Feline blood pressure measurement: You can do it! (Proceedings)


Feline blood pressure measurement: You can do it! (Proceedings)

Apr 01, 2010

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

           Diabetes mellitus
           Renal, hepatic, and cardiac insufficiency
           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
           Increased water consumption
           Increased urination
           Weight loss
           Heart murmur
           Collapse/ Syncope
           Abnormal behavior
           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
           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".