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What happens when you get heat stroke? - Douglas J. Casa
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What happens when you get heat stroke? - Douglas J. Casa

 
In 1985, 16-year-old Douglas Casa, ran the championship 10,000 meter track race at the Empire State Games. Suddenly, with just 200 meters to go, he collapsed, got back up and then collapsed again on the final straightaway, with his body temperature at dangerous levels. He had suffered an exertional heat stroke. Fortunately, with immediate and proper treatment, he survived the potentially fatal episode and has since helped save 167 people in similar circumstances. From ancient soldiers on the battlefield to modern day warriors on the gridiron, exertional heat stroke, or sunstroke, has long been a serious concern. And unlike classical heat stroke, which affects vulnerable people such as infants and the elderly during heat waves, exertional heat stroke is caused by intense exercise in the heat, and is one of the top three killers of athletes and soldiers in training. When you exercise, nearly 80% of the energy you use is transformed into heat. In normal circumstances, this is what's known as compensable heat stress. And your body can dissipate the heat as quickly as it's generated through cooling methods like the evaporation of sweat. But with uncompensable heat stress, your body is unable to lose enough heat due to overexertion or high temperatures in humidity, which raises your core temperature beyond normal levels. This causes the proteins and cell membranes to denature, creating cells that no longer function properly and begin to leak their contents. If these leaky cells proliferate through the body, the results can be devastating. Including liver damage, blood clot formation in the kidneys, damage to the gastrointestinal tract and even the failure of vital organs. So how do you diagnose an exertional heat stroke? The main criterion is a core body temperature greater than 40 degrees Celsius observed along with physical symptoms such as increased heart rate, low blood pressure and rapid breathing or signs of central nervous system disfunction such as confused behavior, aggression or loss of consciousness. The most feasible and accurate way to assess core body temperature is with a rectal thermometer as other common temperature-taking methods are not accurate in these circumstances. As far as treatment goes, the most important thing to remember is cool first, transport second. Because the human body can withstand a core temperature above 40 degrees Celsius for about 30 minutes before cell damage sets in, it's essential to initiate rapid cooling on site in order to lower it as quickly as possible. After any athletic or protective gear has been removed from the victim, place them in an ice water tub while stirring the water and monitoring vitals continuously. If this is not possible, dousing in ice water and applying wet towels over the entire body can help. But before you start anything, emergency services should be called. As you wait, it's important to keep the victim calm while cooling as much surface area as possible until emergency personnel arrive. If medical staff are available on site, cooling should continue until a core temperature of 38.9 degrees Celsius is reached. The sun is known for giving life, but it can also take life away if we're not careful, even affecting the strongest among us. As Dr. JJ Levick wrote of exertional heat stroke in 1859, "It strikes down its victim with his full armor on. Youth, health and strength oppose no obstacle to its power." But although this condition is one of the top three leading causes of death in sports, it has been 100% survivable with proper care.

Douglas Casa, Cinematic, heat stroke, exertional heat stroke, exercise in heat, human body, effects of heat on human body, heat, TED, TED-Ed, TEDEducation, TED Ed

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