Be sure to have your pet get regular blood pressure checkup

The faces in the exam room were grave. Their doctor had just explained that dietary changes and potential exercise changes may be necessary. A long-term, probably lifetime medication would need to be started. The problem was a blood pressure reading well in excess of normal.  Meanwhile, the patient continued to chew on his treat and wag his tail, clueless to the concern of the humans in the room.

Most pet owners would admit a lack of knowledge or perhaps even a lack of concern about hypertension, or high blood pressure in pets. After all, since they don’t have the same vices as we do, they shouldn’t be at risk, right? Well, the answer may be a little more complex than just life style choices.

One study showed that 93 percent of dogs with chronic kidney disease also suffer from high blood pressure. Other studies cite that more than 60 percent of dogs over 8 years of age suffer from this often silent disease. The incidence in cats is probably even higher. One reason that so little is known about how many pets are actually affected is the fact that blood pressure measurements are not routine during many pets’ office visits. Considered to be one of five vital signs for humans, blood pressure in our pets has not received the same attention.

Blood pressure in humans is measured by gently occluding, or blocking, an artery in an arm or leg.  A stethoscope is then used to listen for the return of the pulse as the pressure is slowly released.  This point is known as the systolic blood pressure, or the higher of the two numbers you will hear or read.

Next, the pressure continues to be released and until the constriction causes no change in pulse sound. That pressure is called the diastolic pressure.

Blood pressure is then read as systolic over diastolic, or, for example, 120 over 80.

For dogs and cats, the stethoscope is not sensitive enough to hear the pulse sounds and it is virtually impossible to detect the diastolic signal. Most veterinarians will simply record a pet’s blood pressure as the systolic measurement. Many veterinarians who utilize blood pressure measurements use an ultrasonic probe to “hear” when the pulse returns to the artery. The probe will then convert that signal into an audible sound for the doctor.  Experts caution both veterinarians and owners to never become alarmed at a single high reading.  The results must be repeatable to be significant.

With high blood pressure, blood vessels can become thickened and stretched and may eventually rip and tear, causing bleeding. This may not be immediately noticeable, but as small vessels in the eye and in the kidneys begin to be destroyed, patients will begin to show clinical signs.  Symptoms of high blood pressure are often unnoticed by the owner. A sudden or gradual onset of blindness can be the only outward sign that your pet may have high blood pressure. High blood pressure can worsen existing kidney disease, can cause bleeding in the brain and will eventually affect every organ in the body.

Fortunately for our pets, high blood pressure often results from another disease process. Controlling the first disease will often reverse or help to control the high blood pressure.  As with humans, certain drugs are available to help relax and dilate blood vessels, reducing the pressure. Some veterinarians also recommend salt restricted diets for hypertensive pets.

Many practices are adding blood pressure screening to their routine wellness examinations for older pets. Together with a comprehensive physical examination and routine laboratory tests, a blood pressure measurement every six months is an important way to help “senior” pets live longer, happier lives. If your dog is over 7 or your cat is over 9, please ask your veterinarian about regular blood pressure measurements.

Dr. Watts is a companion animal general practitioner and owner of Clevengers Corner Veterinary Care. He can be reached through ClevengersCorner.com or by calling 428-1000. Some columns contain material contributed by the Veterinary News Network.