Why deaths occur due to heat stroke

Sub : Sci

Sec: Health

Context:

The recent airshow in Chennai, resulting in five fatalities and numerous cases of heat-related illnesses highlighted the dangers of prolonged heat exposure.

What is a heat stroke:

Heat stroke, also known as sun-stroke is a condition caused by excess heat in the body.
This usually happens because of exposure to high temperatures or physical activity in high temperatures for too long.
Heat stroke occurs when your body gets overheated (body temperature of 40°C or above) and cannot cool itself down.
Symptoms: severe headache, dizziness, nausea and confusion. In some cases, it can cause seizures, or coma and can be fatal.

Factors influencing heat retention:

According to the World Health Organisation, the amount of heat stored in the body is determined by a combination of two factors:
1. an inability to eliminate internally generated heat from metabolic processes due to environmental health stress (such as high temperature, high humidity)
2. clothing creating a barrier to heat loss and external heat gain from the environment.
When the body can’t control its temperature and get rid of extra heat, it raises the chances of heat stroke.

How does heat impact health:

Normal metabolic activity occurs at 38 to 39 degrees Celsius, and overheating can trigger dizziness and excessive sweating.
Excessive sweating can lead to dehydration, thickening the blood and complicating circulation.
This may result in decreased blood pressure and oxygen saturation levels, heightening the risk of serious health issues.

Effects of dehydration:

Dehydration can increase sodium concentration, leading to hypernatremia, which may cause brain haemorrhages.
Potential impacts on metabolism, affecting sodium, potassium, and fluid balance, leading to encephalopathy.

Vulnerable Population:

Elderly people are particularly susceptible to heat stroke due to thinner skin and a higher likelihood of dehydration.
Pre-existing health conditions can exacerbate the effects of heat exposure.