Venture Tree | outdoors. gear. life: July 2008

Hey, this summer has been brutal with the high temperatures and humidity. Do you know what heat related illnesses are? Do you know what signs and symptoms of heat exhaustion, heat stroke, or heat cramps? Who is more at risk?

Well I have found some information to help answer the following questions and many more. Be sure to pay real close attention to the details because some of these have similar signs and symptoms. I also found that some of the information to be similar but each had there own specific differences between the four sources that I used.

These blog entry will cover the heat related illnesses topic over view, frequently asked questions about extreme heat, tips for preventing heat related illness, and health and safety tips about heat related illness. The sources for these following articles will be linked in the above order at the bottom of blog.

Heat related illness - Topic Overview

A healthy body temperature is maintained by the nervous system. As the body temperature increases, the body tries to maintain its normal temperature by transferring heat. Sweating and blood flow to the skin (thermoregulation) help us keep our bodies cool. A heat-related illness occurs when our bodies can no longer transfer enough heat to keep us cool.

A high body temperature (hyperthermia) can develop rapidly in extremely hot environments, such as when a child is left in a car in the summer heat. Hot temperatures can also build up in small spaces where the ventilation is poor, such as attics or boiler rooms. People working in these environments may quickly develop hyperthermia.

High temperature caused by a fever is different from a high body temperature caused by a heat-related illness. A fever is the body's normal reaction to infection and other conditions, both minor and serious. Heat-related illnesses produce a high body temperature because the body cannot transfer heat effectively or because external heat gain is excessive.
Heat-related illnesses include:

-Heat rash (prickly heat, which occurs when the sweat ducts to the skin become blocked or swell, and cause discomfort and itching.
-Heat cramps, which occur in muscles after exercise because sweating causes the body to lose water, salt, and minerals (electrolytes).
-Heat edema (swelling) in the legs and hands, which can occur when you sit or stand for a long time in a hot environment.
-Heat tetany (hyperventilation and heat stress), which is usually caused by short periods of stress in a hot environment.
-Heat syncope (fainting), which occurs from low blood pressure when heat causes the blood vessels to expand (dilate) and body fluids move into the legs because of gravity.
-Heat exhaustion (heat prostration), which generally develops when a person is working or exercising in hot weather and does not drink enough liquids to replace those lost liquids.
-Heatstroke (sunstroke), which occurs when the body fails to regulate its own temperature and body temperature continues to rise, often to 105 F or higher. Heatstroke is a medical emergency. Even with immediate treatment, it can be life-threatening or cause serious long-term problems.

Often, environmental and physical conditions can make it difficult to stay cool. Heat-related illness is often caused or made worse by dehydration and fatigue. Exercising during hot weather, working outdoors, and overdressing for the environment increase your risk. Caffeine or alcohol also increase your risk for dehydration.

Many medications increase your risk of a heat-related illness. Some medications decrease the amount of blood pumped by the heart (cardiac output) and limit blood flow to the skin, so your body is less able to cool itself by sweating. Other medicines can alter your sense of thirst or increase your body's production of heat. If you take medications regularly, ask your health professional for advice about hot-weather activity and your risk of getting a heat-related illness.
Other things that may increase your risk of a heat-related illness include:

Age. Babies do not lose heat quickly and they do not sweat effectively. Older adults do not sweat easily and usually have other health conditions that affect their ability to lose heat.
Obesity. People who are overweight have decreased blood flow to the skin, hold heat in because of the insulating layer of fat tissue, and have a greater body mass to cool.
Summer heat waves. People who live in cities are especially vulnerable to illness during a summer heat wave because heat is trapped by tall buildings and air pollutants, especially if there is a high level of humidity.
Chronic diseases, such as diabetes, heart failure, and cancer. These conditions change the way the body gets rid of heat.
Travel to wilderness areas or foreign countries with high outdoor temperatures and humidity. When you go to a different climate, your body must get used to the differences (acclimate) to keep your body temperature in a normal range.

Most heat-related illnesses can be prevented by keeping the body cool and by avoiding dehydration in hot environments. Home treatment is usually all that is needed to treat mild heat-related illnesses. Heat exhaustion and heatstroke need immediate medical treatment.
Review the Emergencies and Check Your Symptoms sections to determine if and when you need to see a health professional.

Frequently Asked Questions (FAQ) About Extreme Heat

1.What happens to the body as a result of exposure to extreme heat? People suffer heat-related illness when the body’s temperature control system is overloaded. The body normally cools itself by sweating. But under some conditions, sweating just isn’t enough. In such cases, a person’s body temperature rises rapidly. Very high body temperatures may damage the brain or other vital organs. Several factors affect the body’s ability to cool itself during extremely hot weather. When the humidity is high, sweat will not evaporate as quickly, preventing the body from releasing heat quickly. Other conditions that can limit the ability to regulate temperature include old age, youth (age 0-4), obesity, fever, dehydration, heart disease, mental illness, poor circulation, sunburn, and prescription drug use and alcohol use.

2.Who is at greatest risk for heat-related illness? Those at greatest risk for heat-related illness include infants and children up to four years of age, people 65 years of age and older, people who are overweight, and people who are ill or on certain medications.
3.What is heat stroke? Heat stroke is the most serious heat-related illness. It occurs when the body becomes unable to control its temperature: the body’s temperature rises rapidly, the sweating mechanism fails, and the body is unable to cool down. Body temperature may rise to 106°F or higher within 10 to 15 minutes. Heat stroke can cause death or permanent disability if emergency treatment is not provided.
4.What are the warning signs of a heat stroke? Warning signs of heat stroke vary but may include the following:
-An extremely high body temperature (above 103°F)
-Red, hot, and dry skin (no sweating)
-Rapid, strong pulse
-Throbbing headache
-Dizziness
-Nausea
-Confusion
-Unconsciousness
5.What should I do if I see someone with any of the warning signs of heat stroke? If you see any of these signs, you may be dealing with a life-threatening emergency. Have someone call for immediate medical assistance while you begin cooling the victim. Do the following:
-Get the victim to a shady area.
-Cool the victim rapidly, using whatever methods you can. For example, immerse the victim in a tub of cool water; place the person in a cool shower; spray the victim with cool water from a garden hose; sponge the person with cool water; or if the humidity is low, wrap the victim in a cool, wet sheet and fan him or her vigorously.
-Monitor body temperature and continue cooling efforts until the body temperature drops to 101-102°F.
-If emergency medical personnel are delayed, call the hospital emergency room for further instructions.
-Do not give the victim alcohol to drink.
-Get medical assistance as soon as possible.
6.What is heat exhaustion? Heat exhaustion is a milder form of heat-related illness that can develop after several days of exposure to high temperatures and inadequate or unbalanced replacement of fluids. Those most prone to heat exhaustion are elderly people, those with high blood pressure, and those working or exercising in a hot environment.
7.What are the warning signs of heat exhaustion? The warning signs of heat exhaustion include the following:
-Heavy sweating
-Paleness
-Muscle cramps
-Tiredness
-Weakness
-Dizziness
-Headache
-Nausea or vomiting
-Fainting
-The skin may be cool and moist. The pulse rate will be fast and weak, and breathing will be fast and shallow. If heat exhaustion is untreated, it may progress to heat stroke. See medical attention if symptoms worsen or last longer than one hour.
8.What steps can be taken to cool the body during heat exhaustion?
Drink cool, nonalcoholic beverages.
Rest.
Take a cool shower, bath, or sponge bath.
Seek an air-conditioned environment.
Wear lightweight clothing.
9.What are heat cramps and who is affected? Heat cramps are muscle pains or spasms – usually in the abdomen, arms, or legs – that may occur in association with strenuous activity. People who sweat a lot during strenuous activity are prone to heat cramps. This sweating depletes the body’s salt and moisture. The low salt level in the muscles causes painful cramps. Heat cramps may also be a symptom of heat exhaustion. If you have heart problems or are on a low-sodium diet, seek medical attention for heat cramps.
10. What should I do if I have heat cramps? If medical attention is not necessary, take the following steps:
Stop all activity and sit quietly in a cool place.
Drink clear juice or a sports beverage.
Do not return to strenuous activity for a few hours after the cramps subside because further exertion may lead to heat exhaustion or heat stroke.
Seek medical attention for heat cramps if they do not subside in 1 hour.
11.What is heat rash? Heat rash is a skin irritation caused by excessive sweating during hot, humid weather. It can occur at any age but is most common in young children. Heat rash looks like a red cluster of pimples or small blisters. It is more likely to occur on the neck and upper chest, in the groin, under the breasts, and in elbow creases.
12.What is the best treatment for heat rash? The best treatment for heat rash is to provide a cooler, less humid environment. Keep the affected area dry. Dusting powder may be used to increase comfort.
13.Can medications increase the risk of heat-related illness? The risk for heat-related illness and death may increase among people using the following drugs: (1) psychotropics, which affect psychic function, behavior, or experience (e.g. haloperidol or chlorpromazine); (2) medications for Parkinson’s disease, because they can inhibit perspiration; (3) tranquilizers such as phenothiazines, butyrophenones, and thiozanthenes; and (4) diuretic medications or "water pills" that affect fluid balance in the body.
14.How effective are electric fans in preventing heat-related illness? Electric fans may provide comfort, but when the temperature is in the high 90s, fans will not prevent heat-related illness. Taking a cool shower or bath or moving to an air-conditioned place is a much better way to cool off. Air conditioning is the strongest protective factor against heat-related illness. Exposure to air conditioning for even a few hours a day will reduce the risk for heat-related illness. Consider visiting a shopping mall or public library for a few hours.
15.How can people protect their health when temperatures are extremely high?Remember to keep cool and use common sense. Drink plenty of fluid, replace salts and minerals, wear appropriate clothing and sunscreen, pace yourself, stay cool indoors, schedule outdoor activities carefully, use a buddy system, monitor those at risk, and adjust to the environment.
16.How much should I drink during hot weather? During hot weather you will need to drink more liquid than your thirst indicates. Increase your fluid intake, regardless of your activity level. During heavy exercise in a hot environment, drink two to four glasses (16-32 ounces) of cool fluids each hour. Avoid drinks containing alcohol because they will actually cause you to lose more fluid.
17.Should I take salt tablets during hot weather? Do not take salt tablets unless directed by your doctor. Heavy sweating removes salt and minerals from the body. These are necessary for your body and must be replaced. The easiest and safest way to do this is through your diet. Drink fruit juice or a sports beverage when you exercise or work in the heat.
18.What is the best clothing for hot weather or a heat wave? Wear as little clothing as possible when you are at home. Choose lightweight, light-colored, loose-fitting clothing. In the hot sun, a wide-brimmed hat will provide shade and keep the head cool. If you must go outdoors, be sure to apply sunscreen 30 minutes prior to going out and continue to reapply according to the package directions. Sunburn affects your body’s ability to cool itself and causes a loss of body fluids. It also causes pain and damages the skin.
19.What should I do if I work in a hot environment? Pace yourself. If you are not accustomed to working or exercising in a hot environment, start slowly and pick up the pace gradually. If exertion in the heat makes your heart pound and leaves you gasping for breath, STOP all activity. Get into a cool area or at least in the shade, and rest, especially if you become lightheaded, confused, weak, or faint.

Tips for Preventing Heat-Related Illness

The best defense is prevention. Here are some prevention tips:
-Drink more fluids (nonalcoholic), regardless of your activity level. Don’t wait until you’re thirsty to drink. Warning: If your doctor generally limits the amount of fluid you drink or has you on water pills, ask him how much you should drink while the weather is hot.
-Don’t drink liquids that contain alcohol or large amounts of sugar–these actually cause you to lose more body fluid. Also, avoid very cold drinks, because they can cause stomach cramps.
-Stay indoors and, if at all possible, stay in an air-conditioned place. If your home does not have air conditioning, go to the shopping mall or public library–even a few hours spent in air conditioning can help your body stay cooler when you go back into the heat. Call your local health department to see if there are any heat-relief shelters in your area.
-Electric fans may provide comfort, but when the temperature is in the high 90s, fans will not prevent heat-related illness. Taking a cool shower or bath, or moving to an air-conditioned place is a much better way to cool off.
-Wear lightweight, light-colored, loose-fitting clothing.
-NEVER leave anyone in a closed, parked vehicle.
-Although any one at any time can suffer from heat-related illness, some people are at greater risk than others. Check regularly on:
--Infants and young children
--People aged 65 or older
--People who have a mental illness
--Those who are physically ill, especially with heart disease or high blood pressure
-Visit adults at risk at least twice a day and closely watch them for signs of heat exhaustion or heat stroke. Infants and young children, of course, need much more frequent watching.
If you must be out in the heat:
-Limit your outdoor activity to morning and evening hours.
-Cut down on exercise. If you must exercise, drink two to four glasses of cool, nonalcoholic fluids each hour. A sports beverage can replace the salt and minerals you lose in sweat. Warning: If you are on a low-salt diet, talk with your doctor before drinking a sports beverage. Remember the warning in the first “tip” (above), too.
-Try to rest often in shady areas.
-Protect yourself from the sun by wearing a wide-brimmed hat (also keeps you cooler) and sunglasses and by putting on sunscreen of SPF 15 or higher (the most effective products say “broad spectrum” or “UVA/UVB protection” on their labels).

Health and safety tips: Heat Related Illness

Warm weather means activities and fun under the sun! Whether you love putting on shorts and feeling the warm outdoors, or find it hot and sticky, everyone must be careful not to let a heat-related illness spoil the day.

Normally, the body has ways of keeping itself cool, by letting heat escape through the skin, and by evaporating sweat (perspiration). If the body does not cool properly or does not cool enough, the victim may suffer a heat-related illness. Anyone can be susceptible although the very young and very old are at greater risk. Heat-related illnesses can become serious or even deadly if unattended.

Preventing Heat-Related Illness
-Dress for the heat. Wear lightweight, light-colored clothing. Light colors will reflect away some of the sun's energy. It is also a good idea to wear hats or to use an umbrella.
-Drink water. Carry water or juice with you and drink continuously even if you do not feel thirsty. Avoid alcohol and caffeine, which dehydrate the body.
-Eat small meals and eat more often. Avoid foods that are high in protein which increase metabolic heat.
-Avoid using salt tablets unless directed to do so by a physician.
-Slow down. Avoid strenuous activity. If you must do strenuous activity, do it during the coolest part of the day, which is usually in the morning between 4:00 a.m. and 7:00 a.m.
-Stay indoors when possible.
-Take regular breaks when engaged in physical activity on warm days. Take time out to find a cool place. If you recognize that you, or someone else, is showing the signals of a heat-related illness, stop activity and find a cool place. Remember, have fun, but stay cool!

Know What These Heat-Related Terms Mean
Heat Wave: More than 48 hours of high heat (90oF or higher) and high humidity (80 percent relative humidity or higher) are expected.
Heat Index: A number in degrees Fahrenheit that tells how hot it really feels with the heat and humidity. Exposure to full sunshine can increase the heat index by 15o F.
Heat cramps: Heat cramps are muscular pains and spasms due to heavy exertion. They usually involve the abdominal muscles or the legs. It is generally thought that the loss of water and salt from heavy sweating causes the cramps.
Heat Exhaustion: Heat exhaustion is less dangerous than heat stroke. It typically occurs when people exercise heavily or work in a warm, humid place where body fluids are lost through heavy sweating. Fluid loss causes blood flow to decrease in the vital organs, resulting in a form of shock. With heat exhaustion, sweat does not evaporate as it should, possibly because of high humidity or too many layers of clothing. As a result, the body is not cooled properly. Signals include cool, moist, pale, flushed or red skin; heavy sweating; headache; nausea or vomiting; dizziness; and exhaustion. Body temperature will be near normal.
Heat Stroke: Also known as sunstroke, heat stroke is life-threatening. The victim's temperature control system, which produces sweating to cool the body, stops working. The body temperature can rise so high that brain damage and death may result if the body is not cooled quickly. Signals include hot, red and dry skin; changes in consciousness; rapid, weak pulse; and rapid, shallow breathing. Body temperature can be very high--sometimes as high as 105oF.

Stages of Heat-Related IllnessHeat-related illness usually comes in stages. The signal of the first stage is heat cramps in muscles. These cramps can be very painful. If you are caring for a person who has heat cramps, have him or her stop activity and rest. If the person is fully awake and alert, have him or her drink small amounts of cool water or a commercial sports drink. Gently stretch the cramped muscle and hold the stretch for about 20 seconds, then gently massage the muscle. Repeat these steps if necessary. If the victim has no other signals of heat-related illness, the person may resume activity after the cramps stop.

The signals of the next, more serious stage of a heat-related illness (often called heat exhaustion) include--
-Cool, moist, pale skin (the skin may be red right after physical activity).
-Headache.
-Dizziness and weakness or exhaustion.
-Nausea.
-The skin may or may not feel hot.
-The signals of the late stage of a heat-related illness (often called heat stroke) include--
-Vomiting.
-Decreased alertness level or complete loss of consciousness.
-High body temperature (sometimes as high as 105oF).
-Skin may still be moist or the victim may stop sweating and the skin may be red, hot and dry.
-Rapid, weak pulse.
-Rapid, shallow breathing.
-This late stage of a heat-related illness is life threatening. Call 9-1-1 or the local emergency number.

General Care for Heat Emergencies
1. Cool the Body
2. Give Fluids
3. Minimize Shock
For heat cramps or heat exhaustion: Get the person to a cooler place and have him or her rest in a comfortable position. If the person is fully awake and alert, give a half glass of cool water every 15 minutes. Do not let him or her drink too quickly. Do not give liquids with alcohol or caffeine in them, as they can make conditions worse. Remove or loosen tight clothing and apply cool, wet cloths such as towels or wet sheets. Call 9-1-1 or the local emergency number if the person refuses water, vomits or loses consciousness.
For heat stroke: Heat stroke is a life-threatening situation! Help is needed fast. Call 9-1-1 or your local EMS number. Move the person to a cooler place. Quickly cool the body. Wrap wet sheets around the body and fan it. If you have ice packs or cold packs, wrap them in a cloth and place them on each of the victim's wrists and ankles, in the armpits and on the neck to cool the large blood vessels. (Do not use rubbing alcohol because it closes the skin's pores and prevents heat loss.) Watch for signals of breathing problems and make sure the airway is clear. Keep the person lying down.

Information gathered from:

http://www.webmd.com/a-to-z-guides/heat-related-illnesses-topic-overview

http://www.bt.cdc.gov/disasters/extremeheat/faq.asp

http://www.bt.cdc.gov/disasters/extremeheat/heattips.asp

http://www.redcross.org/services/hss/tips/heat.html

-Bentley VentureTree Team