (most often alcohol), medication. It develops with prolonged exposure to dry cold, immersion in cold or cool water. It is determined in some skin pathologies, for example, ichthyosis, psoriasis and exfoliative dermatitis. Sometimes it becomes the result of medical actions (during long-term surgical interventions, massive transfusion of cold solutions).
• Disorders of thermoregulation. Detected in certain diseases and traumatic injuries of the central and peripheral nervous system, accompanied by sensory disorders (for example, damage to large nerve trunks, paralysis due to stroke, craniocerebral or spinal cord injury, especially high, multiple sclerosis, tumors of the central nervous system, Parkinson’s disease ). May occur under the influence of certain toxins and medications.
• Within critical conditions. Can be determined in polytrauma, massive blood loss of various origins, acute pancreatitis, septic conditions, extensive burns, uremia, diabetic ketoacidosis. It is provoked by violations of thermoregulation, increased percutaneous water loss, behavioral disorders and other reasons.

Often, pathology has a polyetiological origin. For example, in the elderly and bedridden patients with insufficient care, age-related or due to impaired thermoregulation lack of heat production, low room temperature, and chronic diseases matter. The most significant external factors are ambient temperature, humidity and wind strength. When exposed to air without movement at zero temperature, death occurs within 10-12 hours, under similar conditions in water – after half an hour.

The influence of the wind is calculated on the basis of the wind-chill index, there are special tables compiled taking into account this indicator, reflecting the risk of hypothermia or frostbite under certain weather conditions. Despite the increase in the risk of developing hypothermia as the temperature drops, the largest number of cases of the disease in healthy people, according to the observations of traumatologists, is associated with being outdoors in conditions of low positive rather than negative temperatures, which can be explained by insufficient alertness, unpreparedness for external conditions. environment.

PATHOGENESIS

Hypothermia is a two-stage process, including the stage of compensation, which occurs when the body tries to correct the violation of the thermal balance, and the stage of decompensation, which develops when the mechanisms of temperature regulation are disrupted. In the compensation stage, the body’s reactions are activated, aimed at reducing heat loss and increasing heat production. The patient changes behavior (finds shelter, puts on warm clothes, turns on the heater, uses blankets, etc.). By constricting peripheral vessels and reducing sweating, heat loss through the skin is reduced. The blood flow in the internal organs increases, involuntary muscle contractions (muscle tremors) occur, providing an increase in heat production. Increased diuresis. There is a release of hormones that are involved in stress reactions that increase the body’s defenses in extreme circumstances.

With the inefficiency of adaptive mechanisms and a further decrease in body temperature, the central mechanisms of thermoregulation are violated, heat production becomes uncoordinated and inefficient. The central temperature drops below 35°C, poikilothermic reactions occur, vicious circles form, aggravating the patient’s condition. Due to a decrease in temperature, the intensity of tissue metabolism decreases, which leads to a further decrease in temperature and a decrease in metabolism. The narrowing of the peripheral vessels is replaced by their expansion, which entails an increase in heat loss, which provokes further dilatation of the vessels.

Due to the disturbance of the activity of nerve centers, muscle trembling stops, which potentiates a drop in body temperature and further inhibition of the central mechanisms of regulation of muscle activity. Hypothermia of the central nervous system is the cause of a decrease in brain activity, resulting in impaired consciousness, drowsiness, and apathy. Active actions become impossible, the patient freezes, which reduces the chances of salvation. There comes a state of apparent peace, pseudo-comfort, which subsequently turns into a coma and ends with the death of the patient.

CLASSIFICATION

There are several classifications of hypothermia. Since the severity of manifestations does not always coincide with the severity of hypothermia, to assess the reversibility of the process, hypothermia is sometimes systematized taking into account the central body temperature. According to this division, there are four stages of pathology: three reversible (mild – 32-33°C, moderate – 28-32°C, severe – 24-28°C) and one irreversible (extremely severe – less than 24°C). However, in clinical practice, a classification is more often used, compiled on the basis of the prevailing compensatory reactions and including three degrees of hypothermia:

• Light or adynamic (32-34°C) . Accompanied by activation of the mechanisms of heat generation, narrowing of peripheral vessels, stress stimulation of the sympathetic nervous system.
• Medium or soporous (29-32°C) . It is manifested by the depletion of compensatory mechanisms, slowing down of metabolism in the central nervous system, discoordination of the work of cortical and subcortical nerve centers, depression of the respiratory and cardiac centers in the medulla oblongata, significant deterioration or cessation of blood flow in peripheral vessels, possibly frostbite.
• Severe or comatose (below 31°C) . It is characterized by disruption of compensation mechanisms, severe metabolic disorders and serious disorders of the brain structures, disruption of the conduction system of the heart, damage to peripheral tissues up to icing.

SYMPTOMS OF HYPOCOOLING

With a mild degree of , chills, muscle tremors occur, the skin becomes pale, acquires a bluish tint. “Goosebumps” and typical speech disorders are revealed. Mild bradycardia is noted. Blood pressure is usually unchanged or slightly increased, breathing is rapid. Initially, the patient is actively moving, taking measures to save. With continued exposure to cold, the patient becomes lethargic and lethargic. Speech, thought processes and reactions to external influences slow down. Some patients have superficial frostbite.

With an average degree of , further aggravation of bradycardia, a slight decrease in blood pressure and a decrease in breathing to 8-12 6 respiratory movements per minute are determined. The cyanosis of the skin intensifies, it becomes especially pronounced in the area of ​​the nose, ears, distal extremities, the likelihood of frostbite increases. The amount of urine excreted decreases due to a decrease in renal blood flow. Muscle trembling stops, the muscles stiffen, the patient takes a forced posture – rounds the back, bends the arms and legs, brings them to the body. Severe drowsiness turns into hypothermic sleep and then into a coma, the reaction to external stimuli is significantly weakened, often detected only with painful effects. The pupils are dilated and reactive to light.

In severe , there is a pronounced cyanosis of the skin, intense muscle stiffness. The pulse rate drops to 20-30 beats. per minute, arrhythmias are determined, fibrillation is possible. Rare shallow breathing is replaced by periodic (Biot or Cheyne-Stokes). The separation of urine stops due to the development of acute renal failure. The patient is in a state of deep coma, there are no reactions to all types of stimuli, a weak reaction of the pupils to light is possible. There are recurring generalized convulsions with an interval of up to half an hour. Deep widespread frostbites are revealed, icing of peripheral parts of the body (fingers, hands, feet, parts of the face) is possible, spreading in the proximal direction. When the central temperature drops below 20°C, respiratory arrest and cardiac arrest are determined.

COMPLICATIONS

In the early period, fibrillation, cerebral edema, and pulmonary edema may occur. Acute renal failure is often diagnosed. The likelihood of infectious complications, including pneumonia, surgical wound infection, increases. Sometimes errors in warming become the cause of negative consequences, overheating may occur due to the breakdown of thermoregulation mechanisms, a drop in blood pressure and cardiac arrest due to reflex vasodilation when the temperature rises too quickly. With deep frostbite, amputation of the limb may be required. In a number of patients, neurological disorders are detected in the long-term period.

DIAGNOSIS

The diagnosis is established on the basis of an external examination, anamnesis data (in case of severe hypothermia, the data are established from the words of eyewitnesses who found the victim, or ambulance staff) and the results of measuring body temperature. The armpit measurement reflects surface temperature and is not a reliable indicator of the presence or absence of hypothermia. The measurement is carried out rectally, using an esophageal probe or in the nasopharyngeal region, given that the rectal temperature may differ slightly from the baseline, and readings taken in the esophagus may be unreliable due to previous warm air therapy. In modern clinical practice, special electronic thermometers are used, equipped with a probe, calibrated in the range of low temperatures. It is possible to measure the temperature of a fresh portion of urine. The best option is to take several measurements in different places. It should be borne in mind that the fall in the base temperature below critical values, the absence of heartbeat and respiration cannot be considered as evidence of the death of the patient (a case of survival at a temperature of 9°C, as well as recovery after the cessation of cardiac activity for 3 hours) due to the action of hypothermia, which slows down the development of irreversible 8 processes in tissues. Death is declared only in the absence of signs of life after warming. To confirm the diagnosis, along with the measurement of temperature, an ECG is prescribed, on which the Osborne wave is detected. The list of other laboratory and instrumental studies in case of suspicion of this pathology includes KLA, OAM, determination of urea, creatinine, glucose, electrolytes, acid-base state and blood pH, coagulogram, measurement of blood pressure and hourly diuresis, pulse oximetry, chest x-ray. In case of injuries of the musculoskeletal system, X-rays of the corresponding segment are performed, with possible damage to internal organs, ultrasound, CT or MRI are prescribed, according to indications, laparoscopy and other studies are performed.

HYPOCOOLING TREATMENT

Treatment is carried out by specialists in the field of practical traumatology and resuscitation. Therapeutic tactics is determined by the degree of hypothermia, the nature and severity of violations of the body’s vital functions. In all cases, it is urgent to stop exposure to cold, to take measures for passive warming. Patients with a mild degree are prescribed a warm drink (sweet tea), a warm bath, heating pads, avoiding the use of excessively heated liquids. In case of superficial frostbite, warming bandages are applied to the limbs. In moderate and severe cases, intensive complex therapy is necessary, including etiotropic, pathogenetic and symptomatic measures. Etiotropic treatment involves passive (blankets, warm dry clothes) and active (warm bath, applying heaters to the passage of large vessels) warming. Active warming is carried out using a liquid whose temperature exceeds the temperature of the victim by no more than 10 ° C. After the rectal temperature rises to 33-34°C, the procedure is stopped in order to avoid possible overheating against the background of the thermoregulation system that has not yet recovered. Along with the above methods, it is effective to warm the lungs by supplying moist air or an oxygen mixture heated to 42-44 ° C, intravenous infusions of warm solutions. In case of resistance to the above methods, mediastinal lavage, extracorporeal warming of the blood (hemodialysis, cardiopulmonary, veno-venous and arteriovenous shunting), washing of the stomach, bladder, rectum, pleural cavity with warm solutions are performed. ramie, however, these techniques are associated with the risk of complications, therefore, they are not used as part of standard therapy. At the heart of pathogenetic treatment are measures to restore the activity of the respiratory and cardiovascular systems, correct metabolic disorders. Carry out the release of the respiratory tract, conduct mechanical ventilation. If necessary, defibrillate. Perform infusion infusions of dextran, saline solutions, glucose solution with vitamins and insulin, according to indications – transfusions of plasma and plasma substitutes. As part of symptomatic therapy, drugs are prescribed to normalize urination, increase blood pressure, eliminate pain, prevent pulmonary and cerebral edema, and correct existing somatic pathology. When determining the plan for drug correction of the patient’s condition, it is taken into account that drugs in conditions of severe hypothermia may be ineffective or have an unpredictable effect and should be used after sufficient warming. Frostbite is treated.

FORECAST AND PREVENTION

The prognosis usually (with the exception of particularly severe cases) depends more on comorbidity than on the severity of hypothermia. Mortality among healthy people is low. In the presence of severe injuries and somatic diseases, mortality rates increase dramatically. A characteristic feature of this condition is the possibility of recovery after a long cessation of the activity of vital organs, due to the protective effect of cooling. Preventive measures include choosing clothes and planning activities outside warm shelters, taking into account weather conditions, correcting pathological conditions that are risk factors, ensuring optimal temperature conditions in rooms, especially when people living in them have a predisposition to developing hypothermia.

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There are 3 stages of hypothermia – Studopedia

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Stage 1 – compensation.

Body temperature remains at a normal level, although the ambient temperature is low, which is achieved by limiting heat transfer, activation of the sympathetic-adrenal system, causing spasm of skin microvessels, thereby limiting heat transfer. At the same time, there is an increase in heat production due to an increase in motor activity, contraction of the smooth muscles of the skin (“goosebumps”), and an increase in oxidative processes in tissues.

Stage 2 – relative compensation .

Develops at very low ambient temperature or violation of the thermoregulation system. At this stage of development of hypothermia, there is a combination of thermoregulation disorders and protective-adaptive reactions (intensification of oxidative processes in tissues). Heat transfer prevails over heat production, which causes a decrease in body temperature.

Stage 3 – decompensation.

Hypoxia develops due to weakening of external respiration, depression of cardiac activity, microcirculation disorders, and a decrease in oxidative processes in tissues. The patient becomes indifferent to the environment, immobilized, there is a strong physical weakness, bradycardia and a drop in blood pressure, rare shallow breathing. A person has a deep sleep. If he is not helped, he will die. With hypothermia, the body’s need for oxygen decreases, resistance to pathogenic influences increases, which are used in severe surgical operations (general and local hypothermia or “artificial hibernation”).

Fever.

Fever – a general reaction of the body to damage, the most important sign of which is an increase in temperature. This is a typical pathological process that occurs under the action of a pyrogenic agent, which is based on an active restructuring of the functions of the thermoregulation center. Fever is one of the frequent manifestations of diseases, sometimes it can be the first and only symptom of the disease for a long time.

Etiology of fever:

The fever is polyetiologic. According to the etiology, fever is divided into non-infectious and infectious.