Heatstroke in dogs: a potential killer that's easy to avoid
Felix Paige
"Every summer, dogs in Hong Kong die from preventable heatstroke, often with owners who really should know better. Pet owners, please take note: it does not take long for a walk in the sun to turn to disaster. I have seen dogs die from heatstroke after only out walking for less than an hour."
Heatstroke, the vet says, is a situation where the body temperature remains above normal for an extended period of time - and the higher the temperature, the faster the damage to vital organs and the less reversible the damage.
Kenda explains that there are two main ways to release heat from the body - conduction and evaporation. Conduction is obstructed when the dog has a thick coat. Heat loss from a dog's body is mostly by evaporation. "However, unlike us, dogs do not have sweat glands over their body, only in their paws, and these are not used for heat loss. The most effective way for a dog to lose heat is by panting."
The dog's tongue hangs out and is very pink as the blood vessels dilate to enable the blood to be cooled by the evaporative process, and the dog will breathe rapidly to exchange the air as fast as possible. "Remember that this evaporative cooling implies that moisture is lost from the dog's body. This moisture needs to be replaced by drinking. Otherwise, the dog will rapidly dehydrate."
Generally, evaporative cooling by panting is a good technique to release heat, the vet says. But in a Hong Kong summer this method is not as efficient. "Unfortunately, the effectiveness of evaporative heat loss diminishes when the humidity is 70 per cent or more, which is almost every day here during summer."
The good news is that there are some preventative measures that can be taken to protect a dog from heatstroke in the coming months.
First, Kenda says, be sensible when considering taking a dog for a long walk. "Think how comfortable you would be going for a walk in a light fur coat."
The vet's advice is to make sure to take plenty of water for the dog to compensate for the moisture lost through evaporative cooling. "There are collapsible drinking bowls that are easy to carry."
Additionally, try not to walk directly in the sun, but choose a shady path. "Stop often to let the dog pant, drink, rest its muscles and fully immerse in water if possible. Remember that heatstroke does not just occur on a walk. Never leave your dog in a parked car during the summer months, and never leave a dog on a small balcony in the sun. And always ensure that your dog has plenty of fresh water to drink."
If a dog does begin to show signs of heatstroke such as weakness, or it collapses, there are immediate measures that can be taken by owners, Kenda says.
"Immediately take the dog away from the heat source into a shady area and immerse the dog into cool water if available, or pour water over it. Most importantly, get to a vet as soon as possible. This is important, as every minute counts."
Once at the veterinary clinic, the dog will be placed in a cool water bath and covered with ice packs, and intravenous fluids will be administered to help overcome the shock and to rehydrate the dog. The aim is to get the temperature down as soon as possible and to try to stop damage to the vital organs, Kenda says.
Prevention of heatstroke is much better than trying to save a dog that has fallen victim to heatstroke. "Think before you take your dog on a walk - don't let your dog be a hyperthermia victim this summer."
