Chapter 25 Small Animal Medical Nursing Blood Transfusion

Chapter 25 -Small Animal Medical Nursing Blood Transfusion pgs. 793 -796 in the CTVT book The 1 st successful animal to animal blood transfusion was done by Richard Lower, Feb. 1665 between a Mastiff and a mixed breed dog.

Technicians Today, technicians are taking a more active role in transfusion medicine by preparing the product for administration, monitoring the transfusion recipient, and setting up blood donor programs, among other tasks.

Blood Transfusion Is an effective method of fluid replacement but a potentially hazardous form of treatment. Clear indication for its use must be present. The effectiveness of transfusion is temporary. Every effort must be made to identify and correct underlying problems.

Why Perform Blood Transfusions Severe blood loss (trauma, surgery) Chronic anemia (respiratory distress, weakness) Blood is used for its oxygen-carrying capabilities. Defects of coagulation. (Hemophilia, Von Willebrand disease) Use platelet rich plasma over blood. Autoimmune hemolytic anemia (in lifethreatening situations) PCV levels should not dictate giving a blood transfusion. While a PCV of 12% may be life threatening for one animal it may represent a totally different scenario for another patient.

Platelets Survive for less than 12 hours in stored blood, therefore freshly drawn blood should be used immediately. Platelet rich plasma is the preferred transfusion method when needing to replace platelets. (Note: use the same guidelines when performing a plasma transfusion as you would with a blood transfusion. )

Why use Platelets? Animals with abnormal platelet function Hereditary or acquired bleeding disorders: Hemophilia Von Willebrand disease (v. WD) Disseminated intravascular coagulation (DIC) pg. 832 -833 You want to provide adequate concentrations of the deficient coagulation factor at the bleeding site.

Microscopic view of platelets

Autoimmune Hemolytic Anemia The animal’s immune system actually attacks its own red blood cells leading to their destruction-hemolysis. The antibodies attack the cell membrane. Red blood cell transfusion is only administered in life-threatening situations, as the patient’s immune system will also attack and destroy these RBCs as well. If transfusion is necessary as a life-saving measure, only the absolute minimum number of RBCs should be administered. (12 ml/kg of body wt. )

Do you remember what WBCs are? The body’s army Fight off infections by increasing in numbers. They attack germs!

Leukopenia Low white blood cell (WBC) count Blood transfusions are impractical Hypoproteinemia Low serum protein Blood transfusions are impractical WBC RBC Platelet

Canine Blood Groups

Canine Blood Groups There are 19 + known blood groups in dogs, while there are 6 well characterized blood types known as dog erythrocyte antigens. DEA=dog erythrocyte antigen. Canine blood types are designated by the presence of specific DEAs. The antigens are DEA 1. 1, 1. 2, 3, 4, 5, and 7. Every dog is either positive or negative for these blood types. The blood type of most importance is DEA 1. 1 because of transfusion reactions. A good resource: www. rapidvet. com/help. htm Antigens=proteins

DEA 1. 1 DEA 3 DEA 7 DEA 4 Because this dog’s blood is positive for DEA 1. 1 transfusing into a dog that is negative for DEA 1. 1 could be fatal.

Blood-Typing A method of identifying the antigens (proteins and carbohydrates) on the surface of red blood cells. Samples can be sent out to a laboratory. Blood typing cards can be utilized. These cards can only detect DEA 1. 1 in dogs; and feline blood types A, B, and AB. The cards are easy to use but the results may pose difficult to interpret.

Blood Typing Cards Dogs have various proteins, also called "antigens", which are associated with the surface of red blood cells. In dogs, these proteins, rather than being associated with letters to distinguish them from each other, have been assigned numbers. Thus, we have the dog erythrocyte antigen (DEA) system of canine typing.

DEA 1. 1 Is the most antigenic and is associated with most blood transfusions. It is said that about 40% or more dogs are positive for the DEA 1. 1. Breeds more commonly DEA 1. 1 positive are Golden Retrievers and Labradors. Breeds more likely to be DEA 1. 1 negative are Greyhounds, Boxers, Irish Wolf Hounds, German Shepherds, Dobermans, and Pit Bulls.

Ideal blood Donor is Negative For DEA 4. Universal Blood Donor is Negative For DEA 1. 1 Some experts suggest that dogs may actually have 12 or more blood types.

Universal Dog Donor Universal Blood donors test negative for both DEA 1 alleles. Can you remember the numbers associated with this? These dogs should also test negative for heartworms, Ehrlichia canis, babesia canis and Haemobartonella canis.

Universal Donor The blood group of canines synonymous with the term “universal donor” is DEA 1. 1 and DEA 1. 2 negative.

Can my dog donate blood? Dogs that test negative for DEA 1. 1 can give blood to dogs that are DEA 1. 1 negative and DEA 1. 1 positive. These dogs are considered “universal blood donors”. Dogs that test positive for DEA 1. 1 can only give blood safely to dogs that are DEA 1. 1 positive.

Universal Recipients Dogs positive for DEA 1. 1 are considered universal recipients. Do you understand the difference between a donor and a recipient?

Feline Blood Groups

Feline Blood Groups 1) Blood group A is the most common in cats overall in the United States. 2) Blood group B is common in European breeds. (Devon rex, Abyssinian, British shorthair) 3) Blood group AB is rare. There is no universal feline blood donor. Blood typing and cross-matching should ALWAYS be performed on cats! Each and every time!

Cats naturally have antibodies against blood types that they do not have, meaning that mismatched blood can be fatal to them. Always blood type and crossmatch feline blood and blood products before administering. Do not transfuse canine blood or blood products to felines or vice versa.

Feline Blood Groups Although transfusing different blood types can be fatal in cats the following information was taken from an article in the Veterinary Technician magazine, July 2006. Type B cats have high anti-A alloantibodies Type A cats have weak anti-B alloantibodies, meaning that if transfused with B blood they will have a mild reaction to the blood and the RBCs will have a half-life of 29 to 39 days. Type B cats receiving type A blood; RBCs will be rapidly destroyed within a few minutes to hours. These cats will have severe reactions possibly followed by death. Type AB cats can receive either A or B blood with little to no clinical reactions.

Feline Blood Tying Cards

Crossmatching A laboratory test that predicts a transfusion recipient’s response to a donor’s RBCs and plasma by detecting any serum (plasma) incompatibility between the donor and the recipient. This is a two part test. Dogs do not have naturally occurring antibodies against blood types they lack, like cats do. It is more important to crossmatch than to blood type a canine recipient before transfusion.

Blood Crossmatching Procedure Step 1 MAJOR crossmatch Donor Blood + Recipient Plasma Positive Test=Macro or Microagglutination present (Incompatible) Negative Test=Macro or Microagglutination Absent (Compatible) Step 2 MINOR crossmatch Recipient Blood + Donor Plasma Positive Test=Macro or Microagglutination present (Incompatible) Negative Test=Macro or Microagglutination Absent (Compatible)

Macroagglutination Microagglutination with Rouleaux formation

Healthy red blood cells (upper left) are smooth and round. Hemolytic red blood cells (lower right). Minor CM: detects antibodies in the donor plasma directed against the recipients erythrocytes. Major CM: performed to detect antibodies in the recipients serum that may agglutinate or lyse the donors erythrocytes.

Auto-Agglutination Saline Test Purpose of test: Is your patient autoagglutinating. What does this mean? First, what does auto mean? What does agglutination mean?

Auto-Agglutination Saline Test Clumping of red blood cells within a patient’s own serum; can be caused by diseases such as IMHA formerly known as autoimmune hemolytic anemia. This test is included in the Rapid. Vet-H canine DEA 1. 1 test kit. No microscope required! This test can also be done with a drop of saline and a drop of blood (unspun from your purple top tube) on a microscope slide. You will need a microscope as well. Why do this you may ask? Remember the major and minor crossmatch?

Sudden death is unlikely in dogs during blood transfusions but can occur in cats.

Blood Collection Guidelines Collection site: jugular vein in cats & dogs Can be sedated, but not necessary in dogs. Sedation is common in cats Surgical aseptic preparation of the collection site is performed Clean stick and rapid withdrawal is preferred due to clotting Do you need to use some sort Read CTVT pgs. 793 -796 of anticoagulant?

As blood is collected, it should be mixed gently in a back and forth motion as seen below. After the donor dog has been clipped and surgically prepped, the collection needle is inserted into the jugular vein.

Administering Blood and/or blood products Should be gradually warmed to room temperature. Never place in a microwave! Once a blood container has been opened it should be used within 24 hours. Use a micropore filter to reduce microemboli. �

Blood Products Whole Blood (FWB=Fresh whole blood, <8 hours old) (SWB=Stored whole blood, >8 hours old) Packed Red Blood Cells (p. RBCs) Plasma (FFP=Fresh Frozen Plasma) Platelet-Rich Plasma (PRP) Cryoprecipitate

Cryoprecipitate This is the cold, insoluble portion (slushy) of plasma that precipitates after FFP has been thawed slowly in the refrigerator. Cryoprecipitate contains von Willebrand factor, fibrinogen, and factor VIII and is used to treat this disease as well as hemophilia A, and fibrinogen deficiencies.

Blood Collection Systems

This is an example of a “Closed system of blood collection”. The components of blood are spun down but not separated into satellite bags. This type of system allows for collection, processing, and storage of blood and blood components without exposing them to the environment, therefore reduces the risk of bacterial contamination. This system is most often used with dogs.

The components of blood have been separated and transferred to satellite bags. WOW: FFP contains coagulation factors and plasma proteins. Long-term plasma can be stored for 4 yrs. at -4º F to -22º F

Open System Disadvantage: blood and blood components are exposed to the environment. This type of system is most commonly used in cats and often used with dogs.

Cont. Blood Collection Systems Use of glass bottle blood collection systems should be avoided since they are not closed systems and allow the blood to be exposed to room air. Glass bottles also cause platelet inactivation and clumping on contact with the glass surface. CTVT pg. 794

Blood and blood products are always administered slowly and intravenously through a sterile bloodadministration kit.

Donor Guidelines Good general health and temperament 1 to 8 years of age Easily accessible venipuncture site No infectious diseases No medications (except heartworm or flea preventatives) No history of pregnancy Females must be spayed. Annual blood work.

Ideal Canine Blood Donors 50 lbs or more Medium build Disease free/in good health Good temperament Negative for heartworms Current on vaccines Minimal PCV of 40%

Ideal Feline Blood Donors Disease free/in good health Current on vaccines Heartworm neg. Good temperament 8 lbs or more but not overweight Minimal PCV of 35%

Just how much blood can you take? 10 to 20 ml of blood per kilogram of body weight may be drawn every 3 weeks from the canine donor. 60 ml can be drawn every 3 weeks without excessive stress to the feline donor. Some clinics will only allow their donors to donate blood every 4 to 5 weeks.

Acute Blood Transfusion Reactions • • • Hyperthermia Vomiting Tachycardia Tachypnea Weakness Muscle tremors • • • Facial swelling Agitation Vocalizing Hypotension Hemoglobinemia Hemoglobinuria Although acute reactions are rare, they are considered The most serious!

Food, Water and Meds Because vomiting is a potential adverse reaction to a transfusion, food, water, and medications should be withheld from the patient during the transfusion. Be sure to ask the DVM when food and water can be reintroduced to the animal.

Antihistamines Diphenhydramine hydrochloride may be administered to the patient 30 minutes prior to transfusion to reduce the risk of blood transfusion reactions. What is the Common name For this drug?