Question 1

Which of the following tests can be used to monitor Coumadin therapy?

Accepted Answer

A)  PT-INR 
B)  Factor assays 
C)  APTT 
D)  Reptilase time 
A)  PT-INR 
B)  Factor assays 
C)  APTT 
D)  Reptilase time

Question 2

A patient is screened positive for APCR. What does this mean?

Accepted Answer

A)  The patient is at risk for hemorrhage. 
B)  The patient has a high probability of factor VLeiden mutation. 
C)  The patient is on warfarin. 
D)  The patient is on heparin. 
A)  The patient is at risk for hemorrhage. 
B)  The patient has a high probability of factor VLeiden mutation. 
C)  The patient is on warfarin. 
D)  The patient is on heparin.

Question 3

Explain the effects of the following on coagulation testing:
a. Clotted sample
b. Ratio of blood to anticoagulant 55%
d. >1-hour difference between specimen collection and analysis

Accepted Answer

a. Clotted sample: Because factors are c

Question 4

Laboratory testing for von Willebrand factor contains variables that can result in difficulty in diagnosing the disease. Which of the following factors is identified as a variable that can contribute to this difficulty?

Accepted Answer

A)  Abnormal screening results 
B)  Difficulty in obtaining the specimen 
C)  Age of patient 
D)  Standardization of the reference plasma 
A)  Abnormal screening results 
B)  Difficulty in obtaining the specimen 
C)  Age of patient 
D)  Standardization of the reference plasma

Question 5

Normal pooled plasma is used as the diluent in a mixing study because it:

Accepted Answer

A)  Minimizes SERPIN activity 
B)  Contains 100% of all the factors needed to achieve a clot 
C)  Minimizes the effects of sodium citrate on the sample 
D)  Neutralizes any residual platelets left in the sample after centrifugation 
A)  Minimizes SERPIN activity 
B)  Contains 100% of all the factors needed to achieve a clot 
C)  Minimizes the effects of sodium citrate on the sample 
D)  Neutralizes any residual platelets left in the sample after centrifugation

Question 6

A patient's laboratory coagulation test results in an immediate correction of the PT and aPTT after mixing studies and no correction after performing the PT and aPTT after a 2-hour incubation at 37°C. What is the possible deficiency or inhibitor?

Accepted Answer

A)  Factor deficiency 
B)  Lupuslike anticoagulant 
C)  F-VIII inhibitor 
D)  F-V loss 
A)  Factor deficiency 
B)  Lupuslike anticoagulant 
C)  F-VIII inhibitor 
D)  F-V loss

Question 7

List the tests that are commonly utilized in the workup of the following:
a. von Willebrand's disease
b. Hemophilia A
c. Factor VIII inhibitor
d. Bernard-Soulier syndrome
e. TTP

Accepted Answer

a. von Willebrand's disease: PT, APTT, B

Question 8

Which of the following instruments uses both electromechanical and optical density as a means of clot detection?

Accepted Answer

A)  STArt 4 Coagulation system 
B)  BBL Fibrosystem 
C)  Trinity Biotech Coag-A-Mate XM 
D)  AMAX Destiny Plus 
A)  STArt 4 Coagulation system 
B)  BBL Fibrosystem 
C)  Trinity Biotech Coag-A-Mate XM 
D)  AMAX Destiny Plus

Question 9

What preanalytical quality control procedures are necessary when performing platelet aggregation studies?

Accepted Answer

A)  Assess patient medications before obtaining specimen 
B)  Obtain specimen after a 12-hour fast 
C)  Perform a bleeding time before testing 
D)  Collect the specimen in a glass tube 
A)  Assess patient medications before obtaining specimen 
B)  Obtain specimen after a 12-hour fast 
C)  Perform a bleeding time before testing 
D)  Collect the specimen in a glass tube

Question 10

The international normalized ratio (INR) is used to standardize the wide variations in the reagent of prothrombin testing. What is the target goal of the ISI value in commercial reagents?

Accepted Answer

A)  Reduce the lot-to-lot variability 
B)  Correlate one manufacturer with another 
C)  Obtain a reagent that has an ISI of 1.0 or close to it 
D)  Reduce the use of anticoagulant therapy 
A)  Reduce the lot-to-lot variability 
B)  Correlate one manufacturer with another 
C)  Obtain a reagent that has an ISI of 1.0 or close to it 
D)  Reduce the use of anticoagulant therapy

Exam 36: Hemostasis: Laboratory Testing and Instrumentation

Which of the following tests can be used to monitor Coumadin therapy?

A patient is screened positive for APCR. What does this mean?

Explain the effects of the following on coagulation testing: a. Clotted sample b. Ratio of blood to anticoagulant < 9:1 c. Patient hematocrit >55% d. >1-hour difference between specimen collection and analysis

Laboratory testing for von Willebrand factor contains variables that can result in difficulty in diagnosing the disease. Which of the following factors is identified as a variable that can contribute to this difficulty?

Normal pooled plasma is used as the diluent in a mixing study because it:

A patient's laboratory coagulation test results in an immediate correction of the PT and aPTT after mixing studies and no correction after performing the PT and aPTT after a 2-hour incubation at 37°C. What is the possible deficiency or inhibitor?

List the tests that are commonly utilized in the workup of the following: a. von Willebrand's disease b. Hemophilia A c. Factor VIII inhibitor d. Bernard-Soulier syndrome e. TTP

Which of the following instruments uses both electromechanical and optical density as a means of clot detection?

What preanalytical quality control procedures are necessary when performing platelet aggregation studies?

The international normalized ratio (INR) is used to standardize the wide variations in the reagent of prothrombin testing. What is the target goal of the ISI value in commercial reagents?

Introduction

Cellular Homeostasis

Structure and Function of Hematopoietic Organs

Hematopoiesis

The Erythrocyte

Hemoglobin

Granulocytes and Monocytes

Lymphocytes

The Platelet

The Complete Blood Count and Peripheral Blood Smear Evaluation

Introduction to Anemia

Anemias of Disordered Iron Metabolism and Heme Synthesis

Hemoglobinopathies: Qualitative Defects

Thalassemia

Megaloblastic and Nonmegaloblastic Macrocytic Anemias

Hypoproliferative Anemias

Hemolytic Anemia: Membrane Defects

Hemolytic Anemia: Enzyme Deficiencies

Hemolytic Anemia: Immune Anemias

Hemolytic Anemia: Nonimmune Defects

Nonmalignant Disorders of Leukocytes: Granulocytes and Monocytes

Nonmalignant Lymphocyte Disorders

Introduction to Hematopoietic Neoplasms

Myeloproliferative Neoplasms

Myelodysplastic Syndromes

Acute Myeloid Leukemias

Precursor Lymphoid Neoplasms

Mature Lymphoid Neoplasms

Hematopoietic Stem Cell Transplantation

Morphologic Analysis of Body Fluids in the Hematology

Primary Hemostasis

Secondary Hemostasis and Fibrinolysis

Disorders of Primary Hemostasis

Disorders of Secondary Hemostasis

Thrombophilia

Hematology Procedures

Bone Marrow Examination

Automation in Hematology

Flow Cytometry

Chromosome Analysis of Hematopoietic and Lymphoid Disorders

Molecular Analysis of Hematologic Diseases

Quality Assessment in the Hematology Laboratory

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