SR 19 - Blood and Blood Products Flashcards Preview

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Flashcards in SR 19 - Blood and Blood Products Deck (43):
1

Define - PT

Prothrombin time
Tests extrinsic coagulation pathway (Warfarin)

2

Define - PTT

Partial Thromboplastin Time
Tests intrinsic coagulation pathway (Heparin)

3

Define - INR

International normalized ratio (reports PT results)

4

Define - PRBC

Packed red blood cells
One unit - 300mL
No platelets or clotting factors
Can be mixed with NS to infuse faster
Remember - RBCs have the antigens - so O is the universal RBC donor (they have no antigens for plasma antibodies to react against)
-/+ only really matters for girls who still may get pregnant at some point

5

Define - FFP

Fresh frozen plasma
Replaces clotting factors
No RBCs, WBCs, platelets
Remember - plasma has the antibodies - so AB is the universal plasma donor (Since they both antigents, they cannot have AB antibodies swimming around in their blood)

6

Define - Cryoprecipitate

Replaces fibrinogen, von Willebrand factors, some clotting factors

7

Which electrolyte is most likel to fall with the infusion of stored blood? Why?

Ionized calcium
The citrate preservative used for the storage of blood binds serum calcium

8

What changes occur in the storage of PRBCs?

Decreased Calcium
Decreased 2,3-DPG
Decreased pH
Decreased PMNs
Increased potassium
Increased hydrogen

9

What are generaly guidlines for blood transfusions?

Acute blood loss, history of CAD/COPD - Hb

10

Which blood type is the universal donor for PRBCs?

O negative

11

Which blood type is the universal donor for FFP?

AB

12

What is type and screen?

Determine blood type and screen for antibodies

13

What is type and cross?

Cross-matched with specific donor units for possible transfusion

14

Define thombocytopenia

Low platelet count

15

Common causes of thrombocytopenia in the surigcal patient?

Sepsis
H2 blockers
Heparin
Massive transfusion
DIC
Antibiotics
Spurious lab value
Swan-Ganz catheter

16

What can be given to correct platelet dysfunction from uremia, ASA or bypass?

DDAVP (desmopressin)
Leads to increased levels of coagulation factor (F) VIII, von Willebrand factor (vWF), and tissue plasminogen activator

17

What common medication causes platelets to irreversibly malfunction?

ASA
Inhibits cyclooxygenase

18

What is Plavix?

Clopidogrel
Irreversibly inhibits platelet P2Y12 ADP receptor
Blocks fibrin crosslinking of platelets

19

What platelet cout is associated with sponatneous bleeding?

20

How high should the platelet count be before surgery?

>50,000

21

When should 'prophylaxtic' platelet transfusion be given?

22

What is microcytic anemia 'until proven otherwise' in a man or postmenopausal woman?

Colon cancer

23

Why not infuse PRBCs with LR?

Calcium in LR may result in coagulation within the IV line
Use NS

24

How long can PRBCs be stored?

6 weeks (42 days)

25

What is the most common cause of transfusion hemolysis?

ABO incompatibility as a result of clerical error

26

What are the symptoms of a transfusion reaction?

Fever
Chills
Nausea
Hypotension
Lumbar pain
Chest pain
Abnormal beleding

27

What is the treatment for transfusion hemolysis?

Stop transfusion
Profide fluids
Perform diuresis (with lasix) to protect kidneys
Alkalinize urine with bicarb
Pressors as needed

28

What component of the blood transfusion can cause a fever?

WBCs

29

What is the transfusion 'trigger' Hct in young healthy patients?

21%

30

What is the 'optimal' Hct in a patient with a history of heart disease and stroke?

30%

31

When should ASA administration be discontinued preoperatively?

1 week
Platelets live for 7-10 days
(Use clinical judgement if patient is at risk for MI or stoke, may be better to continue the ASA and use excelelent surgical hemostasis instead)

32

What can move the oxyhemoglobin dissociation curve to the right?

Acidosis
2,3-DPG
Fever
Elvated Pco2

To the right means better unloading of O2 (Right = release)

33

What is the normal life of RBCs?

120 days

34

What is the normal life of platelets?

7-10 days

35

What factor is deficient in hemophilia A? What coagulation study is elevated?

Factor VIII
PTT

36

What is the preoperative treatment of hemophilia A?

Factor VIII infusion to 100%+ normal preoperative levels

37

What factor is deficient in hemophilia B? Elevated coagulation study?

Factor IX
PTT

38

What is von Willebrand's disease? Elevated coagulation study?

Deficiency of vWF and factor VIII-C
Autosominal dominant
Bleeding time

39

What is used to correct vWF deficiency?

DDAVP or cryoprecipitate

40

What is the effect on the coagulation system if the patient has a deficiency in protein C, protein S, or antithrombin III?

A hypercoagulable state

41

What is a 'left shift' on a CBC?

Juvenile polymorphonuclear leukocytes (bands)

42

What is the most common inherited hypercoagulable state?

Factor V leiden

43

What is Xigris?

Actived protein C
Which is used in severe sepsis