Summer’s here: Watch for heat illness

Sometimes there is nothing more glorious than a day outside, with the heat of the sun filling your every pore while you participate in an enjoyable activity and you don’t have a care in the world. But there can also be too much of a good thing and too much heat from the sun can bring trouble, possibly even death. Heat can kill, and people need to be aware and alert.

Dr. Scott Knutson, emergency room physician at Trinity Health, said he and the emergency room staff have not yet seen any people experiencing symptoms from heat illness this year, but it’s a big deal. It’s underrated as a health threat, he added, one that kills 175 to 200 people in the U.S. each year.

There are several types of injuries and illnesses that can come from the heat. From minor to major, they include heat rash, sunburn, heat cramps, heat exhaustion and heat stroke.

Heat rash, also known as prickly heat or sweat rash, is when small areas of itchy rash develop minutes to hours after sun exposure or increased sweating, Knutson explained. It happens when sweat obstructs glands, which leads to a leakage of sweat into layers of epidermis, causing an inflammatory reaction. Repeated rashes may provoke a deeper skin reaction, and bacteria on the skin may induce a local skin infection, Knutson said. Most reactions are self-limited and symptoms can be limited with many of the same treatments as for sunburn. If the rash seems to be increasing in redness or there is pain, Knutson said the person should seek further medical advice.

With sunburn, Knutson said there is some thought that one significant exposure to the sun from ages 10 to 28 can lead to skin cancer, Knutson said. High SPF ratings are helpful, he added. Symptoms of sunburn include reddened, painful skin that may or may not blister, Knutson said, and sunburn is caused by ultraviolet burn to the outermost skin layer. Prevention is key for sunburn. Avoiding the sun at peak times, covering your skin and wearing sunscreen are ways to prevent sunburn. Knutson said seeking medical attention is necessary if you have a severe sunburn with extensive blistering and pain and if you experience additional signs of heat illness or injury such as headache, nausea or vomiting, fever dizziness or an altered mental status.

Heat cramps consist of painful cramping of the larger muscle groups like the legs, arms and abdomen. They tend to be caused by an excessive loss of salt through heavy sweating, plus several hours of sustained exertion. Knutson said heat cramps are best treated by moving to a shaded area, massaging the arms or legs to increase circulation, and by drinking salt water or a sports drink or salted food plus fluid.

Symptoms for heat exhaustion include heavy sweating, headache, feeling light-headed, nausea or vomiting, tingling sensations or cramps and a body temperature of 99 to 104 degrees. Its cause comes from dehydration plus excessive salt depletion. Knutson said if you start feeling the symptoms for heat exhaustion, “you are flirting with heat stroke.” Heat exhaustion is a precursor to heat stroke and if heat exhaustion is left untreated, it can lead to stroke. For treatment of heat exhaustion, Knutson recommended moving to a shaded environment, loosen your clothing, drink fluids if you are able and drink one to two liters of fluid, like cold water, over two to four hours. Also, it usually takes a few hours for heat exhaustion symptoms to settle down before you can resume activity, he continued.

“It’s important to go slow (when resuming the activity) because heat exhaustion can recur,” he said.

Heat stroke is a true heat emergency, Knutson said, and when people really start having problems. Heat stroke occurs when the body becomes unable to regulate itself, the sweating mechanism fails and the core body temperature rises, he explained.

Symptoms of heat stroke include elevated temperature that’s often very high; rapid pulse, headache, confusion or altered mental state; loss of consciousness; hot and dry skin even though there is no sweating. Heat stroke can lead to brain damage, kidney failure, liver failure, blood clotting abnormalities and eventually death. Heat stroke may be acute with exertion and/or a high heat index, but may be chronic related to the duration of elevated temperature or heat index.

For immediate treatment of heat stroke, Knutson said to call 911.

“That is an ambulance call, not an ER visit,” he emphasized. It’s also instructed to move the person experiencing heat stroke symptoms to the shade, lower the body temperature as fast as possible, expose skin to enable cooling and use cool water soaks with fanning to increase evaporation or place ice packs on the person’s groin or underarm.

Risk factors for heat stroke are dehydration, acute illness, alcohol use, medications and obesity.

Heat stroke is also sometimes seen in the elderly who are cooped up in their apartment or house for days, Knutson noted. If they’re isolated, don’t have air conditioning or have it turned down, not dressing for the heat, are immobile or are taking certain medications, it may put them at risk for heat stroke.

There are two ways in which to control the risk of heat stroke – rehydration and acclimatization. Water is the best fluid for short activity, Knutson said. Sports drinks are appropriate when the duration of activity is greater than six hours if snacks or meals are not consumed, he continued, and when the duration of strenuous exercise is greater than three hours if snacks or meals are not consumed.

Acclimatization is a physiologic adaptation that occurs in response to heat exposure in a natural environment. It takes 60 to 90 minutes of daily exposure to heat and exercise, Knutson said, and most people will rapidly adjust within the first five days. Most notably, acclimatization results in increased sweating at a lower temperature, which increases the body’s ability to dissipate heat, he added.

Knutson had additional advice for avoiding heat illness and injury, including paying attention to heat index postings in warmer weather; paying attention to the duration of high heat exposure even without significant activity and intensity of work or exercise; paying attention to those around you who may be at risk; and keeping up fluid intake when in the heat for a prolonged period and with exercise. Do not ignore symptoms that develop with heat, either, he added, like nausea, headache or dizziness.

People are pretty good about moderating their exposure to heat and looking after each other, Knutson remarked. This also is not an area that has a high heat index, he added, so we aren’t as susceptible to heat illness or injury as much as people would be in Chicago or somewhere more south.

Knutson said in the emergency room, they see a lot people with kidney failure and dehydration issues.

“Heat exhaustion is difficult to diagnose and distinguish, though,” he said. There were also a fair number of people who experienced heat exhaustion during the 2011 flood, Knutson noted.