Coagulopathy Cases Flashcards
2 areas of focus for a PE in a patient with a suspected bleeding disorder
Evidence of recent bleeding
Evidence of a systemic disease which may have secondary bleeding complications
Platelet type bleeding (what is it, 2 indications)
The physical findings suggest a platelet problem as the cause for the patient’s bleeding
2 indications: petechiae and mucosal surface bleeding
Factor type bleeding
Suggested by hemarthroses and deep tissue hematomas
3 tests that form part of a coagulation screening panel
PT/INR
PTT
CBC with a PBS
What will the lab results look like for someone with a non-hematological bleeding?
Normal INR, PTT, and platelet count
Is PTT or PT intrinsic or extrinsic?
PTT: intrinsic
PT/INR: extrinsic
vW Disease
In the category of factor deficiency (vWF)
VWF is a carrier protein for factor 8
If severely deficient, can lead to a prolonged PTT via associated factor 8 deficiency
Factor inhibitors
Can be medications, specific factor inhibitors, or non specific factor inhibitors
Mixing studies
Determines whether a prolonged PTT is due to a factor deficiency or inhibitor
Mix patient’s plasma with a control plasma
If deficient, the PTT will be corrected
If there is an inhibitor, the PTT will remain long
Only can be interpreted with confidence when the PTT is significantly prolonged
vWD clinical and lab presentation
Platelet-type bleeding (mucosal bleeding)
Normal or mildly prolonged PTT
Mild vWD is one of the causes of hematologic bleeding with a normal PTT, INR and CBC!
Why is an inherited deficiency of factor 12 unlikely?
12 deficiency is not associated with bleeding
Do platelte abnormalities cause INR and PTT abnormalities
NO
The coagulation cascade is completely separate from platelet activity in vitro
Coagulopathy
Increased tendency to bleed, impaired hemostasis, or bleeding disorder
Thrombophilia
Predisposition to clotting
Are single deficiencies of factors in the common pathway common?
Nope!
If PT and PTT are both abnormal, more likely to be multiple factor deficiencies
How does liver disease contribute to reduced factor production
Liver synthesizes most of the coagulation factors
Liver probs = multiple deficiencies = INR and PTT prolonged
Vitamin K is required for the synthesis of what factors?
10, 9, 7, 2
How does vitamin K deficiency contribute to reduced factor production
Needed for the synthesis of 4 factros
Vit K deficiency = prolongation of INR and PTT (INR more so)
How to determine between factor deficiencies from liver disease and vitamin K deficiencies
Give vitamin K
If vitamin K is the problem, the factor levels, INR and PTT will normalize within 1-2 days
No effect if liver synthesis is the problem
Specific factor inhibitors
Antibodies with activity against a specific clotting factor
Non specific factor inhibitors
The inhibitor is not specific against a certain factor - broadly inhibits the formation of a clot
AKA lupus anticoagulant
How can medications be factor inhibitors
Anticoag meds can prolog the PTT and prevent correction of the pTT when mixed with normal plasma
Ex: DOACs
May also prolong INRO
Don’t do a mixing study if they are on these drugs!
Lupus anticoagulant
Anti-phospholipid antibody
Autoantibodies that tend to lead to a thrombotic tendency, NOT a bleeding tendency
It is an in VITRO anticoagulant phenomenon, not in VIVO
Add extra phospholipid to PTT test and it will normalize
If you see a patient with a prolonged PTT who is NOT bleeding and has no history, what do you think of?
It may well be due to a lupus anticoagulant
