Heatstroke is the most severe of the heat-related illnesses, and refers to an elevated body temperature secondary to environmental exposure to heat with secondary organ dysfunction, especially altered mental status. This can occur in exercising or sedentary animals. Other types of heat related illnesses, like heat exhaustion, generally do not result in an elevated body temperature or abnormal organ function.
Factors that may predispose pets to heatstroke include increased environmental heat (such as a hot day or being left in a hot car) or reduced ability to dissipate heat. Dogs cannot control their body temperature by sweating as humans do, since they only have a relatively small number of sweat glands located in their footpads. Their primary way of regulating body temperature is by panting. If something impairs their ability to pant effectively, this can result in heatstroke. Brachycephalic dogs, dog with laryngeal paralysis, or other dysfunction of the airway can suffer from this.
Two common and preventable causes of heatstroke in patients we see in the ER are:
- Animals left inside the car on a warm/hot day
- Animals with pre-existing breathing dysfunction, such as bulldogs, who are exercised on hot days.
SIGNS OF HEATSTROKE & HYPERTHERMIA
- Excessive panting
- Excessive drooling
- Increased body temperature-above 103ยฐ F
- Dehydration
- Rapid heart rate
- Noisy/distressed breathing
- Reddened gums and tongue
- Producing only small amounts of urine
- Vomiting and/or diarrhea, often with blood
- Wobbly, uncoordinated, and weak movements/walking
- Collapse
- Seizures
- Unconsciousness
WHAT IS THE TREATMENT FOR HEAT STROKE?
Hyperthermia is an immediate medical emergency and affected dogs should be treated right away by a veterinarian. Safe, controlled reduction in body temperature is a priority.Intravenous fluids, mild sedation and low concentration oxygen therapy are also commonly used to treat heat stroke. Some patients need to have a breathing tube placed, transfusions, and other more serious interventions if their situation warrants.
However, there are some steps to take right away if you suspect your pet is experiencing heatstroke.
- Remove them from the hot environment, and into the shade or a cool area
- You can accelerate heat loss by placing a fan blowing on the pet, applying room temperature/slightly cool water to the body, or applying wet towels to the body
Do not immerse in water, apply ice water, force the pet to drink, or leave them unattended.
Following these initial steps, any animal with suspected heatstroke should be seen by a veterinarian.
WHAT IS THE PROGNOSIS FOR HEAT STROKE?
The prognosis for dogs with heat stroke depends on how high the body temperature was elevated, how long it persisted, and what the physical condition of the pet was prior to the heat stroke. Previously healthy pets with mild heatstroke can do well with proper treatment. Animals with pre-existing conditions and who experienced more severe heatstroke may have more serious complications. In the worst cases, heatstroke can be fatal. Blood clotting disorders, kidney failure, swelling of the brain, cardiac disturbances, and fluid in the lungs are all possible consequences. Prompt treatment by a veterinarian is the best way to improve prognosis.
PREVENTION
Prevention, however, entails avoiding situations where your dog is exposed to environments or conditions that lead to overheating.
- Never leave your dog (or any pet) in a parked car. Not even for a few minutes. A closed car becomes dangerously hot very quickly.
- Avoid taking your dog outside during the hottest part of the day.
- Do not leave your dog any place that can become too hot or has poor ventilation. Garages rooms, sunny yards, etc can all become dangerously hot.
- Always have plenty of cool, clean water available for your dog.
- Brachycephalic dogs (bulldogs, french bulldogs, pugs, shih tzus etc) have short noses and less ability to lose heat through panting. They need special attention in warm weather and exposure to heat and exercise should be avoided.