Question 1

Which of the following is an acceptable sample for a prothrombin time (PT)test?

Accepted Answer

A) one that was collected 22 hours before testing and stored at room temperature 
B) one with a very small clot that was easily removed 
C) 3.2% sodium citrate blood sample immediately collected following a serum separator tube 
D) blood anticoagulated with heparin and brought to the laboratory within 1 hour 
A) one that was collected 22 hours before testing and stored at room temperature 
B) one with a very small clot that was easily removed 
C) 3.2% sodium citrate blood sample immediately collected following a serum separator tube 
D) blood anticoagulated with heparin and brought to the laboratory within 1 hour A

Question 2

A patient admitted to the hospital with thrombosis is given the standard heparin dosage.Twenty-four hours after the heparin is started,the PTT is 38 seconds (reference range,25 to 37 seconds).Both normal and abnormal controls are within their limits.Which of the following is most likely?

Accepted Answer

A) laboratory error 
B) patient has low antithrombin 
C) heparin-induced thrombocytopenia 
D) patient should be switched to low-molecular-weight heparin (LMWH) 
A) laboratory error 
B) patient has low antithrombin 
C) heparin-induced thrombocytopenia 
D) patient should be switched to low-molecular-weight heparin (LMWH) B

Question 3

Which of the following practices is necessary when collecting blood specimen from a heparin or saline lock?

Accepted Answer

A) Flush the IV line with 5mL saline before collecting the specimen. 
B) The first 5mL of blood that is collected must be immediately inserted into the blood tube for testing. 
C) Flush the IV line with heparin before collecting the specimen. 
D) Collect the blood directly into an evacuated tube. 
A) Flush the IV line with 5mL saline before collecting the specimen. 
B) The first 5mL of blood that is collected must be immediately inserted into the blood tube for testing. 
C) Flush the IV line with heparin before collecting the specimen. 
D) Collect the blood directly into an evacuated tube. A

Question 4

A patient's platelet count drops 4 days after being placed on heparin.Select the correct interpretation.

Accepted Answer

A) The patient has heparin-induced thrombocytopenia. 
B) The patient has benign, limited thrombocytopenia related to heparin. 
C) A bleeding time should be performed to evaluate qualitative platelet disorders. 
D) An immunoassay for heparin-dependent anti-platelet factor 4 (PF4) should be performed to distinguish heparin-induced thrombocytopenia from benign, limited thrombocytopenia related to heparin. 
A) The patient has heparin-induced thrombocytopenia. 
B) The patient has benign, limited thrombocytopenia related to heparin. 
C) A bleeding time should be performed to evaluate qualitative platelet disorders. 
D) An immunoassay for heparin-dependent anti-platelet factor 4 (PF4) should be performed to distinguish heparin-induced thrombocytopenia from benign, limited thrombocytopenia related to heparin.

Question 5

A patient has a factor VIII level of 50% activity.Which is most likely true regarding what can be expected for this patient's clinical situation?

Accepted Answer

A) severe bleeding 
B) moderate bleeding 
C) mild bleeding 
D) normal with respect to factor VIII 
A) severe bleeding 
B) moderate bleeding 
C) mild bleeding 
D) normal with respect to factor VIII

Question 6

A patient sample has normal platelet aggregation patterns for all agonists except that no reaction occurs with ristocetin.Ristocetin agglutination is not corrected with exogenous VWF.What condition is most likely?

Accepted Answer

A) VWD 
B) storage pool disorder 
C) Bernard-Soulier syndrome 
D) aspirin use 
A) VWD 
B) storage pool disorder 
C) Bernard-Soulier syndrome 
D) aspirin use

Question 7

What is the test commonly used to monitor the high heparin doses used in cardiac bypass surgery?

Accepted Answer

A) PTT 
B) prothrombin time 
C) thrombin clotting time 
D) fibrinogen 
A) PTT 
B) prothrombin time 
C) thrombin clotting time 
D) fibrinogen

Question 8

Which of the following is an acceptable sample for testing on a photo-optical clot-detecting instrument?

Accepted Answer

A) lipemic plasma 
B) hemolyzed plasma 
C) serum 
D) plasma collected using a 9:1 ratio of whole blood to 3.2% sodium citrate 
A) lipemic plasma 
B) hemolyzed plasma 
C) serum 
D) plasma collected using a 9:1 ratio of whole blood to 3.2% sodium citrate

Question 9

Which of the following is necessary for normal platelet aggregation?

Accepted Answer

A) ristocetin 
B) von Willebrand factor (VWF) 
C) epinephrine 
D) fibrinogen 
A) ristocetin 
B) von Willebrand factor (VWF) 
C) epinephrine 
D) fibrinogen

Question 10

How often must controls be run for the PT and PTT?

Accepted Answer

A) with each patient sample 
B) at least once per 8-hour shift 
C) at least once per 24 hours 
D) with each batch of 10 
A) with each patient sample 
B) at least once per 8-hour shift 
C) at least once per 24 hours 
D) with each batch of 10

Question 11

Which of the following conditions would have a normal PTT?

Accepted Answer

A) lupus anticoagulant 
B) fibrinogen of 50 mg/dL 
C) factor VII deficiency 
D) heparin therapy 
A) lupus anticoagulant 
B) fibrinogen of 50 mg/dL 
C) factor VII deficiency 
D) heparin therapy

Question 12

A patient is positive for fibrin degradation products and negative for D dimers.Which condition is most likely?

Accepted Answer

A) systemic fibrinolysis 
B) DIC 
C) hypofibrinogenemia 
D) deep vein thrombosis (DVT) 
A) systemic fibrinolysis 
B) DIC 
C) hypofibrinogenemia 
D) deep vein thrombosis (DVT)

Question 13

The urea solubility test evaluates factor

Accepted Answer

A) I. 
B) V. 
C) X. 
D) XIII. 
A) I. 
B) V. 
C) X. 
D) XIII.

Question 14

A patient has an elevated thrombin time and normal reptilase time.Which of the following situations is most likely?

Accepted Answer

A) heparin therapy 
B) low fibrinogen 
C) elevated fibrin split products 
D) dysfibrinogenemia 
A) heparin therapy 
B) low fibrinogen 
C) elevated fibrin split products 
D) dysfibrinogenemia

Question 15

Which of the following is good practice in regard to phlebotomy on patients with hemostasis testing ordered?

Accepted Answer

A) Make sure the patient is fasting. 
B) Always draw the sodium citrate tube last. 
C) Collect the blood in a glass syringe. 
D) Use a 20- or 21-gauge needle. 
A) Make sure the patient is fasting. 
B) Always draw the sodium citrate tube last. 
C) Collect the blood in a glass syringe. 
D) Use a 20- or 21-gauge needle.

Question 16

A patient is stabilized on warfarin with an international normalized ratio (INR)of 2.7.He develops pneumonia and is admitted to the hospital.His appetite is depressed and he is placed on broad-spectrum antibiotic agents.At 1 week after the admission,his INR is 5.0.What is the most likely interpretation?

Accepted Answer

A) The patient should be given more warfarin. 
B) A PTT should be performed to rule out heparin administration. 
C) A new sample should be collected to rule out a clotted specimen. 
D) Vitamin K is reduced, increasing the effects of warfarin. 
A) The patient should be given more warfarin. 
B) A PTT should be performed to rule out heparin administration. 
C) A new sample should be collected to rule out a clotted specimen. 
D) Vitamin K is reduced, increasing the effects of warfarin.

Question 17

Patients with which of the following would have a normal PT?

Accepted Answer

A) liver disease 
B) disseminated intravascular coagulation (DI
C)  
C) factor VII deficiency 
D) factor IX deficiency 
A) liver disease 
B) disseminated intravascular coagulation (DI
C)  
C) factor VII deficiency 
D) factor IX deficiency

Question 18

A platelet aggregation study shows diminished response to all agonists except for a small response to arachidonic acid and full response to ristocetin.Which condition is most likely?

Accepted Answer

A) Glanzmann thrombasthenia 
B) aspirin use 
C) VWD 
D) platelet release defect 
A) Glanzmann thrombasthenia 
B) aspirin use 
C) VWD 
D) platelet release defect

Question 19

The platelet function assay (PFA-100)will be normal and is no value to perform in patients who have

Accepted Answer

A) a qualitative platelet disorder. 
B) von Willebrand disease (VW
D) . 
C) Glanzmann thrombasthenia. 
D) factor VIII deficiency. 
A) a qualitative platelet disorder. 
B) von Willebrand disease (VW
D) . 
C) Glanzmann thrombasthenia. 
D) factor VIII deficiency.

Question 20

A prolonged PTT is corrected when mixed with normal plasma and tested immediately and after a 2-hour incubation.Which test (or tests)should be performed next?

Accepted Answer

A) Bethesda titer 
B) high-phospholipid PTT 
C) anti-Xa assay 
D) factor VIII and IX assays 
A) Bethesda titer 
B) high-phospholipid PTT 
C) anti-Xa assay 
D) factor VIII and IX assays

Exam 42: Laboratory Evaluation of Hemostasis

Which of the following is an acceptable sample for a prothrombin time (PT)test?

A patient admitted to the hospital with thrombosis is given the standard heparin dosage.Twenty-four hours after the heparin is started,the PTT is 38 seconds (reference range,25 to 37 seconds).Both normal and abnormal controls are within their limits.Which of the following is most likely?

Which of the following practices is necessary when collecting blood specimen from a heparin or saline lock?

A patient's platelet count drops 4 days after being placed on heparin.Select the correct interpretation.

A patient has a factor VIII level of 50% activity.Which is most likely true regarding what can be expected for this patient's clinical situation?

A patient sample has normal platelet aggregation patterns for all agonists except that no reaction occurs with ristocetin.Ristocetin agglutination is not corrected with exogenous VWF.What condition is most likely?

What is the test commonly used to monitor the high heparin doses used in cardiac bypass surgery?

Which of the following is an acceptable sample for testing on a photo-optical clot-detecting instrument?

Which of the following is necessary for normal platelet aggregation?

How often must controls be run for the PT and PTT?

Which of the following conditions would have a normal PTT?

A patient is positive for fibrin degradation products and negative for D dimers.Which condition is most likely?

The urea solubility test evaluates factor

A patient has an elevated thrombin time and normal reptilase time.Which of the following situations is most likely?

Which of the following is good practice in regard to phlebotomy on patients with hemostasis testing ordered?

Patients with which of the following would have a normal PT?

A platelet aggregation study shows diminished response to all agonists except for a small response to arachidonic acid and full response to ristocetin.Which condition is most likely?

The platelet function assay (PFA-100)will be normal and is no value to perform in patients who have

A prolonged PTT is corrected when mixed with normal plasma and tested immediately and after a 2-hour incubation.Which test (or tests)should be performed next?

An Overview of Clinical Laboratory Hematology

Safety in the Hematology Laboratory

Blood Specimen Collection

Care and Use of the Microscope

Quality Assurance in Hematology and Hemostasis Testing

Cellular Structure and Function

Hematopoiesis

Erythrocyte Production and Destruction

Erythrocyte Metabolism and Membrane Structure and Function

Hemoglobin Metabolism

Iron Kinetics and Laboratory Assessment

Leukocyte Development, Kinetics, and Functions

Platelet Production, Structure, and Function

Manual, Semiautomated and Point-of-Care Testing in Hematology

Automated Blood Cell Analysis

Examination of the Peripheral Blood Film and Correlation with the Complete Blood Count

Bone Marrow Examination

Body Fluid Analysis in the Hematology Laboratory

Anemias: Red Blood Cell Morphology and Approach to Diagnosis

Disorders of Iron Kinetics and Heme Metabolism

Anemias Caused by Defects of DNA Metabolism

Bone Marrow Failure

Introduction to Increased Destruction of Erythrocytes

Intrinsic Defects Leading to Increased Erythrocyte Destruction

Extrinsic Defects Leading to Increased Erythrocyte Destruction Nonimmune Causes

Extrinsic Defects Leading to Increased Erythrocyte Destruction Immune Causes

Hemoglobinopathies (Structural Defects in Hemoglobin)

Thalassemias

Nonmalignant Leukocyte Disorders

Cytogenetics

Molecular Diagnostics in Hematopathology

Flow Cytometric Analysis in Hematologic Disorders

Myeloproliferative Neoplasms

Myelodysplastic Syndromes

Acute Leukemias

Mature Lymphoid Neoplasms

Normal Hemostasis and Coagulation

Hemorrhagic Disorders and Laboratory Assessment

Thrombotic Disorders and Laboratory Assessment

Thrombocytopenia and Thrombocytosis

Qualitative Disorders of Platelets and Vasculature

Antithrombotic Therapies and their Laboratory Assessment

Hemostasis and Coagulation Instrumentation

Pediatric and Geriatric Hematology and Hemostasis

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