Case studies will be utilized to highlight major points in this presentation.
Why should I measure blood pressure?
Many of the diseases seen in everyday practice can cause high blood pressure
Hyperthyroidism
Diabetes mellitus
Renal, hepatic, and cardiac insufficiency
Hyperadrenocorticism
Obesity
Neoplasia – pheochromocytoma; mineralocorticoid-secreting tumor (primary hyperaldosteronism) Uncommon in cats.
Some of the drugs/nutraceuticals used can cause high blood pressure:
Drugs – phenylpropanolamine (PPA), phenylephrine, theophylline, aminophylline
Supplements/ Nutraceuticals – 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)
Hyphema (blood in the eye)
Dilated pupils
Increased tortuosity of retinal vessels
Decreased/ increased appetite
Vomiting
Increased water consumption
Increased urination
Weight loss
Lethargy
Heart murmur
Seizures
Collapse/ Syncope
Abnormal behavior
Proteinuria
Epistaxis (nasal bleeding)
Hematuria (blood in the urine)
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 prolonged procedures performed under anesthesia
Indirect measurement
Doppler ultrasonic method preferred method for cats
Oscillometric method –automatic, useful during anesthesia, use upper forelimb for best results.
Technique tips
Animal positioning
Minimal restraint
Minimal stress
Sitting
Lateral recumbency
May be performed in the exam room with the client or in a separate area.
At the level of the heart.
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".