Blood Pressure in Cats

Blood pressure in cats

What is blood pressure?

We all know that blood is pumped around the body by the heart. Blood pressure is the pressure exerted by the blood on the walls of the arteries.

There are two readings from blood pressure tests:

Systolic – Is the pressure as the heart contracts

Diastolic – Is the pressure as the heart relaxes and fills with blood

What is the normal blood pressure in cats?

Systolic – 110 to 160mm/Hg (millimetres of mercury)

Diastolic – 55 to 100mm/Hg

Low blood pressure in cats is:

Systolic – 90 – 100mm/Hg or lower

Diastolic – 50mm/Hg or lower

High blood pressure in cats is:

Systolic – 160mm/Hg or greater

Diastolic – 100 – 110mm/Hg

How is blood pressure measured in cats:

As with humans, an inflatable cuff is placed on the cat’s front leg or tail. In humans, a stethoscope is also used, this isn’t possible in cats and a Doppler or oscillometric device is used instead.

High blood pressure in cats:

High blood pressure (hypertension) is a common disorder most commonly affecting middle-aged to senior cats. It is usually caused by kidney problems, Cushing’s disease or hyperthyroidism. Symptoms may vary depending on the underlying cause. High blood pressure damages the blood vessels, leading to damage to organs, especially the eyes, heart, brain, and kidneys.

Symptoms of high blood pressure include:

  • Visual impairment, including fixed and dilated pupils, retinal haemorrhage, retinal detachment or blindness.

  • Enlargement of the heart leading to congestive heart failure and accompanying symptoms such as lethargy, breathlessness.

  • Neurological symptoms such as ataxia (wobbly gait) and seizures.

Finding the underlying cause (if there is one) and treating that is necessary to bring high blood pressure under control. Other treatments may include controlling dietary sodium, administration of vasodilators, beta-blocking drugs and diuretics.

Low blood pressure in cats:

Known as hypotension, low blood pressure may be caused by the following conditions:

  • Shock

  • Trauma – Internal or external bleeding

  • Certain heart conditions

  • Certain medications such as anesthesia

Symptoms of low blood pressure include

  • Dizziness and confusion

  • Loss of consciousness

  • Pale gums

  • Rapid breathing

  • Irregular heartbeat

The most common cause of hypotension is low blood volume. This may occur as a result of heavy/prolonged bleeding, excessive fluid loss from vomiting or diarrhea, or dehydration.

Treatment is aimed at addressing the underlying cause.