hemostasis defect Flashcards
PT = ?
prothrombin time
APTT / PTT = ?
activated partial thromboplastin time
TT = ?
Thrombin Time
BT = ?
bleeding time
PFA-100 = ?
Platelet function analyzer
PT measures?
1, 2, 5, 7, 10 (extrinisic)
PT uses _____ to start the rxn
Thromboplastin
INR = ?
international normalized ratio
PT used to monitor ___?
Warfarin therapy
APTT measures procaogulant activity of the ____ pathway, most sensitive to ____?
entire; higher number (8, 9, 10) NOT effected by 7
Prolonged PTT can mean ______ or ____
anticoagulant drugs/split products or defect in 8, 9, 10
Thrombin Time measures procoagulant activity of ___, sensitive to ____
Fibrinogen, anticoagulant effect of heparin/fibrin split products
BT measures what?
platelet/vessel interaction, number/fcn of plt - NO OTHER FACTOR AFFECTS THIS
PFA100 measures
in vitro bleeding time - plt response to agonists
Which tests are sensitive to heparin?
PTT/APTT, TT
Hemophilia A/B are factors ___/___?
8,9
Hemophilia is a ____ disorder
Xlinked
Hemophilia will have prolonged _____ ; Classifed by on ________
PTT; residual percentage of factor activity - relative to normal population
Classification cutoff for severe, moderate, mild
1, 2-5, 10
Severe Hemophilia will present with (without treatment)
spontaenous hemorrhaging to joints, muscles, soft tissues, retroperitoneal space, CNS; severe arthritis/join destruction
Moderate Hemophilia will present with:
Bleeding given trauma
Mild Hemophilia will present with:
bleed with trauma (ie. Surgery) - tho typ diagnosed after bad event
Treat hemophilia with:
recombinant/purified factor products
Carrier females with bleeding are ______
symptomatic carriers
Factor XI Deficiency is a ____ disease common in ______ (population)
AR; Ashkenazi Jews
Factor XI Def. Presentation ________; test show prolonged ____?
Post operative hemorrhage; PTT
Factor VII def labs shows ____
Only PT is prolonged; PTT is normal
von Willebrand disease tests:
Bleeding time, vWF antigen, vWF activity, Factor 8 activity, Multimeric analysis, RIPA (ristocetin induced platelet aggregation)
RIPA used to diagnose which type of vWD?
Type 2 b - abnormal clearance by platelet
Type 1 vWD = ?
partial quantitative deficiency
Type 2 vWD = ?
Quality deficiency
type 2b vWD = ?
abnormal clearance (vWF) by plt
Type 3 vWD = ?
severe/total quantitative deficiency
acquired factor 8 inhibitor because makes _______ - typically concurrent with
antibody against factor - autoimmune illness, post partum, old
Acquired factor VIII inhibitor shows abnormal ___
abnormal PTT - remains prolonged even after mixing
Mixing test refers to
mixing normal plasma with pt plasma - PTT corrected?
Causes of prolonged PTT:
Heparin in sample Hemophilia A/B Factor XI def Factor XII def* Acquired hemophilia vWD lupus anticoagulant*
PT»_space; PTT
Liver disease, vit K deficiency, Warfarin/rat poison
PTT»PT
DIC - disseminated intravascular coagulation
Live disease affects clotting because most factors are synthesized in the _____, especially affects _____?
liver
V and vit K (2, 7, 9 10 - CS)
Liver disease labs will show:
Severely prolonged PT; prolonged PTT
Low fibrinogen, TT prolonged, decreased plt count
Vit K deficiency is typically caused by:
No oral intake - diet or gut flora taken out via antibiotics
Warfarin/rat poison
Vit K deficiency will show:
prolonged PT> PTT
DIC can be caused by:
massive trauma, hemorrhagic, septic shock, aminontic fluid embolism, burns, acute leukemia, transfusion, drug reaction
What happens in DIC?
COagulation cascade activated (Fibrin/plt microthrombi + plug capillary - tissue infarction
Hemorrhage - factors/plt consumed
DIC lab results
Low platelet, very low fibrinogen, PTT> PT; D dimer
Hypercoagulable state risk factors - people who have thrombosis for:
- No apparent reason
- Recurrent/early age/unexpected
- Life threatening/unusual sites
- family history
Hypercoagulable state exist when:
chronic damage vessel, excess procoagulant factor, deficiency of anticoagulant factors/fibrinolytic activity
Lupus anticoagulant is a ____ disorder
Hypercoagulable state/disorder = thormbotic syndrome
APS
antiphospholipid antibody syndrome APS
Lupus anticoagulant lab:
Prolonged PTT
MIxing - no correction. long PTT
dRVVT = long clotting time
Extra phospholipid - correct the time
Lupus anticoagulant lab reasoning
antibody to platelet membranes/phospholipids so reaction cannot start
dRVVT = ? and what does it do?
dilute Russell’s Viper Venom Test = directly activates factor X
Familial hypercoaguable state/thrombophilia: 4 most common ones:
Antithrombin
Protein C
Protein S
Resistance to protein C (Factor V Leiden)
Virchow’s triad includes:
- Decreased blood flow (venous stasis)
- INflammation of/near blood vessel (altered vessles)
- Intrinsic alteration of blood - altered coagulability
Arterial vs Venous thrombi
A: mostly aggregated platelets - “white”
V: large amount of fibrin + RBC - “red”
Diagnosis of venous thrombosis
D-Dimer assay
Ultrasound doppler
Spiral CT/Ventilation/perfusion (PE)
Ventilation/perfusion - what two types of imagine done?
gaseous radionuclide inhaled - areated
Radionuclide injected - circulating blood in lungs
Look for mismatched
D-Dimer result suggests:
negative: no PE/DVT
Positive: Hm…
Treatment of venous thrombosis
inhibit coagulation - heparin (unfractionated/LMWH - 5 days) + Warfarin
Treatment of arterial thrombosis
Heparin + fibrinolytic agent (tPA) + antiplatelet agents (aspirin, Ticlid, clopidogrel, Reopro)
Asprin does _____
inhibit COX1 irreversibly
Ticlid is a
thienopyridines
Plavix/Clopidogrel works as
ADP receptor antagonists
Reopro/Abciximab works by
GPIIb/IIIa inhibitor
Factor V Leiden
APC resistant - hypercoagluable
AD
Prothrombin G20210A
AD - elevated prothrombin in Cp
Protein C deficiency
Cannot inactivate Va/VIIIa - hypercoagulable state
Vit K deficiency = exacerbate problem
Prophylaxis for surgery
Warfarin induced skin necrosis
Protein S deficiency
AD - hypercoagulable
Warfarin induced skin necrosis, neonatal purpura fulminans
Antithrombin deficiency
AD (Homo = fatal)
Heparin resistant
Cannot inactivate thrombin, Xa, IXa, XIa, and XIIa
Hyperhomocyteinemia
causes injury to endothelial cell lining = increase risk of thrombosis
Increase factor 8 = ?
hypercoagluable
Impaired fibrinolysis (plasminogen/tPA def) leads to
risk thrombosis
