Don’t leave animals in a hot car. It could be the last road trip they ever take.

Summer has just begun but many parts of the country have already experienced record heat.

Every year around this time my heart breaks as I read about companion animals dying from heatstroke in parked cars.

It’s estimated that hundreds of cats and dogs die each year from being left in hot cars, while even more become seriously ill. While it's easy to think that only animals who belong to bad people die in hot cars, it's simply not true. It can happen to even the most devoted animal lover.

“I was just gone a few minutes,” “It wasn’t even that hot,” “I cracked open a window.” These are the common responses of grieving family members, when they return to their cars to find their beloved cats or dogs have died of heatstroke.

It’s all too easy, when one is tired, distracted, or stressed, to misjudge the length of time a companion animal has been locked in a hot car or to forget the animal is there at all. As the climate changes, and it becomes warmer for longer periods each year, there’s more opportunity for cats and dogs to suffer from heat exhaustion or heatstroke in cars, even on fall and spring days.

The thing to remember is that while outside temperatures may not be hot for you, they can be lethal for your cat or dog trapped inside a car. A moderately warm temperature outside a car can make it feel like an oven inside. Temperatures in vehicles can rise 20 degrees Fahrenheit in just 10 minutes, going from 70 degrees to a scorching 90 degrees. The longer an animal is trapped inside, the hotter it gets. Even on hot, partially cloudy days, temperatures in parked cars can exceed 125 degrees in about 20 minutes. Animals can die of heatstroke in cars even when outdoor temperatures are as low as 60 degrees.

How many of us park in the shade and roll down our car windows on hot summer days, so our cat or dog can stay cool inside? What we don't realize is that, even with the windows open, a car interior can feel like a roasting pan in minutes. A 2005 study on heat stress in cars, published in the journal, Pediatrics, found cracking open a window does not slow the heating process.

Heatstroke or hyperthermia, as it is medically known, is a life-threatening condition that leads to organ dysfunction in the liver, kidneys, heart, lungs, and brain. It's caused when humidity and high heat elevate your companion animal's body temperature to a point where they can no longer cool themselves. Without immediate intervention, the animal's organs can shut down, leading to a coma or death.

What are the signs of heatstroke? Rapid panting, drooling, anxiety, nosebleeds, muscle tremors, vomiting, diarrhea, lethargy, and collapse can all be signs that a dog or cat is suffering from heatstroke.

The good news is more and more legislators are recognizing the life and death consequences of people leaving their companion animals in hot cars. About half of all states now have some kind of “hot car law” on the books, though these laws vary.

What can you do if you see a cat or dog in a parked car by himself? In several states, Good Samaritan hot car laws allow private citizens to break into vehicles and remove companion animals to save their lives. California, Florida, Massachusetts, Ohio, Tennessee, and Wisconsin all have hot car laws that protect Good Samaritans. Arizona, Colorado, and Indiana passed similar laws this legislative session and in Alabama and Nebraska the laws are pending.

Still the laws aren’t perfect. Even in states with hot car laws, it can be illegal for Good Samaritans to break into vehicles to remove suffering animals, without first having called 911. Some states require a Good Samaritan to wait with the rescued animal by the damaged car until law enforcement arrives. Other states only allow law enforcement officers or humane officials to remove a distressed dog or cat. Under such laws, there's a danger the animal could die before law enforcement arrives.

Then there are states like New Jersey and West Virginia where leaving animals in hot vehicles has been added to the states’ animal cruelty provisions, though without immunity provisions for rescuers.

But there is room for optimism. Hot car laws are becoming increasingly popular. If your state doesn't have one now, it may have one in the near future. Even if you live in a state without a hot car law, it doesn't mean you can't rescue a companion animal. It means that you must weigh the consequences of doing so. For many, saving a dog's or cat's life is worth the risk of arrest and civil fines. Penalties for people who break into cars to rescue animals are often limited, especially when the Good Samaritan shows they took reasonable steps to obtain help before entering the car. Plus, state prosecutors are often wary of the negative publicity they could incur by charging someone for saving a companion animal's life.

In Georgia, for instance, an army veteran was arrested for smashing a car window to save a dog in distress. The charges were dropped and the owner, who pressed them, was cited for animal cruelty. This is just one example of prosecutors being motivated to charge animal owners under animal-cruelty legislation for leaving animals in hot cars and to dismiss charges against Good Samaritans.

But what about those of us who find it difficult to refuse our dog or cat a trip in the car? We need to be mindful that if it's hot for us, it can be even hotter for them. And we need to remember that, while you might feel sad for Spike or Ginger to be left at home, it can be deadly when they are left in a hot parked car.

If you love your companion animal, don't leave them in a hot car. Their lives depend on it.

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