Approach to bleeding Flashcards
Role of endothelium
Both mechanical and biological barrier
- separate platelet from prothrombotic -> stop it from activating
Platelet-type vs coagulation-type bleeding disorders
Platelet disorders
- site of bleeding: skin, mucous membranes
- petechiae present
- small, superficial bruises
- haemarthrosis/muscle bleeding -> very rare
- bleeding after cuts and scratches
- mild, immediate bleeding aft surgery/trauma
Coagulation factor disorders
- site of bleeding: deep soft tissues
- no petechiae
- large, deep bruises
- haemarthrosis/muscle bleeding -> common
- no bleeding after cuts/scratches
- delayed and sever bleeding after surgery/trauma
Main points to ask when taking bleeding history
Severity of disease
- life/limb threatening -> bleeding into enclosed spaces
- spontaneous/trauma
- local/systemic
- anemia/replacement
Congenital vs acquired
- onset, recurrent
- family hist
Presenting complaint
- severity
- age at presentation
- bleeding pattern and site
- prev blood test
Systems
- bi-panycytopenia, connective tissue, etc
Past medical hist
- haemostatic challenges -> surgery, dental, childbirth
- comorbidity
Family, drug and social hist
What to look out for during PE?
Hemodynamics
Inspection for bleeding
- petechiae
- bruising
- joint/hematoma
Cause of bleeding
- joint abnormalities
- organomegaly
- non-accidental injury
When should the pt undergo screening?
Abnormal bleeding history or signs of bleeding during PE -> bleeding disorder possible/likely
What are some first line tests for bleeding disorders?
Platelet count (FBC)
Peripheral film
Coagulation tests
- PT (extrinsic)
- aPTT (intrinsic)
- fibrinogen
What are some 2nd line tests for bleeding disorders?
Mixing test ***
Platelet fn test
Specific coagulation factor assays
Specialised tests
- factor inhibitors
How is APTT mixing test done and how are the results interpreted?
Pt plasma is mixed w/ normal plasma in 50-50 ratio
Interpretation of results:
- no correction -> bleeding due to inhibitor/lupus anticoagulant
- correction -> factor deficiency
What are some limitations of bleeding hist and investigations?
Mild bleeding symptoms doesn’t indicate bleeding disorder
- mild bleeding symptoms reported in healthy persons
- pediatric/young adults may not have had any hemostatic challenges
Normal tests does not mean no bleeding disorder
- rare bleeding disorders w/ normal PT and APTT (eg: factor 13 deficiency)
- PT and APTT -> fibrin detection only
What is a false +ve for thrombocytopenia?
Platelet clumping
- confirm genuine thrombocytopenia w/ PBF
How to approach coagulopathy (problem w/ APTT/PT)?
Prolonged APTT only
- intrinsic impaired
- possible causes -> congenital/acquired hemophilia, heparin, lupus anticoagulant
Prolonged PT only
- extrinsic impaired
- possible cause: factor 7 deficiency
Prolonged PT and APTT
- common impaired
- possible cause: warfarin use, DIC, liver disease
Decreased fibrinogen
- common impaired (specifically fibrinogen)
- possible causes: DIC, hypofibrinogenaemia, dysfibrinogenaemia
Increased fibrinogen
- common impaired (specifically fibrinogen)
- possible causes: acute phase reactant -> inflammation
When is there a need for urgent referral to hematology?
Severe (<30) and/or bleeding
Rapidly dropping
Bi/pan- cytopenia
Raised LDH +/- bilirubin
Abnormal PBF
Aetiology/associated conditions
- eg: DIC, malignancy
What kind of genetic disorder is Von Willebrand’s disease?
Autosomal dominant
- only need to inherit one copy to show symptoms
What kind of genetic disorder is hemophilia A?
X-linked recessive
