One of the most dreaded emergencies a veterinarian sees is heat stroke. Heat stroke is an extreme increase in body temperature from exposure to hot or humid environment or strenuous exercise. This is more common in summer and is often associated with animals being left in a hot car, excessive exercising or being outside unable to get out of sun. Dogs and cats do not sweat like humans, so they do not dissipate heat as well.
Clinical signs of heat stroke include elevation of body temperature, increased heart rate, excessive panting, hypersalivation, abnormal mucous membrane color, disorientation, collapse and death. Once clinical signs are noticed treatment should be initiated immediately.
Certain risk factors can contribute to heat stroke. Animals that are overweight, elderly or have medical conditions such as heart disease or upper airway disease like collapsing trachea or laryngeal paralysis are much more at risk. Also, brachiocephalic breeds such as bulldogs, pugs, shih tzus, and pekingese are more vulnerable to heat due to shorter noses and smaller airways.
Treatment of heat stroke begins with cooling the body with towels soaked in cool water placed on patient, alcohol on foot pads and ear pinna and fans. Ice packs and ice baths should not be used because they can damage skin. The temperature should be monitored during the cooling process and discontinued once temperature reaches 103. Other important treatments include IV fluids, oxygen and antibiotics to fight infection. Once temperature has come down the patient should be monitored for after effects which can occur hours after actual heat stroke. These after effects include coagulation problems, kidney failure, low blood sugar, heart problems and tissue damage to internal organs.
The prognosis for heat stroke depends on the severity and response to treatment. Animals with higher body temperature >108 tend to do much worse. Treatment should be initiated quickly to avoid severe sequela to elevated body temperatures.
This is an emergency that can often be prevented. Animals should never be left in a hot car or confined to small space on hot days. They should be kept in areas with shade and water but preferably inside if temperatures are extreme. Special care should be taken with brachiocephalic breeds, elderly, obese and animals with medical conditions. If heat stroke is suspected treatment should to implemented immediately for best chance of survival.