This month, we’ve already seen the in human history based on average temperatures across the globe. And while that heat is dangerous to humans, it’s even worse for dogs. Because they can’t sweat, dogs struggle to release heat as efficiently as humans can. In an effort to help our four-legged friends survive this summer, I examined the ways in which dogs can avoid heat-related illness—and what we as pet owners can do if our canine’s temperature rises too high.
What Is Canine Heatstroke?
Heatstroke is a life-threatening condition that occurs when an animal’s body loses the ability to cool itself. The result is organ dysfunction and then damage that could be permanent or fatal.
According to Cornell University’s Canine Health Center, dogs begin to experience heatstroke when their internal temperature .
“If elevated body temperatures are prolonged, they will cause damage to every organ in the body,” the University’s material reads. “Heatstroke commonly leads to acute kidney injury, blood clotting issues and shock.”
Heatstroke can be caused solely by environmental conditions—hot temperatures—or result from a combination of environmental conditions and such as too much exercise.
How Dangerous Is Canine Heatstroke?
A study published in Nature found that out of 905,543 dogs who entered formal veterinary care in the United Kingdom during 2016, . Fifty-six of those dogs (14 percent) died as a result.
That same study found that incidents of dogs suffering heat-related illnesses is increasing year-on-year, something the authors attribute to climate change.
Mortality rates are higher in hotter areas of the world. , for instance, found that 50 percent of all dogs admitted to vets for heat-related illnesses died. A study of records for otherwise healthy dogs treated for heat-related illnesses in the United States found that as a result of heatstroke, or 36 percent. A German study pegged the studied fatality rate for heatstroke in that country at .
What Are Symptoms of Heatstroke in Dogs?
If a dog is or has been exposed to hot temperatures, Cornell says the following signs may indicate that they may be experiencing heat related illness:
- Heavy Panting
- Drooling
- Bloody diarrhea
- Vomiting
- Weakness
- Confusion
- Seizures
- Collapse
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What Heat Risks Do Dogs Experience?
Dogs are at particular risk of heatstroke for two reasons: They can’t sweat like humans, and our best friends are exposed to more extreme heat than we are, even when we share spaces.
Humidity: When dogs pant, they allow moisture to escape from their lungs, reducing body heat. High humidity can halt that process, preventing a dog from cooling itself.
Environmental factors: A study conducted in Alabama found that, on average, dogs experience temperatures 1.3 degrees hotter than those experienced by their owners. Variables like clothing, shade, and distance from the hot ground may contribute.
Hot surfaces: Even in 75 degree ambient temperatures, direct sun exposure can increase the temperature of pavement to 125 degrees or more. That’s hot enough to burn a dog’s paws. In Arizona this month, street temperatures have been measured .
Health: The Nature study found that factors like a dog’s skull shape (brachycephalic, or short-nosed dogs), obesity, and age significantly increased risk of heatstroke.
Hot cars: Across all studies and reports, one factor stands out above all others—dogs left in hot cars are most at risk for heatstroke. A parked car can reach dangerous temperatures in a matter of minutes, even if the windows are down.
What Should You Do if Your Dog Gets Heatstroke?
If you suspect that your dog is beginning to overheat, or if you discover a dog you think is suffering from heatstroke, you need to cool it down immediately.
If possible, first move to shade or an air conditioned environment. Then apply ice, cool water, or other tools directly to the dog’s skin to cool it down as rapidly as possible.
“I use water and ice,” says Joe Spoo, a sporting dog veterinarian located in South Dakota. “With the ice, I’m using it strategically deep in the groin, deep in the armpits, and across the jugular.”
Spoo explains that those areas are closest to major arteries, allowing ice to cool the dog as effectively as possible. He also recommends drenching the dog in cool water, or even placing it in a body of water like a lake or stream, should one be available. If water is in short supply, he says you can soak a towel, t-shirt or similar with a water bottle, and apply that to the same areas.
When I take my dogs hiking or camping during the summer, I throw a cooler or 12-volt fridge in the truck, and keep a few ice packs and jugs of water in that. Even on short outings, where I’m not otherwise packing food and drinks.
Spoo also recommends carrying a thermometer as part of your dog first aid kit, and using that to monitor temperature change in your dog. Normal internal temperatures for dogs run between 100 to 102.5 degrees Fahrenheit. If you’re worried your dog may be overheating, Spoo suggests using a thermometer not just to take a reading, but rather to monitor whether or not the dog is cooling down.
“During heatstroke, the problem is your dog’s internal thermometer is broken,” the vet explains. “The key with heatstroke is that the dog loses the ability to cool itself down. So take its temperature at 5, 10, and 15 minutes, and if you have a temperature that’s climbing or staying the same you have a problem.”
And while Spoo says you need to cool a dog experiencing heatstroke as quickly as possible, you should use that thermometer to keep an eye on its internal temperature, and stop cooling at 103 degrees.
Once you’ve cooled a dog down to a safe level, you need to get it to an animal hospital as fast as possible. There, a vet may administer intravenous fluids, antibiotics, perform a blood transfusion, or otherwise treat any organ damage that may have occurred. But a vet cannot cool a dog any faster or more effectively than you can, so prioritize cooling the dog before transporting it, or make sure you’re able to cool it during transportation.
How Can You Prevent Your Dog from Getting Heatstroke?
Spoo says a good guideline for active dogs is to add together the air temperature and humidity level, and, if the sum exceeds 150, then “it’s a danger zone for most dogs.”
In hot weather, leave your dog in a reliably air conditioned or shaded space, and make sure they have plenty of cool water to drink. Never leave a dog unattended in a parked car.
It’s also important to get to know your dog, and in what conditions they do well or struggle. Temperatures that may be safe for a young, healthy mutt, may be lethal for a senior, overweight, brachycephalic purebred like a bulldog.
But Spoo says this knowledge, and even a mastery of first aid techniques should not be used as an excuse for exposing your dog to danger. “Don’t use this information to push boundaries, and then try to save your dog,” the vet advises.