Heat stroke is an elevation in body temperature to a level beyond which the body’s cooling mechanisms are able to return the temperature to the normal range. Dogs do not have very efficient cooling mechanisms. They are able to release heat mostly through panting and to a lesser extent from foot pad sweating. They cannot sweat very much and can get overheated easily. Normal body temperature for a dog is 100 to 102.5 degrees Fahrenheit. A dog with moderate heatstroke (body temperature up to 105 degrees Fahrenheit) can usually recover within an hour if given prompt first aid and veterinary care. Severe heatstroke (body temperature over 106 degrees Fahrenheit) is usually fatal.
It is a common misconception to believe that here in Arizona we only see heatstroke in the summertime. During the Southwest summers, when temperatures are well over 100 degrees Fahrenheit, no one is outside with their dogs. We see heatstroke much more commonly in the spring time when the temperature is in the mid 80’s and people are trying to get their last outdoor time in before the furnace of summer turns on. The first fatal heatstroke at our clinic this year presented in early April.
A dog suffering from heatstroke will display several signs including rapid panting, bright red gums or tongue, thick sticky saliva, depression, weakness, dizziness, vomiting (sometimes with blood), diarrhea, and non-responsiveness.
If you suspect your dog has heatstroke, you should remove him from the hot area immediately. Try to lower the body temperature by wetting him thoroughly with cool or room temperature water. And if possible, increase air circulation with a fan. Rapid cooling with ice water is not helpful because it causes constriction of peripheral blood vessels. Allow free access to cool water but do not force him to drink. Recheck rectal temperature frequently. Once the body temperature is 103 degrees Fahrenheit, the cooling measures can be stopped. The dog should then be examined by a veterinarian.
The veterinarian will lower the dog’s body temperature (if you have not already done so) and continually monitor the temperature. The dog will be given intravenous fluids and possibly oxygen. He will be monitored for shock, respiratory distress, kidney shut down, heart abnormalities, blood clotting abnormalities, and gastrointestinal distress.
Dogs with moderate heatstroke that receive prompt treatment often recover without complications. Severe heatstroke, however, can cause multiple organ failures.
Prevention of heatstroke in dogs begins with common sense. When the temperature approached 80 degrees Fahrenheit, the dog’s exercise should be restricted. Pets with predisposing conditions, like heart disease, obesity, older age, and breathing problems should stay in the shade when possible. The dogs should never be left in a parked car even for a short period of time. Avoid places like the beach and places with lots of concrete, which can radiate the heat. Be sure the dog has plenty of cool water and shade if outside.
Have a question or a topic you would like to see in the blog? Feel free to send me an email, talk to me at class, or have your trainer forward a message to me.
Mary K. Quinn, DVM
Dogs4Vets Medical Trainer