Bleeding disorders- part 1 Flashcards
What does a mucocutaneous bleed indicate? Is this considered primary or secondary?
likely qualitative/quantitative platelet defects
primary hemostasis
What does a joint/soft tissue bleed indicate? Is this considered primary or secondary?
Likely disorders of coagulation factors
What lab test should you order for a bleeding pt?
CBC
Blood smear
Coag panel
CMP
What modern test is used to calculate the bleeding time?
Platelet function analyzer (PFA-100)
What does a prolonged PTT indicate?
deficiencies of Factors VIII or IX –hemophilia
What test would you order if you want to monitor heparin?
Heparin = monitor with aPTT = Intrinsic pathway
PTT detects deficiencies of the ____ pathway
intrinsic
What does PTT stand for?
Partial thromboplastin time (PTT, aPTT)
What does PT stand for ? It measures the ____ pathway
Prothrombin Time
Extrinsic pathway
When evaluating the PT, Add ______ - reacts with ____ to initiate clotting through extrinsic/common pathway
thromboplastin (TF)
VIIa
Would order ____ when monitoring Warfarin. It is ____ dependent
PT
Vit K dependent, think extrinsic pathway
Which clotting factor has the shortest half life?
Factor VII
** What does an increased INR indicate?
higher risk of a bleed
** What does an decreased INR indicate?
higher risk of developing a clot
Defect in the extrinsic pathway causes an (increase/decrease) of ____
increase in PT
Defect in the intrinsic pathway causes an (increase/decrease) of ____
increase in aPTT
What will a defect in the common pathway cause?
increase in both PT and aPTT
**How do disorders of primary hemostasis present? What do they affect?
mucous membrane bleeding, epistaxis, and petechiae.
bleeding time and platelet count.
**How do disorders of secondary hemostasis present? What do they affect?
hemarthrosis, intracerebral hemorrhage, and deep tissue hematomas.
affect PT and PTT
**What things will a mixed bleeding disorder affect?
bleeding time and platelet count, as well as PT and PTT
When would you need to order both a PT and aPTT?
transitions between heparin and warfarin therapy
assessing pts with s/s of hemorrhage or thrombosis (or about to have a medical procedure)
Hemophilia A: congenital deficiency of coagulation _____
Hemophilia B: congenital deficiency of coagulation ____
factor VIII
factor IX
What is a hallmark s/s of hemophilia?
bleeding into a joint, usually the knee
** What is the frequency of hemophilia A? How is it inherited?
1 per 5000 live male births
Most common X-linked genetic disease
** What is the frequency of hemophilia B? How is it inherited?
1 in 25,000 live male births
X-linked recessive, leading to affected males and carrier females.
What percentage of hem A patient develop antibodies to the clotting factors? Hem B?
Approximately 30% of patients with hemophilia A
< 5% of patients with hemophilia B
What lab findings would be expected in a hemophilia pt?
Low factor VIII/IX
aPTT is prolonged
PT/INR and CBC is normal
Normal hemostasis requires at least ____ of factor VIII activity
25%
** mild hem A presents with a minor bleed, what is the treatment? Major bleed?
minor: DDAVP
major: DDAVP or factor VIII concentrate
** mod/severe hem A presents with a minor bleed, what is the treatment? Major bleed?
Minor: Factor VIII concentrate
Major: Factor VIII concentrate
** mild/mod/severe hem B presents with a minor bleed, what is the treatment? Major bleed?
minor: Factor IX concentrate
major: factor IX concentrate
What is the normal treatment regimen for a severe hem pt?
require infusions of factor concentrate up to 3 times a week to prevent recurrent joint bleeding
Hem pt with arthritis symptoms, prescribe _____. Why?
celecoxib (Celebrex), works on COX2
NSAIDs and aspirin should be avoided due to the increased risk of bleeding from inhibition of platelet function
What is the most important life-threatening complication for a hem pt?
Intracranial hemorrhage and hemorrhages into the soft tissue
What is the MC cause of death in hem pts?
due to transfusion-obtained HIV/AIDS and hepatitis/cirrhosis
_____ is the most common inherited bleeding disorder
Von Willebrand Disease
vWF is a large multimeric glycoprotein that binds to its receptor,______, bridging platelets together and tethering them to the site of vascular injury.
platelet glycoprotein Ib
**Type 1 vWD is a ____ defect. How is it inherited? What is the clinical manifestation?
quantitative (not enough vWF)
autosomal dominant
zero to severe bleeding
**Type 2 vWD is a ____ defect. How is it inherited? What is the clinical manifestation?
Qualitative defect (dysfunctional vWF)
Commonly autosomal dominant (sometimes autosomal recessive)
moderate to severe bleeding
**Type 3 vWD is a ____ defect. How is it inherited? What is the clinical manifestation?
quantitive defect (almost zero or zero vWF)
autosomal recessive
severe bleeding