The silent killer (Proceedings)


The silent killer (Proceedings)

Feline systemic hypertension
Apr 01, 2008

Why should I measure blood pressure?

Many of the diseases seen in everyday practice can cause high blood pressure:


Diabetes mellitus

Renal, hepatic, and cardiac insufficiency



Neoplasia – pheochromocytoma; mineralocorticoid-secreting tumor (primary hyperaldosteronism)

Some of the drugs/nutraceuticals used can cause high blood pressure:

Drugs – phenylpropanolamine (PPA), phenylephrine, theophylline, aminophylline

Supplements – Ma huang (Ephedra sinica)

Many of the clinical signs seen every day could be due to high blood pressure:

Acute blindness (due to retinal hemorrhage/detachment)


Dilated pupils

Increased tortuosity of retinal vessels

Decreased/ increased appetite


Increased water consumption

Increased urination

Weight loss


Heart murmur


Collapse/ Syncope

Abnormal behavior



High blood pressure can be a "silent killer"

No overt clinical signs may be noticed.

Can be the primary problem – "essential" hypertension – with no underlying cause.

The time to diagnose high blood pressure is before damage is done. Retinal hemorrhages and detachment can be avoided in a well-managed feline patient. I recommend that Doppler ultrasonic blood pressure measurements begin in all patients at an early age as part of their health care program. That helps the veterinarian establish a baseline for each individual cat. Senior cats, which have a greater risk of developing diseases that cause high blood pressure, should have their blood pressure checked every 6 months. Once a cat has been diagnosed with a disease that can cause high blood pressure (ex: Chronic kidney disease), blood pressure measurements should occur at least every 3 months or sooner if any concerns arise. Your clients are well educated about high blood pressure, so it is easy for them to understand the importance of blood pressure control in their cats.

How do I measure blood pressure?

Direct arterial measurement

Impractical for routine monitoring

Useful during procedures performed under anesthesia

Indirect measurement

Doppler ultrasonic method - preferred method for cats

Oscillometric method

Blood pressure measurement: Technique tips

Animal positioning

Minimal restraint

Minimal stress


Lateral recumbency

May be performed in the exam room with the client or in a separate area.

While we try to perform blood pressure measurements under these ideal situations, there are exceptions to the rule. Some cats are "difficult to handle", but still need to have their blood pressure measured. An accurate blood pressure measurement can be obtained, even on a cat that is trying to "eat you alive".