Coping with hot weather

26th July 2019

This discussion on coping with warm weather was recently posted by our specialist helpline nurse Jayne Partridge on our closed Facebook group.


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Anyone can find the hot weather difficult to cope with, however if you have a heart condition you might find the heat can affect you more.

This is because when the weather is hot your heart has to work harder to pump blood to the surface of your skin to assist with sweating to cool your body. This can sometimes increase the work of your heart. When you sweat to cool down you lose more fluid than usual from your body. This can lower you blood pressure and make you heart beat faster. Always check with your GP or cardiologist for advice if you are on a fluid restriction and are concerned about your fluid intake during a period of hot weather. Otherwise try to take frequent sips of fluid such as water and try to reduce caffeine based drinks which can make you more dehydrated.

You might find that you need to rest more in the hot weather because your heart is working harder to keep you cool. Try to find a cool room and wear light comfortable clothing.

Sometimes medications prescribed to people who have been diagnosed with a heart condition, such as cardiomyopathy or myocarditis can sometimes reduce a person’s ability to cool off in the heat, therefore try and reduce the time you are outside in the sun and try to keep indoors and as cool as possible. You may need to speak to your GP or heart nurse if you are taking diuretics and are concerned about safe levels of fluid intake during a period of hot weather.

How to cope in hot weather

The main risks during a heatwave (daytime temperature of 30 degrees) and hot weather are:

  • Dehydration - not having enough water
  • Overheating - which can make symptoms worse for people who have heart or breathing problems.
  • Heat exhaustion and heat stroke.

Tips for coping in hot weather:

  • Avoid the heat if you can - try and stay out of the sun and don't go out between 11am and 3pm if you are vulnerable to the effects of heat.
  • Shut windows and pull down the shades when it is hot outside, open the windows for ventilation when it is cooler.
  • Keep rooms cool by drawing curtains.
  • Have cool baths or showers and splash yourself with cool water.
  • Drink cold drinks regularly, such as water or diluted fruit juice. Avoid excessive alcohol, caffeine (tea, coffee and cola) or drinks high in sugar.
  • Listen to alerts on the TV, radio and social media about keeping cool.
  • Plan ahead to make sure you have enough supplies of water food and any medications you need.
  • Identify the coolest room in the house so you can go there to keep cool.
  • Wear loose, cool clothing and a hat and sunglasses if you go outdoors. Sit outside during the cooler hours and sit in the shade in the shade or under an umbrella.
  • Eliminate or limit physical activity during the hottest parts of the day and do light exercise during the cooler hours.
  • Take light meals; avoid hot heavy meals and reduce use of your oven to keep cool.
  • Some medications can increase your risk for heat stress, ask your pharmacist if any of your medications could increase your risk.

Signs of heat related problems are:

  • Headache, nausea and fatigue are signs of heat stress.
  • Heat fatigue - signs are cool moist skin, a weakened pulse and feeling faint.
  • Heat cramps - signs are muscle spasms in the abdomen, arms or legs after exercise.
  • Heat exhaustion - this is a warning that the body is getting too hot. Watch for thirst, giddiness, dizziness, weakness, lack of co-ordination, nausea and profuse sweating. Cold or clammy skin. Body temperature may be normal. Pulse is normal or raised slightly. Passing urine may decrease and vomiting may occur.
  • Heat stroke - this is a very serious immediate medical attention is required. Body temperature rises, the person becomes confused, behaves bizarrely, feels faint, and staggers. Pulse is rapid, skin is dry and flushed and may feel hot. Lack of sweating. Breathing may be fast and shallow.

To alleviate symptoms whilst waiting for medical help:

  • Have the person lie down in a cool place.
  • Elevate the feet.
  • Cool them with a hand held fan
  • Apply cool wet cloths or water to the skin
  • Give them small sips of cool water.

The person may feel tired and weak for a few days after suffering with heat stress.

Seek help from a GP or contact NHS 111 if someone is feeling unwell (or 999) and shows symptoms of:

  • Breathlessness
  • Chest pain
  • Confusion
  • Intense thirst
  • Weakness
  • Dizziness
  • Cramps which get worse or don't go away

Enjoy the warmer weather but remember to stay safe and help to keep others safe especially children.

Cardiomyopathy Nurse Jayne