ITE Heme Flashcards

1
Q

Antibody screen negative meaning

A

PATIENT has no sig RBC antibodies

*the RBC has surface antigens (A, B, Rh)

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2
Q

the RBC has surface antigens (A, B, Rh), which one is most likely to produce immunization?

A

Rh

- if pts are Rh(D) negative, they do not express Rh(D) antigen on their RBC surface

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3
Q

What does it mean if a patient is type A blood?

A

They have A antigen on their RBC surface
- can accept type A and O blood

They lack B antigen

  • would make anti-B antibodies
  • If transfused with nonmatching blood, their antibodies will attack donor blood -> massive hemolysis
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4
Q

How does type and cross work? How long does it take?

A

Mixing DONOR erythrocytes with RECIPIENT’S plasma
- Agglutination occurs if there is a minor or major incompatibility

Takes 45-60 min

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5
Q

Universal donor

Universal recipient

A

Type O

Type AB

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6
Q

How does type and screen work?

A

Determines pt’s ABO and Rh(D) status

Mixes PATIENT’S plasma with 2-3 reagent samples of RBCs (clinically important RBC antigens)

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7
Q

If type and screen is already performed and the patient emergently needs blood, _________ is the best option if a full cross match (50 min) cannot be performed.

A

type-specific partially cross-matched blood transfusion

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8
Q

All blood in the US contains ____ that serves as a buffer,
____ that acts as a RBC energy source, and
_____ that acts as an anticoagulant

A

Phosphate
Dextrose
Citrate

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9
Q

How long can pRBCs be stored for?

A

21-35 days

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10
Q

What anesthetics will trigger acute attacks in porphyrias? (8)

A
  1. Etomidate
  2. Benzos
  3. Ropivacaine
  4. Phenytoin
  5. Sulfonamides
  6. Ethanol
  7. Amphetamines
  8. Ergot derivatives

*fent, prop, gas are okay

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11
Q

TEGs - What do you give if:

  • R time is too long
  • a- angle is too low
  • Max amplitude too high
  • Breaking down clot too quickly (hyperlytic)
A

R time: FFP

  • clot beginning to form
  • has clot products (IX, X

a-angle: Fibrinogen

  • how quickly clot is forming
  • often given with FFP

MA: Platelets

  • width of clot
  • Maximal clot strength

Antifibrinolytic (TXA or aminocaproic acid) to prevent lysis
- clot lysis speed

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12
Q

TEGs: appropriate values

  • R time
  • a- angle
  • Max amplitude
  • Clot break down time, LY30
A

“Rule of 6’s”

  • R time: 6 min
  • a- angle: 60 degrees
  • Max amplitude: 60 mm
  • LY30 (Clot break down): 6%
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13
Q

Cryo has what factors in it?

A

VII, vWF

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14
Q

MOA of TXA?

A

Antifibrinolytic

  • direct plasminogen and plasmin inhibitor
  • prevent fibrin break down
  • control of hemorrhage
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15
Q

MOA of protamine

A

antidote to heparin

Chelates large, negatively charged heparin molecule and prevents binding with antithrombin 3

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16
Q

MOA of vitamin K clotting cofactor

A

Increases activation of clotting factors 1972 (X, IX, VII, II)
- cofactor for those factors

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17
Q

tPA MOA? Effect on TEG?

A

accelerates fibrinolysis

  • (enzymatic catalyst for conversion of plasminogen to plasmin -> binds fibrin -> breakdown)
  • increased LY30 (clot break down). (normal is 6%)
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18
Q

TXA or aminocaproic acid MOA?

A

Antifibrinolytic.

- Lysine analog that directly binds to activated plasmin in the place of fibrin -> prevents fibrin breakdown

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19
Q

tPA can cause hemorrhage d/t increased fibrinolysis. How do you reverse tPA?

A

antifibrinolytic like TXA or aminocaproic acid

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20
Q

Protamine MOA

A

large, positively charged molecule that chelates large negatively charged heparin and prevents binding with AT3 and subsequent anticoagulant effect

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21
Q

Desmopressin (DDAVP) MOA

A

induces synthesis and release of VWF by endothelial cells

- critical role of platelet adhesion

22
Q

What is contraindicated in Acute intermittent porphyria?

A

anything that induces P450 d/t increasing ALA concentration

  1. Alcohol
  2. Barbiturate
  3. BDZ
  4. Nifedipine
  5. Glucocorticoids
23
Q

How does fructosamine testing in diabetes work? Who is it used in?

A

Measures shorter time interval compared to hgb A1c.

Pts who have reduced red cell lifespans (hemolytic anemia, sickle cell disease)

24
Q

How can the sequestration of platelets spare autologous blood products from damage during CPB?

A

This creation of a platelet-rich plasma can help protect the platelets from damage during bypass.

Infuse platelets after bypass to conserve blood

25
Q

Dietary supplements that interfere with platelet function (4)

A
  1. Garlic
  2. Ginger
  3. Ginko
  4. Vit E
26
Q

St John’s Wort is used to tx depression and PMS. Drug interactions?

A

Potent CYP3A4 inducer -> increased metabolism and decreased efficacy of meds

  • Digoxin
  • Warfarin
  • Cyclosporin
  • Anticonvulsants
27
Q

(Right/Left)ward shift of oxyhemoglobin dissociation curve is found in pts with chronic severe anemia

A

Rightward

- decrease affinity of hgb for oxygen -> facilitates release of oxygen to tissues

28
Q

Can pts develop cardiomegaly in chronic severe anemia?

A

Yes - high outpt cardiac failure secondary to decreased blood viscosity

  • Pulm congestion
  • Ascites
  • Edema
  • Orthopnea + dyspnea
29
Q

In general, a positive direct antiglobulin test (Coombs test) is diagnostic for _____

A

a hemolytic reaction

- if negative, then pt has non-hemolytic rxn

30
Q

Transfusion related acute lung injury (TRALI) - leading cause of transfusion related death usually w/in 6 hours
- What is it d/t?

A

Antibodies in donor blood bind to recipient’s leukocytes -> adhere to vascular capillary bed in pulmonary circulation

31
Q

________ is the most common blood reaction. Fever, chills, headache, myalgias

A

non-hemolytic febrile transfusion reaction

  • negative Coombs test
  • Recipient antibodies against HLA antigens on donor leukocytes -> cause lysis of donor leukocytes
32
Q

Polycythemia vera is a hematological condition that causes which blood cell lines to proliferate?

A

All three

  • Erythrocytosis
  • Leukocytosis
  • Thrombocytosis
33
Q

Mild allergic transfusion reactions (urticaria, pruritus, facial swelling) are d/t?

A

Soluble foreign proteins in transfused donor blood

- acts as antigen -> immune activation in recipient via IgE response

34
Q

In pts with sickle-cell disease, with mod-high risk procedures, you should transfuse to hgb level of ___

A

10 g/dL

35
Q

Which more commonly causes HIT, Unfractionated heparin or LMWH?

A

Unfractionated

- 10x more

36
Q

Two tests that can detect HIT. Which one is more sensitive? Specific?

A
  1. Anti- Platelet factor 4
  2. Serotonin release asay

Both are sensitive

SRA is more specific

37
Q

When does an acute hemolytic transfusion reaction occur? (immediate, N/V, chills, fever)

A

When previously sensitized individual with circulating antibodies to either A or B antigens on donor erythrocytes is transfused blood containing that major antigen.

38
Q

Tests to run if you suspect hemolytic transfusion reaction?

A
  1. Direct antiglobulin (Coombs) test
  2. Repeat crossmatching
  3. Hemolysis tests (haptoglobin, bilirubin, urine hgb)
39
Q

Indication for platelet transfusion in the setting of massive transfusion is ____

A

< 75,000/mcL

40
Q

Tope 3 causes of death associated with blood products

A
  1. TRALI
  2. Hemolytic transfusion reactions (non-ABO > ABO)
  3. Infection/Sepsis
41
Q

PCWP is a measure of the LAP.

  • Normal PCWP: ?
  • What is it in pts with TRALI?
A

5-12 mmHg

<18 mmHg

*FYI: CHF and pulmonary edema pts have PCWP > 25mmHg

42
Q

What can help differentiate TRALI from TACO since they both can cause b/l pulmonary infiltrates?

A

BNP - elevated in TACO

43
Q

What can be given to pts with heparin resistance (antithrombin III deficiency)?

A

FFP or antithrombin III

44
Q

Maximum allowable blood loss equation

A

[EBV * (starting Hct - target Hct)] / (starting HcT)

ie:
= [70ml/kg x 70kg * (42 - 30)] / 42
= [4900 mL *12 ] /42

45
Q

Cryoprecipitate contains ____ mg/unit of fibrinogen.

A

200 mg/u

  • ie: if you give 10 u of cryo, you are giving pt 2000mg of fibrinogen
46
Q

Cryoprecipitate has factors ____

A

VIII, fibrinogen, vWF

47
Q

What is leukoreduction of blood products? Benefits?

A

Decrease or complete elimination of donor leukocytes in blood components
- reduces risk of febrile transfusion rxn and risk of viral transmission (CMV)

*does NOT prevent graft vs host disease and some bacteria

48
Q

Tx for TACO

A

diuretics

- problem is overload in circulating volume regardless of type of blood product

49
Q

Warfarin reversal for urgent surgery

  • INR 1.5 - 1.9:
  • INR 1.9 - 5:
  • INR 5 - 9:
A
  • INR 1.5 - 1.9: PCC
  • INR 1.9 - 5: PCC or FFP + 1-3mg of IV vit K
  • INR 5 - 9: PCC or FFP + 2-5 mg IV Vit K
50
Q

Warfarin reversal for surgery (24-48h later):

  • INR 1.5 - 1.9:
  • INR 1.9 - 5:
  • INR 5 - 9:
A

Warfarin reversal for urgent surgery

  • INR 1.5 - 1.9: 1mg PO Vit K
  • INR 1.9 - 5: 1-2.5 mg PO Vit K
  • INR 5 - 9: 2.5 - 5mg PO Vit K