Chapter 32: Hematology

What is the range for a PT/INR result of a healthy individual with a normal clotting ability?

0.8 to 1.2.

What is the PT adult reference range?

10 to 20 seconds.

What is the usual desired PT/INR range for a patient who is on warfarin therapy for a heart attack or stroke?

2.0 to 3.0.

What is the normal range for the white blood count for an adult?

4500 to 11,000 white blood cells per cubic millimeter of blood.

List examples of conditions that may result in leukocytosis.

Acute infections such as appendicitis, chickenpox, diphtheria, infectious mononucleosis, meningitis, and rheumatic fever.

Why is it important to fill the blood tube for a PT/INR test to the exhaustion of the vacuum?

An underfilled tube results in an incorrect anticoagulant-to-blood ratio, which can lead to inaccurate test results.

List five conditions that cause a decrease in the hemoglobin level.

Anemia, hyperthyroidism, cirrhosis of the liver, severe hemorrhaging, hemolytic reactions, leukemia, Hodgkin's disease.

What is the purpose of performing an INR on a PT test?

Calculating the INR allows a patient's PT test results to be compared regardless of the testing reagent or laboratory used to run the test.

How often should a patient on warfarin therapy have a PT/INR test performed?

Every 2 to 4 weeks.

What are the most common conditions for which warfarin is prescribed?

Heart attack, stroke, thrombophlebitis, recurring atrial fibrillation, heart valve replacement with a mechanical valve, signs and symptoms of a coagulation disorder.

What information is provided by the RBC indices?

Information on the size and hemoglobin content of the patient's red blood cells.

What color-stoppered tube should be used to collect a specimen for a PT/INR test?

Light blue-stoppered tube.

What are the red blood cell indices?

Measurements that are reported as part of the CBC.

List the five types of white blood cells and the normal adult range for each.

Neutrophils, 40% to 75%. Eosinophils, 1% to 6%. Basophils, 0% to 2%. Lymphocytes, 20% to 40%. Monocytes, 3% to 10%.

What are the advantages of PT/INR home testing?

Patient does not have to make periodic visits to a laboratory or medical office to have the test performed; patient can test blood without a laboratory order when conditions occur that may indicate a problem, and treatment can be instituted immediately.

What does the PT test measure?

The PT test measures the length of time that it takes for an individual's blood to form a clot.

What is the goal of warfarin therapy?

To increase the clotting time to a level that prevents the formation of blood clots without causing excessive bleeding or bruising.

What is the function of warfarin?

To inhibit the formation of blood clots in the body.

What is the purpose of the hematocrit?

To measure the percentage volume of packed red blood cells in whole blood.

List the tests generally included in a complete blood cell count (CBC).

White blood cell count, red blood cell count, platelet count, hemoglobin level, hematocrit, differential white blood cell count, and red blood cell indices.

Why must the white blood cells be stained when performing a manual differential cell count?

White blood cells are clear and colorless and must be stained to be identified.

What is the normal hemoglobin range? a. Adult female: b. Adult male:

a. Adult female: 12 to 16 g/dl. b. Adult male: 14 to 18 g/dl.

What is the normal hematocrit range? a. Adult female: b. Adult male:

a. Adult female: 37% to 47%. b. Adult male: 40% to 54%.

What is the normal range for the red blood count for an adult? a. Adult female: b. Adult male:

a. Adult female: 4 to 5.5 million per cubic millimeter of blood. b. Adult male: 4.5 to 6.2 million per cubic millimeter of blood.

What are the advantages of the following methods for performing a differential cell count? a. Automatic method: b. Manual:

a. Automatic method: Faster and more convenient. b. Manual: Allows for the closer inspection of abnormal white blood cells.

List the abbreviation for each of the following tests: a. Hematocrit: b. Hemoglobin: c. Differential cell count: d. White blood cell count:

a. Hematocrit: Hct b. Hemoglobin: Hgb c. Differential cell count: diff d. White blood cell count: WBC e. Red blood cell count: RBC