Sunstroke, Heat Exhaustion and Heat Stroke

Symptoms and causes

1. sunstroke results from excessive sun exposure to the head, causing heat buildup and irritation of the meninges (aseptic meningitis):

  • Headache
  • Neck stiffness
  • Nausea, vomiting
  • Feeling of heat in the head
  • Dizziness, restlessness

2. In heat exhaustion, there is an overheating of the body with a body temperature between 37 to 40°C. Underlying, in addition to the increased heat, is dehydration. Symptoms include:

  • Feeling of warmth (“fever”)
  • Headache
  • Nausea and vomiting, feeling sick.
  • Loss of appetite
  • Chills
  • Muscle weakness, general weakness and fatigue.
  • Rapid pulse rate (tachycardia)
  • Low blood pressure, possibly unconsciousness
  • Thirst
  • Visual disturbances
  • Sweating
  • Dizziness, but no severe central nervous disturbances as in heat stroke.

3. Heat stroke is defined as a body temperature above 40°C with central nervous disturbances such as delirium, clouding of consciousness, hallucinations, agitation, convulsions, and coma. Other symptoms and complications include:

  • Rapid pulse rate (tachycardia), low blood pressure (hypotension).
  • Hot and dry skin
  • Dehydration
  • Respiratory problems
  • Brain swelling
  • Dissolution of the musculature (rhabdomyolysis)
  • Organ failure, renal and liver failure.
  • Death

Other clinical pictures: Heat collapse (heat fainting): collapse or fainting during prolonged exposure to the sun, often while standing. Caused by vasodilatation and decrease in cerebral blood flow. Risk factors include dehydration and low blood pressure. Heat cramps are painful spasms of skeletal muscles in the arms, legs, and abdomen caused by heat, sodium deficiency, and fluid loss. An important risk factor is the use of diuretics. They also often occur after physical exertion. Comorbidities: Conjunctivitis (snow blindness), sunburn.

Risk factors

Exogenous factors:

Endogenous factors:

  • Physical exertion
  • Excess weight
  • Diseases, including fever, heart disease, hyperthyroidism, disorders of sweating.
  • Dehydration is a risk factor and leads to exacerbation
  • Individual factors

Age:

  • Young people who play sports (e.g. sports day).
  • Elderly people during a hot spell
  • Children

Prevention

  • Avoid risk factors
  • Keep the home and the body cool
  • Take enough fluids and electrolytes to themselves
  • Wear appropriate, light clothing and headgear
  • Acclimatization: when exercising repeatedly or staying in the heat, the organism adapts with physiological changes (increased salt retention, increased sweating).
  • Avoid physical exertion

Treatment

Sunstroke and heat exhaustion: the patient should go to a cool place, cool down (for example, with a shower) and rest. The most important measure is to drink enough fluids and electrolytes. Depending on the severity and if there is no improvement, medical treatment is necessary. If significant central nervous disturbances occur, heat stroke should be considered. Heat stroke: Heat stroke is a medical emergency and requires immediate medical treatment (tel. 144)! The patient must be cooled as soon as possible. In first aid, the patient should be assessed according to the ABC scheme and, if possible, cooled in a cool environment.Heat cramps: In this case, the administration of sodium (saline solutions, electrolyte replacement solutions) is the primary additional measure. Heat exhaustion: As an additional measure, elevate legs. Provide adequate fluids Nonsteroidal anti-inflammatory drugs and acetaminophen are used but are controversial in the scientific literature because they may increase organ toxicity.