About 400 Americans die from heat exposure each year, according to the Centers for Disease Control and Prevention. Heatstroke and heat exhaustion are two common conditions.
Question: Who's at greatest risk?
Answer: Older, sedentary people living in poorly ventilated homes. Seniors don't adjust as well to sudden changes in temperature. They're more likely to have chronic health conditions and to take medications that block perspiration or hurt the body's ability to regulate its temperature, the CDC says. Children under 4, the mentally ill, the obese and people who are ill or taking certain medications are also at greater risk.
The CDC suggests visiting older adults at least twice a day. If they lack air conditioning, take them to cool places such as malls or libraries. Electric fans might make people more comfortable but might not prevent heat injury, says Kathleen Clem of the American College of Emergency Physicians.
Question: What is heatstroke?
Answer: It's a life-threatening condition in which dangerously high body temperatures affect the brain, Clem says. High temperatures can cause cell damage or death in as little as 45 minutes.
Question: What are the symptoms?
Answer: The skin often becomes hot and flushed, according to the "Merck Manual of Medical Information." Heart and breathing rates increase. Pulse is usually rapid. Blood pressure may be very high or very low. Victims may become confused and suffer headaches and nausea. Body temperature usually exceeds 104 degrees, and victims might lapse into a coma.
Question: How easy is it to spot?
Answer: Clem notes that some symptoms — such as impaired judgment or bizarre behavior — may be subtle. About half of heatstroke victims are sweating, although perspiration might stop as the condition advances.
Question: How is it treated?
Answer: Call for medical help. Cool victims immediately with a cold, wet sheet, Clem says. Heatstroke is best treated at a hospital.
Question: What are the long-term effects of heatstroke?
Answer: Body temperature might fluctuate abnormally for weeks, according to the "Merck Manual." The brain might not fully recover, causing personality changes, clumsiness or poor coordination. Victims might be more prone to heatstroke in the future.
Question: How can it be prevented?
Answer: Avoid exercise in hot weather and drink plenty of fluids even after your thirst is quenched. Avoid alcohol, caffeine and high-sugar drinks, all of which may make people more dehydrated.
Question: What is heat exhaustion?
Answer: It's the most common heat-related illness. It's caused when the body temperature rises and victims become dehydrated.
Question: What are the symptoms?
Answer: Victims may be drenched in sweat, according to the "Merck Manual." Body temperature may be high, but generally not above 104 degrees. They may feel faint, dizzy, weak, tired and nauseated and have a rapid heart rate and breathing but low blood pressure.
Question: How is it treated?
Answer: Victims should get out of the heat and drink fluids. Loosening clothing and applying ice packs or taking a cold bath or shower might help, the manual says.
Question: What are the long-term effects of heat exhaustion?
Answer: Victims usually recover rapidly, although untreated heat exhaustion can lead to heatstroke."