Thrombus (blood clots) and their risks for dogs

One of the main processes of a healthy blood and circulatory system is the ability of the blood to coagulate and clot, which is of course vital for wound healing and the normal recovery from scrapes, cuts and other damage to both the skin and internal systems. However, blood clots that form in the wrong place or for the wrong reason can pose a serious risk to your dog’s health, because a clot can effectively stop up the body’s circulatory system and/or travel into major organs and lead to risks such as stroke and other acute and life-threatening conditions.

Dangerous blood clots can form within the body for a wide variety of reasons, and generally, the various risk factors for a potential clot can be identified and mitigated-such as if your dog has had surgery and will be sedentary or resting in one place for a long period of time.

A blood clot is known by the scientific name of “thrombus,” and knowing some of the risk factors and how clots are apt to form in the first place can help you to ensure that you do what you can to prevent them from developing-and help you to identify a potential problem in the making soon enough to intervene.

In this article, we will look at blood clots and their risks for dogs in more detail, including how they might form, how to identify a problem, and what can be done to treat them. Read on to learn more.

How might dogs develop a thrombus?

As mentioned, blood clotting is an important element of the normal, healthy circulatory system of the dog, but when a thrombus develops inappropriately or otherwise leads to a blockage or the circulation of the clot itself, it can pose a serious problem.

There are a huge number of different things can can potentially cause a thrombus, including sitting or lying still in one position for a long time-which is why airlines sometimes offer compression hosiery for people on long-distance flights, and encourage people to move around regularly.

Some of the potential causes of thrombus in dogs include:

• Recovery from surgery when the dog is apt to lie still in one position for a long period of time.
• Any other enforced or voluntary period of lying or sitting still in one position without moving around.
• Autoimmune disorders that can increase the viscosity of the blood, and make it thicker and more prone to clotting.
• Some forms of hypothyroidism make the blood more prone to clotting.
• Any condition that affects the bone marrow or the blood, such as leukaemia.
• Circulatory disorders that may lead to pooling of the blood in some areas of the body. This also increases the risk of thrombus formation in sedentary dogs.
• Narrowing of the veins and arteries to the heart, which can lead to blockages and clots.
• Anaemia.

These examples are just representative of some of the potential elements that can combine to increase the risk of thrombus or contribute to its development, and is by no means exhaustive. If your dog has a health condition or other risk factors for thrombus (such as after surgery) your vet should make you aware of this, and advise you of potential warning signs of problems.

What are the symptoms of thrombus in dogs?

The symptoms of a thrombus in dogs will often be invisible or very hard to detect until they become acute and problematic, and because a thrombus can develop in so many different areas of the body, the symptoms that they may present with in the early stages can be highly variable.

Thrombus in the extremities, such as the limbs and tail, may result in coldness in the affected area and potential paralysis, or the area in question may feel strange to your dog (such as by means of a pins and needles type sensation) which may cause them to try to shake it and manipulate it to restore circulation. This can potentially dislodge the clot and cause it to migrate to another area of the body, which can be very serious.

A clot in the area of the dog’s heart or lungs can lead to a range of systemic symptoms such as shortness of breath, lack of tolerance for exercise and other obvious acute indications of a problem, and most notably, it may well be very hard to find the dog’s pulse.

Ultimately there is no set of specific symptoms for a thrombus in any given dog or part of the body, and identifying a thrombus quickly largely depends on being aware of the risk factors for thrombus and the symptoms that it can cause combined.

Again, your vet should appraise you of the relevant risk factors for your own dog and the specific symptoms to be alert for, if relevant.

Can a thrombus be treated?

A thrombus is a potentially life-threatening condition in your dog, because the clot itself may cut off the circulation and lead to necrotisation of the affected area, in the case of extremities. However, a clot from the extremities that loosens and moves through the dog’s system is an even larger risk, because it can lodge in or near to a major organ and lead to a stroke or other serious and acute condition.

If you suspect your dog may have developed a thrombus, try to keep them as still as possible and contact your vet immediately. Your vet will advise you on how to get the dog to the clinic safely and with the minimum of potential movement, and will then work quickly to administer a combination of blood thinners and fluid therapy.

This will help to thin and break down the clot and allow the system to flush it out, under careful supervision.

Treating a thrombus is risky, both in dogs and people-whilst they cannot always be prevented due to their connection to certain health conditions, keeping your dog mobile and encouraging them to stretch and move regularly (unless your vet advises otherwise) will all help.