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Flashcards in Exam 7 L. 3 Deck (21):

Indications for blood transfusion

1) temporary replacement of:
-plasma proteins/factors


Stored whole blood

1) older than 6 hours but less than one month
2) RBCs and plasma
3) does NOT contain: viable platelets, leukocytes, or labile clotting factors (i.e. FVIII, vWF, fibrinogen)
4) indicated when patient needs multiple blood components and volume


Packed RBCs

1) contains cells and small amount of plasma and anticoagulant
2) indications: anemia


Fresh frozen plasma

1) plasma separated from whole blood and frozen within 8 hours of collection (less than 1 year old)
2) contains: coagulation factors, anti-thrombin and other anticoagulation factors, vWF, albumin, globulins
3) Indications: coagulation disorders resulting in hemorrhage, prophylaxis before surgery in animal with known clotting factor deficiency

Note: do NOT use as a source of albumin! But, plasma can be used as a COLLOID to increase osmotic pressure!


Frozen plasma

1) plasma is FFP that has been stored >1 year but <4 years, or plasma separated from RBCs and frozen >8 hours after blood collection
2) contains stable coagulation factors: II, VII, IX, X, albumin
-good product for rodenticide patients!
3) indications: coagulation deficiencies of the above listed factors resulting in active hemorrhage


Plasma components

1) fresh frozen plasma: contains all clotting factors and plasma proteins
-broken down into cryo- precipitate and supernatant
2) cryo- precipitate: vWF, F VIII, fibrinogen
3) supernatant: vitamin K-dependent factors, globulins, albumin, AT, other proteins


Cryo- precipitate

1) contains: factor VIII, vWF, fibrinogen
2) best product for treating hemophilia a (F VIII deficiency), vWD, and fibrinogen deficient patients


Cryo- supernatant

1) contains: active clotting factors (except FVIII and fibrinogen) albumin, and globulin
2) indications: treatment of hemophilia B (FIX deficiency), vitamin K deficiency, oncotic support in hypoproteinemia


Canine blood types

1) 5 defined blood groups
-dog erythrocyte antigen 1.1, 3, 4, 5, 7
-DEA 1.1: positive, negative, or weak positive
-DEA 3, 4, 5, 7: positive or negative

NOTE: 95% of dogs have DEA 4! (Not only DEA 4, but have at least this one present)

-no preformed antibodies to DEA 1.1: allows us one free transfusion in the canine! (Cats do have preformed antibodies versus the opposite RBC type)


Universal dog blood donor

A dog that is DEA 4 positive only!!
-Commonly greyhounds


Major Crossmatch

Mix washed donor RBCs with recipient plasma
-agglutination = incompatibility**


How much blood to transfuse?

ml of blood = blood volume x weight (kg) x ([PCV desired - PCV recipient]/PCV donor bag)

Blood volume = 90 ml/kg for dog, 60 ml/kg cat

If they aren't destroyed, the transfused RBCs will last ~3 weeks


How fast to transfuse blood

No pumps!
1) reactions occur in approximately 10% of pRBC transfusions
2) 1 ml/kg/hr for 15 minutes
3) if no problems, increase rate to give over 4 hours (up to 10 ml/kg/hr)
4) monitor TPR every 30 minutes and watch for nausea, vomiting, diarrhea, agitation


Feline blood types

1) AB system
- Type A: most common
- Type B: uncommon, more in purebred cats
- Type AB
2)**high levels of naturally occurring antibodies to foreign antigens
- Type B cats have a strong reaction to type A blood!
- Type A cats have a mild reaction to type B blood
3)**no universal cat donor**


Mik antigen

1) common RBC antigen
2) Mik negative cats have endogenous Mik antibodies
-can result in hemolytic reaction, even if AB compatible
-for this reason it is recommended to crossmatch ALL cats


Acute immune hemolytic reaction (type 2 hypersensitivity)

1) stop the transfusion!
2) begin crystalloid infusion to optimize blood pressure and maintain renal perfusion

Note: if it is a type I hypersensitivity, you may see an allergic reaction ranging from hives to severe anaphylaxis
-stop transfusion and given antihistamine (i.e. diphenhydramine)


Acute immune-febrile non-hemolytic reaction

1) temperature increase of more than 1 degree C associated with the transfusion
2) slow transfusion, consider stopping
-consider an antipyretic drug


TACO: transfusion-associated circulatory overload

1) blood products have significant oncotic pull
2) monitored closely for signs of volume overload
-retching, vomiting, tachypnea, dyspnea
3) Lasix, oxygen as needed


Non-immune transfusion reactions

2) transfusion associated sepsis
3) non-immune mediated hemolysis: improper temperature exposure, mechanical hemolysis from pumps
4)*citrate toxicity*: HYPOCALCEMIA can occur from the anticoagulant in the blood product!


Volume overload

Give diuretics and oxygen!


Urticaria, pruritus, edema after transfusion:

Give diphenhydramine and dexamethasone (antihistamine and steroid)