Diagnostic Tests Flashcards
Why undergo Diagnostic Testing
- Tools that provide information
- Tests may be used for basic screening as part of a wellness check
- Tests are used to help confirm a diagnosis, monitor an illness and provide valuable information about the clients response or treatment
What are the 3 diagnostic testing phases
Pretest
Intratest
Posttest
The major focus of this phase is client preparation
Pre-test
Common questions that are included in Pre-test
- What sample will be needed and how will it be collected
- Does the client need to stop oral intake for a certain number of hours prior to the test?
This phase focuses on specimen collection and performing or assisting with certain diagnostic testing
Intra-test
Why does the nurse need to ensure correct labeling, storage and transportation of the specimen?
To avoid invalid test results
This phase focuses on the nursing care of the client and follow-up activities and observations
Post-test
What does the nurse compare during Post-test
Current and previous tests results and modifies nursing interventions as needed`
Nursing Diagnoses in Diagnostic tests
Anxiety
Lack of Knowledge
Fear
related to possible diagnosis of accurate or chronic illness
Anxiety
related to insufficient information regarding the process for test
Lack Of Knowledge
Related to the pending conclusion of the diagnostic test
Fear
Commonly used in diagnostic test that can provide valuable information about hematologic system and many other body systems.
Blood Tests
Performed through a venipuncture by a Phlebotomist
Bloodtest
Puncture of a vein for collection of a blood specimen
Venipuncture
an individual who performs venipuncture
Phlebotomist
includes hemoglobin and hematocrit measurements, erythrocyte (RBC) count, red blood cell indices, leukocyte (WBC) count, and differential white blood cell count
Complete blood count (CBC)
Most basic screening test
Complete blood test (CBC)
The main intracellular protein of erythrocytes
Hemoglobin (HGB)
it is the iron-containing protein in the RBC that transports oxygen through the body
Hemoglobin (HGB)
What is the pigment of Hemoglobin? and what does it contain?
Pigment : Heme
and it contains iron and protein (globin)
Hemoglobin count of Men and Women
Men - 13.5 - 18 g/dl
Women - 12 - 15 g/dl
(grams per deciliter)
Causes of increased HGB
Polycythemia, Dehydration, COPD (chronic pulmonary disease), Heart failure
Causes of decreased HGB
Blood loss, anemia, kidney disease, cancers
Measures the percentage of RBCs in the total blood volume
Hematocrit (HCT)
is a fastest way to determine the percentage of RBCs in the plasma
Hematocrit or Packed cell volume
Why is HCT reported as a percentage?
because of concentration of RBCs in the blood
Total % of plasma of blood
55% of total blood
Total % of Erythrocytes of total blood
45% of total blood
Percentage of buffy coat of total blood (leukocytes and platelets)
<1% of total blood
Normal HCT count in men and women
Men - 40-54%
Women - 36-46%
causes of increased HCT
Dehydration
Hypervolemia
Diabetic Acidosis
Burns
causes of decreased HCT
Acute blood loss
Pregnancy
Dietary Deficiencies
Anemias
The number of RBCs per cubic millimeter of whole blood`
Red blood cell (RBC) Count
Low RBC counts are indicative of what condition
Anemia
Clients with chronic hypoxia may develop higher than normal count, a condition known as?
Polycythemia
RBC indices may be performed as a part of the CBC to evaluate the
Size, weight, and HBC Concentration of RBCs
What is the mean of average size of the individual RBC
Mean Corpuscular volume (MVC)
Normal MCV
80 - 98 per µm3 (cubic micrometer)
Causes of increased MCV
Chronic liver disease, Pernicious Anemia
Causes of Decreased MCV
Iron Deficiency anemia, Lead poisoning
the amount of HGB present in one cell is called
Mean Corpuscular Hemoglobin (MCH)
Normal count of MCH
27 - 31 pg (picograms)
causes of increased And Decreased MCH
Macrocytic Anemia
the proportion of each cell occupied by HGB
Mean Corpuscular Hemoglobin Concentration (MCHC)
Causes of decreased MCHC
Microcytic Anemia
Hypochromic anemia
normal % of MCHC
32 - 36%
Determines the number of circulating WBCs per cubic millimeter of whole blood
White blood cell (WBC) count
Where are high WBC count seen
In the presence of a bacterial infection
When can WBC count be low
If a viral infection is present
This information is useful for diagnosing certain disorders
WBC count
Normal WBC count for adults
4500 - 10,000 mm3
causes of increased WBC count
Acute infections
tissue necrosis
Causes of decreased WBC count
Viral infections
Hematopoietic diseases
Rheumatoid Arthritis
The proportion of each of the five types in a sample of 100 WBCs
WBC Differential Count
normal % of Neutrophils
50-70%
causes of increased Neutrophils
Acute infections
causes of decreased Neutrophils
Viral diseases, Luekemias, Aplastic and Iron Deficiency Anemia
Normal % of Lymphocytes
25-35%
Causes of increased Lymphocytes
Viral infection, Chronic infections, Lymphocytic Leukemia
Causes of decreased Lymphocytes
Cancers
Leukemia
Multiple Sclerosis
Renal Failure
Normal % of monoctyes
4-6%
Cause of decreased and Increased monocytes
Increased: Viral infection, Hodgkin’s Disease
Decreased: Lymphocytic Leukemia, Aplastic Anemia
Normal % of Eosinophils
1-3%
Causes of increased Eosinophils
Allergic reactions
Phlebitis
Cancer
Parasitic Infections
Causes of decreased Eosinophils
- Stress (burns, shock)
- Adrenocortical Hyperfunction
Normal % of Basophils
0.4 - 1.0%
Causes of Increased Basophils
Leukemia
Inflammatory Process
Causes of Decreased Basophils
-Hypersensitivity
Reaction
- Stress
- Pregnancy
Are cells that help blood clots
Platelets
Normal finding of platelets
150,000 - 400,000 microliters
Causes of increased Platelet count
Pulmonary embolism
Polycythemia vera
Acute blood loss
Splenectomy
Causes of decreased Platelet count
-Idiopathic
-Thrombocytopenic Purpura
- Cancer
- Systemic Lupus Erythematosus (SLE)
Normal Values of
Sodium
Potassium
Chloride
Calcium (ionized)
Magnesium
Phosphate
Serum Osmolality
Sodium: 135 - 145 mEq/L
Potassium: 3.5 - 5.3 mEq/L
Chloride: 95 - mEq/L
Calcium (ionized) - 4,5-5.5 mEq/L or 8.5 - 10.5 mg/dL
56% of total calcium (2.5 mEq/L or 4.0-5.0mg/dL)
Magnesium: 1.5 - 2.5 mEq/L or 1.6 - 2.5 mg/dL
Phosphate: 1.8 - 2.6 mEq/L or 1.6-2.5 mg/dL
Serum Osmolality: 280 - 300 mOsm/kg water
is the measure of the solute concentration of the blood
Serum Osmolalty
What is included in Serum Osmomality
Sodium ions
Glucose and urea (BUN)
how can serum osmolality be estimated
By doubling the serum sodium
What are osmolality values for
to evaluate fluid balance
Normal values of Serum Osmolality
280 - 300 mOsm/kg
what does an increase of osmolality indicate
a Fluid deficit
is often conducted when a client is taking a medication with a narrow therapeutic range
Therapeutic Drug monitoring
what does a decrease of osmolality indicate
Volume excess
indicates the highest concentration of the drug in the blood serum
Peak level
represents the lowest concentration of drug in the blood serum
Trough level
what is the ideal client peak and trough levels
within the therapeutic range
is a commonly used diagnostic tool to evaluate the partial pressures of gas in blood and acid base contenent
Blood Gas analysis
what does Blood gas analysis evaluate
Partial Pressures of gas in blood and acid base content
where is the specimen taken in arterial blood
radial, brachial, and femoral arteries