18-1
Content Outline
Bonewit: Clinical Procedures for Medical Assistants, 8th Edition
Chapter 18: Hematology
Content Outline
Introduction to Hematology
1. Hematology:
a. Includes
2. Laboratory analysis in hematology
a. Purpose: examining blood to detect pathologic conditions
b. Includes
c. Determines if each blood component falls within its reference range
3. Specific hematology tests
a.
b.
c.
d.
e.
f.
g.
4. Complete blood count (CBC)
a.
- Performed on
-New patients
-Patients with a pathologic condition
b. Tests included in a CBC
Components and Function of Blood
1.
a. Plasma:
b. Cells:
2. Average adult body:
1. In an adult:
a.
b.
c.
d.
e.
2. Immature form:
a.
3. Hemoglobin
a.
b.
c.
d. Reference range
- Women:
- Men:
e. Hemoglobin molecule consists of
f.
- Oxygen
- Hemoglobin:
(1)
(2)
(a)
(b)
- Carbon dioxide
g. Arterial blood
h. Venous blood
5. Average life span of RBC:
a. Hemolysis:
- Hemoglobin breaks down into
(1) Iron:
(2) Globin (protein):
(3) Bilirubin
(a)
(b)
(c)
(4)
Leukocytes
1.
2. Leukocytosis:
3. Leukopenia:
4. Function of leukocytes:
a.
b.
5.
a.
6.
a.
7.
a.
b.
c.
Thrombocytes
1.
2.
3.
4.
5. Function:
Hemoglobin Determination
1. Hemoglobin (Hgb):
2.
3.
4. Normal range
a. Female:
b. Male:
5.
6. Decreased hemoglobin level:
a.
b.
c.
d.
e.
f.
- Leukemia
- Hodgkin’s disease
7. Increased hemoglobin level:
a.
b.
c.
Hematocrit-
1.
2. Hematocrit means
a.
- By centrifuging an anticoagulated blood specimen
b.
c. Top layer:
d. Between layers
- Buffy coat:
3. Purpose of hematocrit:
4. Normal range
a. Women:
b. Men:
5. Low reading:
6. High reading:
7. Used with other tests to diagnose the patient’s condition
White Blood Cell Count
1.
2. Adult reference range:
3. Leukocytosis:
a. Most commonly seen in acute infections
b. Normal elevation can occur in
4. Leukopenia:
a.
b.
c.
Red Blood Cell Count
1.
2. Performed using blood cell counter
3. Decrease in red blood cell count
a.
b.
c.
4. Increase in red blood cell count
a.
b.
c.
Red Blood Cell Indices
2.
3.
4.
5.
White Blood Cell Differential Count
1.
a.
b.
c.
d.
2. Purpose of diff
a.
- Increase or decrease in one or more types
- Assists physician in making a diagnosis
3.
Types of White Blood Cells
1.
a. Granular:
b. Nongranular:
2. Description of WBCs
a. Neutrophils: 50% to 70%
b. Eosinophils: 1% to 4%
c. Basophils: 0% to 1%
d. Lymphocytes: 20% to 35%
e. Monocytes: 3% to 8%
3. Reference range for diff count
a. Neutrophils: 50% to 70%
b. Eosinophils: 1% to 4%
c. Basophils: 0% to 1%
d. Lymphocytes: 20% to 35%
e. Monocytes: 3% to 8%
PT/INR
- Combination of:
a.
b.
2. Calculation performed on PT test
• To arrive at a standardized value
-Known as an INR (International Normalized Ratio)
3. PT/INR result
a.
b. Does not have a unit of measurement attached to it
c. Healthy individual with a normal clotting ability
- Should have a PT/INR result that
d.
- Example: PT/INR of 3.0
-
e.
4. Purpose
- Brand names
-
-
c. PT/INR test:
d. Warfarin prescribed for:
e.PT/INR
-Unexplained nosebleeds
-Excessive bleeding from gums
-Easy bruising
-Heavy menstrual periods
-Unexplained blood in the stool or urine
f. Goal of warfarin therapy
- Increase clotting time to a level that prevents formation of blood clots
-Without causing excessive bleeding or bruising
g. Patient must undergo periodic PT/INR testing
- To ensure the patient remains in his or her ideal PT/INR range
-Minimizes complications of warfarin therapy
h.Frequency of testing depends on:
- Stability of patient’s previous test results
- Occurrence of conditions that may cause test results to fall outside of the patient’s desired range
i. When patient first placed on warfarin therapy:
- PT/INR test performed once or twice a week
-To assess patient’s response to warfarin
- Based on PT/INR results
-Dosage adjusted so that:
(1) Results become stable
(2) Consistently fall within patient’s ideal PT/INR range
j.Once test results become stabilized:
- Patient should have a PT/INR test performed every 2 to 4 weeks
k. If the PT/INR result is outside of the patient’s predetermined ideal range
- Physician adjusts warfarin dosage
-To bring patient back into optimal range
l. Other factors that can affect the PT/INR results
- Change in diet
- Prescription and OTC medications that interact with warfarin
- Vitamins
- Herbal preparations
- Change in level of exercise
- Illness
- Smoking
- Alcohol consumption
m. Important forthe patient to keep the physician informed
-Of factors that may alter their body’s response to warfarin
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