Heat Exhaustion vs. Heat Stroke: What's the Difference?

Heat Exhaustion Vs Heat Stroke - What is it and How Do We Manage it This Summer?

Summer marks an important time in the year. The school year has ended; summer activities are on everyone’s radar and summer gatherings bring people of all ages together. What seems like an innocent change in weather comes with an increased risk of heat-related injuries to children. As such, parents need to understand the difference between heat exhaustion vs heat stroke.

What is Heat-Related Illness?

There are many terms people use related to complications from hot temperatures: heat rash, heat-related muscle cramping, heat swelling and similar terms. All of these and more are related to the umbrella term, Heat-Related Illness. What is it you ask? Heat-Related Illness refers to a spectrum of disorders that can range from a minor heat exposure to life threatening condition. These illnesses occur when the body is exposed to excessive heat and can no longer cool itself effectively, leading to a dangerous rise in body temperature. As a result, kids may suffer from a slight transient rash all the way to low blood pressure and altered mental status. 

Mild conditions along this spectrum include heat rash, heat edema (swelling of your extremities), exercise associated muscle cramping and heat syncope (temporary loss of consciousness). Heat Exhaustion and Heat Stroke are both Heat-Related Illnesses and understanding the difference between the two is essential for summertime.

Heat Exhaustion

Heat exhaustion is a moderate illness along the heat-related illness spectrum. It includes a higher core temperature (98.6F-104F) accompanied by symptoms such as thirst, headache, weakness, dizziness and vomiting. Patients are usually dehydrated, and they can also have a fast heart rate (what we call tachycardia in medicine) and low blood pressure (also known as hypotension). The key difference between heat exhaustion and heat stroke is that heat exhaustion may cause no neurological symptoms or only mild, temporary symptoms—such as slight confusion—that resolve with prompt cooling and hydration. 

Immediate treatment includes taking off clothing, moving to a cool area, applying cold compress or taking a cold shower and hydration. Symptoms are reversible; however, if action is not taken quickly, heat exhaustion can progress to heat stroke.

Heat Stroke

Heat stroke is the most severe of the heat-related illnesses. It includes many of the same features seen in heat exhaustion but is distinguished by significant involvement of the brain. As such, patients will have very high temperatures (>105.8F) and altered mental status such as confusion, delirium and/or coma. This is a life-threatening condition that can lead to irreversible organ damage and fatality because of the body’s inability to release heat. Heat stroke can be distinguished by non-exertional (without physical activity) and exertional (associated with physical activity) but both present similarly. What’s important is to start cooling measures while calling 911 to take your child to the hospital. Before going to the hospital, there are proactive measures you can take to help your child. For older children, you can submerge their body in cold water while having a wet towel over their head and neck. For younger children, you can use a high flow fan and wet towels for cooling. When you get to the hospital, some of the treatment may include IV fluids, continuing cooling measures, consistent vital sign monitoring and possible further interventions depending on the severity of the illness.

The Best Medicine You Could Give: Prevention

Preventing heat-related illnesses is the best way to keep your child safe from them during the summer. Remember to: 

• Keep hydrated. For athletes, make sure to hydrate before, during and after outdoor activities. For special needs children, make sure to supplement their fluids, especially if they need tube feeds or extra water
• Avoid going outside during peak times. Going outside in the mornings or the evenings when the temperature is cooler will help to reduce the chances of heat-related illnesses
• Attend your child's annual health/school screening. Preparticipation physicals can help to identify any underlying issues your child may have that could contribute to them being more susceptible to heat
• Have cooling measures and rapid assessment tools nearby such as thermometers, ice towels, cold water tubs and plenty of water

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Dr. Henry-Robert Thomas, MD

PHM Fellow

Dr. Henry-Robert Thomas, MD is a fellow in Valley Children's Pediatric Hospital Medicine Fellowship Program. Originally from New York, Dr. Thomas completed his medical education in Chicago, Illinois and his residency training in Miami, Florida. He believes in a care philosophy of being one of the many people who can take care of the whole patient and their needs within reason so they can continue living the healthy and productive lives we as a community envision for them. To learn more about Dr. Thomas, click here.