Sunstroke and heat stroke

Sunstroke and heat stroke are two acute and dangerous events in which the body’s thermoregulation system does not work.

With sunstroke, the cause is too long a stay in the sun, while heat stroke occurs when the body is exposed to too high a temperature for a long time.

The body is not able to give off heat to return to its normal temperature.
Body temperature rises to such high ranges that important organs can be damaged.

Sunstroke can be preceded by heat exhaustion, which occurs when sweating is associated with too much loss of water and mineral salt, which leads to severe weakness. The heat exhaustion becomes a sunstroke when the body is no longer able to keep the body temperature normal.

Heat exhaustion is a mild disorder accompanied by spasms caused by heat: sudden aching muscle spasms on the arms and legs, and sometimes in the abdominal area.

Heat stroke occurs when a person’s body temperature rises above 40.6°C due to the ambient temperature and the body does not have good thermoregulation (control of temperature).
Heat stroke is not a fever in which the body raises the temperature in response to an infection.


Causes of heat stroke and sunstroke

Heat stroke can be the result of:
– Staying in a hot environment. In a classic heat stroke (not by exertion), the warm environment leads to an increase in body temperature. This type of heat stroke usually occurs after being in a cold and humid climate (tropics), especially if it lasts a long time, for example two or three days. Heat stroke is more common in the elderly and people with chronic diseases.
– Strenuous activities. A stress heat stroke is caused by too intense physical exertion in a hot climate. Anyone who exercises or works in hot climates can suffer a stress heat stroke. The greatest probability is in people who are not used to high temperatures.

Both types of heat stroke can be caused by:
– Wearing too much clothing, which prevents sweat from evaporating easily and cooling the body.
– Drinking alcohol, which affects the body’s ability to regulate temperature.
– It is possible to get a slight sunstroke by irradiation of a UVA lamp. In this case, it is recommended to drink plenty of water and apply a moisturizer.
– Dehydration after heavy water loss due to sweating.

Risk factors

Anyone can suffer sunstroke, however, several factors increase the risk:
age. Infants and children up to 4 years of age or adults over 65 years of age are particularly at risk because they adapt to heat much more slowly than other people.

Performing some sports during the hottest hours of the day, for example, running or cycling (cycling races).
Sudden exposure to the sun, for example, by the sea.
Lack of air conditioning.

Medication. People taking certain medications need to be careful in the warm season, for example in the case of drugs that narrow blood vessels (vasoconstrictors), regulate blood pressure by adrenaline blockade (beta-blockers), flush salt and water out of the body (diuretics) or reduce psychological symptoms (antidepressants or neuroleptics).

Some diseases. There are chronic diseases, such as heart or lung disease, obesity, lack of exercise or previous heat stroke, which can increase the risk of such a disorder.

Symptoms of heat stroke and sunstroke

The symptoms of heat stroke can develop in sensitive people over various days, such as elderly and chronically ill people.
These groups are particularly vulnerable during hot periods.
Symptoms develop faster when caused by physical activity. This type of heat stroke, called exercise heat stroke, usually affects young and active people.

Symptoms of heat stroke include:
– High fever. A body temperature equal to or above 40°C is one of the main signs of heat stroke (although it can be diagnosed even at lower temperatures), but some people can reach these temperatures during physical activity without heat exhaustion or heat stroke.
– Excessive sweating that stops suddenly. When the body can no longer produce sweat, the skin becomes dry, especially the lips and mouth.
– Tachycardia (increased heartbeat) – vasodilation – rapid breathing (hyperventilation) – cramps and muscle pain – swelling (especially leg swelling and facial swelling)

– sun causes excessive lacrimation in the eyes

The extreme heat caused by heat stroke also damages the nervous system and can cause other symptoms such as:
– confusion – lack of coordination
– cramps
– headache (even the following day)
– dizziness or lightheadedness – restlessness or anxiety

– problems understanding or talking to others
– Hallucinations (seeing and hearing things that are not real)
– Loss
of consciousness Rarely, the patient has abdominal pain or diarrhea.

How do I know if my child has heat stroke?
Toddlers or children, in particular, may show signs of heat exhaustion that appear milder than heat stroke. The symptoms are: thirst, fatigueabdominal cramps or leg cramps and cold and damp skin.

If a toddler’s heat exhaustion turns into heat stroke, the child may exhibit the following symptoms:
– fever of 39° and more without sweating
– warm, red and dry skin; if the face was in the sun, the predominantly reddened areas are forehead, nose and cheeks
– tachycardia
– restlessness – confusion – dizziness – headache – vomiting – rapid, superficial excursion
of breath – extreme fatigue (the child could not answer immediately when the mother calls him or tickles him, for example)

– loss of consciousness
It is recommended to pay attention to the signs of dehydration.

Diagnosis of sunstroke and heat stroke

The doctor analyzes the symptoms and measures the blood pressure and fever. Usually, fever is measured in the anus, rather than in the mouth. The doctor may order a blood test and a test of urine.

After how much time do you recognize the disturbance?
The time at which you notice the symptoms depends on the temperature. Since everyone reacts differently, it is difficult to determine the exact time of maximum sun exposure.

What to do? When to call the doctor?

Sunstroke is a medical emergency. The emergency room of a clinic should be visited immediately if someone shows the following symptoms related to heat exposure:
– confusion – extreme fatigue – agitation
– intense muscle pain, fever or nausea

– seizures or loss of consciousness

Treatment and natural remedies for sunstroke and heat stroke

First aid for heat stroke If there is a suspicion that someone has suffered heat stroke

, the emergency number 112 should be notified immediately and the patient taken to a clinic. Late assistance can be fatal.
Before the arrival of the paramedics, first aid must be started. Take the person to a room with air conditioning – or at least a shaded and cool area – and free them from unnecessary clothing.

If possible, measure fever and take initial measures to reduce fever to 38/38.5 degrees (if no thermometer is available, the first emergency measures must be started immediately).

Do not use antipyretic medications, such as aspirin or paracetamol.
Advice for cooling:
– Fanning the wind to the patient while wetting the skin with water or moistening it with a sponge soaked in water.
– Place bags of ice under the armpits, in the groin, on the patient’s neck and back. In these areas there are many superficial blood vessels. If they are cooled, the body temperature can be lowered faster.
– Home remedies include taking a shower or taking a bath in cold water or ice water.
If the emergency service takes longer, direct contact with the rescue coordination center should be maintained in order to receive necessary instructions.

In the hospital

As soon as the patient arrives at the hospital, the treatment is carried out to reduce the body temperature as quickly as possible. Two methods are available: internal and external temperature reduction.

External cold therapy

– ice bath. The patient is placed in a tub filled with water and ice.
– Thermal blanket with ice packs. The patient is wrapped in a thermal blanket and ice packs are placed under the armpits, around the head and neck, as well as in the groins.
– Evaporative cooling. The patient’s body is sprayed with cold water using a nebulizer. A fan provides a lukewarm airflow that accelerates evaporation, thereby dissipating the heat. The speed of cooling that can be measured with this method is about 0.3° C per minute.

The disadvantages of the ice bath or the thermal blanket with ice packs are peripheral vasoconstriction and chills.
With these two methods, treating a patient with cardiac arrest or bradycardia (very slow heartbeat) is particularly difficult.

Internal cold therapy

The methods of internal cooling can reduce the patient’s temperature the fastest. For example:
– gastric lavage, rinsing of the bladder and enema with cold water, which are performed minimally invasively.
– In extremely severe cases, peritoneal irrigation and chest drainage can be performed.
– Cardiopulmonary bypass is a very rare but very effective method.

What are the consequences of sunstroke?

Heat exhaustion is not dangerous if treated properly. Sunstroke, however, can be fatal if not treated appropriately. If the cooling mechanism does not work, the body temperature rises very rapidly and death can occur in less than 30 minutes.

Some people also die many weeks after such an initially acute episode due to complications of renal failure or heart failure. More than 10% of affected people die from sunstroke. Sunstroke can cause permanent damage to other organs, such as the liver.


Infants and young children are more susceptible to extreme heat and therefore rely on the prudence of others to be sufficiently cool and hydrated.
– Never leave newborns or children in a parked car (even if the windows are open). Also, pets (dogs or cats) should never be left in parked cars (they can get sick due to the heat).
– Dress infants and toddlers with loose, casual and light-colored clothing.
– Do not drink sweet or alcoholic beverages to quench your thirst. These drinks interfere with the body’s ability to regulate body temperature. In addition, too cold drinks can trigger stomach cramps.

How long does it take? Prognosis

The duration of symptoms depends on the severity of sunstroke.
Normally, the time of regeneration is 24-48 hours, but in severe cases this can take much longer, such as in the case of 2nd degree burns.
If a patient stays in too high an ambient temperature for a few hours, this can have consequences. For example, the brain may be damaged or rhabdomyelosis (decay of muscle fibers) may occur.

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