Summertime Trauma: The Hit-By-Car (HBC) Dog

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As an emergency critical care veterinary specialist, I spend most of my time working in the ICU and ER. Unfortunately, in the ER, I see a huge spike in trauma to dogs and cats during the summer…particularly on days with nice, sunny warm weather. (As an FYI, NFL football Sundays and full moons seem to be particularly busy shifts in the ER, too!)

Some examples of common summertime trauma?

  • The hit-by-car (HBC) dog or cat
  • "Big-dog-little-dog” (BDLD) attacks
  • Cats attacked by predators (e.g., dogs, coyotes, mountain lions, neighborhood kids)

The good news? Thankfully, with the improvement in quality of veterinary medicine, many of these trauma cases survive. These cases can be rewarding to treat as an emergency doctor, as you physically are saving a life.

That said, I’d rather not see trauma cases in the first place. That’s because they can be life-threatening and cause significant pain and injury to your dog or cat. Also, trauma cases can be very expensive for you to treat, as they often require emergency stabilization, oxygen therapy, pain medication, blood transfusions, diagnostics (like blood work, x-rays), minor or major emergency surgery under general anesthesia, heart and blood pressure monitoring, and life-saving 24/7 care. This can add up into the thousands of dollars.

When it comes to being a HBC, the severity of trauma from range tremendously, from mild scrapes and bumps to death (these often never make it to the ER, due to severe, acute internal bleeding). Common consequences of HBC in dogs and cats include the following medical problems:

  • Pneumothorax (e.g., a tear in the lung lining, resulting in abnormal leaking of air out of the lung into the chest cavity)
  • Fractures (e.g., typically of the limbs, requiring expensive surgery to repair)
  • Pulmonary contusions (e.g., lung bruises, which result in difficulty breathing or coughing of blood)
  • Road rash (e.g., having the skin shredded off thanks to the drag against asphalt)
  • Degloving wounds (e.g., having the skin ripped completely off the bone or body, resulting in expensive surgery and daily bandage changes which often require sedation for placement)
  • Head trauma 
  • Eye proptosis (e.g., having your pet’s eyeball “pop” out from severe facial fractures or trauma)
  • Internal bleeding (e.g., laceration of the spleen or liver)

Bladder rupture (e.g., tearing of the bladder or ureters – the tubes leading from the kidneys to the bladder, resulting in severe pain and an expensive surgery to repair the rupture) Bile peritonitis (e.g., rupture of the gall bladder, resulting in leaking of bile into the sterile abdomen)

This list of complications from HBC isn’t all-inclusive, but gives you a good idea of the severity of trauma that can happen to your pet when hit by a car.

So how do you prevent HBC? By avoiding the most common reasons why I see pets getting off-leash or escaping from their safe home environment, like the following:

  • Dogs or cats escaping from the yard (e.g., someone left the gate open)
  • Dogs or cats escaping inadvertently out of the house by an open door (e.g., someone was opening the door to let the pizza delivery guy in)
  • Pet owners letting their dogs run off leash when their pet isn’t under strict voice command
  • Dogs hopping over their fence or digging out from underneath
  • Pet owners using a long retractable-type leashes, only to have their dog hit on the edge of the road (as the pet owner can’t reel them back on the leash in time)
  • Dogs chasing cars (please, teach your dog that this is bad!), and lastly, 
  • Pet owners accidentally running over their own dog in the driveway (This type is actually one of the worst types of HBC, as it’s a “slow roll” and results in more internal damage).

By being aware of these preventable causes, hopefully you can help minimize the risk of your pet being HBC.

If you have any questions or concerns, you should always visit or call your veterinarian – they are your best resource to ensure the health and well-being of your pets.