Transfusion Information For Veterinarians
Canine Blood Types
At least eight different blood types have been identified in the canine species. Some experts believe there are around 12 different blood types. Dog erythrocyte antigens (DEA) are determined by the different proteins and complex carbohydrates located on the cell membranes of the red blood cells. Blood types that have been identified as clinically significant include 1.1, 1.2, 3, 4, 5, 7 and any one dog can have one or all of these antigens. This is why it is so important to type the recipient. Using the Alvedia Qtest, this is done within two minutes in any clinical setting. The Qtest is still accurate even in the presence of agglutination and severe anemia. The cards are designed specifically to identify the 1.1 antigen, which is the most concerning. For the clinic situation, canine blood types are broken down into just two simple groups, DEA 1 negative and DEA 1 positive. At HemoSolutions the “universal” blood is negative for all antigens except DEA 4. The chances of the blood causing a transfusion reaction are virtually non-existent. The in-house typing systems (Alvedia) are not recommended to determine the blood type of the donor, but to determine if the recipient is positive or negative for the DEA 1 antigen. DEA 1 positive recipients should receive DEA 1 positive blood. Therefore the DEA 1 negative blood can be reserved for the true negative recipients and the trauma cases when there is no time to type an animal.
Feline Blood Types
Cats have naturally occurring alloantibodies to the other blood groups even without prior transfusion. Therefore, typing cats is extremely important and if not done, can lead to a fatal transfusion reaction. There are only three blood types in the feline population. A, B, and AB. There is also an MIK antigen that has surfaced; its relevance is not entirely understood at this time. This antigen does present an even more sound reason for crossmatching all feline recipients regardless of their transfusion history. Most cats in the US are Type A. If Type A blood is given to a Type B recipient, even the first time will result in a severe life-threatening hemolytic transfusion reaction. If Type B blood is given to a Type A recipient, it will not cause the life-threatening situation, but may shorten the life span of the RBC.
Preparing to administer Fresh Frozen Plasma
Always thaw the plasma in a warm water bath at 37c, DO NOT MICROWAVE. The bags are extremely fragile and if tossed around can crack, contaminating the plasma. Studies show that administering plasma to a hypothermic patient will actually inactivate the enzymes necessary for the initiating the intrinsic and extrinsic coagulation cascade. Therefore, be sure your patient is normothermic. Always complete the transfusion within 4 hours and always use sterile technique when hooking up a system. Blood products are an excellent medium for bacteria growth. With any blood product, use a blood administration set with at least 170 micron filter. This will filter out any aggregates or fibrin debris.
Preparing to administer Packed Red Blood Cells
Warm the blood to room temperature before the transfusion. Do not exceed 38C, this will cause hemolysis. Use an administration set with a filter of at least 170 microns to remove micro clots and debris such as white blood cells, fat and micro aggregates of platelets. If the transfusion is too slow, then check the filter, chances are it is clogged. Do not force the red blood cells through the filter as it will cause hemoylsis. Change the filter, or get a new administration line. During administration, do not use with Lactated ringer solutions which can cause coagulation to occur. Do not use 5% dextrose, osmolarity difference will cause hemolysis. Only 0.9% saline can be administer in the same line. Use sterile technique when connecting and disconnecting the administration line at the catheter site. The administration set should be replaced every 4 hours when a patient is receiving multiple transfusions. Always rock gently as handling the product roughly can also result in hemolysis.
Troubleshooting Migration Problems with the Alvedia Blood typing Kit.(Documentation directly from Alvedia in France.)
Click on the PDF link and read how to troubleshoot the absence of migration of red blood cells along the strip.
If you find you do not have enough donor sample to cross match when using the DMS rapid crossmatching kit, follow these instructions from DMS laboratories.
CM Directions (19 KB)