Hypotension in the dog

Anyone who has ever had a friend or relative who suffers from high blood pressure will probably be familiar with the term hypertension, which is the correct medical name for the problem. However, on the flip side, it is also possible for people-and dogs-to suffer from the opposite problem too, which is called hypotension, and refers to an abnormally low blood pressure.

Hypotension can lead to a range of different symptoms and problems in the dog, and can be caused by a variety of different things, and so, the available options for supportive care and correcting the problem can vary considerably. In this article, we will look at hypotension in the dog in more detail, including the symptoms, causes, and risk factors for the condition. Read on to learn more about hypotension or low blood pressure in the dog.

What is hypotension?

Hypotension means low blood pressure, and blood pressure is measured in terms of the force exerted by the blood pumping through the arteries, as the heart circulates the blood. Whilst the healthy range of blood pressure in the dog can vary quite a lot, blood pressure that is too low can cause a range of problems, such as weakness, lethargy and even fainting spells.

Hypotension is sometimes a chronic, ongoing condition, although it can also be caused by injuries and accidents, particularly those that lead to shock in the dog, as a short term issue. The blood pressure of very fit, active dogs is naturally slightly lower than those of the average dog, and this can, in some cases, be an indicator of peak fitness and physical condition, in which case it is a positive thing rather than a problem. However, if this is not the case, or the blood pressure is low enough to cause problems for the dog in question, it can be an issue, as low blood pressure may mean that oxygen doesn’t circulate throughout the body sufficiently, which can starve the vital organs of enough oxygen for healthy function.

What sort of dogs are at risk for hypotension?

As mentioned, some very fit, active dogs in the peak of good health may display lower than usual blood pressure, and this is not deemed to be a problem, but rather an indicator of their superlative fitness levels. This is often the case with working farm Border collies and Siberian huskies that work or exercise a lot, and so in those cases, it is not an issue.

However, very large dog breeds and dogs that are underweight are more likely to develop potentially problematically low blood pressure than other dogs, and it is also more likely to occur in older dogs than juveniles, although hypotension can potentially present in dogs of any age, breed, size or condition.

What causes hypotension in the dog?

It is not always possible to identify why any given dog is suffering with hypotension, however, there are some known issues that can raise the chances of it occurring, or lead to the condition presenting for the first time. Any accident or injury that leads to a significant loss of blood will lead to hypotension, as there is simply not enough blood left within the circulatory system to maintain a healthy blood pressure. Low oxygenation levels of the blood can do the same, as the oxygen within the blood also helps to maintain a healthy blood pressure.

A range of different chronic health problems may also cause or contribute to the condition too, including heart problems, problems with the liver or kidney, and anaemia, or a low red blood cell count. Severe shock, as may occur if your dog is injured or has a serious allergic reaction to something can also lead to low blood pressure, as can long-term neglect and malnutrition or dehydration.

What problems does hypotension in the dog lead to?

Hypotension causes the major organs of the dog, including the heart and brain, to fail to receive enough oxygen, which is what leads to the most common symptoms and effects of the condition. Dogs suffering from hypotension will usually be lethargic, rather sedentary and not that keen on exercising, and may be reluctant to move or really do very much of anything.

The mucous membranes of the dog will usually be pale, due to the anaemia that hypotension can accompany, and affected dogs will be prone to dizzy spells and even, possibly, loss of coordination, which can lead to staggering around and disorientation, and potentially, fainting.

What can be done about it?

If you suspect that your dog may be suffering from hypotension, your vet can find this out quickly and easily by means of taking their blood pressure, and what the average norm for the blood pressure of any given dog is will vary considerably depending on their breed and size. If your vet does identify hypotension, they will then run a range of tests to determine what is causing it, unless it is obviously caused by an accident or incident that has led to loss of blood or shock, in which case, the hypotension will usually correct itself once the underlying problem has been resolved.

Generally, treatment of the underlying cause of the condition is the usual method of resolving hypotension in the dog, and it is unusual for your vet to provide medication or treatment for hypotension as a standalone issue.