quizzes 3 review Flashcards
. Plasminogen is activated to plasmin by all of the following except:
Calcium
TPA - Tissue Plasminogen Activator
Kallekrein
Urokinase
Streptokinase
Calcium
Which factor of the contact system, if deficient, may lead to a bleeding disorder? 1.HMWK
2. Prekallikrein
3. Factor XII
4. Factor XI
5. None of the above
- Factor XI
A patient with a known Factor IX deficiency can expect:
A prolonged APTT
clinical bleeding problems
a normal platelet count
This anticoagulant drug is a Vitamin K antagonist:
Coumadin
Protein C helps to control coagulation by:
Inactivating factors Va and VIIIa
All of the following are decreased in Von Willebrand’s disease except:
VIII:c
VIII:VWF Antigen
IX
VWF:Rco
IX
Which of the following should be considered if a patient has a prolonged APTT?
Patient may being treated with heparin
Hypofibrinogenemia and/or DIC
Patient Hct of 68%
Which of the following is/are true concerning FSP?
They are cleared by the reticuloendothelial system If present in large amounts, they may inhibit fibrin formation
They are formed by the action of plasmin on fibrin(ogen)
The reptilase time is a test that can be used to differentiate the presence of ____________ from a
fibrinogen abnormality
heparin
The factor deficient plasma used in a factor assay:
contains less than 1% of the factor being tested contains normal amounts of all factors except the one being tested
is added to the patient plasma before the PT or APTT is done
Factor XII can be activated by
contact with negatively charged surfaces kallekrein
collagen
When doing correction studies on a patient with a lupus inhibitor, what can be expected?
no correction with normal plasma, correction with saline, correction with reagent platelets
The anticoagulant and blood ratio used for routine coagulation testing:
sodium citrate; 1 part anticoagulant to 9 parts blood
Factor V Leiden is:
a genetic mutation of factor V a deficiency of factor V
A prolonged PT can result from all of the following EXCEPT:
Vitamin K deficiency
Liver disease
Presence of circulating anticoagulants (inhibitors) hypofibrinogenemia
Von Willebrand’s disease
Von Willebrand’s disease
Both the PT and APTT are sensitive to deficiencies of Factor:
II
Which of the following are consistent with a prolonged thrombin time?
Factor I deficiency
A PIVKA test is used primarily to diagnose:
Vitamin K deficiency
Which of the following present with an increased APTT and a clinical picture of thrombosis?
patient with lupus anticoagulant
true or false: If a patient has a severe Factor XIII deficiency, the following tests will be normal:
PT
APTT
TT
FSP
true
Which of the following tests will be abnormal for a patient with severe hemophilia B who has
developed a factor IX inhibitor:
APTT
Which of the following correction studies will be corrected for a patient with severe Factor V
deficiency:
PT 1:1 with normal plasma at 0 hours
Normal synthesis of Vitamin K dependent factors is impaired in:
liver disease
extremely poor diet
coumadin therapy
malabsorption
non-supplemented parenteral nutrition
The secondary phase of platelet aggregation is______ and induced by____from the platelet
granules.
irreversible; ADP
An inducer of platelet aggregation that is released from the platelet dense granules is:
adenosine diphosphate (ADP)
The ___________is a thin coating of proteins and mucopolysaccharides on the endothelial cells in the
vessels.
glycocalyx
Aspirin interferes with platelet function by:
inhibiting cyclooxygenase
Which of the following regulate vasoconstriction?
1. glycocalyx
2. thromboxane A2
3. serotonin
4. ADP
- thromboxane A2
- serotonin
Fibronectin is produced in the ______________ and has a role in________________.
endothelial cells; binding cells to one another
Heparan sulfate and thrombomodulin serve to:
inhibit fibrin formation
Which are the most numerous of the platelet granules?
Alpha granules
Which of the following are contained in the dense granules?
1. ADP
2. ATP
3. Calcium
4. Serotonin
- ADP
- ATP
- Calcium
- Serotonin
Which of the following causes vasodilation?
prostacylin or PGI2
In the platelet membrane, which of the following serves as the receptor for VonWillebrand factor?
Glycoprotein Ib
Which of the following are roles of thromboxane A2?
stimulation of granule secretion and vasoconstriction
Which of the following factors is exclusive to the extrinsic pathway of coagulation?
IV
VIII
IX
VII
XII
VII
Which platelet membrane system stores intracellular calcium without connecting to the platelet
surface?
dense tubular system
Which of the following statements are true regarding VonWillebrand’s factor?
1. it is found in the endothelium
2. it is found in the platelet
3. it is part of the circulating factor VIII molecule
4. it provides energy for platelet aggregation
- it is found in the endothelium
- it is found in the platelet
- it is part of the circulating factor VIII molecule
true or false:
Primary platelet aggregation is
reversible
true
true or false
Secondary platelet aggregation is
reversible
false
true or false
Platelet adhesion and aggregation
requires the presence of calcium ions
false
true or false
Coagulation proteins are produced in
the liver and the endothelium
true
true or false
Factors I,II,V,VIII are the Vitamin K
dependent factors
false
true or false
Factors XI, XII, PK, HMWK are the
contact factors
true
true or false
Vitamin K acts to carboxylate certain
coagulation factors
true
The APTT will be abnormally prolonged with:
deficiency of factor VIII
The most common bleeding tendency of platelet defects is/are:
mucocutaneous bleeding
Both the PT and APTT are sensitive to deficiencies of
Factor II
The patient has a normal platelet count. Platelet aggregation studies show normal aggregation with
ristocetin, but abnormal aggregation with all other aggregating agents. The bleeding time and clot
retraction were abnormal. What disorder is suspected?
Glanzman’s thrombasthenia
Which of the following may cause an increased bleeding time?
aspirin ingestion
Von Willebrands disease Vessel defect
platelet function defect
aspirin ingestion
Von Willebrands disease Vessel defect
platelet function defect
Stabilization of the fibrin clot requires adequate amounts of:
Factor XIII
Following receipt of a specimen in the lab, there is an 8 hour delay before the PT can be done. The
results would most likely be:
prolonged due to the loss of factor V
The thrombin time evaluates which reaction(s) in the coagulation cascade?
fibrinogen to fibrin
The proper anticoagulant to blood ratio for routine coagulation testing is:
1:9
The following factors are consumed during in vitro clotting:
I,II,V,VIII,XIII
Plasma is diluted in a fibrinogen assay to decrease the:
influence of inhibitors
Normal value for PT is approximately:
12-15 sec
A patient has the following results: history of mucocutaneous bleeding; PT=11 sec; APTT=30 sec;
prothrombin consumption test=33 sec; thrombin time=11 sec. What is a likely cause of this patient’s
coagulation difficulties?
thrombocytopenia
Functions of activated factor XII include:
initiation of clotting cascade
positive feedback to PK to kallekrein reaction activation of factor XI activation of plasminogen activation of factor XI and initiation of clotting cascade
The activated partial thromboplastin reagent in the APTT:
provides maximum contact activation
Hemostatic disorders involving vessel or vascular supporting tissue abnormalities include:
hereditary hemorrhagic telangectasia and senile purpura
Substances that have anti-plasmin activity include:
alpha 2 macroglobulin and alpha 2 antiplasmin
A patient who has a hct >60% should have the anticoagulant adjusted in the blue top tube because:
excess anticoagulant will neutralize reagents
Platelet adhesion means platelets sticking to___________; aggregation means platelets sticking
to____________.
the vessel; each other
Primary hemostasis is defined as:
formation of platelet plug
Factor I
fibrinogen
Factor V
labile factor
Factor X
Stuart-Prower factor
Factor XII
Hageman factor
The difference between ITP and TTP is/are:
TTP is characterized by thrombosis and ITP is characterized by immune destruction of platelets
Which of the following aggregating agents normally have a biphasic curve?
ADP and epinephrine
Vascular abnormalities that cause bleeding problems are often:
a diagnosis of exclusion
Effects of aspirin on platelet function include(s)
inhibition of cyclooxygenase abnormal aggregation prolongation of the bleeding time