Sun, Fun and Heat Related Illness
A few months ago I wrote about a heatstroke my wife suffered and how useful my training (25 years ago) in CPR turned out to be. I remembered enough to start her breathing again quickly and called the local doctor (the Mexican ambulance never came). I continue to advise people to take a First Aid and CPR course. You never know when you may need it.
The American Heart Association offers a website that will give you the location of the nearest classes on the basis of your zip code.
As a good Blog and Desi-critic, I started up the old search engine and began to research the heat-related illnesses of heat exhaustion and heat stroke. They are, I learned, more prevalent and more dangerous than we tend to know since they are not as popular as heart attack, diabetes, cancer and all those telethon, TV-ad campaign diseases. Like heart attack and some other serious diseases, they are preventable. They are also treatable. However, if they are not prevented and not rapidly treated they can cause serious problems or death.
With the hot months coming (let alone global warming) children will be playing hard in the sun, athletes, runners and players of various hot sports will be doing their things. They are at risk.
The elderly, those with serious diseases and those whose immune systems are impaired are also at risk. People living in hot climates may be more acclimated but are still at risk during exercise, stress and illness.
There are two basic varieties: exertional and classic. An excellent article on emedicine.com for emergency physicians by Dr. Jason Hoppe explains the types,Heatstroke traditionally is divided into exertional and classic varieties, which are defined by the underlying etiology, but are clinically indistinguishable.
Exertional heatstroke typically occurs over hours in younger athletic patients who exercise at elevated temperatures for a sufficient period of time to cause the rate of heat production to exceed the capacity of the body to dissipate heat. Classic heatstroke more commonly develops during heatwaves when air temperatures exceed 102.5°F (39.2°C) for three or more consecutive days in older or debilitated patients, who are unable to avoid extreme environmental conditions.
In both cases, thermoregulatory mechanisms fail if the stress becomes too great, which results in accelerated hyperthermia with an increased expression of heat shock proteins, an exaggerated acute-phase response, and end-organ dysfunction.
The problems can be avoided by acclimatizing the body to the hot temperatures and the need for sweating, increasing fluid intake and increased cardio-vascular performance. However there is no acclimating "... in chronically-ill patients or patients with cardiovascular disease. Patients on medications that cause salt and water depletion or impair physiologic cardiovascular responses are at an increased susceptibility to heat injury".
The frequency of the problem in the U.S. alone is shocking,... According to the Centers for Disease Control and Prevention (CDC) from 1979-2002, a total of 4,780 heat-related deaths in the United States were attributable to weather conditions and that, during 1993-2002, the incidence of such deaths was 3-7 times greater in Arizona than in the United States overall. The exact number of persons seeking treatment for heat-related disorders is not recorded but reaches the thousands.
There is a PDF file for download from the American Academy of Family Physicians on Managing Heatstroke.
The level of mortality in those who suffer heatstroke, as did my wife, is said to be 10-70%. Waiting two hours or more for medical treatment results in the most deaths.
Back to learning CPR: I was there and it came back to me so she was treated instantly and her breathing restored quickly. That was luck. I, then, neglected the important treatments that should have been started long before she reached the point of heatstroke. The reason: I did not recognize the clear signs of heat exhaustion and, after CPR, did not know to re-hydrate her and cool her body immediately. The local, Mexican doctor prescribed re-hydration and, if he had been American, removal to an air conditioned area, and keeping her body wet to help evaporative cooling. In many cases the problem is totally preventable: don't win the 28k marathon on the hottest day of summer, give the kids drinks and force a time out once in a while in the shade or the pool, make sure the sick and elderly are spending time in AC and not locked in apartments with the fear of crime in American cities.
When you see those people spraying water or offering drinks to runners, they aren't just making them happy. They are saving lives.
A very clear article on causes, symptoms and treatment is provided by Medicine Plus from the National Library of Medicine and the National Institute of Health on Heat Emergencies. I seriously suggest going to the site, printing a copy and sticking it on the refrigerator for the coming hot season. This article is not highly technical, is readable and easily used in an emergency.The following are common causes of heat emergencies:
- High temperatures or humidity
- Prolonged or excessive exercise
- Excess clothing
- Alcohol use
- Medications, such as diuretics, neuroleptics, phenothiazines, and anticholinergics
- Cardiovascular disease
- Sweat gland dysfunction
More lists of symptoms of heat exhaustion and heatstroke follow along with first aid, things NOT to do, when to call for emergency medical help, and ways to prevent the problem in the first place.
- Wear loose-fitting, lightweight clothing in hot weather.
- Rest frequently and seek shade when possible.
- Avoid exercise or strenuous physical acitivity outside during hot or humid weather.
- Drink plenty of fluids every day. Drink more fluids before, during, and after physical activity.
- Be especially careful to avoid overheating if you are taking drugs that impair heat regulation, or if you are overweight or elderly.
- Be careful of hot cars in the summer. Allow the car to cool off before getting in.
In the UK the National Health Service is concerned enough to provide a 24 hour direct number (ph0845 4647 24hrs in UK) and an interactive site.