One summer day, while I was working as relief vet at a veterinary hospital, a couple of good Samaritans came in to report a beagle in an open-air convertible car out in the hot parking lot. They said the owner was in the bar and refused to come out to her dog. I went outside to find a frantically panting dog who was quite agitated, hot, and had very red gums… clear signs of heat stress. The poor Beagle did not realize that to save her life, all she had to do was jump out of the totally open convertible (top down, open to the air) car, and may have died there if strangers had not intervened.
We brought her inside and the thermometer quickly shot up to the maximum number that it could register--106 degrees!! We instituted treatment immediately while the police were called. The owner was cited and had to appear in court and pay fines.
I believe it would have been far more productive to set the owner outside in a coat, as her dog was, so that she could experience the reality of the situation for herself so that it would not recur. Yes, the dog did go home with her, although I recommended that she continue to be observed at an emergency clinic overnight. I can only assume that, weeks later, she did not develop anything like kidney failure, intestinal issues, or neurological problems due to the stress of having her organs start to cook inside her body; I hope she turned out ok.
This is a prime example of how “leaving the windows cracked" is useless and just vaguely slows the heating process. This dog HAD NO WINDOWS AT ALL, NOT EVEN A ROOF and she was overheating in the open sun. Imagine how fast a metal container (your motor vehicle) will heat up in the direct sunlight. Once it reaches peak temperature, that same metal container serves to insulate the heat surrounding the unfortunate pet. People just do not realize this. It is a vicious cycle of increasing heat storage and WILL OCCUR even if the outside temperature is 70 degrees. A dog's ONLY WAY TO RELEASE HEAT -thermoregulate- is to pant. Not the most efficient thing, but that is the way it is. Dogs are not anatomically designed to be inside motor vehicles.
Symptoms of heat stress are heavy panting, red gums, and nervousness/anxiety. This can progress to heat stroke where the pet can actually lose consciousness, have seizures, lapse in to a coma, and die. During this process, damage is being done to all the internal organs because they are literally cooking at such elevated temperatures. This damage can later show up as organ failure, especially if the pet is older and repeatedly exposed to excessively high temperatures that the owner does not recognize.
I understand that a law was recently passed in Florida that protects citizens against civil or criminal charges brought against them for breaking into a car to rescue a pet, as long as the police are simultaneously notified.
If you find yourself with this situation-- do NOT immerse the pet in ice water! This can cause blood vessels to shut down and actually slow heat release and make things worse. ANY water that is tepid or cooler is going to cool the pet. If a pet is showing the symptoms described above, it indicates that their core body temperature is already above 103 degrees. Using 90-degree water will cool the overheated pet!
Get them out of the sun and in to a cooler place
Wet them down and call a vet
Place a fan to blow on them to help evaporate the water and remove the heat quickly.
Do not give a lot of water, but yes let them drink small amounts of tepid water that is not too cold to shock their body; let them sip until they are satiated.
Place cold towels in their armpits, neck, and against their inner thighs.
Wet their paw pads with cool water
In summary, learn to recognize signs of distress and don’t risk exposing your pets to these situations. Opening a window, or “leaving the top down” in the hot sun are not safe precautions in warm climates. Do not leave your pet in a vehicle for any reason when it’s hot out. If you must visit places that do not allow pets to enter, you’ll need to visit them at another time when you don’t have your pet with you. Educate yourself about what works best in emergency situations and pass it on so that others may learn and protect their own pets!