First off, thank you for being so proactive with Phoebe. It’s the best place to be! Your question really got me thinking. Because I have no patients who are getting their blood pressure measured at home! So I asked myself, why is that? Am I doing something because it's just the way it was taught to me, and I’ve never questioned it? Is there a reason? I have a lot of pets who get their blood sugar measured at home. So why not blood pressure?
So I looked into it. Because why should it be any harder than obtaining a blood glucose measurement at home? Why don’t I do this?! So look into it I did. And OMG.
It’s Alice down the rabbit hole! I can see why you have reached a point where it is hard to know what to do next. So the requirements you have are very reasonable. Simple to operate. Not too costly. Just like most of the glucometer’s we use to measure blood sugar at home. So, why is it rarely done to my knowledge or recommended?
Let's break it down. We have two types of machines commonly used for pets in clinic. We have oscillometric devices such as the Cardell. You place a cuff on the forearm or base of the tail, press the button, and it inflates and deflates a cuff and as it makes it’s measurement.
We also have the ubiquitous brown box, know as the ultrasonic doppler, also known as the Parks doppler machine (http://www.parksmed.com/vet_prices.php). I’ve never been in a clinic that hasn't had one of these two present (provided the clinic was equipped to measure blood pressure - some don’t offer it).
Based on our requirements of ease of use, right off the bat the Cardell would win, but to figure out the cost of one you need to schedule a consultation. On their website there is an animated cartoon dog that asks that you “request pricing”. I'm just going to assume it’s the cost of a compact economy car. Like a Toyota Yaris or something like that. The Parks doppler comes in at a cool thousand once you get all your cuff’s and accessories lined up. I have trouble getting them to work sometimes...it's a black art. I have technicians who are better using it than I am. It takes daily practise.
The Park’s Doppler units are considered more accurate in cats and small dogs than the oscillometric ones. It gets worse, because vet’s debate all day about which type is better, and which methods get the most accurate results. There are conference proceedings and lectures dedicated to this one subject.
So where does this leave us, with the less expensive, simpler machines in the drug store? Here is the deal. It’s not impossible to use one. They are mostly oscillometric, which means they are simple to use, but perhaps less accurate in cats unless you really have the right cuff and have your technique down pat. If you can find one with a cuff that will fit a cat, presumable you can hook it up an obtain numbers. Look at this one I found on ebay for 35 bucks:
Looks awesome! Part of me is tempted to buy it just to see if it would work…and then I got further down the page, and it’s a human set of cuffs that come with it that are not sized correctly for a cat. At least as I can tell from the pictures. So much of getting correct blood pressure numbers stem from using the right cuff. And the text suggests it's more for people but they are marketing it for pets. But still, what if it actually worked?
I know of specialists in this area that say that the human blood pressure machines won't work for cats. The feline blood vessels are much smaller, so this is why a Doppler device with a pediatric cuff or vet designed oscillometric device’s are used. So we need specific technology to be accurate. As well, the simple auscultatory technique (where they pump up the cuff and listen with a stethescope) commonly used in people, does not work for small animals because the “frequency of the sound associated with blood flow to a limb is too low to be audible just with a standard stethoscope”.
So. Maybe out there, there exists some machine, just like the ebay one, that is the right tech, with the right sized cuff, and mass produced to be cheap. Just waiting to be found. It would be great if we could buy a hundred of all the different variants of these inexpensive machines, compare them to the standard machines in clinic, and figure out if any of them was a star! So far that list doesn't exist to my knowledge, but it would be great.
Thanks for your question,