2005 Year in Review

Blood Donation: Pets, Too, Can Give the Gift of Life

Source: Dr. Rachael Carpenter; Veterinary Extension/Office of Public Engagement; University of Illinois College of Veterinary Medicine; 217-333-2907; Author: Kim Marie Labak

An archive of pet columns from the University of Illinois College of Veterinary Medicine is on the Web at Pet Columns.

When cats and dogs suffer from severe blood loss or blood diseases, transfusions of whole blood, plasma, or platelets collected from other pets can save lives.

According to Dr. Rachael Carpenter, veterinarian at the University of Illinois Veterinary Teaching Hospital in Urbana, most transfusions are of whole blood that contains red blood cells. Red blood cells carry oxygen throughout the body. Anemia, a shortage of red blood cells, can be life-threatening if it becomes severe.

An animal may lose red blood cells and become critically anemic from external or internal bleeding caused by traumatic injury, from ingestion of toxins such as rat poison, or from autoimmune diseases in which the immune system attacks red blood cells. Excessive blood loss can occur during complex surgical procedures, such as removal of a large tumor.

Geriatric patients may suffer anemia, especially if they have kidney disease that reduces the production of erythropoietin, the hormone that stimulates the bone marrow to produce blood cells.

Transfusions of whole blood can increase the red blood cell count, increasing the blood's capacity to carry oxygen. Whole blood is considered "fresh" if it is used within 4 to 6 hours of being donated. Whole blood can be refrigerated and stored for up to 21 days, but it cannot be frozen for later use since freezing destroys red blood cells.

Other blood products that can be transfused include plasma and platelets. Plasma can be used to treat inflammatory disease or coagulative disorders, and platelet transfusions are used, as they are in human medicine, to aid blood clotting. Unlike whole blood, plasma can be stored frozen for up to a year.

Whereas people have four blood types, dogs have around fifteen and cats have three. Dogs with type A negative blood make the best donors. A cross-match to test for a negative reaction is usually performed prior to a transfusion. Interestingly, up to 70 percent of greyhounds are A negative, compared with a much smaller percentage of the general dog population.

For cats, blood typing before a transfusion is crucial to prevent adverse and potentially fatal reactions to foreign blood antibodies.

As with human blood donation, every effort is made to ensure that the blood supply is clean and free of disease. At the University of Illinois College of Veterinary Medicine, donors undergo a complete work up with a physical examination, blood chemistry tests, and infectious disease screening. The blood is also typed.

When a pet needs a transfusion, the blood can come from a local blood bank, a reserve of blood products kept at a veterinary clinic, or directly from another donor animal. In a busy referral practice, much blood is needed for emergency and oncology services. To meet the need at its teaching hospital, the University of Illinois College of Veterinary Medicine gratefully relies on a list of faculty, staff, and students who volunteer their pets as donors.

Veterinarians can also order blood products online from regional blood banks and get them shipped overnight. Some veterinary clinics and hospitals may have their own on-site reserve of refrigerated or frozen blood products. Veterinarians may also have a list of donors they can call for fresh blood donations when the need arises, or may use their own pets or other staff pets as donors.

Animal blood banks can experience shortages as human blood banks do, and some veterinary clinics may have donor programs. For more information about pet blood transfusions or blood donation, contact your local veterinarian.

by  Editor, theCity1.com
September 27, 2005