3. Vein catheterizarion. Blood transfusion

Question 1

Handling venous catheters. Without 3-way stopcock

Answer 1

• Protect the catheter with temporary bandage
  during infusion
• After closing the catheter, flush with diluted
  heparine through the top injection site
• Maintain aseptic conditions!!!

Question 2

Blood transfusion

Answer 2

What blood component is deficient in the patient?
Cells:
- RBC
- Platelets
- (WBC) - usually not an indication for blood transfusion

Proteins:
- clotting factors
- (albumin) - usually colloid solution is applied
- (immunoglobulins)

May be multiple, i.e. RBCs + clotting factors (exsanguinated patient having rodenticide poisoning) or RBCs + platelets: exsanguinated patient having AITP (autoimmune thrombocytopenia)

Question 3

Blood transfusion. What preparation?

Answer 3

RBC transfusion
- Fresh whole blood
- Whole blood in CPDA
- RBC suspension in CPDA

Platelet transfusion
- Fresh whole blood
- Platelet rich plasma

Clotting factor transfusion
- Fresh whole blood
- Fresh frozen plasma
- (Frozen plasma: deficient in clotting factors 5, 8 anf vWF)

Question 4

Canine blood preparations

Answer 4

Question 5

Feline blood preparations

Answer 5

• There are no commercial small volume blood
collection kits

• Usually 40-50 ml fresh whole blood, aspirated into
~ 10 volmue % sodium citrate (4-5 ml)
~ heparinized syringe

Question 6

When to transfuse RBCs?

Answer 6

• Acute blood loss/hemolysis
~ PCV < 0.2 l/l in dogs, < 0.15 l/l in cats

• Chronic anemia
~ Absolute indication: PCV < 0.1 l/l
~ Relative indication: PCV 0.1-0.2 l/l
(Are there signs of hypoxia: tachycardia, tachypnoe)

Question 7

RBCs transfusions. Canine blood groups, cross matching

Answer 7

• most important blood groups: DEA 1.1, 1.2, 7
  ~ 40% of dogs are DEA 1.1+
• ideal blood donor group is DEA 1.1 negative
• there awe no preformed antibodies in the dogs -> first transfusion is not problematic
• antibodies develop in negative dogs within 1-2 weeks after incompatible transfusion. Perform cross matching/blood typing before repeated transfusion
  Major crossmatch: donor RBC vs. patient plasma
  Minor crossmatch: donor plasma vs. patient RBC

Question 8

RBCs transfusions. Feline blood groups, cross matching

Answer 8

• Most important blood groups: A, B, AB
~ 98% of domestic shorthair cats are of
blood group A
~ There are more blood group B cats in Persian,
British shorthair, Maine Coon breeds

• Cats have preformed antibodies against
incompatible blood group antigens
~ Blood group B cats: high anti-A antibody levels!
~ Do crossmatching/blood typing before
first transfusion

Question 9

RBC transfusion. Technical aspects

Answer 9

• Do not use expired, discolored, clotted products
• Handle with care, warm gently to body warm
~ Water bath / thermostate: ≤38 ºC
~ No microwave!!!
• Use human transfusion sets with clot filter for canine transfusions
• Never use the INFUSOMAT! (Only for watery infusions; haemolysis ! )
• Only dilute RBC suspensions with 0.9% saline if necessary
• Give slowly initially, monitor for complications:
temperature, respiration, allergic reactions, hemoglobinuria
• Try to finish the transfusion within 2-4 hours