Hemostasis Testing Flashcards
How does the presence of FDPs inhibit clotting in coagulation testing?
Interfere with
fibrin polymerization
A patient is given an excess of urokinase. What would you expect of the PT and APTT
results and why?
both increased because plasmin breaks down fibrinogen
What test will determine total fibrinogen levels (including dysfunctional)?
immunological fibrinogen
How do you differentiate HIT from HITTS?
HIT - PLT 100,000 1-3 days after heparin
HITTS - PLT low 20,000 1-3 days after heparin (thrombosis)
What does INR stand for and what is its purpose?
internationalized ratio: std patient PT results between labs
How does the Reptilase Time differ from the Thrombin Time?
RT cleaves fibrinopeptides A/B and is not inhibited by thrombin inhibitors such as heparin
Which of the platelet agonists should result in a longer lag phase and a single phase
aggregometry graph in 100% of normal subjects after the agent is added to PRP
Collagen
Which test is mostly used to monitor the effects of heparin
APTT or anti Xa activity
What are PIVKAS and which screening test is most sensitive to their presence?
produced when pt is on an anticoag, PT is most sensitive to screen, ISI value based on sensitivity to pIVKAS
If a factor XIII deficiency is suspected, what test should be performed and what is the
expected result in a deficiency
urea clot lysis - clot will lyse <24hr
A patient has a normal APTT and a prolonged PT. A 50:50 mix was done and the PT was
repeated. The PT result was now within the normal reference range. What is the most
likely cause of the original abnormal result
VII deficiency
TT tests for adequacy of
fibrinogen
whuch procedure will test the common pathway?
RVVT
What test is used to evaluate the body’s fibrinolytic ability
euglobulin clot lysis
Which phospholipid dependent routine screening test is affected most by the presence
of a lupus inhibitor?
APTT