Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
34 Cards in this Set
- Front
- Back
|
How is primary hemostasis best evaluated (2)?
|
Platelet function tests
vWF studies |
|
|
What is Osler-Weber-Rendu HHT?
|
HHT = Hereditary Hemorrhagic Telangiectasia
Autosomal dominant disorder Telangiectasias on face, mucous membranes, liver, brain Frequently complicated w/ epistaxis and GI bleeds |
|
|
What is the most common inherited bleeding disorder?
|
Von Willebrand Disease
|
|
|
How is Von Willebrand Disease inherited?
|
Autosomal dominant
|
|
|
Differences in Von Willebrand Disease types (1 through 3)
|
Type 1 - decrease in vWF
Type 2 - defective vWF (1 defective gene (heterozygote)) Type 3 - NO vWF (2 defective genes (homozygote)) |
|
|
How are vWF and Factor VIII related?
|
vWF carries Factori VIII
SO, in severe vWD, there is a very low Factor VIII level |
|
|
Ranking of blood types according to baseline levels of vWF
|
AB > A > B > O
|
|
|
What is 1st line therapy for VWD?
What does it do? |
Desmopressin
Releases vWF stores from endothelium NOTE: NOT all pts. respond NOTE: tachyphylaxis after 2-3 doses |
|
|
What drug is used in supportive therapy for vWD?
What does it do? |
Amicar
Stabilizes clots |
|
|
What treatment is given to desmopressin non-responders?
|
vWF concentrates
|
|
|
In addition to the liver, what else makes Factor VIII?
|
Endothelial cells
|
|
|
In addition to the liver, what else makes Factor V?
|
Megakaryocytes
|
|
|
In addition to the liver, what else makes Factor III?
|
Monocytes
Smooth muscle Endothelium |
|
|
Which clotting proteins are K-dependent (6)?
|
Factors II, VII, IX, X
Prothrombin Protein C |
|
|
What is the role of Vitamin K in clotting?
|
Involved in carboxylation of Gla residues
Gamma-carboxy Gla is required to bind Calcium |
|
|
Which type of hemophilia is NOT sex-linked?
|
Hemophilia C
It is autosomal recessive |
|
|
How are Hemophilia A & B inherited?
|
X-linked Recessive
|
|
|
Hemophlia A involves abnormalities of what factor?
|
Factor VIII
|
|
|
Hemophilia B involves abnormalities of what factor?
|
Factor IX
|
|
|
What is the most common type of hemophilia?
|
Hemophilia A (80 - 95%)
|
|
|
Comparisons of severities of hemophilia
|
---Mild---
Very rare spon. bleed, bleed w/ MODERATE trauma ---Moderate--- Unusual spon. bleed, bleed w/ MINOR trauma ---Severe--- Common spon. bleed, excessive bleeding w/ MINIMAL trauma |
|
|
What is the dominant clinical feature of hemophilia?
|
PROLONGED bleeding into joints, muscles, soft tissue
|
|
|
Abnormalities of what are involved in liver coagulopathy?
(clotting factors) |
F VII first, F VIII, Fib last
|
|
|
3 major problems assoc. w/ DIC
|
Thrombosis of small vessels causes end organ ischemia
Fibronylisis of thrombuses causes reperfusion injury Consumption of platelets and clotting factors cause bleeding |
|
|
Can a clotting factor deficiency be overcome in a mixing test?
|
YES
|
|
|
Can presence of a coagulation inhibitor be overcome in a mixing test?
|
NO
|
|
|
You have an isolated, prolonged PT
If 50:50 mixing corrects the PT, what could be wrong (3)? |
This means that there was a clotting factor deficiency
Factor deficiency (Factor VII) Vit K deficiency Liver disease |
|
|
You have an isolated, prolonged PT
If 50:50 mixing CANNOT correct the PT, what could be wrong (2)? |
Something is inhibiting the extrinsic pathway
Factor VII inhibitor Lupus anti-coag |
|
|
You have an isolated, prolonged aPTT
If 50:50 mixing corrects the aPTT, what could be wrong? |
Factor Deficiency
(Factors XI, IX, VIII) NOTE: think about vWF if VIII is low NOTE: if there is NO bleed, think about Factor XII |
|
|
You have an isolated, prolonged aPTT
If 50:50 mixing CANNOT correct the aPTT, what could be wrong(3)? |
Something is inhibiting the intrinsic pathway
Factor inhibitor (VIII, IX, XI) Heparin Lupus anti-coag |
|
|
You have a prolonged PT AND aPTT
If mixing corrects neither, what could be the problem (2)? |
You have inhibition of the COMMON coag pathway
Factor V, X, II inhibitor Lupus anti-coag |
|
|
You have a prolonged PT AND aPTT
If mixing corrects both, what could be the problem? |
You have a deficiency of common pathway factors
(V, X, II) |
|
|
What is cryoprecipitate?
What does it contain? |
Precipitate of frozen plasma
vWF, Factors VIII, XIII Fibrinogen, Vitronectin, Fibronectin |
|
|
Hemophilia C is assoc. w/ what Factor deficiency?
|
Factor XI
|
