21 - Acquired Bleeding Disorders Flashcards
3 main causes of acquired bleeding disorders
DIC
liver failure
vit K deficiency
screening tests for the bleeding patient
CBC
PT / PTT / fibrinogen
PFA (platelet function analysis)
characteristics of bleeding disorder 2/2 liver disease
dec synth of all clotting factors except 8 and 13
dec clearance of fibrin degradation products or D-dimer
thrombocytopenia (2/2 congestive splenomegaly and dec TPO)
lab findings with thrombocytopenia due to liver disease
prolonged PT and PTT
F.VIII not decreased
fibrinogen synth often maintained until liver failure
tx for thrombocytopenia 2/2 liver dz
transfuse FFP
causes of DIC (and note top 3)
top 3 - infection (esp gram negs), malignancy (esp APL), obstetric complication
trauma, heat stroke, burns, extensive surgery
lab findings in DIC
PT prolonged and pos D-dimer are a must
PTT may be prolonged, normal, or even shortened
platelet count may be dec, but also may be normal or inc (acute phase reactant)
fibrinogen may be dec, but can be normal or inc as acute phase
may see schistocytes on PBS
what does D-dimer indicate?
both ongoing coag and fibrinolysis - hallmark of DIC
ddx of DIC
liver failure dilutional coagulopathy TTP HELLP syndrome extensive thrombosis
tx for DIC
treat underlying cause, supportive care
replacement therapy for bleeding (FFP, platelets)
heparin (only when thrombosis is dominant
antifibrinolytic agent (controversial)
vit K def causes what prothrombin precursor to be present in the blood?
PIVKA
vit K def lab findings
prolonged PT and PTT (PT will be prolonged first)
low factors 2, 7, 9, 10 and protein C, S
dx of vit K def
give vit K and see if PT corrects itself
which is the most common spontaneous factor specific inhibitor?
F.VIII inhibitor
mechanism for trauma causing bleeding disorder
causes hyperfibrinolysis > must be corrected by anti fibrinolytic agent
