Bleeding disorders Flashcards
4 steps in stopping bleeding
- promary hemostasis - platelets and VWF
- secondary - coagulation cascade
- generate thrombin
- form fibrin clot - clot stabilization
- factor 13 and thrombin activator - healing
what is center of cascade and rate limiting step
factor 10
what is common pathway
10+5> 2 (prothrombin (2) becomes thrombin (2a)> fibrinogen to fibrin (clot)
what is path of extrinsic
7+tissue factor to activate 10
what is intrinsic pathway
HMWK and prekallikrein>12>11>9+8>10
what are contact factors
- prekallikrein
- HMWK
- Factor 12
NOT needed to control bleeding
what are 2 tests and what do they test?
- protrombin time (INR) - extrinsic and common
2. activated partial thromboplastin time (PTT) - int and extrinsic
what is INR and what is is designed for
standardized PT
- measure for warfarin
2 general types of coagulation factors
- non-enzymatic types
- 5, 8, and TF - zymogens
- 2,7,9,10 - all K dependend
where are most factors made and 4 exeptions
liver
- tissue plasminoggen activator (tPA)
- VWF
- thrombomodulin
- 8 is made in liver but also endothelium
what is factor with shortest half life
7, then 5+8
where does coag occur
on membranes with expose phospholipids
- not resting cells
what is 1 inherited disorder of primary hemostasis
von willbrand disease
what is 2 inherited disorder of secondary hemostasis
- hemophilia
2. 11 def.
what is 3 acquired disorder of primary hemostasis
- drugs!
- thrombocytopenia
- uremia
what is 4 acquired disorder of secondary hemostasis
- DRUGs
- liver dis
- DIC
- vit K def
what is best predictor of bleeding disorder
bleeding Hx
what is VWF
- synthesized in endothelial cells
- platelet adhesion(to wall) and aggregation (to each other)
3 clinical components of VW disease
- bleeding
- fam Hx
- lab results
2 types of VW bleeds
- mucocutaneous
- menorhhagia
- epistaxis
- bruiding - musculoskeletal
what is familial pattern
autosomal inheritance
3 classes of VW disease
- mild/moderate quant. traits
- qualitative traits
- severe qual traits
4 lab findings in VW dis.
- normal CBC and PTT/INR
- low VWF antigen
- low VWF cofactor
- factor 8 activity decreased
treatments of VW dis.
medical - desmopressin - transfusions - OCP - topic agents gyne - hormonal IUD - endo ablation
2 types of x-linked hemophilia
B - factor 9
A - factor 8
Sx of hemophilia
- MSK bleeds
- mouth bleeds, epistaxis
- IC bleeds
- trauma bleeds
principle of bleed Mgmt
- treat first
- investigate later
4 categories of treatment
- specific replacement of factors
- topical agents to promote fibrin clot formation
- anti-fibrinolytic agents
- RICE
what is effect of liver disease
can get both bleeds and clots
5 effects of liver disease
- less synthesis - except 8
- abbreant synthesis
- decreased clearance
- accel. comsumption
- impaired fibrin formation
5 clues to liver based issues
- thrombocytopenia
- prolonged PT/INR
- decreased factors excepy 8
- fibrinogen assay
- DIC
3 treatments for liver disease
- treat liver disease
- vit K
- if major - desmopressin, anti-fibrinogen
what is DIC
- aquired syndrome of widespread coag
- overwhelms normal anti-thrombotic mechs
- may result in systemic bleeding or clots
patho of DIC
uncontrolled creation of thrombin and plasmin
> intravascular fibrin
> consumption of all hemostasis products
> activation of lysis
conditions assoc. with DIC
excessive TF release
- sepsis
- trauma
- CA
- obstetrical
- vascular
- immune
- toxins/drugs
test for DIC
none
- clinical + abnormal hemo screening
treat of DIC
treat underlying cause
what is vit K funciton
facilitates carbolxylation of 6 factors (10,9,7,2,C,S)
5 causes of vit K def.
- warfarin
- poor intake
- ABs
- biliary obstruction
- hemmoragic disease of newborn
3 lab findings in vit K def.
- long IRN
- long PTT
- low factos 10,9,7,2
what is DDx for long PTT but normal PT
- single factor def. (inheritied)
- VW disease
- inhibirots - aquired
- drug (hepain)
-
DDx for long PT, but normal PTT
inherited or aquired factor 7 def.
DDx for long PTT and PT
- inherited def. of common pathway
- inherited abnormal fobrinogen
- aquired
- inhibitors
- vit K def
- too much warfarin
- servere liver
- DIC
