Heatstroke is the most serious form of heat-related illness and is a medical emergency. If you suspect that someone has heatstroke – which some people refer to as sunstroke – you should call 999 immediately and render first aid until paramedics arrive.
Heatstroke can kill or cause damage to the brain and other internal organs. Although heatstroke is most common in babies, the elderly and those with long-term medical conditions, it also takes a toll on healthy young physically active people such as athletes.Heatstroke often occurs as a progression from milder heat-related illnesses such as heat cramps, heat syncope ( fainting) and heat exhaustion. However, it can strike even if you have no previous signs of heat injury.
Heatstroke results from prolonged exposure to high temperatures – usually in combination with dehydration – which leads to failure of the body’s temperature control system. The medical definition of heatstroke is a core body temperaturegreater than 41°C, with complications involving the central nervous system that occur after exposure to high temperatures. Other common symptoms includenausea, rapid heartbeat, muscle cramps, seizures, confusion, disorientation, cessation of heavy sweating and sometimes loss of consciousness or coma.
Risk factors for heatstroke
Heatstroke is most likely to affect older people who live in flats or homes lacking good airflow and with inadequately shaded south-facing windows. Other high-risk groups include babies and young children, and people of any age who don’t drink enough water, have chronic diseases, have mental disabilities or who drink excessive amounts of alcohol. People who spend a lot of time being physically active in hot weather are also at greater risk.The risk of heat-related illness dramatically increases when the heat index climbs to 26°C or more. So it’s important – especially during heatwaves – to pay attention to the maximum temperature reported in your local weather forecasts and to remember that it will be hotter in the sun than in the shade.
If you live in an urban area, you may be especially prone to develop heatstroke during a prolonged heatwave, particularly if there are stagnant atmospheric conditions and poor air quality. In what is known as the “heat island effect,” asphalt and concrete store heat during the day and only gradually release it at night, resulting in higher night-time temperatures.
Prevention of heatstroke:
Monitoring the colour of your urine. Darker urine is a sign of dehydration. Make sure you drink enough fluids to maintain very light-coloured urine.Measuring your weight before and after physical activity. Monitoring lost water weight can help you determine how much fluid you need to drink.
Avoid fluids containing caffeine or alcohol. Both substances can make you lose fluids and worsen heat-related illness. Also, do not take salt tablets unless your doctor has told you to do so. The easiest and safest way to replace salt and other electrolytes during heat waves is to drink sports drinks or fruit juice.
Check with your doctor before increasing liquid intake if you have epilepsy or heart,kidney or liver disease, are on fluid-restricted diets, or have a problem with fluid retention.
If you live in a flat or house without fans, try to spend at least two hours each day – preferably during the hottest part of the day – in an air-conditioned environment. Avoid rooms with south-facing windows, which get the most sunlight. At home, draw your curtains or blinds during the hottest part of the day. If you can, open windows at night on two sides of your building to create cross-ventilation.