Testing Blood Pressure Using an Automatic Device
How to measure a dog’s blood pressure at home
A health exam for all adults includes a blood-pressure reading. So why not for our dogs? There are a few reasons that veterinarians save blood-pressure testing for only certain cases.
The first is money. Because vets constantly face clients who are unable or unwilling to pay for anything “unnecessary,” veterinary clinics are forced to offer a la carte services. The basic office-visit fee includes the veterinarian’s brief examination and writing applicable prescriptions. Anything else is an additional charge; veterinarians say this helps the client determine the cost of veterinary care.
“Veterinary exams would have to climb more than $100 per visit to include ancillary services that are ‘included’ in physician visits,” says Eve Ryan, DVM, of Baldwinsville, New York. “As unfortunate as it may be, many pet owners do not want or cannot afford all of the high-quality medical services that are recommended, so non-exam services are separated out.”
Another reason that veterinarians are hesitant to perform regular blood-pressure checks is because of the high incidence of false positives. “You don’t want to risk inappropriate treatment due to an invalid diagnosis,” says Bruce Kornreich, DVM, PhD, DACVIM, a cardiologist at the College of Veterinary Medicine at Cornell. “We don’t want to over-treat.”
Although an estimated 20 percent of humans suffer from “white-coat syndrome” (temporary high blood pressure caused by the anxiety associated with visiting the doctor), dogs aren’t as easy to sort out. “It’s reasonable to assume that dogs also suffer from white-coat syndrome,” Dr. Kornreich says, “but validation is different.” In human medicine, the patient sits quietly for a few minutes while the nurse prepares to take blood pressure. She might chat about the weather or an upcoming holiday to distract the patient’s thoughts, hopefully normalizing any white-coat effects. The blood-pressure reading itself is quick.
Visualize your dog in the veterinarian’s office, with the many smells, noises, and distractions. Just getting the dog to stand on a weight scale can throw him into a hyper state. Now add one or two staff members to restrain the dog and a Doppler ultrasound beep as the reading is done.
“It’s difficult to get blood pressures if the dog won’t stay still,” says Eileen Fatcheric, DVM, of Syracuse, New York. “The readings can be falsely elevated in a clinic setting, especially if the dog is anxious, and it is time-consuming.” Veterinarians are advised to take at least three readings – and preferably five to seven! – once the animal is quiet. The first reading is always disregarded.
Of course, the standard back-up plan physicians use is asking human patients to monitor blood pressure at home and report back to them. Over-the-counter human blood-pressure monitors are relatively inexpensive and foolproof. Get a cuff the right size for the patient and you’re good to go. Not so with dogs.
There are three main methods of measuring blood pressure in dogs. The gold standard is direct arterial monitoring, which is invasive (involving a catheter) and usually done only under anesthesia.
The Doppler ultrasound method is used in many clinics, but it, too, is not without drawbacks. “It involves a messy gel that is necessary for the probe to detect the pulse sounds, and operator error is a possibility,” Dr. Ryan says. “In my experience, the noise associated with the Doppler unit often frightens the animal unnecessarily. Headphones are available, but this mode is becoming outdated. New oscillometric devices used in modern veterinary medicine are well-calibrated, easy to use, reliable, and mess-free.”
Indeed, modern veterinary oscillometric devices – similar to human at-home blood-pressure measuring machines – have undergone dramatic improvement, and more veterinary clinics are utilizing them. But that doesn’t mean you can expect to buy a device at Walmart and take your dog’s blood pressure at home.
“Machines made for humans might give a ‘ballpark’ reading on a dog, but it wouldn’t be expected to be accurate, nor should it be used to make any medical decisions regarding medication or treatment,” Dr. Ryan says. “Only an animal-calibrated machine used with the appropriately sized cuff, used on the appropriate parts of the patient’s anatomy, should be used for medical decisions. Choosing the appropriate size cuff and its placement requires an understanding of the anatomy of the patient, which may change, depending on species and breed.”