You may be familiar with the idea of having your own blood pressure checked regularly, but did you know this is also advisable for pets?
Just like people, dogs and cats suffer from high blood pressure or hypertension — only for a furry friend, it is more likely to arise because of an underlying health complaint rather than a stressful commute to work!
It is thought that around 65% of cats with kidney disease also have hypertension, whereas for cats with overactive thyroid glands the figure is a staggering 87%. And just in case you thought we were leaving our canine companions out of the crush, dogs who have Cushing’s disease but are otherwise healthy have an 80% risk of hypertension.
A common and distressing symptom, especially in cats, is sudden blindness. This is caused by fluid building up behind the retina which forces it to detach. If caught early, prompt treatment may save that pet’s sight.
In dogs, the symptoms can be even more dramatic, including “funny turns” or, more seriously, strokes. Sadly, the first sign can be something as awful as sudden death — hence the need for regular blood pressure screening to catch the problem before a catastrophic event happens.
Blood pressure is governed by a complex interplay between how hard the heart pumps and the resistance to blood flow in the circulation. Several factors influence this, including the presence of hormones triggered when blood flow to the kidney falls.
Changes in the blood vessels make pushing blood around the body more difficult, increasing resistance to flow, which in turn increases blood pressure. This is why certain conditions are associated with hypertension, although a fair few cases are “idiopathic,” which means no cause is found.
The clinician may get a clue that your pet has hypertension from her eyes.
A common sign is fluid building up at the back of the eye between the retina and the globe. Retinal edema is a classic sign and can quickly lead to retina detachment and blindness.
To confirm the diagnosis, the vet tech will measure your pet’s blood pressure. This is a painless procedure, much like having your pressure checked at the doctor’s office.
The only difference is that the pet will need a small amount of fur clipped just above her paw to allow the sensor to make contact with the skin. A cuff is placed around the pet’s arm and inflated. The technician notes the pressure within the cuff that stops the arterial pulse.
This video features a veterinarian and vet tech demonstrating the procedure of taking blood pressure from a dog:
The first thing is to address any underlying health issues. By treating the root cause, the hypertension may resolve. Thus, cats with kidney disease should go onto special renal diets, and, happily, the medication commonly prescribed for these cats, benazepril, also has a secondary effect to reduce blood pressure.
If blood pressure remains high, then most patients are started on a human medication called amlodipine, which is very effective at reducing blood pressure. Regular monitoring is essential until and after blood pressure stabilizes to ensure control is maintained.
Regular screening of pets, especially those classed as “senior,” can detect blood pressure changes in the early stages before they cause a problem.
Current recommendations are that all dogs with Cushing’s disease should have their blood pressure measured every 3 months, which also goes for cats with kidney disease and/or hyperthyroidism.
If your pet is over the age of 7 years but is otherwise well, then once-yearly screening is fine. Once he reaches his teens, it should be twice a year.
- The 5-Minute Veterinary Consult. Tilley & Smith. Publisher: Williams & Wilkins. 706–707.
This pet health content was written by a veterinarian, Dr. Pippa Elliott, BVMS, MRCVS. It was last reviewed Nov. 25, 2014.