Editorís note: We have a guest columnist this month. See below for more information on Dr. Hutchison.August is here and spring is in our rearview mirror. That means more time hiking, driving and enjoying the outdoors with our canine sidekicks. But we should all remember to be mindful of the potentially lethal effects that excessive heat has on our animals.Excess heat buildup in our canine companions begins with heat exhaustion, which happens as a dogís temperature rises from a normal 101∞-102∞ F and starts creeping toward a dangerous 105∞ F. Under these conditions, careful observers may note excessive panting, drooling, restlessness and a decrease in mental awareness. Unfortunately, these early signs can be really subtle (and frankly, some of you might be thinking, ìThat describes my dog on cool daysî).Canine heat stroke occurs at an internal body temperature of 105∞ to 110∞ F. Without an easy way to get rid of this body heat, heat stroke can occur quickly. Internal temperatures at these levels begin to denature and kill (aka: cook) cells in your dogís body, from the intestines to the heart and brain. Vomiting, diarrhea, respiratory distress, collapse and convulsions are all potential heat-related signs of a clinical emergency; and, if so, immediate action is required to minimize the danger to your pet.Itís easy to take for granted how miraculous our ability to sweat is. Itís also easy to forget that our canine friends donít have this same ability. While dogs do have some sweat glands in their foot pads, their ability to release heat through liquids is mostly limited to their mouths and their ability to pant. So while youíre sweating out of every pore as you climb that mountain trail or romp through the fields, your pooch is mostly utilizing the small surface area of their mouth and are consequently very limited to how they can cool their bodies.Some dogs have additional heat-related challenges to consider. Flat-faced dogs (scientifically known as brachiocephalic breeds) have reduced airflow capacity for heat conduction than the longer nosed breeds. Black dogs are prone to rapid heat absorption from our intense, high-altitude sun. Shaggy or Nordic breeds, ever so popular for their mountain versatility, can quickly overheat in the summer sun. And our portly companions, as jolly as they may be, burn more energy and have thicker layers of insulation to overcome than their slender pack mates. Puppies, senior dogs and those with compromised respiratory or cardiovascular systems should also be considered a higher risk.The dangers of heat arenít just limited to the great outdoors. Car-related heat incidents are always troubling to read about this time of the year. Often, these accidents arise from basic misconceptions of how quickly temperatures inside a closed car can rise to dangerous and even fatal levels. Studies have shown that on a clear summer day, an enclosed vehicleís internal temperature increases an average of 20∞F in the first 10 minutes and over 40∞F after an hour, even with the windows down a bit. Although weíre spared the lengthy heat seasons or the high ambient temperatures that many of the low-landers face, our sun exposure is intense; and outside temperatures, modified by low humidity and clear air, can easily lull one into a false sense of security.In the event that you do encounter a dog suffering from heat stress, itís important to know what to do, as this is a true emergency. First, the animal should be moved to a cooler location. Remember, water conducts heat much more efficiently than air so a cool bath or wet towels placed over the animal, along with cool, directed airflow can quickly halt the rise in internal temperature.Offering drinking water is acceptable if the animal can drink and keep it down. And through it all, have your dogís veterinarian on the phone while preparing for a quick transport to a clinic.It is better to be proactive than reactive, whenever possible ó especially with heat. Make sure your pooch has a shady spot both when out with you as well as in their own backyard. It is best to plan the longer treks for the cooler morning hours. It will save you both from the hottest part of the day (as well as reducing the chance youíll be chased off by afternoon torrents of thunder and hail).When you are providing your pup some extended exertion, make sure to take occasional breaks to cool off. Finally, to all you urban explorers: Donít forget that asphalt in the summer sun has the potential to burn unprotected paws.
Dr. Rob Hutchison is a veterinarian practicing with Dr. Jim Humphries at Home With Dignity, a hospice and end-of-life practice in Colorado Springs. Hutchison has special training as a pathologist, and his wife is also a veterinarian and certified in rehabilitation. www.HomeWithDignity.com
