Ask the doctors: Heat exhaustion, heat stroke require medical intervention
Q: I am 72 years old and in good health. Last fall, I got weak and shaky while working in my yard. It was a hot day, so my son insisted on calling 911. They said it was heat exhaustion, and I got treated on the spot. How is heat exhaustion different from heat stroke?
A: Heat exhaustion and heat stroke are both heat-related illnesses. These conditions range from mild, with symptoms such as heat rash and heat cramps, to more serious. Your son made the right decision to seek immediate medical care. Heat-related illness is dangerous because once the body begins to struggle to stay cool, it can quickly progress to severe illness.
Heat exhaustion is a sign that the body's natural cooling mechanisms are getting overwhelmed. This causes metabolic changes that disrupt normal body functions. Symptoms include the weakness and dizziness that you had. Other symptoms are excessive sweating, fast heart rate, elevated temperature, rapid breathing, thready pulse, muscle cramps, headache and nausea. The skin may show red, itchy blotches of heat rash, or may become paler than normal, cool to the touch or clammy.
Heat exhaustion needs treatment as soon as possible. If you have signs of heat exhaustion, you should move to a cool, shaded area and lie down. Remove or loosen unneeded or tight clothing. You can also cool your skin and head with water or wet towels.
Slowly sip water that is cool, not ice cold. Very cold beverages can cause stomach cramps and may interfere with fluid absorption. If you don't recover within 30 minutes, seek further medical help.
Heat stroke is an escalation of heat exhaustion. It is the most severe form of heat-related illness and is a medical emergency. It occurs when the body's cooling systems are completely overwhelmed and shut down. Symptoms include temperature of 104 degrees Fahrenheit or higher, hot or dry skin that also may be red or flushed, a racing or pounding heartbeat, muscle cramps, vomiting, extreme exhaustion, altered mental state and seizures.
If someone is experiencing heat stroke, call 911. They need immediate medical intervention. In the meantime, move them to a cool, shaded place. As with heat exhaustion, remove or loosen unneeded or constricting clothing.
Try to cool the person down however possible. Put them in cool water; apply cold packs to their neck, armpits and groin; mist the skin with cool water or fan the skin. Do not offer fluids, as they may be unable to safely ingest them. Be prepared to perform CPR in case they lose consciousness.
In a medical setting, cooling measures will continue. Patients will also receive supportive care. This typically includes monitoring vital signs, administering IV fluids and supplemental oxygen, and checking for and addressing complications. The speed of recovery from heat stroke depends on how severe their condition is and how quickly they receive treatment.
• Dr. Eve Glazier is an internist and associate professor of medicine at UCLA Health. Dr. Elizabeth Ko is an internist and assistant professor of medicine at UCLA Health. Send your questions to askthedoctors@mednet.ucla.edu.
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