Heat Stroke in Dogs

Warmer weather is finally here.  No more snow.  Now we must protect our goldens from extreme heat.  Summer days can be very hot and humid.  Our goldens like to run and play and can easily get overheated.  This article will give you some warning signs, early treatments and prognosis if severely overheated.

What are the signs of heat stroke?

Heat stroke is characterized by marked elevation in body temperature (>105.8 F) from exposure to a hot or humid environment (confined in a vehicle, obesity, lack of water or shade, heart disease, seizure disorders, high temperatures and humidity levels) or from strenuous exercise.  Heatstroke occurs due to the body’s inability to dissipate heat effectively.  Instead of sweating, dogs eliminate heat by panting.  They do have sweat glands in the footpads, which help with heat dissipation, but only minimally.  When panting isn’t enough, a dog’s body temperature rises.  This can be fatal if not corrected quickly.

Excessive panting and signs of discomfort indicate overheating in dogs. The dog may be unable or unwilling to move around.  Other signs of heatstroke include drooling, reddened gums, vomiting, diarrhea with or without blood, mental dullness or loss of consciousness, uncoordinated movement and collapse.  Overheated dogs can develop fatal cardiac arrhythmias and seizures.  If not treated quickly, death can occur.

What do you do if you think your dog is suffering from heatstroke?

First thing to do is to remove the dog from the hot environment.  Do NOT give your any medications because they can lead to other problems.  If the dog is conscious, place your dog in the bathtub or find a hose.  Use cool water but not ice-cold water. If you cannot find a hose or cannot get your dog in the bathtub, place towels soaked in cool water on the back.  Do not submerge the dog’s head below water as they can aspirate water and develop aspiration pneumonia. Place your dog in your air-conditioned vehicle and go directly to your veterinarian or the nearest emergency clinic.  Heat stroke can cause many severe problems such as swelling on the brain, kidney failure, intestinal bleeding and abnormal clotting of the blood so treatment must begin quickly.

Your veterinarian will want to hospitalize your dog for prolonged treatment.  Your dog will be given IV fluids to help lower the body temperature and rehydrate the dog from water loss due to excessive panting.  Oxygen may be administered to help your dog oxygenate better. Your veterinarian will want to run some bloodwork to assess organ function and the blood’s ability to clot (CBC, chemistry panel, electrolytes, urinalysis, and coagulation panel).  They may also want to take chest X-rays to assess for pulmonary edema (fluid in the lungs).  Other medications will depend on the results of the diagnostics.  Many of the dogs will develop bloody diarrhea.  Your veterinarian will give your dog gastrointestinal protectants to help prevent further ulceration of the stomach and intestines and antibiotics to prevent spread of bacteria from the intestines. They will monitor your dog’s ECG to assess for any life-threatening heart arrhythmias.

The prognosis for heatstroke varies, depending upon the severity of the presenting signs and the response to therapy.  Delayed admission to the hospital (>90 minutes) and seizure activity were negative prognostic indicators.  Dogs that presented with low blood sugar, blood clotting problems or those that developed kidney failure did worse than those dogs that did not have these signs.  Most dogs with heatstroke will be hospitalized for 1-6 days.  Dogs that survived the first three days, usually did well.

The best medicine is to prevent heatstroke.  Do NOT leave dogs in a car or other confined space on hot or humid days.  Your car’s interior temperature can get too hot for your dog even if the outside temperature is only 70 F (the car’s interior can reach 89 F within 10 minutes).  Keep animals inside on hot and humid days.  Make sure that your dog always has access to shade and water when outside.  Avoid heavy exercise on hot or humid days; walk the dog early in the morning or late at night when it is cooler. This will also help protect their footpads from boiling hot pavement.

Summer is a great time and we enjoy being outside.  But don’t forget to take care of your dog and protect him or her from heatstroke.

Linda Lewiston, DVM. MS