Heatstroke generally occurs when an individual has been too hot for too long, whether working, exercising, or simply sitting in a hot environment.

Also known as sunstroke, heatstroke is a serious condition and must be considered an emergency.

If left untreated, damage to internal organs can occur. The longer it is left, the more serious heatstroke can become. In some cases, heatstroke can be fatal.

According to the Centers for Disease Control and Prevention (CDC), approximately 1,220 peopleTrusted Source in the United States are killed by extreme heat every year.

In this article, discover the symptoms, causes, and treatments of heatstroke, the possible long-term effects of heatstroke, and how to prevent it from occurring.

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When a person becomes too hot and loses water and salt from the body, leading to tiredness, weakness, and muscle cramps, they experience heat exhaustion.

If the body loses the ability to maintain the correct temperature and becomes dangerously high, it is called heatstroke.

The symptoms of heatstroke can includeTrusted Source:

  • High body temperature: An elevated body temperature (103°F or higher) is the main characteristic of heatstroke.
  • Nausea: This is the feeling of being sick or needing to vomit.
  • Headache: A throbbing headache is common with heatstroke.
  • Heart rate: As the body attempts to cool down, the heart is put under increasing strain, causing the heart rate to rise.
  • Cessation of sweat: A person may stop sweating, and the skin will feel hot, dry, or damp.
  • Color change: The skin may turn red as the body becomes hotter. This can be harder to see in darker skin tones.
  • Mental changes: This can include confusion and loss of consciousness.

The main aim of treating heatstroke is to lower the patient’s temperature and prevent further damage.

There are several potential ways to achieve this, includingTrusted Source:

  • Immersion: Submerge the person in cold water or an ice bath.
  • Evaporation cooling: Mist cold water onto the skin while fanning warm air onto the body. This causes evaporation, which cools the skin.
  • Cooling blankets and ice packs: Wrap cooling blankets around the individual with heatstroke. Place ice packs in regions where large veins come close to the skin’s surface, such as the groin, armpit, neck, and back. This ensures that the temperature of the blood rapidly decreases.

Heatstroke is a serious condition; a person should seek professional medical help immediately.

While waiting for help, the individual should go somewhere less warm and attempt to reduce their temperature with damp sheets, a cold bath, or cooling drinks. A person must avoid alcohol.

Diagnosis

Medical professionals can usually diagnose heatstroke based on a person’s appearance and a discussion about their recent history.

A doctor will sometime order medical tests to rule out other potential causes. Such tests might includeTrusted Source:

  • Blood tests: These measure gas levels and electrolytes, like potassium and sodium, and check for muscle damage, which can occur due to heatstroke.
  • Urine test: This checks for kidney damage. Darker urine is a sign that the patient is dehydrated.
  • Chest X-rays: If there is concern that heatstroke may have caused lung issues, these can help detectTrusted Source any potential damage.

The major causes of heatstroke fall into two categoriesTrusted Source.

Exertional heatstroke

This refers to heatstroke caused by intense activity in a hot environment, whether exercise or work.

Exertional heatstroke is more likely to occur if an individual is not used to high temperatures.

Nonexertional or classic heatstroke

Exposure to a particularly hot environment causes nonexertional heatstroke. Classic heatstroke is most likely to occur if exposed to humid conditions for long periods. Those who are already sick are more susceptible, as are older people.

In both cases, wearing too much clothing, not replacing water lost to sweating, and drinking alcohol, can exacerbate the problem by affecting the body’s temperature regulation.

Although people rarely consider high summer temperatures a health threat, in the U.S., they kill more people than hurricanes, tornadoes, floods, and lightning combined. Therefore, everyone should treat them with caution.

Heatstroke is a potentially life threatening condition, but it is avoidable. Remaining cool and hydrated is essential. Below are some simple waysTrusted Source a person can achieve this:

  • Clothing: Wear loose-fitting, lightweight clothes. These allow the body to cool properly.
  • Fluids: Maintain fluid intake to replace fluids lost through sweating.
  • Parked cars: Never leave someone in a car, as this is a common cause of heatstroke in children. On average, 38 children die in hot cars every year in the USA.
  • Timing: Take extra precautions between 11 am and 3 pm, when temperatures are highest. If it is not possible to cease activity, increase fluid intake and take frequent rests in the shade.
  • Sunburn: Avoid being sunburned, as this affects the way in which the body cools down. Wear a wide-brimmed hat and use sunscreen.
  • Caution: If an individual is at risk of heatstroke, whether due to medications, health status, or age, they should ensure medical services are nearby if they plan to partake in strenuous activity on a hot day.

People often underestimate heatstroke, but they can completely avoid it by following simple recommendations.

Doctors initially believed that recovery from heatstroke, even if prolonged, would normally be complete with no long-term physical deficits. After the 1995 heatwave in Chicago, however, it was discovered that this was not necessarily the case.

During the heatwave, more than 600 people died in just 9 days, and more than 3,000 more were taken to the emergency department. A research teamTrusted Source followed 58 near-death cases of heatstroke to assess any long-term loss of function.

The researchers found that almost half of the participants died within a year, with 21% dying before being discharged from the hospital, and another 28% dying after release.

One-third of those who survived had a “moderate to severe functional impairment” that was not relieved after 12 months.

Similarly, a 2007 studyTrusted Source investigating the long-term outcomes of a heatwave in France discovered that of 83 people with heatstroke, 58% died within 28 days, and 71% died within 2 years.

Anyone can have heatstroke, but some groups are more susceptible than others. Factors that increase the likelihood of heatstroke include the following.

Exertion in high temperatures: Anyone likely to be involved in intense activity in high temperatures is at riskTrusted Source. This commonly includes military personnel and sportspeople.

Age: The CNS monitors and maintains the correct internal temperature. In young children, the CNS is not yet developed, and once a person is over 65 years of age, it slowly deteriorates. Young children and older adults are, therefore, most at riskTrusted Source of heatstroke.

Medications: Some medications can increase the risk of heatstroke by interfering the body’s response to heat or by limiting the ability to stay hydrated.

The following drugs can increase the riskTrusted Source:

Sudden exposure: Heatstroke is more likelyTrusted Source to occur at the beginning of a heat wave or when visiting a much hotter climate.

Sleep deprivation: There is some evidenceTrusted Source that sleep deprivation can increase the chance of heatstroke.

Medical conditions: Some ailments can increaseTrusted Source the risk of heatstroke. These include heart disease, obesity, and poor circulation.

Depending on how long the body temperature is elevated, heatstroke can result inTrusted Source different complications. If a medical professional does not reduce a person’s body temperature quickly, they can experience permanent organ damage.

If they do not receive prompt treatment, heatstroke can be fatal.