Post traumatic stress disorder, or PTSD, is not a fully recognized veterinary behavioral phenomenon but some believe it exists and is probably more common than we think.
I have taught veterinary students about PTSD for many years, my initiation into this ongoing phobia being a particular case I saw many years ago. The dog in question was shot by a Boston police officer who thought the dog was going to attack him while he was pursuing a suspect.
In fact, the dog was only charging along behind him, energized by the excitement and commotion.
The .38-caliber bullet entered through the dog’s head, just missing vital structures and traveled along the dog’s neck, finally coming to rest in the chest wall. The dog sank to the ground in a pool of blood and his distraught owner was quickly on the scene trying to revive him.
As it turns out, the dog was not dead but close to it and heading down a path of no return, but his owner quickly scooped him up and brought him to nearby Angell Memorial Animal Hospital where the ICU staff worked wonders, plugged the leak (so to speak) and brought the dog back to viable condition with fluid therapy.
The dog’s recovery was slow, but recover he did—but behaviorally he was never the same.
Change in Progress
Starting as relatively secure though sensitive, he evolved into an extremely anxious and hypervigilant dog. It was almost as if he expected something bad to happen again at any moment. He never took his eyes off his owner and insisted on being in his company at all times, perhaps for reasons of safety and security.
From the day of the shooting, the dog became extremely scared, panting and pacing when seeing police cars (there was one parked nearby at the time of the shooting), flashing lights (on top of vehicles of any type), and black people (the policeman happened to be African American). If he could run away from any of these cues, that was always his first response, but running away wasn’t always possible, such as when he was in a car with his owner.
Shortly after the shooting, the dog exhibited presumed nightmares and developed “nocturnal separation anxiety,” so much so that it became impossible for his owner to sleep at night. In fact, he and his son had to take turns staying awake with the dog if either was to get any rest.
This dog’s condition met all the translatable criteria of human PTSD though, of course, no one could actually ascertain the precise nature of his inner turmoil. It was undeniable that the dog had an extremely traumatic experience and it seemed clear that the effects of that trauma haunted him indefinitely.
Anxious symptoms lasting more than three months is one criterion for diagnosis of chronic PTSD. Also, the dog became hypervigilant, made every attempt to avoid the stimuli associated with the trauma, had difficulty falling asleep, and nightmares or other terrifying experiences at night – also signs of PTSD.
Many years later, and after many lectures featuring this dog’s story as well as other post-traumatic personality changes in dogs, I was consulted by the national media about Gina, a dog of the Iraq war, who went to war well trained, chipper and psychologically healthy, only to return a psychological shadow of her former self. The press could not believe the handler’s diagnosis of PTSD—in a dog?
The dog had been used to flush insurgents from houses in Iraq, after Marines had thrown in a “flash bang” grenade to pave the way for their safe(r) entrance. This dog experienced entering houses as being associated with loud bangs and flashing lights and pure bedlam. A traumatic experience? I would think so, especially for a dog who did not really understand what was going on.
When Gina returned to the U.S. from her tour of duty, she was constantly anxious and on the lookout for trouble (hypervigilant), would not enter houses as part of her routine training as she had before (avoidance) and had other anxieties though she had shown nothing of this nature before.
She was a changed dog personality-wise and PTSD was the only reasonable explanation of what was ailing her.
The permanence of such negative learning is enabled by massive release of catecholamines in the brain in response to a near-death experience.
This was illustrated in rodent experiments in which premedication of rats with beta blockers prior to some dreadful experience—like exposure to a predator—prevented the extreme and long lasting effects of the experience.
But how useful is that information clinically? Not much if you don’t know when the trauma is going to occur.
As it turns out, however, more recent work has shown that beta blockers given within a few hours of a traumatic event also prevent this permanent negative learning, somehow preventing bad memories from being imprinted on memory centers, such as the hippocampus.
Indelible post traumatic learning can be thought of as adaptive when it occurs at a functional level. It is a survival advantage for an animal to remember where danger lies, to avoid that location or other animal, and to remain more watchful in the future.
The difference between functional and dysfunctional post traumatic learning is one of degree, the latter being an excessive and debilitating version of the former.
Why some dogs get it while under similar circumstances others do not is an enigma—but the same is true of soldiers, some of whom return time and time again to war without developing PTSD while others do not fare half as well.
The reason for the discrepancy may have to do with nature (genetics) protecting some against psychological trauma while others are more sensitive to such adverse conditioning.
For veterinarians who do not see many gunshot victims or dogs of war, there are other occasions much closer to home that may engender the same response. Take automobile accidents and ICU experiences, to name two. These are both known as potential PTSD triggers in people, especially if horrendous events are experienced in a conscious or semi-conscious state.
Being ventilated is one ICU factor that seems to be closely associated with PTSD. I am told the experience of being paralyzed and unable to breathe for one self is absolutely horrific, as is surgery on patients who are partly aware.
We should all handle these patients with metaphorical “kid gloves” to ensure they experience as little psychological trauma as possible, making best use of analgesics, hypnotics, sedatives, anamnestics (benzodiazepines) and local, regional and general anesthetics.
Also, it may not hurt to give an immediate post-traumatic beta blocker (circulatory events not withstanding)—just to hedge one’s bets. An ounce of prevention…