St John Ambulance provides first aid advice for noticing and treating symptoms of common conditions including heat exhaustion, sunstroke and dehydration
Red warning: temperatures across southern England could reach 38C by Wednesday this week
The Met Office has this morning issued a Red heat warning for Croydon and much of southern England and parts of Wales for later this week.
A Red warning is the most severe level of alert which indicates dangerous weather is expected with a high likelihood of risk to life.
“Temperatures will increase significantly in the next few days with the potential for 38 or 39C by Wednesday and Thursday,” according to the BBC.
The extreme hot weather could also lead to failures of critical national infrastructure, such as power outages or roads and rail lines being closed.
“In situations where a red warning is issued, the Met Office advises people to avoid travelling where possible and to follow the advice of the emergency services and local authorities.”
The St John Ambulance has issued a set of first aid advice for coping in the kind of heat we are being told to expect this week.
Dr Lynn Thomas, the medical director of St John Ambulance, said: “Knowing how to spot the symptoms and treat common heat-related conditions such as heat exhaustion, heatstroke, sunburn and dehydration can be vital in helping people look after themselves and others, as well as preventing avoidable trips to hospital.”
Heat exhaustion
Long periods in the sun can lead to heat exhaustion, which is caused by a loss of salt and water from the body, usually through excessive sweating. It develops slowly and usually happens to people who aren’t used to hot, humid weather. If you’re at a festival or outdoor event and it’s very hot, it’s easy to develop heat exhaustion.
These are typical symptoms:
- Headache
- Dizziness and confusion
- Loss of appetite and feeling sick
- Sweating with pale clammy skin
- Cramps in the arms, legs and stomach
- Fast, weakening pulse and breathing.
To treat heat exhaustion, move the person out of the sun, into shade. Help them to lie down in a cool place and raise their legs. Give them lots of water to drink or isotonic sports drinks. Check their breathing, pulse and responsiveness.
Suggest they get medical advice. Call 999/112 if you are concerned.
Heatstroke
Heatstroke should be suspected when someone becomes unwell with altered behaviour or reduced consciousness in hot conditions, particularly if they are very hot.
The initial first response for this is:
Shade: get them out of the sun or away from the heat source
Strip: take all extra layers off the person, ideally down to their underwear
Spray: spray misted water over the patient or pour cool water over them
Fan: waft air across them with a fan to promote evaporation
Heatstroke can be life-threatening. If someone is unconscious, fitting, or getting worse, call 999 immediately. If the patient becomes unresponsive, check their breathing.
Sunburn
It’s important to avoid too much exposure to the sun by covering up with clothing, staying in the shade and applying high-factor sunscreen. Most sunburn is mild, but in severe cases the skin can become damaged, turn lobster red and blister. They may also develop heat exhaustion.
Symptoms of sunburn include:
- Reddened skin
- Pain in the area of the burn
- There may be blistering.
First aid: St John Ambulance offer advice on how to avoid becoming unwell in extreme heat
To treat sunburn, move the person out of the sun, into shade. Cover the skin with light clothing. Give them cold water to sip.
Cool the skin with cool water for 10 minutes.
Apply aftersun cream or spray, or a perfume-free moisturiser to soothe mild sunburn.
If there are blisters, advise that they see a healthcare professional.
Treat any symptoms of heat exhaustion or heatstroke and get medical help.
Dehydration
Dehydration happens when someone loses more fluid than they take in, especially if it’s really hot outside, so make sure you’re sipping lots of water at regular intervals.
There are four key things to look for:
- Headaches and light-headedness
- Dry mouth, eyes and lips
- Passing only small amounts of dark urine
- Muscle cramps.
To treat dehydration, move the person out of the sun, into shade. Help them to sit down and give them plenty of water to drink. Giving them an oral rehydration solution to drink will help replace minerals which they’ve lost – you can buy this in sachets from any pharmacy.
If they have any painful cramps, encourage them to rest, help them stretch and massage their muscles that hurt.
Keep checking how they’re feeling – if they still feel unwell once they’re rehydrated then encourage them to see a healthcare professional straight away.
If left untreated, someone with dehydration can develop heat exhaustion, which is more serious, so it’s important to make sure they rehydrate themselves as soon as possible.
“Keeping well-hydrated, staying in the shade during the hottest part of the day and applying a high‑factor sunscreen regularly are all straightforward ways to reduce the risk of heat‑related illness,” Dr Thomas says. “Wearing a cap or a sunhat in the sunshine is also advisable.
“Finally, remember that even if it’s not direct sun exposure, your body can still be affected by the heat.”
For much more information about heat-related conditions visit https://www.sja.org.uk/get-advice/
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