ASH review series Flashcards
Perioperative management of congenital Factor VII deficient patient
Recombinant Factor VIIa
Acquired hemophilia mixing study result
No correction. (Not a congenital factor deficiency, acquired antibody)
Factor XII deficiency presentation
Don’t bleed
Differential for isolated prolonged PT-INR
Mild liver disease →
Congenital factor VII deficiency or acquired factor VII inhibitor → otherwise healthy person +
mild vitamin k deficiency →
Anticoagulant (VKA, direct thrombin inhibitor, ) →
polycythemia (artificially prolonged PT) →
APS (false positive) –>
Differential for prolonged PTT in patient with abnormal bleeding and in patient with no bleeding history
ABNORMAL:
Acquired VWS →
Factor 8, 9, or 11 deficiency →
Factor 8, 9, or 11 inhibitor
NO bleeding:
Factor XII
Lupus anticoagulant
Differential for prolonged PTT + PT
severe liver disease
DIC
*severe vitamin k deficiency
*common pathway defects – factor X deficiency or inhibitor + factor V inhibitor
Perioperative management of factor VIII heterozygote
- check baseline factor level
- if in normal range, no prophylactic therapy
Enzyme that affects Xa inhibitor concentrations (drug interactions)
CYP3A4
enzyme affecting wafarin concentrations
CYP2C9
Conditions associated with acquired VWS
MPN →
Plasma cell dyscrasias ->
Lymphoproliferative disorder →
Intrinsic pathway measured by what
PTT
What is serum?
Plasma minus clotting factors
Do coagulation tests use plasma or serum? What are collection tubes manufactured to contain anticoagulants?
1) Plasma. Plasma is unclotted blood (separated from buffy coat and RBCs) so contains clotting factors. Can’t use serum because all the clotting factors have been used up.
2) Preserve clotting factors
Why is it referred to as extrinsic pathway?
Activated by an extrinsic factor (eg tissue factor)
Utility of INR
- primary intended for titrating warfarin
- It has no predictive value for bleeding risk in patients not on warfarin per Dr. Shatzel
