HEATWAVE: the rising public health dangers of extreme heat

admin Pormoll

A heatwave is declared when the maximum temperature is at least 40oC in plains, 37oC in coastal areas, and 30oC in mountains.

What does extreme heat do to our bodies?

Our bodies strive to keep a core temperature of about 37 oC whether we’re in a snowstorm or a heat wave. It is the temperature our bodies have evolved to work at. As the body gets hotter, blood vessels open up. This leads to lower blood pressure and makes the heart work harder to push the blood around the body. This can cause mild symptoms such as an itchy heat rash or swollen feet as blood vessels become leaky. At the same time, sweating leads to the loss of fluids and salt and, crucially, the balance between them in the body changes. This, combined with the lowered blood pressure, can lead to heat exhaustion. Symptoms include:

  • Dizziness and confusion
  • Nausea, loss of appetite and feeling sick
  • fainting
  • muscle cramps
  • headaches
  • excessive sweating
  • tiredness
  • fast breathing or pulse
  • a temperature of 38 oC or above
  • being very thirsty

Young children, who might not be able to tell you about how they are feeling, may become floppy and sleepy.

Heat exhaustion can turn into heatstroke, which is an emergency. It means your body can no longer manage the heat and your core temperature is rising too high. Get urgent medical help. The signs to watch for and quickly act on:

  • feeling unwell after 30 minutes of resting in a cool place and drinking plenty of water
  • not sweating even while feeling too hot
  • a temperature of 40 oC or above
  • fast breathing or shortness of breath
  • feeling confused
  • a fit (seizure)
  • loss of consciousness
  • not responsive

What to do

If someone has heat exhaustion:

  • get them to rest in a cool place – such as a room with air conditioning or somewhere in the shade
  • remove any unnecessary clothing, to expose as much of their skin as possible
  • cool their skin – use whatever is available, a cool, wet sponge or flannel, spray water, cold packs around the neck and armpits, or wrap them in a cool, wet sheet
  • fan their skin while it is moist – this will help the water to evaporate, which will help their skin cool down
  • get them to drink water
  • get medical help

Tips for Surviving a Heat Wave While It’s Happening

  • Stay hydrated with plenty of water—even if you’re not thirsty. Hot weather causes you to sweat, and it’s vital to replenish the lost fluids or you’ll overheat.
  • Never leave children or pets alone in hot vehicles—even for a second. Keep your pets indoors and make sure they have access to a cool space and plenty of water.
  • Stay inside during the hottest part of the day (10 A.M to 4 P.M.) and limit time outside in the sun. Avoid strenuous activity and postpone outdoor games and events.
  • When you’re in the outdoors, make sure you stay out of direct sunlight as much as possible. Wear a hat or even carry an umbrella. Wear sunscreen.
  • Don’t drink alcohol, sugary soda, coffee, energy drinks, or other caffeinated beverages, as they dehydrate you.
  • Eat small meals and eat more often. Eat food with nutrients and also food with higher water content (fruits and vegetables).
  • Wear light, loose-fitting, airy, light-coloured clothing and a hat made of breathable material. Tight clothing traps heat.

Dr. Divya Vaz