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Flashcards in Plts Deck (17):
1

6 aspects of platelet function testing

adhesion tests,
aggregation tests,
assessment of the granular content,
assessment of the release reaction,
investigation of the prostaglandin pathways
tests of platelet coagulant activity.

2

Tests based on platelet aggregation

Light transmission
Impedance transmission
Impedance pot aggregation
Lumiaggregometry

3

Tests based on platelet adhesion under shear

PFA
Global thrombosis test

4

Cons pfa

Rigid closed system
Platelet count – HCT-dependent
Not sensitive to platelet secretion defects.

5

Cons impact cone analyzer

Expensive
Experienced staff
Lack of clinical studies
Not widely available

6

Cons global thrombosis time

Lack of clinical studies
Not widely available

7

Cons TEG

Limited HCT and platelet count range (for platelet system)
Lack of clinical studies

8

PRo's pfa

In vitro standardized BT
Easy, quick POCT
Sensitive to severe platelet defects

9

Pro lta

Historical gold standard
Diagnostic method
Flexible
Different platelet pathways investigated
Sensitive to anti-plt therapy

10

Pro of rotem plts

POCT
Predicts bleeding
Reduces blood transfusions
Improves clinical outcome
Global hemostasis test
WB platelet aggregometry

11

What must be present for normal RIPA

Fxnal vwf
Gp 1b/9/5 receptor

12

How to confirm do BSS

Flow showing absence GP1 absence of ristocetinnresponse

13

What is defect in BSS

Absence of gp1b/IX/v receptor- which binds to vwf

14

Glanzsmans

GPIIb/IIIa (ITG αIIbβ3), either qualitative or quantitative, which results in faulty platelet aggregation and diminished clot retraction. 

15

Light transmission aggregometry

Centrifuged platelet-rich plasma samples are monitored before and after the addition of an agonist (ADP, collagen, epinephrine, arachidonic acid, ristocetin, thrombin receptor activating peptide, and thromboxane A2 mimetic), assessing shape change, lag phase, percent of aggregation, slope of aggregation, and deaggregation

16

Plt agg resukt for gt

Failure to aggregate with all agonists except ristocetin

17

Dx glanzsmans

Can have normal cbe
Normal risto
Prolonged pfa
Reduced cd41 and cd 61 on flow with normal cd 42
Genomic DNA sequencing of the 45 exons comprising the αIIbβ3 unit, along with the splice sites of the ITGB3 and ITGA2B gene, should be investigated, and the established mutations should be confirmed with a second DNA sample analysis.