Everyone knows someone who has lost a pet under anesthesia. Most of the time there’s a reasonable explanation: underlying cardiac disease, organ failure, blood loss, and, most commonly, human error that allows for reversible signs of normal anesthetic effects to go undetected.
After these, we enter the realm of the aberrations, what we refer to as true adverse anesthetic reactions. These reactions have no explanation. Because they’re almost impossible to prove (process of elimination is the only method, usually not possible after the fact), we refer to all adverse reactions under anesthesia with the blanket term, AAE (adverse anesthetic event).
In the US, AAEs occur at a rate of 4 in every 1,000 cases. They do not always result in death, as the effects of the anesthesia can sometimes be reversed.
I have only had one AAE in my career—about a year ago. Inexplicably, a six-month-old kitten recovering from a spay (and showing normal signs of anesthetic recovery) suffered a cardiac arrest. After CPR and six days in the hospital the kitten went home—blind. She will likely never recover her sight.
Otherwise, my eleven years as a vet have remained remarkably reaction-free. Statistically, it’s just a matter of time before I encounter another AAE. For this reason, with each pet I anesthetize, I remind myself to remain as vigilant as possible to the signs of impending disaster.
Over the years, I’ve aborted a fair number of anesthetic procedures after the patient seemed `not quite right` while anesthetized. I’ve also been known to operate with extreme speed when a dog or cat suffered a negative change under anesthesia after the procedure was already well underway.
Get out. Get out. This is my mantra when the anesthephobia hits me.
Every vet knows the feeling: Everything’s going well until something goes wrong: a change in heart rate, a drop in blood pressure, erratic respiration, funky EKG patterns, major body temperature fluctuations, etc.
Panic is not the predominant feeling—though we might be forgiven this momentary sensation. It’s more like: Oh s---! Then you just get moving and give your drugs (if appropriate), complete or abort the procedure, and think twice about anesthetizing that patient ever again. Depending on the pet’s reaction, you might well order additional lab work, X-rays, and/or a cardiac workup.
With many AAEs, everything comes back clean—there’s no clear reason for a pet’s negative reaction. This only makes the fear more intense: there’s nothing, beyond our current precautions, that will prevent some of these reactions. Ultimately, some reactions are currently beyond our control.
The good news, however, is that human error is a factor. So is technology. Well-managed veterinary hospitals (with more experienced personnel, state-of-the-art equipment, and high tech anesthetic protocols) experience far fewer anesthetic deaths. Therefore, since the four-per-thousand statistic is the mean, most practices (I’m pleased to say, like mine) experience fewer. And deaths are even more rare. Our rate is more like 3 in 11,000. I did the math: One out of these three died. The other two lost their vision.
While AAEs are sad, indeed, I still believe in providing frequent dental cleanings and other routine procedures that require anesthesia. My own dog will never forego an anesthetic procedure that will improve her overall health. With careful monitoring and enough anesthephobia on the part of veterinarians and their staffs, AAEs can be favorably managed.
A healthy fear of anesthesia is a good thing.