There are some growing trends that are making the use of intravenous propofol less necessary during animal euthanasia.  In companion animal medicine, it’s very common for veterinary staff to administer propofol (often expired) before the injection of the euthanasia solution pentobarbital, with the goal of inducing anesthesia in patients before they succumb to the effects of pentobarbital.  This according to the Companion Animal Euthanasia Training Academy (CAETA), is always a good thing, however as euthanasia evolves to include more pre-euthanasia drugs without intravenous access, the question centers on whether propofol is still necessary, and is its continued use slowing down a more modern approach to the procedure?

Propofol’s popularity during companion animal euthanasia* goes back decades, although just how far back is unknown.  It gained fame as a means to reduce active signs of death (ex. agonal breathing) during euthanasia, yet research shows it actually does very little (1). At this point, its administration just before pentobarbital seems more out of habit for practitioners than anything else. Even with little known benefit, many could ask what’s the harm?  It’s not hurting anything so why stop?  From my perspective, the continued reliance on propofol is slowing the important shift towards a gentler euthanasia experience, namely the use of pre-euthanasia sedatives to induce sleep before the technical aspect of euthanasia begins.

The good death revolution places emphasis on the patient experience. Companion animal euthanasia, as defined by pet owners (and soon to be veterinary professionals through an upcoming study), exemplifies a pain-free, anxiety-free procedure (2). Anxiety-free may be what’s lacking the most with propofol use today.  In order to administer propofol, the veterinary team must first place an indwelling intravenous (IV) catheter.  This is typically done with the patient awake and aware of the restraint, plus is often done in the absence of the pet owner.  IV catheters are usually placed ‘back’ in the hospital’s treatment area while the owner remains in the exam room waiting for their pet to return.  

So what’s the alternative? My recommendation is to provide a subcutaneous or intramuscular injection of a sedative to induce deep sleep before placing an IV catheter to administer the euthanasia solution.  It’s about giving sleep-inducing drugs in the least painful and stressful way, which usually means less restraint for the pet while sitting right next to their beloved owners.  There is no need to separate the pet from the owner during this already delicate and emotional time, and the 2022 study showed pet owners want the option to always be with their pet. This paradigm shift may seem unnerving to veterinary teams at first, but if they follow the lead of their colleagues performing home euthanasia, who already do this as the standard of care, they will soon see how reliable and smooth this pre-euthanasia sedative approach can be.  

How Veterinary Teams Can Make the Switch to Pre-euthanasia Sedatives Instead of Propofol
1. Take a team meeting to discuss the change
2. Determine which IM or SC sedation/anesthesia protocols to use with various species
3. Standardize keeping the pet in the room with the owner; no forced separation
4. Learn about intraorgan euthanasia injection techniques to reduce the need for intravenous access
5. Leverage pentobarbital as an anesthetic instead of propofol

Propofol will continue to be useful for surgical induction in veterinary hospitals, and for short procedures with a quick recovery. For euthanasia, it feels like it’s run its course. Let’s aim higher to reduce patient stress during the final moments of life. If an IV catheter is already placed, sure propofol is useful. If not, it’s time to give sleep-inducing drugs in a gentler fashion.

* Propofol before euthanasia is most commonly used in veterinary hospitals, zoos, and some research settings. It is rarely used in animal shelters or other animal industries where euthanasia may be required.

References

1. Bullock JM, Lanaux TM, Shmalberg JW. Comparison of pentobarbital-phenytoin alone vs propofol prior to pentobarbital-phenytoin for euthanasia in 436 client-owned dogs. J Vet Emerg Crit Care 2019;29(2):161-165.

2. Cooney K, Kogan L. How Pet Owners Define a Good Death. 2022. https://www.dvm360.com/view/how-pet-owners-define-a-good-death-