Hematology: Platelets and Bleeding Flashcards
Platelet plug is what stage of hemostasis
primary hemostasis
Fibrin clot is what stage of hemostasis
secondary hemostasis
If you have low platelet counts, which stage of hemostasis are you concerned about
primary
If you have a deficiency in a coagulation factor, which stage of hemostasis are you concerned about
secondary hemostasis
Primary hemostasis major sites of bleeding
Platelet dysfunction
mucocutaneous (mouth, nose, GI tract)
Secondary hemostasis major sites of bleeding
clotting factor deficiencies
Deep tissue (joints, muscles, soft tissue)
What are 4 simple steps to primary hemostasis
Adhesion (Platelet adheses to vWF)
Activation (Bind to vWF, platelet activates)
Aggregation (Platelets clump at site of injury)
Platelet plug formed
What values do the coagulation labs give
PT/INR (extrensic pathway)
PTT (Intrensic pathway)
PT & PTT prolonged= common pathway (Hepatic dysfunction, DIC)
Fibrinogen, D-Dimer
What are the vitamin K dependent factors
2, 7, 9, 10
Management of platelet or bleeding disorders
- Avoid contact sports (boxing, rugby, football, martial arts)
- Avoid OTC platelet inhibitors (Vitamin E, Garlic, Gingko)
- Control of menses
At which platelet count are you at an increased risk for spontaneous bleeding for platelet count
<20k
Only need around 50k to form a good clot
Platelet life span
8-10 days
What are the 4 etiologies of thrombocytopenia
- Decreased production of bone marrow
- Increased platelet distruction
- Abnormal platelet distribution
- Dilution of body fluids (Get saline)
What are some of the drugs that induce thrombocytopenia
Chemotherapy drugs, Sulfa/Vancomycin antibiotics, Anticoagulants (Heparin)
GERD medications
What is the most common cause of Isolated thrombocytopenia in children
ITP
Frequently follows 4-6 weeks after viral infection or live virus vaccine like MMR
If a kid gets the MMR vaxcine and then develops thrombocytopenia, what is most likely the cause
ITP- frequently follows 4-6 weeks after viral infection or live virus vaccine like MMR
If a patient has TMA, what is the correct discharge plan/ handoff? Where do you send them (i.e. home?)
*Admit to hospital- urgent- consult hematology. Urgent. Def not home.
What lab peripheral smear finding do you see in TMA
Schistocytes
Is there a negative or positive DAT/Coombs in TMA?
Negative- non-immune hemolysis
Deficiency of ADAMSTS13 is associated with what
TTP
The pentad of symptoms is associated with which bleeding disorder
TTP-
FAT RN- Fever, Anemia, Thrombocytopenia, Renal involvement, Neuro symptoms
VwF is not being cleaved, cause sheering of RBCs
Fever, Anemia, Thrombocytopenia, Renal involvement, Neuro symptoms are associated with which disease
TTP
TTP is accompanied by which symptoms
FAT RN- Fever, Anemia, Thrombocytopenia, Renal involvement, Neuro symptoms
VwF is not being cleaved, cause sheering of RBCs
TTP vs HUS symptom differences
Uremia (kidney injury) with HUS
Triad with HUS and Pentad with TTP
Triad: Thrombocytopenia, Anemia, renal dysfunction (uremia) (ATR, 3 middle symptoms)
Pentad:
FAT RN- Fever, Anemia, Thrombocytopenia, Renal involvement, Neuro symptoms
VwF is not being cleaved, cause sheering of RBCs
Shiga toxin predisposes you to which disorder
HUS
exposure to e.coli predisposes you to which disorder
HUS
Between HUS and TTP, which typically leads to AKI?
HUS has associated acute kidney injury
Burns, sepsis, trauma, and cancer therapy leads to what coagulation disorder
DIC- life threatening disorder- clotting and bleeding at same time
2 common drugs that result in acquired platelet dysfunction
Salicylates (asprin- irreversable inhibition of platelet cyclooxygenase)
NSAIDS(ibuprofen- reversible inhibition of cyclooxygenase)
