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Can dogs get blood transfusions?

Yes, dogs suffering from severe blood loss or blood diseases can receive blood transfusions to help them recover. The decision to transfuse is based on the overall clinical assessment of the dog’s history and clinical signs, laboratory test results and underlying cause of the blood deficiency.

Transfusions can be risky due to the chance of a life-threatening reaction. They should only be performed when the need is clear and other alternatives for treatment have been explored.

The most common indication for a transfusion in dogs is anemia, which is a low red blood cell count. A test called a hematocrit or packed cell volume (PCV) measures the percentage or red blood cells present in whole blood. When separated from the serum, a normal PCV is between 35 to 45 percent. Depending on the type, degree and course of the anemia, a transfusion with blood products, such as stored packed red blood cells or fresh or stored whole blood, may be indicated.

Dogs with rapidly progressive anemia need to be transfused earlier, when the PCV is still around 20 percent, while dogs with chronic anemias may do well at lower hematocrits, as long as they are not stressed. If a dog needs to undergo surgery anesthesia and surgery, the PCV should be at least 15 to 20 percent to assure proper oxygenation during the procedure.

Red blood cell transfusions have proven to be lifesaving in cases of immune-mediated hemolytic anemia (IMHA). This is a condition where the body suddenly views its own red blood cells as foreign and acts to destroy them. There is no evidence that giving transfused red blood cells would “add fuel to the fire” and speed up the destructive process, as previously thought.

Fresh frozen plasma (FFP) is most commonly used to treat blood-clotting disorders, as it contains all the coagulation factors. Hemorrhage caused by liver disease, anticoagulant rodenticide intoxication (rat-poison ingestion) and hereditary clotting diseases, such as von Willebrand’s disease, are conditions that can be treated with FFP. Although the benefits of using FFP for treatment of canine parvovirus, pancreatitis and disseminated intravascular coagulation are not definitive, there may be some response when treating these difficult cases.

Do dogs have different blood types?

Over a dozen different dog blood types have been identified so far. It is expected more will be found as research continues.

Blood types in dogs are genetic with complex inheritance patterns. Each blood group is inherited independently, which means that a dog could have any combination of the 12-plus blood groups. This creates variability in which blood types are most common, depending on the breed of the dog and the geographic region.

Even though there are many dog blood types and possible combinations, the one called “dog erythrocyte antigen 1.1” (DEA 1.1) is the most medically important. Approximately 40 percent of dogs are positive for DEA 1.1, meaning that they have that antigen in their red blood cells.

If a dog is DEA 1.1-negative and is given DEA 1.1-positive blood, the dog may develop antibodies that rapidly destroy the red blood cells if a second DEA 1.1-positive transfusion is given. By selecting donor dogs that lack DEA 1.1 or that match the recipient, the risk of sensitizing the recipient can be minimized. A DEA 1.1-positive dog may receive either positive or negative blood.

What is the best blood type for dog blood donations?

Dogs that are DEA1.1-negative are preferred for donating blood because their blood can be safely transfused into dogs that are either negative or positive for DEA 1.1. However, DEA 1.1-negative dogs are not truly “universal donors” because a dog may be positive for another blood type that might cause an issue.

To be sure there will not be a serious immune reaction to any of a donor dog’s blood types, the veterinarian will do a test called “crossmatching.” This test checks the overall compatibility of donor and recipient blood.

After confirming DEA 1.1 blood type and running a crossmatching test, a veterinarian can typically determine which type of blood will be the most successful for the dog receiving the transfusion.

What are the other qualifications for dogs donating blood?

In a true emergency, theoretically any dog could donate blood. However, some dogs are better suited to be blood donors.

Other than the DEA 1.1-negative blood type, there are a few more factors that are preferred when choosing a blood-donor dog.

The ideal dog for donating blood is more than 50 pounds and at a healthy weight for its size. Larger dogs can donate a larger volume of blood more easily and frequently than smaller dogs. Adult dogs under the age of six make good donor candidates. A dog can usually donate blood five to six times a year.

Donor dogs should be up to date on their vaccines and healthy with no heart murmur. These dogs should not be on any medication and free of infectious diseases, parasites and blood-borne diseases, such as heartworm or Lyme disease.

Calm dogs are preferred. In order to give blood, dogs must be able to sit quietly for 10 to 15 minutes while blood is being collected. One pint of blood can help save four dogs.

What is the process for blood transfusions in dogs?

The first step is to locate a source of appropriate blood. There are two ways veterinarians can obtain blood for a transfusion. They can pull blood from a cooperative canine donor or contact a pet blood bank and request blood. Veterinarians can also order from national pet blood banks, and many local emergency and specialty hospitals have their own pet blood banks.

The blood types of both dogs must be crossmatched before starting the transfusion. The veterinarian will take a sample from the dog receiving the transfusion to check for an immune response to a sample of blood taken from the donor dog. This process is then reversed.

This is an important step because giving DEA 1.1-positive blood to a dog that is DEA 1.1-negative can cause the immune system to attack the newly transfused blood cells. This can result in a serious allergic reaction.

Blood from a blood bank as well as blood obtained directly from a donor dog is stored in special bags with additives that keep the blood from clotting. When it is time to use the blood for a transfusion, these bags are hooked up to an intravenous fluid line that has a special filter built in. The blood transfusion is given directly into the vein through an intravenous catheter usually placed in the front leg or jugular vein of the recipient dog.

The total dose of blood to be transfused is based on the size of the dog and how much blood it has lost. The transfusion is given over a specific time period, during which the dog is closely monitored to ensure it is not having any kind of reaction.

The most common sign that a dog is having a reaction to the transfusion is fever. This may be followed by vomiting and hemolysis, which is the rapid destruction of red blood cells. While the fever and vomiting usually subside, reactions involving hemolysis can be fatal.

Dogs that have received a transfusion should be monitored for 24 to 48 hours for a delayed hemolytic reaction. A red blood cell level is checked immediately after the transfusion and again eight hours later. The patient should also be monitored for any changes in breathing or urination.

In most cases, a single transfusion is all that is needed to help the dog recover. For some diseases where there is ongoing blood loss or destruction of red blood cells, the dog may need repeated blood transfusions.