Coagulopathies Flashcards
1
Q
Common Bleeding Disorders
A
1) Hemophilia
2) von Willebrand’s Disease (vWD)
3) Ideopathic Thrombocytopenia Purpura (ITP)
2
Q
Hemophilia Facts: Genetic/Ethnic
A
- Congenital bleeding disorders caused by deficiency or absence of clotting factors
- – Hemophilia A: Factor VIII
- – Hemophilia B: Factor IX
- X-linked: Inherited by male offspring from carrier mothers
- Female offspring of males w/hemophilia are “Obligatory carriers”
- No racial differences
3
Q
Hemophilia Facts: Severity
A
- Because factors VIII and IX are required for thrombin formation, hemophilia can cause prolonged, often spontaneous bleeding
- Mild: 5-40% of normal factor present; usually only bleed with significant trauma
- Moderate: 1-5% of normal factor present; Usually do not bleed spontaneously
- Severe: <1% of normal factor present; often have spontaneous bleeds
4
Q
Hemophilia: Diagnosis
A
- Factor assays; bleeding patterns; family history
- aPTT: prolonged in hemophilia (assess factors VIII and IX)
- Usually diagnosed within childhood
- – 95% by age 15
- – ~50% will have severe deficiency if there is reason to diagnose early in childhood
- Screen at birth, males with family Hx
5
Q
Hemophilia: Presentation
A
- Neonates: Intracranial hemorrhage; prolonged bleeding from circumcision
- Infants: Excessive bruising in soft tissues
- Older children and adults: spontaneous bleeding in joints
- – Hemarthrosis: ~70% of joint bleeds (knees, ankles, elbows most common)
- – Bleeds may also occur in CNS, GI tract, soft tissues and muscles
6
Q
Hemophilia: Long-term complications
A
- Hemarthropathy:
- – Bleeding into joints leads to an inflammatory process, causing permanent damage
- – Contractures
- – Nerve damage
7
Q
Hemophilia: Treatment (Non-pharmacologic)
A
- Focused of preventing or stopping bleeding episodes
- Hemarthrosis
- – RICE; Splinting, casts, crutches to allow joint or muscle rest after bleeding episode; Ice to slow down inflammatory process; PT once pain and inflammation resolve
8
Q
Hemophilia: Treatment (Pharmacologic)
A
- Desmopressin: Treats acute bleeding by increasing factor VIII
- Antifibrinolytics:
- – Tranexamic acid and aminocaproic acid
- – Treats acute bleeding by stabilizing fibrin clot
- – Useful in mucosal bleeds and dental procedures
9
Q
Hemophilia: Factor Replacement
A
- Treatment of of choice for acute bleeding episodes in severe hemophilia
- Dose depends on location and severity of bleeding
- Goal is to achieve hemostasis by adequately replacing factors
- – 40-60% of normal for joint and muscle bleeds
- – 80-100% of normal for iliopsoasmuscle, throat or neck, CNS, or GI bleeding
10
Q
Safety of Hemophilia Treatment
A
- 1980’s: Exposure to HIV and HCV through contaminated plasma-derived factors
- Now, virus reduction is used in factor collection, including nanofiltration, vapor heat, dry heat, pasteurization, solvent/detergent treatment
- Development of antibodies or inhibitors to factors
- – Does not promote bleeding, but makes subsequent bleeding episodes difficult to treat
11
Q
von Willebrand’s Disease Facts
A
- Autosomal dominant bleeding disorder
- Deficiency or dysfunction of von Willebrand factor (vWf)
- vWf has two roles:
1) Facilitates initial platelet plug at vascular injury
2) Carrier of factor VIII, preventing its degradation
12
Q
vWD: Subtypes
A
I) Levels of vWf are decreased 5-30%; most common subtype
II) Levels of vWf are normal, but dysfunctional
— Subtypes I and II are usually present with mild bleeding after procedures, mucosal bleeding, menorrhagia, and nose bleeds
III) Near or complete absence of vWf; bleeding similar to hemophilia and can be life threatening
13
Q
vWD: Labs
A
- Reduced plasma levels of vWf activity
- Reduced factor VIII activity
- Reduced vWf antigen levels
- Prolonged bleeding time
- ** NL levels do NOT exclude vWD
- ** PLT, PT, and PTT are all NL in vWD
14
Q
vWD: Acute treatment
A
- DDAVP: synthetic vasopressin that increases vWF and factor VIII (INEFFECTIVE in subtype III)
- If DDAVP fails:
- FFP
- Cryoprecipitate
- Concentrated factor VIII, fibrinogen, or fibronectin
- Subtype III: Concentrated factor VIII/vWF are available in larger institutions
15
Q
Ideopathic Thrombocytic Purpura (ITP): Facts
A
- Low platelet count that is not related to bone marrow suppression
- Common: Adults 66:1,000,000; Children 50:1,000,000
- Generally presents b/n 2-9yo and 20-50yo
16
Q
ITP: Children
A
- 2-3wk after viral illness
- Rapid drop in PLT
- Most resolve within 6mo
- Usually develops petechia and/or purpura
17
Q
ITP: Adults
A
- May have no prodromal illness
- Slow drop in PLT
- Tends to be chronic
18
Q
ITP: S/S
A
- Purpura (easy/excessive bruising)
- Petechiae (superficial bleeding)
- Prolonged bleeding from trauma
- Epistaxis
- Gum bleedings
- Hematuria, melena
- Menorrhagia
