PASSION FOR PETS
Every year we have cases of dogs ( rarely cats) presented with hyperthermia. These dogs can present with internal temperatures as high as 110 oF. The normal temperature of the dogs is listed as 100 to 102.5 oF. The temperatures outside have been very hot and with a high humidity, evaporative cooling is minimal. The dog does not have apocrine glands throughout the skin ( some in the foot pads) and does not have the ability to cool off by perspiration. The main cooling mechanism is through panting where the internal heat is exhaled from the upper airways. When the air temperature is high, this cooling technique does not work as well.
The dog typically has a hair coat that acts as an insulation to the cold AND heat, but if the inside or core temperature exceeds what the animal can regulate via panting (or drinking!) then the body temperature can steadily go up. I call this ( from what I learned in pig medicine) malignant hyperthermia. As the temp goes up, tissues are damaged which results in more elevation of body temp…and on!. When the temperature gets high, damage to tissues including the brain, can result in permanent damage and even death.
Treatment is determined by the status of the patient. Sometimes just bringing the temperature down results in a normal response. Sometimes intravenous fluids, cortisone and other medications are needed. Cool water rinsing is generally adequate, while topical rubbing alcohol has been used ( it evaporates fast to enhance cooling). Caution should be used with the alcohol as it it toxic if too much is absorbed, and too rapid of a “cooling” event may result in hypothermia ( low temperature). I have seen this especially in small patients.
Common sense prevails when I recommend that prevention is the best approach!!! For the first advice— DO NOT leave your pet in the car under any circumstances. Most of the animals that have died from hyperthermia have been left in the car … even on a moderate day the sun can cook the inside of the car. Since activity elevates the core body temperature, it is best to allow exercise during the early or late parts of the day when it should be cooler. Having fresh cool water available is very important. Even a small pool may help with some animals. I recommend body clipping certain breeds of dogs to prevent insulating the heat within.
In the dogs that have too much body fat ( an additional insulator) it is wise to plan a weight loss program. Even when we do everything to prevent hyperthermia, it can still happen. Excitement can result in behavior that raises the body temperature… prevent the event.
If the patient loses responsiveness, mobility, coordination or is panting at a stress level, it is best to present it to the veterinarian as soon as possible. A rectal thermometer is usually best for gauging the body temp. Too high if a temperature can result in permanent damage or even death… be aware of the possibilities. Prevention is the best measure for “hot dogs”.