A heat wave sweeps through the UK

Whilst it is great to see the sun, and consistently too, we need to be very aware of the dangers of a heat wave. It is true to say that the UK is not used to this kind of weather, and previously we saw a sharp rise in deaths during the heat wave in 2006, with an estimated 75 extra deaths per week for each degree of increase in temperature.

Part of this rise may be attributable to air pollution making respiratory conditions worsen, but another main contributor is the effect of heat on the cardiovascular system. The body normally cools itself by sweating. When the ambient temperature is higher than the skin temperature, the only effective heat-loss mechanism is sweating.

Therefore any factor that reduces the effectiveness of sweating such as dehydration, lack of breeze, tight-fitting clothes or certain medications can cause the body to overheat. Temperature control and the ability to sweat can be impaired in the elderly and the chronically ill. Young children produce more metabolic heat, have a decreased ability to sweat and have core temperatures that rise faster during dehydration.

The main causes of illness and death during a heat wave are respiratory and cardiovascular diseases. In order to keep cool, large quantities of extra blood are circulated to the skin. This causes strain on the heart, which for elderly people and those with chronic health problems can be enough to precipitate a cardiac event such as heart failure. Sweating and dehydration affect electrolyte balance.

For people on medications that control electrolyte balance or cardiac function, this can be a risk. Such drugs include vasoconstrictors, antihistamines, drugs that reduce renal function, diuretics and blood pressure medication.

Heat Related Illnesses:

Heat Cramps- caused by dehydration, often following exercise

Heat Rash – Small, red and itchy

Heat Oedema – mainly in the ankles due to fluid retention

Heat Syncope – dizziness & fainting, due to dehydration, cardiovascular disease and certain medications.

Heat Exhaustion – is more common. A result of water or sodium depletion, causing malaise, vomiting and circulatory collapse, occurring when the core body temperature is between 37C and 40C. Left untreated it may evolve into heatstroke.

 Heatstroke – This can become a point of no return when the body`s thermoregulation mechanism fails. This leads to a medical emergency, with symptoms of confusion, disorientation, convulsions, unconsciousness, hot dry skin and a core body temperature exceeding 40C for between 45 minutes and eight hours.

Whatever the underlying cause of heat-relating symptoms, the treatment is always the same – move the person to somewhere cooler and cool them down.

High Risk Factors:

Certain factors do increase an individual’s risk during a heat wave:

Older Age – especially women over 75 years, or those living alone who are socially isolated or in a care home.

Chronic or Severe Illness – heart conditions, diabetes, respiratory or renal insufficiency, Parkinson`s disease or severe mental illness. Drugs prescribed for this group of people often affects their ability to sweat making them more vulnerable.

Inability to Adapt Behaviour – having Alzheimer`s, a disability, being bed bound, too much alcohol, babies and the very young.

Environmental Factors – living in urban areas, south facing flats, being homeless, activities or jobs that are in hot places or outdoors and include high levels of physical exertion.

Protection:

The key message for preventing heat-related illness and death is to keep cool:

·        Try to stay out of the heat between 11.00am and 3.00pm

·        If you have to go out walk in the shade, apply sunscreen and wear a hat

·        Avoid extreme physical exertion

·        Wear light, loose-fitting clothes

·        Have plenty of cold drinks like water of juices.

·        Avoid caffeine and alcohol

·        Eat cold foods, particularly salads and fruit with high water content.

·        Take cool showers and baths as often as you can.

·        Sprinkle water over the skin or clothing, or keep a damp cloth on the back of your neck. Especially good for babies and young children.

·        Keep a thermometer at home to keep a check on temperatures.

·        Use fans in the bedroom at night.

·        Keep bowls of water in the room, as they evaporate they help cool the air.

·        Keep an eye on the isolated, elderly, ill, and the very young – helping them to keep cool.

·        Do not leave the elderly or babies or young children alone in a stationary car.

·        Be alert and call a doctor or social services if someone is unwell or further help is needed.

The Heat wave Plan:

A heat-Health Watch system is operating in the UK from 1^st June to 15^th September each year. During this period the met office may forecast heat waves, and categorise them according to the danger level as set out below. A plan is then introduced into our general daily living to help keep us safe – into our schools& colleges, the NHS, the police- with clear guidelines as to action to be taken.

LEVEL 1 – SUMMER PREPAREDNESS. Long term planning all year. Identifying high risk individuals, installing thermometers, identify cool areas, increase awareness. External shading, water features, reflective paint.

LEVEL 2 – 60% RISK OF HEAT WAVE IN 2-3 DAYS. Alert and readiness in care homes and hospitals. Monitor indoor temperatures four times a day, prepare cool areas, ensure sufficient staffing, identify high risk people, sufficient cold water and ice. Public media messages, increase advice to health and social care workers, have visitor/phone call arrangements in place for high risk people.

LEVEL 3 –HEAT WAVE TEMPERATURE REACHED IN ONE OR MORE REGIONS. Heat wave action in care homes and hospitals. Maximise external shading and night-time ventilation, ensure cool areas do not exceed 26C, provide regular cold drinks. Media alerts about keeping cool, visit/phone high risk people, look out for neighbours, reduce unnecessary travel, review safety of public events.

LEVEL 4 – EMERGENCY- HEAT WAVE FOR FOUR OR MORE DAYS IN TWO OR MORE REGIONS.

So the messages are very clear. We are currently on a level 3 alert in the UK – so we all need to be taking measures to keep ourselves safe, particularly the young and old.

 Also do not forget your pets- dogs should not be exercised during the heat of the day, and ensure all pets have access to plenty of clean fresh water and shade – and some of our paler friends should even wear sunscreen!