Sweating Out the summer

It's finally hot in Lyneham. That promised heat wave has finally hit us and, if the predictions are correct, it's here to stay. Welcome as it is, this weather does pose risks. Here we outline the four major heat-related illnesses and what to do if they develop. Remember, the dangers can be cut dramatically by wearing sensible clothing, donning hats, avoiding alcohol and regularly topping up on water.

[ Heat rash | Heat Cramps | Heat Exhaustion | Heat Stroke ]

Heat rash

The symptoms: Tiny bumps surrounded by red blotches on the skin. These can itch intensely, sting or feel prickly; hence the condition's other name - prickly heat.

The cause: Sweat. Excessive perspiration damages cells on the surface of the skin. These cells form a barrier, trapping fluid beneath the skin's surface and causing the bumps. It is these bursting and releasing their moisture that creates the stinging, prickly sensation. Heat rash tends to occur on clothed parts of the body, such as the back, abdomen, neck, groin or armpits.

The dangers: It usually goes away on its own within a few days but in severe forms can interfere with the body's heat regulating mechanism and lead to either heat exhaustion or heat stroke.

What to do: Don't apply ointment or creams - they will clog the skin's pores and prolong the condition. Get out of the sun and into a cool environment, remove as much clothing as possible, particularly from affected areas, and use air, rather than a towel, to dry the skin.

Heat cramps

The symptoms: Brief but severe cramps in the muscles of the arms, legs or abdomen.

The cause: Cramps often hit people who exercise heavily in high temperatures. Profuse sweating strips the body not just of fluid but also of salts (aka electrolytes). Low salt levels make the muscles become hard and tense. Children are particularly susceptible when they haven't had enough fluids.

The dangers: Although cramps can be very painful and make you feel like your limbs are about to snap, they aren't serious.

What to do: Heat cramps are unlikely to need special treatment A cool resting place and lots of fluid is the best medicine, although massaging the affected muscles also helps.

Heat Exhaustion

The symptoms: Excessive sweating, a light-headed or faint feeling, possible blurred vision, tiredness, headache and nausea or actual vomiting.

The cause: Too much heat and not enough fluids (dehydration). The symptoms are early signs that the body's natural cooling mechanism is failing. The body regulates its temperature mainly through sweat evaporation but, when it becomes dehydrated, or in extreme humidity, this process can break down, causing body temperature to rise above its healthy 37°C.

The dangers: As heat exhaustion is only the initial indication that the body is struggling to cool itself, the dangers are not too great. However, if left untreated, it can develop into the much more serious condition: heat stroke.

What to do: While someone suffering from heat exhaustion is not in a life-threatening condition, they can deteriorate quickly, so swift action is needed. Move them out of the sun and into the shade and, if possible, into cool air-conditioned surroundings. Fluids need to be replaced but regular small sips rather than a few massive pintsized gulps are recommended.

Heat Stroke

The symptoms: Many of these are similar to those for heat exhaustion but sufferers also produce little or no sweat, become confused and disoriented, have a body temperature between 39°C and 41°C, develop rapid and shallow breathing and can have fits. It's an extremely serious condition that can result in death.

The cause: Also known as sun stroke and hyperthermia, this is what happens when the body's cooling system has failed and is unable to stop its temperature from rising.

The dangers: Heat stroke is a medical emergency and, if left untreated, the sufferer will slip into a coma, often within minutes, and eventually die. Heat stroke can result in secondary conditions such as heart failure, kidney failure and brain damage, Young children and the elderly have a particularly high risk of developing heat stroke, as do diabetics and people who are obese. However, should the air temperature exceed 40°C it means that everyone is at risk.

What to do: Anyone suffering from heat stroke should be taken to hospital as soon as possible. In the meantime, get them out of the sun as fast as you can, remove their clothing, cover them with a wet sheet or a towel, fan them continually and give them fluids if they are conscious.