Lecture 7: Bleeding Disorders Flashcards
What two things in the history help determine bleeding disorder etiology?
- Bleeding site
- Underlying bleeding tendency that is enhanced by: other med conditions, intro of meds, or dietary supplements
why are age and sex important
severe inherited bleeding disorders often manifest in infancy or early childhood.
What does a mucocutaneous bleed suggest?
Qualitative/quantitative platelet disorder
What does a joint or soft tissue bleed suggest?
Coag factor disorder
What should an initial panel of lab tests include to help determine bleeding disorder etiology?
CBC
Peripheral blood smear
Coag panel (INR/PTT/PT)
CMP
Additional:
Bleeding time
PFA-100
What is a PFA for?
Whole blood flows through a capillary coated with platelet agonists.
platelets aggregate and stop the flow in the capillary
closure time is measured.
This assesses platelet function with greater sensitivity and reproducibility than the bleeding time.
What AC is measured with aPTT? Why?
UFH, because aPTT measures intrinsic pathway, which has thrombin.
What AC is measured with PT? Why?
Warfarin, because PT measures extrinsic pathway, which is more Vit-K dependent.
What other disease can PT monitor?
Liver, bc Vit K
What is INR?
International normalized ratio.
It is the ratio of PT to a standard sample.
What does high INR indicate?
Higher risk of bleeding.
What is the mnemonic for PTT and PT?
PTT = play table tennis (inside)
PT = play tennis (outside)
How are coag factors measured?
PT and aPTT can be compared in a sample plasma to a commercial plasma deficient in certain factors.
When do I use aPTT and PT tests together?
To monitor the transition between heparin and warfarin
What does a primary hemostasis disorder affect?
Mucous membrane bleeding, epistaxis, and petechiae.
Affects bleeding time and platelet counts.
What does a secondary hemostasis disorder affect?
Hemarthrosis, intracerebral hemorrhage, and deep tissue hematomas.
Affects PT and PTT.
What is hemophilia A?
Congenital deficiency of Factor 8. (vWF related)
What is hemophilia B?
Congenital deficiency of Factor 9
What kind of inheritance is hemophilia A?
X-linked recessive
1 in 5000 male live births
What kind of inheritance is hemophilia B? how many male live births
X-linked recessive
1 in 25000 male live births
How do female carriers of hemophilia present?
Asymptomatic.
How does severe hemophilia present commonly?
Early childhood spontaneous bleeds into joints or soft tissues.
How does mild hemophilia present commonly?
Excess bleeding post hemostatic challenge like surgery.
What is the secondary concern in patients with hemophilia?
They can develop inhibitors to the factors they are deficient in.
30% in A
5% in B
How does factor inhibition present in hemophiliacs?
Bleeding episodes resistant to factor 8 or 9 concentrate.
How do we diagnose hemophilia?
Low factor 8 or 9 ACTIVITY.
Prolonged aPTT
Note:
NORMAL PT/INR
NORMAL CBC
How much activity of the factors does hemostasis normally require?
At least 25%
What is considered mild factor 8 activity?
5-40%
How do I treat a minor bleed in a mild hemophilia A?
DDAVP (desmopressin)
How do I treat minor bleeds in a moderate-severe hemophilia A?
Factor 8 concentrate
How do I treat bleeds in hemophilia B?
Factor 9 concentrate
DDAVP DOES NOT WORK.
What is a common NSAID used to treat arthritis symptoms in hemophilia?
Celebrex only. COX-2 inhibitor
How often do hemophilia patients require factor concentrate infusions?
up to 3x a week
What other med is common for a hemophiliac to take besides celebrex?
Opioid analgesics often required for pain control.
What is the leading cause of death in hemophiliacs?
Transfusion-obtained HIV/AIDS
Hepatitis/Cirrhosis
What is the second leading cause of death in hemophiliacs?
ICH
It is also the most common cause of death dt hemorrhage.
What is the prognosis for a mild hemophiliac?
Normal life if they are treated prophylactically.
What are counseling tips for hemophiliacs?
AVOID CONTACT SPORTS
Monitor body for bruising/etc
Home infusion technique
Have a hematologist and hemophilia center you attend regularly.
What is the most common inherited bleeding disorder?
vW disease
What are the types of vWD?
Type 1 = Quantitative defect
Type 2 = Qualitative defect
Type 3 = Profound quantitative defect.
How is vWD inherited?
1 is autosomal dominant
2 is autosomal dominant primarily, recessive sometimes.
3 is autosomal recessive.
What is the most common type of vWD?
Type 1 (75% of cases)