How EMS Crews Can Beat the Heat in a Changing World

Another record-breaking summer of extreme heat incidents challenges America’s EMS providers to keep up with demands for emergency care for patients suffering from hyperthermia, heat exhaustion, and heat stroke.

In Phoenix, Ariz., Fire Department and EMS personnel have implemented a protocol for immersion therapy—putting heat-impacted patients in waterproof bags, which are then filled with ice or cold water, to quickly cool them down. This has been done for years in hospitals and by the military—but is now becoming standard practice for EMS in places like Phoenix, the nation’s hottest large city, which had 31 days of 110 degrees plus in 2023. In that year, Maricopa County, which includes Phoenix, had 645 heat-related deaths.

In March of this year, Arizona hired the first state Chief Heat Officer, epidemiologist Dr. Eugene Livar, to address the impacts of extreme heat statewide. In that role he oversees the implementation of Gov. Katie Hobbs’ Extreme Heat Preparedness Plan. Officials are discouraging hikes and other strenuous physical activity on hot days except in early morning hours, even closing some hiking trails, and making sure cooling stations are accessible to the public day and night, with a transportation hotline to obtain free rides.

Giving heat safety tips to the public and checking up on vulnerable populations thought to be at risk for heat issues, including frail elders and the unhoused, may become increasingly part of the responsibilities for EMS services in a time of climate change.

An Additional Layer of Stress

When contacted for this article, Selena Xie, President of the Austin-Travis County EMS Association and a practicing paramedic, says it was over 100 degrees in Austin, with projections for high temperatures to reach that level for five of the subsequent seven days.

“It is affecting us a lot,” she says. The heat really does add an additional level of stress for EMS providers.

“I think there is science that says that folks need time to acclimate to heat and it takes a few weeks to get used to how hot it is,” Xie says. “But we had this kind of freak heatwave in May, and then we had a lot of people over Memorial Day who were really struggling with the heat.”

With EMS facing 20 percent staff vacancies, resources are spread more thinly as call volumes are going up, she says. “I also think we are running our crews harder than is probably healthy, and we really have to watch that. Our crews feel the work is harder in the heat. A lot of apartment complexes don't have elevators and so they're having to hump a bunch of equipment up the stairs, and working on patients outside in the heat.”

Xie herself has answered emergency calls for people who got overwhelmed just walking to their mailbox and back. Another patient got locked out of his house after going out for a smoke, was left outside for maybe 15 minutes, and thought he was having a stroke because of the heat.

She said that an outdoor training scheduled for Austin’s EMS staff had to be postponed, spilling over into warmer weather.

“We were supposed to do it when the weather was cooler, but we had to delay the training, so now we're doing it in the summer. We've set up parameters about how long and when they can actually do the outdoor training, because it's just so hot now.” These are important skills that staff need to learn, but the timing has become a problem.

“I guess most of us down here in Texas are pretty used to the heat, although it has obviously gotten worse recently,” says James Monks, a paramedic and clinical specialist with Austin-Travis County EMS. “Personally, I drink a lot of water. Most of us do. That’s a big thing—making sure you’re hydrated.” His agency’s uniform policies allow wearing shorts and short-sleeved shirts—as little clothing as necessary to maintain a professional appearance. But Monks said he’s not ready to start wearing shorts on the job.

“We’re fortunate that we get a decent amount of time at the (air-conditioned) hospital to finish our reports after we drop off a patient. Obviously, we want to minimize as much as possible the time that we’re spending outside when we’re not actively treating a patient on scene or doing something else that requires us to be out in the elements.” Heat can exacerbate multiple other conditions for patients, and trying to keep both patient and provider out of the heat is a challenge, he says. “But I think most of us do a pretty good job.”

Monks said he often sees heat exhaustion cases on the job. Heat stroke is less common but still happens. “Most of our crews are seeing three or four people a day for heat-related issues.” They follow agency protocols for preventing heat exhaustion from escalating into heat stroke. That may include applying ice packs or getting cold moisture onto the patient’s skin to help with the cooling process, moving them to air-conditioned spaces, and providing cold intravenous fluids with electrolytes.

“If someone is in heat stroke, we want to do immersion therapy in cold water,” Monks says. In the past that might have been an ad-hoc response, such as picking up a child’s inflatable swimming pool at the nearest store and then covering the patient in bags of ice in the kiddie pool. But it worked. Now all of the agency’s EMS commanders are carrying ice coolers and body bags into the field.

What Are We Talking About?

Hyperthermia, a condition where the body has become too warm and can’t cool itself by natural means such as sweating, can take several forms. Symptoms include heavy sweating, fatigue, and a rapid pulse, as well as feeling sick or irritable. Heat-related syncope, cramps, and rash can also occur. Heat exhaustion, often defined by cold, pale, clammy skin, a fast, weak pulse, nausea, vomiting, and a feeling that one might faint, may present a core body temperature pushing toward 104 degrees.

Heat stroke is a more severe and life-threatening escalation of heat exhaustion and it can cause internal organs to fail if steps are not taken to promptly lower the body temperature. Heat stroke is often accompanied by altered mental status, including slurred speech, confusion, seizures, and loss of consciousness. Hot, red, dry skin (without sweat) is another key sign. People with exertional heat stroke, seen after working or working out in the heat, maybe sweating but are still unable to effectively dissipate the heat.

The “Heat-Related Illness EMS Activation Surveillance Dashboard” was launched in 2023 by the U.S. Department of Health and Human Services’ Office of Climate Change and Health Equity, in partnership with the National Highway Traffic Safety Administration. It maps EMS responses to heat-related illness across the country, by state or county, updated weekly on a rolling basis. EMS agencies may want to use it to keep track of larger trends and of how bad things could get in their locale.

A Focus on Prevention

The name of the game for EMS crews is prevention, says Puneet Gupta, MD, FACEP, an emergency physician in Los Angeles and spokesperson for the American College of Emergency Physicians. “If they are going to be working out in the heat, as search-and-rescue teams, or working with firefighters, their number one goal is to keep themselves safe so they can take care of the patients.”

Dr. Gupta emphasized the process of acclimatization to warm weather through engaging in exertional activities in hot weather conditions when the summer season begins, devoting an hour or two to exertion in a hot ambient environment every other day over the course of 10 to 14 days. This can result in physical adaptation that reduces heat-related physiological stress by up to 20 percent, thanks to increased plasma volume and sweating capacity.

He recommended setting up a water station right inside the EMS facility. “Say to staff, ‘We need you to consider this part of your schedule—to make sure you’re hydrated before we send you out in the field.’” Also, make sure the ambulance’s air conditioning is turned on when out on a call.

Dr. Gupta noted that traditional approaches to heat stroke have recommended putting ice packs (like blue freezer bags) near a heat stroke patient’s groin and armpits in order to cool them. “We’ve found out more recently that this is not the best approach.” Wilderness Medicine Society guidelines say it’s better to put the ice on the palms and soles of the feet and near facial cheeks in order to get the fastest cooling response from ice packs.₁

Another tip offered by Dr. Gupta, “Be aware that when you have a psychiatric patient and it’s hot outside, the heat is going to make them irritable. Try to get them somewhere cooler and give them water before attempting to calm them down.” When overseeing mass gatherings like festivals and concerts in hot weather, make sure that their medical action plan includes cooling and water stations. Also, be aware that recreational drugs like MDMA can cause the body to rapidly overheat, he says.

Mark Liao, MD, an emergency medicine doctor in Indianapolis, IN, and medical director of its local EMS, agreed that it is important for ambulance crews to take care of their own health in hot conditions, making sure they don’t become patients. “That can be challenging for EMS staff who are used to living on energy drinks, showing up for work dehydrated, and keeping irregular sleep schedules, which can also put them at greater risk of heat reactions. It’s important to take the lessons we’ve learned from taking care of others and make sure we apply them to ourselves.”

For instance, he says, remember that the effects of heat stress are cumulative. “You’ve got to get rid of that heat whenever possible. Sleep in air conditioning. Take a cold shower.” Not cooling off at night increases heat risk for the following day. Flu medications and anti-cholinergic drugs don’t help when it comes to treating heat stress in the field and can even inhibit the ability to sweat, he says. “Be mindful of how far you push yourself, and if you need to take a break during a shift on a hot day, your supervisors need to understand that.”

There is still a lot of confusion in the medical field about the warning signs of heat stroke, Dr. Liao said. It’s important to bear in mind the differences between exertional heat stroke in otherwise healthy adults, who are still sweating even though they’ve tipped the body’s response to overheating, and the kind that happens in elderly, frail or chronically ill patients with pre-existing medical conditions, who are more likely to present the red, hot, dry skin.

“You have to have an instinct for suspected heat stroke. Think about their history, their presentation, and don’t rely on forehead temperature measures,” Dr. Liao says. The heat stroke needs to be treated aggressively first, then get them to the hospital. “My final piece of advice, talk to your medical director about how your agency can implement heat protocols.”

What Does the Future Hold?

As climate change worsens, we can expect more extreme heat events. “We’ll have to see what happens in the next 10 to 20 years,” James Monks noted. “But I think this industry of EMS, which is relatively young in the public safety sphere, has continually proven that it wants to advance and move forward,” he says.

“Regardless of whatever issues we face, we need to make sure we’re bringing the best care that we can to our patients. I think that’s the most you can expect of anybody. I think we must always hold ourselves up to that standard.”

Reference

1. Eifling KP, Gaudio FG, Grisson CK. Wilderness Medical Society Clinical Practice Guidelines for the Prevention and Treatment of Heat Illness: 2024 Update. Wilderness and Environmental Medicine. 2024; 35(1):suppl.