Why Does Heat Stroke Happen?
Dogs and cats can overheat for multiple reasons.
The most common presentation for heat stroke is a dog that was out for a walk or playing on an extremely hot day who suddenly collapses or starts showing signs of ataxia, or a drunken-type of walk. We can also see overheating that occurs if a pet is seizing for greater than 5 minutes (also called status epilepticus) or if an animal was trapped in a hot car, room, or dryer.
What is Heat Stroke?
The phenomenon known as heat stroke generally sets in when the body temperature approaches or exceeds 106 degrees (normal body temperature for dogs and cats is 99-102 F). When this happens, enzymes and other proteins in the body are unable to function the way they are supposed to and many systems begin to shut down and signs of systemic shock begin to set in. The most common consequences of heat stroke include diarrhea (usually hemorrhagic/bloody) and loss of blood clotting function (coagulopathy).
Treatment and Outlook
Initial treatment entails bringing the body temperature down in a controlled manner with cooled intravenous fluids. Broad-spectrum IV antibiotics as well as replacement of lost clotting factors (often using fresh frozen plasma, a type of blood product) are often used to treat heat stroke. The prognosis for recovery from heat stroke is guarded, meaning that some patients do not survive after being overheated despite our best attempts. However, those that do survive generally make a full recovery without lasting effects.
If your pet is showing signs and has a history consistent with overheating, rapid presentation to the emergency room is paramount.