Pulmonary thromboembolism describes an occurrence of the development of blood clots that occlude blood vessels, are lodged in pulmonary arteries, and end up blocking blood flow to these pulmonary arteries. Pulmonary thromboembolism, abbreviated as ‘PTE’ causes difficulty in breathing and can be fatal, leading to sudden death.
Blood clots, as previously stated, play a major role in this condition. It has also been discovered that in dogs that have died from immune-mediated hemolytic anemia, blood clots present in the lungs have been found. The factors that cause blood to clot, known as clotting factors, are found in the liver. These help to ‘seal up’ blood vessels that have been torn or worn out using platelets and red blood cells. Blood circulation to the lungs via arteries and veins means that the blood must flow slowly.
Immune Mediated Hemolytic Anemia (IMHA) causes the clotting cascade to begin, meaning that these clots will take place in the lung. As the clots form, thromboembolism may occur, causing red blood cells to die and gives the liver more work to do.
An imbalance in clotting and bleeding occurs in the lungs causing pulmonary thrombosis because the liver fails to produce enough clotting factors.
Causes of pulmonary thromboembolism
For animals, deep vein thrombosis does not occur as often as it does in humans, but when it does, it causes a high risk of a blood clot obstructing the lungs, causing pulmonary thromboembolism (PTE) in dogs.
However, pulmonary thromboembolism occurs secondary to other ailments. Dogs that clot easily can develop pulmonary thromboembolism. There are underlying diseases that could cause this condition like;
- Severe trauma
- Blood stasis in the heart vessels
- Kidney disease
- Kidney disease
- Diabetes mellitus
- Administration of steroids
- Immune-mediated hemolytic anemia
Signs and symptoms of pulmonary thromboembolism in dogs
Objective ways the veterinary doctor can detect thromboembolism in dogs include; tachypnea, emesis, panting, weakness, spontaneous bruising, loss of appetite, and increased respiratory rate.
Some subjective observations include dark urine, yellow eyes, blue-tinged or pale gum, bloody cough, and sudden death.
Breeds specific to pulmonary thromboembolism are the Old English Sheepdog, Saluki, Poodle breeds (Miniature Poodle, Toy Poodle, and Standard Poodle), and Springer Spaniel.
Common Treatment Protocol
The first treatment protocol is to stabilize your dog. This means that the veterinarian will introduce oxygen therapy to prevent further blood clots and supportive care.
Then the veterinarian will treat the underlying problem like quite a few have been mentioned as causes. For example, immune-mediated diseases are treated with corticosteroids and immunosuppressants if the ailment warrants it.
Anticoagulants or blood thinners like warfarin and heparin are medications that the veterinarian can recommend to manage blood clots. Also, clopidogrel and aspirin (antiplatelet) can be used as preventive medication for these dogs, especially those at high risk of pulmonary thromboembolism.
Transmission of blood may be required in severe cases or the spleen may be removed. Whatever the case, relapse may occur. Therefore, monitoring by the veterinarian is required via follow-up visits.
Stem cell therapy
At Safari Veterinary Care Center, dramatic positive results have been observed from administering stem cell therapy to dogs with blood clots in the lungs secondary to immune-mediated hemolytic anemia. These stem cells completely resolve blood clots by growing new blood vessels, and vessels blocked by blood clots are recanalized.