Hemostasis Exam 3 Flashcards by christine Michael

The manual differential showed the presence of nucleated RBC’s and blasts. Which instrument flagged for the possible presence of blasts?

a. ADVIA
b. CELL-DYN
c. Coulter
d. Sysmex

a. ADVIA

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Which instrument did not alert the operator to the possibility of nucleated RBCs?

a. ADVIA
b. CELL-DYN
c. Coulter
d. Sysmex

c. Coulter

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What do you suspect is the cause of the variation in platelet flagging?

a. Some instruments have higher levels of sensitivy
b. All instruments use the same principle for counting platelets.
c. Some instruments are susceptible to false-positive platelet flagging under certain conditions
d. Some instruments have higher values for the lower limit of the reference range.

c. Some instruments are susceptible to false-positive platelet flagging under certain conditions

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A patient film demonstrates agglutinated RBCs and the CBC shows an elevated MCHC. What other parameters will be affected by the agglutination of the RBCs?

a. MCV will be decreased and the RBC count will be increased
b. MCV will be decreased and the RBC count will be decreased
c. MCV will be increased and the RBC count will be decreased
d. MCV will be decreased and the RBC count will be increased

c. MCV will be increased and the RBC count will be decreased

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Low-voltage DC is used to measure:

a. cell nuclear volume
b. total cell volume
c. cellular complexity in the nucleus
d. cellular complexity in the cytoplasm

b. total cell volume

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Orthogonal light scatter is used to measure:

a. cell volume or size
b. internal complexity of the cell
c. cellular granularity
d. nuclear density

b. internal complexity of the cell

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On the Coulter instruments, hematocrit is a calculated value. Which of the following directly measured parameters is used in the calculation of this value?

a. RDW
b. Hemoglobin
c. MCV
d. MCHC

c. MCV

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What is the most common acquired bleeding disorder?

a. ACOTS
b. Vitamin K deficiency
c. Liver disease
d. VWD

a. ACOTS

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Which is a typical form of anatomic bleeding?

a. Epistaxis
b. Menorrhagia
c. Hematemesis
d. soft tissue bleed

d. soft tissue bleed

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To a deficiency of which factor is the PT most sensitive?

a. Prothrombin
b. VII
c. VIII
d. IX

b. VII

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Which of the following conditions causes a prolonged thrombin time?

a. Prothrombin deficiency
b. Antithrombin deficiency
c. Hypofibrinogenemia
d. Warfarin therapy

c. Hypofibrinogenemia

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In what type of VWD is the RIPA test result positive when ristocetin is used at a concentration of less than 0.5mgmL?

a. Subtype 2A
b. Subtype 2B
c. Subtype 2N
d. Type 3

b. Subtype 2B

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What is the typical treatment for vitamin K deficiency when the patient is bleeding?

a. Vitamin K and FP
b. Vitamin K and platelet concentrate
c. Vitamin K and factor VIII concentrate
d. Vitamin K and prothrombin complex concentrate

a. Vitamin K and FP

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If a patient has anatomic soft tissue bleeding and poor wound healing, but the PT, PTT, thrombin time, platelet count, and platelet functional assay results are normal, a deficiency of what factor could exist?

a. Fibrinogen
b. Prothrombin
c. Factor XII
d. Factor XIII

d. Factor XIII

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What therapy may be used for a hemophilic boy who is bleeding and who has a high titer of factor VIII inhibitor?

a. FP
b. Cryoprecipitate
c. Factor VIII concentrate
d. Recombinant activated coagulation factor VII

d. Recombinant activated coagulation factor VII

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What is the most prevalent form of VWD?

a. Type 1
b. Type 2A
c. Type 2B
d. Type 3

a. Type 1

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Which of the following assays can be used to distinguish vitamin K deficiency from liver disease?

a. Factor V assay
b. PT
c. Factor VII assay
d. Protein C assay

a. Factor V assay

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Mucocutaneous hemorrhage is typical of:

a. acquired hemorrhagic disorders
b. Localized hemorrhagic disorders
c. Defects in primary hemostasis
d. Defects in fibrinolysis

c. Defects in primary hemostasis

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What is the prevalence of venous thrombosis in the United States?

a. 0.001
b. 0.01
c. 10% to 15%
d. 500,000 cases per year

a. 0.001

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What is thrombophilia?

a. Predisposition to thrombosis secondary to a congenital or acquired disorder
b. Inappropriate triggering of the plasma coagulation system
c. A condition in which clots form uncontrollably system
d. Inadequate fibrinolysis

a. Predisposition to thrombosis secondary to a congenital or acquired disorder

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What acquired thrombosis risk factor is assessed in the hemostasis laboratory?

a. smoking
b. Immobilization
c. Body mass index
d. LA

d. LA

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Trousseau syndrome, a low grade chronic DIC, is often associated with what type of disorder?

a. Renal disease
b. Hepatic disease
c. Adenocarcinoma
d. Chronic inflammation

c. Adencarcinoma

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What is the most common heritable thrombosis risk factor in whites?

a. Prothrombin G20210A mutation
b. APC resistance
c. Antithrombin deficiency
d. Protein S deficiency

b. APC resistance

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In most LA profiles, what test is generally the first used to screen for LA?

a. DRVVT
b. Low-phospholipid PTT
c. KCT
d. PT

a or b

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A patient with venous thrombosis is tested for protein S deficiency. The protein S activity, antigen and free antigen are all less than 65% and the C4bBP level is normal. What type of deficiency is likely? a. Type I b. Type II c. Type III d. No deficiency is indicated, because the reference range includes 25%

a. Type I

An elevated level of what fibrinolytic system assay is associated with arterial thrombotic risk? a. PA1-1 b. Lipoprotein (a) c. Factor VIIa d. Factor XII

a. PA1-1

How does lipoprotein (A) cause thrombosis? a. It causes elevated factor VIII levels b. It coats the endothelial lining of arteries c. It contributes additional phospholipid in vivo for formation of the Xase complex d. It substitutes for plasminogen or TPA in the forming clot

d. It substitutes for plasminogen or TPA in the forming clot

What test may be used to confirm the presence of LA? a. Bethesda titer b. PT c. Antinuclear antibody d. PTT using high-phospholipid reagent

d. PTT using high-phospholipid reagent

What deoxyribonucleic acid (DNA)-based test may be used to confirm APC resistance? a. Prothrombin G20210A b. FVL c. MTHFR 1298 d. MTHFR 677

b. FVL

What theraputic agent may occasionally cause DIC? a. Factor VIII b. Factor VIIa c. Antithrombin concentrate d. Activated prothrombin complex concentrate

d. Activated prothrombin complex concentrate

Name an old fibrinolysis assay that has been largely replaced by the quantitative D-dimer assay a. Euglobulin lysis b. Soluble fibrin monomer c. 5-M urea solubility assay d. Fibrinogen degradation process

d. Fibrinogen degradation process

What is the most important application of the quantitative D-dimer test? a. diagnose primary fibrinolysis b. diagnose liver and renal disease c. Rule out deep venous thrombosis d. Diagnose acute myocardial infarction

C. Rule out deep venous thrombosis

The autosomal dominant disorder associated with decreased platelet production is: a. Fanconi anemia b. TAR syndrome c. May-Hegglin anomaly d. Wiskott-Aldrich anomaly

b. TAR syndrome

Which of the following is not a hallmark of ITP? a. Petechiae b. Thrombocytopenia c. Large overactive platelets d. Megakaryocyte hypoplasia

d. Megakaryocyte hypoplasia

The specific antigen most commonly responsible for the development of NAIT is: a. Bak b. HPA-1a c. GP 1b d. Lewis antigen a

b. HPA-1a

A 2-year old child with an unexpected platelet count of 15,000/mcL and a recent history of a viral infection most likely has: a. HIT b. NAIT c. acute ITP d. chronic ITP

c. acute ITP

What is the first step in the treatment of HIT? a. Start low-molecular-weight heparin therapy b. Stop heparin infusion immediately c. switch to warfarin (coumadin) immediately d. Initiate a platelet transfusion

b. Stop heparin infusion

A defect in primary hemostasis (platelet response to an injury) often results in: a. musculoskeletal bleeding b. mucosal bleeding c. hemarthroses d. none of the above

b. mucosal bleeding

When a drug acts as a hapten to induce thrombocytopenia, an antibody forms against which of the following? a. typically unexposed, new platelet antigens b. the combination of the drug and the platelet membrane protein to which it is bound c. the drug alone in the plasma, but the immune complex then binds to the platelet membrane d. the drug alone, but only when it is bound to the platelet membrane

b. the combination of the drug and the platelet membrane protein to which it is bound

TAR refers to: a. abnormal platelet morphology in which the radial striations of the platelets are missing b. abnormal appearance of the iris of the eye in which radial striations are absent c. abnormal bone formation, including hypoplasia of the forearms d. Neurologic defects affecting of the root (radix) of the spinal nerves

c. abnormal bone formation, including hypoplasia of the forearms

Neonatal autoimmune thrombocytopenia occurs when: a. the mother lacks a platelet antigen that the infant possesses, and she builds antibodies to that antigen, which cross the placenta b. The infant develops an autoimmune process such as ITP secondary to in utero infection c. The infant develops an autoimmune disease such as lupus erythematosus before birth d. The mother has an autoimmune antibody to her own platelets, which crosses the placenta and reacts with the infant's platelets

d. the mother has an autoimmune antibody to her own platelets, which crosses the placenta and reacts with the infant's platelets

HUS in children is associated with: a. diarrhea caused by Shigella speciaes b. Meningitis caused by Haemophilus species c. Pneumonia caused by Mycoplasma species d. Pneumonia caused by respiratory viruses

a. Diarrhea caused by Shigella species

The clinical presentation of platelet-related bleeding may include all of the following except: a. bruising b. nosebleeds c. gastrointestinal bleeding d. bleeding into the joints (hemarthroses)

d. bleeding into the joints (hemarthroses)

A defect in GP IIb/IIIa causes: a. Glanzmann thrombasthenia b. BSS c. Gray platelet syndrome d. Storage pool disease

a. Glanzmann thrombasthenia

Aspirin ingestion blocks the synthesis of: a. Thromboxane A2 b. Ionized calcium c. Collagen d. ADP

a. Thromboxane A2

Patients with BSS have which of the following laboratory test findings? a. abnormal platelet response to arachidonic acid b. abnormal platelet response to ristocetin c. abnormal platelet response to collage d. Thrombocytosis

b. abnormal platelet response to ristocetin

Which of the following is the most common of the hereditary platelet function defects? a. glanzmann thrombasthenia b. BSS c. Storage pool defects d. Multiple myeloma

c. storage pool defects

A mechanism of antiplatelet drugs targeting GP IIb/IIIa function is: a. interference with platelet adhesion to the subendothelium by blocking of the collagen binding site b. inhibition of transcription of the GP IIb/IIIa gene c. direct binding to GP IIb/IIIa d. Interference with platelet secretion

c. direct binding to GP IIb/IIIa

The impaired platelet function in MPNs results from: a. abnormally shaped platelets b. extended platelet life span c. increased procoagulant activity d. decreased numbers of a and b granules

d. decreased numbers of a and b granules

Which is a congenital qualitative platelet disorder? a. Senile purpura b. Ehlers-Danlos syndrome c. Henoch-Schonlein purpura d. Waldenstrom macroglobulinemia

b. Ehlers-Danlos syndrom

In uremia, platelet function is impaired by higher than normal levels of: a. Urea b. Uric acid c. Creatinine d. NO

d. NO

The platelet defect associated with increased paraprotiens is: a. impaired membrane activation owning to protein coating b. Hypercoagulability owing to antibody binding and membrane activation c. impaired aggregation because the hyperviscous plasma prevents platelet endothelium interaction d. hypercoagulability because the increased proteins bring platelets closer together, which lead to inappropriate aggregation

a. impaired membrane activation owning to protein coating

What happens if a coagulation specimen collection tube is underfilled? a. the specimen clots and is useless b. the specimen is hemolyzed and is useless c. clot-based test results are falsely prolonged d. chromogenic test results are falsely decreased

c. clot-based test results are falsely prolonged

If you collect blood into a series of tubes, when in the sequence should the hemostasis (blue stopper) tube be filled? a. after a lavender-topped or green-topped tube b. first, or after a nonadditive tube c. after a serum separator tube d. last

b. first, or after a nonadditive tube

What is the effect of hemolysis on a hemostasis specimen? a. in vitro platelet and coagulation activation occur b. the specimen is icteric or lipemic c. hemolysis has no effect d. the specimen is clotted

a. in vitro platelet and coagulation activation occur

Most coagulation testing must be performed on PPP, which is plasma with a platelet count then: a. 1000/mcL b. 10,000/mcL c. 100,000/mcL d. 1,000,000/mcL

b. 10,000/mcL

You wish to obtain a 5ml specimen of whole blood/anticoagulant mixture. The patient's hematocrit is 65%. What volume of anticoagulant should you use? a. 0.32 ml b. 0.5 ml c. 0.64 ml d. 0.68 ml

a. 0.32 ml

You perform whole-blood lumiaggregometry on a specimen from a patient who complains of easy bruising. Aggregation and secretion are diminished when the agonists thrombin, ADP, arachidonic acid and collagen are used. What is the most likely platelet abnormality? a. storage pool disorder b. aspirin like syndrom c. ADP receptor anomaly d. glanzmann thrombasthenia

a. storage pool disorder

What is the 'gold standard' assay for HIT? a. enzyme immunoassay b. SRA c. platelet lumiaggregometry d. washed platelet aggregation

b. SRA

What agonist is used in platelet aggregometry to detect VWD? a. Arachidonic acid b. Ristocetin c. Collagen d. ADP

b. Ristocetin

Deficiency of which single factor is likely when the PT result is prolonged and the PTT result is normal? a. Factor V b. Factor VII c. Factor VIII d. Prothrombin

b. Factor VII

A prolonged PT, a low factor VII level, but a normal factor V level are characteristic of an acquired coagulopathy associated with which of the following? a. Hemophilia b. Liver disease c. Thrombocytopenia d. Vitamin K deficiency

d. Vitamin K deficiency

The patient has deep vein thrombosis. The PTT is prolonged and is not corrected in an immediate mix of patient plasma with an equal part of normal plasma. What is the presumed condition? a. Factor VIII inhibitor b. LA c. Factor VIII deficiency d. Factor V Leiden mutation

b. LA

You perform a 5-mol/L urea solubility assay on a specimen from a patient with chronic bleeding and prolonged wound healing. The clot dissolves within 2 hours. What is the presumed cause? a. abnormally increased fibrinolysis b. Factor XIII deficiency c. Factor IX deficiency d. the clot dissolution is normal

b. Factor XIII deficiency

What is the PT INR therapeutic range for warfarin therapy when a patient has a mechanical heart failure? a. 1 to 2 b. 2 to 3 c. 2.5 to 3.5 d. Warfarin is not indicated for patients with mechanical heart valves

c. 2.5 to 3.5

Monitoring of a patient taking warfarin showed that her anticoagulation results remained stable over a period of about 7 months. The frequency of her visits to the laboratory began to decrease, so the period between testing averaged 6 weeks. This new testing interval is: a. acceptable for a patient with stable anticoagulation results after 6 months. b. Unnecessary because monitoring for patients taking oral anticoagulants can be discontinued entirely after 4 months of stable test results c. too long even for a patient with previously stable test results; 4 weeks is the standard

c. Too long even for a patient with previously stable test results; 4 weeks is the standard

What is the greatest advantage of point of care testing? a. it permits self-dosing of warfarin b. it is expensive c. it is convenient d. it is precise

c. it is convenient

You collect a citrated whole-blood specimen to monitor UFH therapy. What is the longest it may stand before the plasma must be separated from the cells? a. 1 hour b. 4 hours c. 24 hours d. indefinitely

a. 1 hour

What test is used to monitor high dose UFH therapy in the cardiac catherization operating suite? a. PT b. PTT c. Bleeding time d. ACT

d. ACT

Which test is used most often to monitor UFH therapy in the central laboratory? a. PT b. PTT c. ACT d. Chromogenic anti-fever Xa heparin assay

b. PTT

What test is used most often to monitor LMWH therapy in the central laboratory? a. PT b. PTT c. ACT d. Chromogenic anti-fever Xa heparin assay

c. chromogenic anti-fever Xa heparin assay

What is an advantage of LMWH therapy over UFH therapy? a. it is cheaper b. it causes less bleeding c. it has a stable dose response d. there is no risk of HIT

c. it has a stable dose response

In what situation is a DTI used? a. DVT b. HIT c. Any situation in which warfarin could be used d. Uncomplicated AMI

b. HIT

What laboratory test may be used to monitor DTI therapy when PTT results are unreliable? a. PT b. ECT C. Reptilase clotting time d. Chromogenic anti-fever Xa heparin assay

b. ECT

What is the reference method for detecting aspirin or clopidogrel resistance? a. platelet aggregometry b. aspirin works c. verifyNOW d. PFA-100

b. platelet aggregometry

What is the name of the measurable platelet activation metabolite used in the AspirinWorks assay to monitor aspirin resistance? a. 11-dehydrothromboxane B2 b. Arachidonic acid c. Thromboxane A2 d. Cyclooxygenase

a. 11-dehydrothromboxane B2

Which of the following is an intravenous antiplatelet drug used in the cardiac catheterization laboratory? a. abciximab b. Ticlopidine c. Prasugrel d. Clopidogrel

a. abciximab

Which of the following is a newly developing oral anticoagulant? a. argatroban b. lepirudin c. bivalirudin d. rivaroxaban

d. rivaroxaban

Which of the following is not a point of care instrument for the measurement of PT? a. coagucheck xs pt b. gem pcl plus c. cascade poc d. multiplate

d. multiplate

The photo-optical method of end-point detection can be described as: a. measurement of a color producing chromophore at a wavelength of 405 nm b. measurement of the change in OD of a test solution as a result of fibrin formation c. application of an electromagnetic field to the test cuvette to detect the decreased motion of an iron ball within the cuvette d. measurement of the turbidity of a test solution resulting from the formation of antigen-antibody complexes using latex particles

b. measurement of the change in OD of a test solution as a result of fibrin formation

Modern coagulation analyzers have greatly enhanced the ability to perform coagulation testing as a result of which of the following? a. maintenance of a level of accuracy and precision similar to that of manual methods b. increase in reagent volume capabilities to improve sensitivity c. automatic adjustment of results for interfering substances d. improved flagging capabilities to identify problems in sample quality or instrument function

d. improved flagging capabilities to identify problems in sample quality or instrument function

Which of the following is considered to be an advantage of the mechanical end-point detection methodology? a. it is not affected by lipemia in the test sample b. it has the ability to provide a graph of clot formation c. It can incorporate multiple wavelengths into a single testing sequence d. it can measure proteins that do not have fibrin formation as the end point

a. it is not affected by lipemia in the test sample

which of the following methods use the principle of changes in light scatter or transmission to detect the end point in the reaction? a. immunologic, mechanical, photo-optical b. photo-optical, nephelometric, mechanical c. photo-optical, nephelometric, immunologic d. chromogenic, immunologic, mechanical

c. photo-optical, nephelometric, immunologic

Which of the following is a feature of semiautomated coagulation testing analyzers? a. the temperature is maintained externally by a heat block or water bath b. reagents and samples usually are added manually by the operator c. timers are automatically started as soon as the analyzer adds reagents to the test cuvette. d. the end point must be detected by the operator

b. reagents and samples usually are added manually by the operator

When a sample has been flagged as being icteric by an automated coagulation analyzer, which method would be most susceptible to erroneous results because of the interferring substance? a. mechanical clot detection b. immunologic antigen-antibody reaction detection c. photo-optical clot detection d. chromogenic end-point detection

c. photo-optical clot detection

Platelet function testing has been incorporated into the routine coagulation laboratory in recent years as a result of: a. increased use of drugs that stimulate platelet b. the convenience of being able to do the testing on the same instrument that performs the coagulation testing c. increased therapeutic use of aspirin in the treatment of heart disease d. increased outpatient/outreach testing that prevents the laboratory from having access to patients to do bleeding time tests

c. increased therapeutic use of aspirin in the treatment of heart disease

All of the following are performance characteristics to consider in the selection of a coagulation analyzer except: a. location of the manufacturer's home office b. instrument footprint c. ease of use for the operator d. variety of tests the instrument can perform

a. location of the manufacturer's home office

The PFA-100 measures platelet function by: a. detecting the change in blood flow pressure along a small tube when a clot impairs blood flow b. detecting the aggregation of latex beads coated with platelet activators c. graphing the transmittance of light through platelet rich plasma over time after addition of platelet activators d. detecting the time it takes for a clot to form as blood flows through a small aperture in a tube coated with platelet activators

d. detecting the time it takes for a clot to form as blood flows through a small aperture in a tube coated with platelet activators

Point of care coagulation testing is used mainly: a. to monitor patients receiving oral anticoagulant therapy b. to monitor patients taking platelet inhibitors such as aspirin c. to provide a baseline for all subsequent patient test result comparisons when the patient starts any kind of anticoagulant therapy d. to monitor obstetric patients at risk of fetal loss

a. to monitor patients receiving oral anticoagulant therapy