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Heatwave health pro.qxd

SUPPORTING VULNERABLE PEOPLEBEFORE AND DURING A HEATWAVE Advice for health and social care professionals Extreme heat is dangerous to everyone. During a heatwave,when temperatures remain abnormally high over more than a couple of days, it can prove fatal. Climate change meansheatwaves are likely to become more common in England. In one hot spell in London in August 2003, deaths amongpeople aged over 75 rose by 60 per cent. This factsheet is part of a national programme to reduce the health risks byalerting people to the dangers and encouraging them to plan in advance what todo in the event of a heatwave. Heatwaves can happen with little warning andillness and death can occur within the first couple of days, so it is best to makethe following preparations before high temperatures are forecast. Ideally theseshould be complete by the beginning of June. You should be reading this, and are urged to act on it, if you work, whether asan individual or part of a team, in primary care or social services or are a homecare provider. It offers advice both on caring for people most at risk during aheatwave, and on organising others who provide care. Who is at risk?
There are certain factors that increase an individual's risk during a heatwave.
These include: • Older age: especially women over 75 years old, those living on their own and who are socially isolated, or in a care home.
• Chronic and severe illness: including heart conditions, diabetes, respiratory or renal insufficiency, Parkinson's disease or severe mental illness. Medicationsthat potentially affect renal function, sweating, thermoregulation or electrolytebalance can make this group more vulnerable to the effects of heat (seeAdditional notes on page 8).
• Inability to adapt behaviour to keep cool: having Alzheimer's, a disability, being bed bound, too much alcohol, babies and the very young.
• Environmental factors and overexposure: living in a top floor flat, being homeless, activities or jobs that are in hot places or outdoors and include highlevels of physical exertion.
During extremely hot weather, there is a risk of developing heat exhaustion andheatstroke and other heat-related illnesses including respiratory and heartproblems. In a moderate heatwave, it is mainly the above high-risk groups thatare affected. However, during an extreme heatwave such as the one affectingFrance in 2003, normally fit and healthy people can also be affected.
SUPPORTING VULNERABLE PEOPLE BEFORE AND DURING A HEATWAVE What are the risks? The effects of heat on health
The body normally cools itself using four mechanisms: • radiation in the form of infrared rays; • convection via water or air crossing the skin; • conduction by a cooler object being in contact with the skin; and • evaporation of sweat.
When the ambient temperature is higher than skin temperature, the onlyeffective heat-loss mechanism is sweating. Therefore, any factor that reduces theeffectiveness of sweating such as dehydration, lack of breeze, tight-fitting clothesor certain medications can cause the body to overheat. Additionally,thermoregulation, which is controlled by the hypothalamus, can be impaired inthe elderly and the chronically ill, and potentially in those taking certainmedications, rendering the body more vulnerable to overheating. Young childrenproduce more metabolic heat, have a decreased ability to sweat and have coretemperatures that rise faster during dehydration. Older women appear to bemore vulnerable to the effects of heat than older men, possibly due to havingfewer sweat glands and being more likely to live on their own. The box on page 4 describes the effects of overheating on the body, which in theform of heatstroke can be fatal.
However, the main causes of illness and death during a heatwave are respiratoryand cardiovascular diseases. A linear relationship between temperature andweekly mortality was observed in England in summer 2006, with an estimated 75 extra deaths per week for each degree of increase in temperature. Part of thisrise in mortality may be attributable to air pollution, which makes respiratorysymptoms worse. The other main contributor is the effect of heat on thecardiovascular system. In order to keep cool, large quantities of extra blood arecirculated to the skin. This causes strain on the heart, which for elderly peopleand those with chronic health problems can be enough to precipitate a cardiacevent. Sweating and dehydration affect electrolyte balance. For people on medicationsthat control electrolyte balance or cardiac function, this can also be a risk.
Medicines that affect the ability to sweat, thermoregulation or electrolyteimbalance can make a person more vulnerable to the effects of heat. Suchmedicines include anticholinergics, vasoconstrictors, antihistamines, drugs thatreduce renal function, diuretics, psychoactive drugs and antihypertensives.
• Increased risk of cardiovascular and respiratory illnesses – these cause
the majority of excess mortality during a heatwave.
• Heat cramps – caused by dehydration and loss of electrolytes, often
following exercise.
• Heat rash – small, red, itchy papules.
• Heat oedema – mainly in the ankles, due to vasodilation and retention
• Heat syncope – dizziness and fainting, due to dehydration, vasodilation,
cardiovascular disease and certain medications.
• Heat exhaustion – is more common. It occurs as a result of water or sodium
depletion, with non-specific features of malaise, vomiting and circulatorycollapse, and is present when the core temperature is between 37ºC and40ºC. Left untreated, heat exhaustion may evolve into heatstroke.
• Heatstroke – can become a point of no return whereby the body's
thermoregulation mechanism fails. This leads to a medical emergency, withsymptoms of confusion; disorientation; convulsions; unconsciousness; hot dryskin; and core body temperature exceeding 40ºC for between 45 minutes andeight hours. It can result in cell death, organ failure, brain damage or death.
Heatstroke can be either classical or exertional (e.g. in athletes).
Whatever the underlying cause of heat-related symptoms, the treatment isalways the same – move the person to somewhere cooler and cool them down.
Reducing the risk before a heatwave
Heatwaves can happen suddenly, and rapid rises in temperature affect vulnerable
people very rapidly. Make as much use as possible of existing care plans to
assess which individuals are at particular risk, and to identify what extra help
they might need.
Health and social care providers need to plan ahead to ensure that care andsupport for people at risk can be accessed in the event of a heatwave. Anyone ina high-risk category who is living alone is likely to need at least daily contact,whether by care workers, volunteers or informal carers. Older people, especiallyolder women, people with chronic or serious illness, mobility problems, severemental illness, those who are on certain medications, or those living inaccommodation that is hard to keep cool, may need extra care and support. SUPPORTING VULNERABLE PEOPLE BEFORE AND DURING A HEATWAVE If you are advising, visiting, supporting or caring for someone in their own home,
these are the steps that should be taken before the weather gets hot. Where
possible, involve their family and any informal carers in these arrangements.
• Plant trees or leafy plants to provide shade and cool the air around the
building. Indoor plants also help keep the environment cool. • Check that any south-facing windows, which let in most sunlight, can be
shaded, preferably with curtains with pale, reflective linings. Metal venetianblinds and curtains with dark linings, absorb heat and may make things worse.
• Consider outside shutters, overhead external shade and using reflective paint.
• Check that the person's home or room can be properly ventilated, without
causing any additional health risk, discomfort or security problems. • Consider the possibility of moving the person to a cooler room. People living in
top floor accommodation may be at particular risk as heat rises.
• Check that fridges and freezers work properly.
• Check that the person has light, loose-fitting cotton clothing to wear.
• If you plan to move the person somewhere cooler in the event of a heatwave,
consider what equipment or help you might need. • Check that fans and air-conditioning work properly, and replace appliances
with energy-efficient models. • Check that extra care and support are available if needed.
• Check that the person can contact the primary care team if one of their
informal carers is unavailable. • Check that their care plan contains contact details for their GP, other care
workers and informal carers. • Check that there are adequate arrangements for food shopping to reduce
having to go out in hot weather. If a heatwave is forecast for your region
• Make sure you have taken the steps outlined above.
• Monitor the current situation by checking the Heat-Health Watch level on the
internet (www.metoffice.gov.uk) or listening to local weather news. • Make sure you know what advice to give people at risk. A public information
leaflet with tips on what to do in a heatwave is available from GP practices,pharmacies, NHS walk-in centres, hospitals, care homes, benefit offices andvoluntary organisations. • Suggest that people at particular risk consult their GP about possible changes
to their treatment and/or medication (see Additional notes on page 8). During a heatwave
How to keep out the heat • Keep curtains on windows exposed to the sun closed while the temperature
outside is higher than it is inside. • Once the temperature outside has dropped lower than it is inside, open the
windows. This may require late night visiting. • Water external and internal plants, and spray the ground outside windows
with water (avoid creating slip hazards) to help cool the air.
• Advise them to stay out of the sun, especially between the hours of 11.00am
• Advise them to stay in the shade, wear hats, sunscreen, thin scarves and light
clothing if going outside. How to keep body temperatures down • Ensure that they reduce their levels of physical exertion.
• Suggest they take regular cool showers or baths, or at least an overall
• Advise them to wear light, loose, cotton clothes to absorb sweat and prevent
skin irritation. • Suggest that they sprinkle their clothes with water regularly, and splash cool
water on their face and the back of their neck. A damp cloth on the back ofthe neck helps temperature regulation. SUPPORTING VULNERABLE PEOPLE BEFORE AND DURING A HEATWAVE • Recommend cold food, particularly salads and fruit with a high water content.
• Advise them to drink regularly, preferably water or fruit juice, but avoid alcohol
and caffeine (tea, coffee, colas). • Monitor their daily fluid intake, particularly if they have several carers or are
not always able to drink unaided. Provide extra care • Keep in regular contact throughout the heatwave, and try to arrange for
someone to visit at least once a day. • Keep giving advice on what to do to help keep cool.
As well as the specific symptoms of heat exhaustion and heatstroke, watch outfor signs that could be attributed to other causes, such as: • difficulty sleeping, drowsiness, faintness and changes in behaviour;
• increased body temperature;
• difficulty breathing and increased heart rate;
• dehydration, nausea or vomiting; or
• worsening health problems, especially of heart or respiratory system.
Emergency treatment
If you suspect someone has heatstroke, call 999. While waiting for theambulance: • take the person's temperature;
• if possible, move them somewhere cooler;
• cool them down as quickly as possible by giving them a cool shower, sprinkling
them with water or wrapping them in a damp sheet, and using a fan to createan air current; • encourage them to drink fluids, if they are conscious;
• give them a saline drip and oxygen if they are unwell; and
• do not give aspirin or paracetamol.
Additional notes
Chronic or severe illness People with chronic or severe illness are likely to be at particular risk, includingthe following conditions: • Respiratory disease;
• Cardiovascular and cerebrovascular conditions;
• Diabetes and obesity;
• Severe mental illness;
• Parkinson's disease and difficulties with mobility;
• Renal insufficiency;
• Peripheral vascular conditions; or
• Alzheimer's or related diseases.
SUPPORTING VULNERABLE PEOPLE BEFORE AND DURING A HEATWAVE The following drugs are theoretically capable of increasing risk in susceptibleindividuals. It may be worth carefully reviewing the medication such individualsare taking, and assessing the risks and benefits of any changes to their regime.
MEDICATIONS LIKELY TO PROVOKE OR INCREASE THE SEVERITY OF HEATSTROKE Those causing dehydration or Diuretics, especially loop diuretics electrolyte imbalance Any drug that causes diarrhoea or vomiting (colchicine,antibiotics, codeine) Those likely to reduce renal function NSAIDS, sulphonamides, indinavir, cyclosporin Those with levels affected by dehydration Lithium, digoxin, antiepileptics, biguanides, statins Those that interfere by central action Neuroleptics, serotoninergic agonists with thermoregulation: by interfering with – atropine, hyoscine – tricyclics– H1 (first generation) antihistamines– certain antiparkinsonian drugs– certain antispasmodics– neuroleptics– disopyramide– antimigraine agents – beta blockers by modifying basal Drugs that exacerbate the effects of heat by reducing arterial pressure All antihypertensivesAntianginal drugs Drugs that alter states of alertness (including those in section 4.4 of the British National Formulary) Further information
The Heatwave Plan The full Heatwave Plan can be accessed on the Department of Health website atwww.dh.gov.uk/publications. It outlines the responsibilities of health and socialcare organisations at different stages during a heatwave. NHS Direct Online at www.nhsdirect.nhs.uk can provide additional advice onheatstroke and other heat-related conditions. Information on alert levels The heatwave alert levels will be triggered by temperature thresholds (see Annex 1 in the Heatwave Plan) set according to regional variations. Therefore theMet Office website www.metoffice.gov.uk will be the first place where the alertlevel is available. The alert level will also subsequently be displayed on theDepartment of Health, Health Protection Agency and NHS Direct websites. Information on air quality Regular updates on levels of particulate matter (PM10), sulphur dioxide, nitrogendioxide, ozone and carbon monoxide are available on Teletext (page 156), and atwww.airquality.co.uk (Air Quality Archive), which also offers health advice tothose who may be particularly sensitive to air pollution. Additional information on air quality can be found from: • the freephone Air Quality Service telephone number 0800 55 66 77
• Sky News Air Pollution bulletin
(which normally airs in the evening around 18.45) You can get advice on skin protection during hot weather from the CancerResearch UK SunSmart campaign website at www.cancerresearchuk.org/sunsmart.
SUPPORTING VULNERABLE PEOPLE BEFORE AND DURING A HEATWAVE Crown copyright 2008 First published July 2004Updated April 2008Produced by the Department of Health This title can also be made available on request in Braille, in audio, on disk and in large print.

Source: https://www.lincolnshire.gov.uk/upload/public/attachments/961/heatwave.pdf