• Specimen Management
• Quality Control / Quality Assessment / Total Quality Management
• Automated Chemistry Analyzers
• Arterial Blood Gases*
• Iontophoresis*
• Osmometer
• Proteins and Electrophoresis*
• Therapeutic Drug Monitoring
• Thin Layer Chromatography*
• Urine and Other Body Fluid Chemistries
• Glycated Hemoglobin
• Molecular Diagnostic and Immunologic Assays*

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SPECIMEN MANAGEMENT
Introduction
The chemistry department is responsible for monitoring departmental criteria for specimen acceptance, processing of various testing, evaluating and reporting laboratory results. These factors are essential for quality assessment in the laboratory. In the chemistry department, a considerable amount of effort is placed on specimen handling and collection, since the final results for any analyte are dependent on these two factors. The following precautions or conditions are essential for quality specimens:

• proper identification of patient
• proper labeling of specimen
• state of patient - fasting, nonfasting, etc.
• correct time for specimen collection - drug levels, hormones, etc.
• correct specimen type - anticoagulants, preservatives
• special handling - ice, prechilled tubes, spin immediately, etc.
• proper storage conditions

Prerequisite
The student will familiarize herself/himself with the overall management of the Chemistry Department.

Objectives
Upon completion of this unit, the student will be able to:

1. Discuss the specimen management system used by the chemistry laboratory.
2. Distribute specimens appropriately.
3. State the tests performed at each station or instrument (e.g., Automated Chemistry Instruments, Manual Methods, Special Chemistry, TDM, etc.)
4. Evaluate specimens, using departmental guidelines for acceptance or rejection.
5. Document specimen rejection according to departmental guidelines.
6. Report and/or call results according to laboratory protocol.
7. Maintain and file patient records according to laboratory protocol.

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QUALITY CONTROL / QUALITY ASSESSMENT / TOTAL QUALITY MANAGEMENT
Introduction
Quality is of utmost importance in every laboratory. Today's laboratories have a variety of programs in place to control, assess, and improve their quality.

Prerequisite
The student should read the department's quality control (QC), quality assessment (QA), and total quality management (TQM) and/or continuous quality improvement (CQI)  policies.

Objectives
Upon completion of this unit, the student will be able to:

1. Compare and contrast quality control, quality assessment, and total quality management.
2. Evaluate laboratory QC data and identify appropriate corrective action when data falls out of control range.
3. For each procedure in the chemistry laboratory, discuss how QC is monitored and recorded.
4. Identify QC shifts and trends.
5. Discuss the need for departmental quality assessment and/or total quality management programs.
6. Explain the purpose of proficiency testing.
7. Discuss the role of the medical technologist in maintaining laboratory quality.

AUTOMATED CHEMISTRY ANALYZERS
Introduction
Automated chemistry analyzers are often the workhorse of the routine chemistry laboratory. While instruments vary by manufacturer and type, the following basic objectives remain the same for each analyzer.

Prerequisites
The student should review the Automated Chemistry Analyzer Instrument Manual.

Objectives
Upon completion of this unit, the student will be able to:

1. Evaluate specimen acceptability for analysis based on proper labeling, specimen characteristics (e.g., serum, plasma, hemolysis, lipemia, etc.), sufficiency of volume, and appropriateness of storage method.
2. Identify different types of analyzers, i.e. batch, random access, etc.
3. Identify the basic operating components of the analyzer and explain the function of each.
4. Describe the chemical principles for each test performed on the analyzer.
5. Perform routine daily maintenance.
6. Identify periodic (weekly, monthly, etc.) maintenance requirements.
7. Prepare reagents for use on the analyzer.
8. State how reagents are stored when not in use on the analyzer.
9. Operate the automated chemistry analyzer.
10. Evaluate and record quality control data.
11. State when the analyzer requires calibration.
12. Describe the procedure for calibration.
13. Perform calibration as required.
14. Explain where to find basic troubleshooting information about the analyzer.
15. Justify the importance of documenting maintenance, quality control, and troubleshooting.
16. Correlate patient results with clinical significance.
17. Evaluate inaccurate analyzer results.
18. Report results according to laboratory protocol.

ARTERIAL BLOOD GASES*
Introduction
Arterial blood gases are used to assess acid-base balance and blood oxygen levels. The parameters generally measured are pH, PCO₂, and PO₂. Depending upon the protocol established by a particular hospital, these analyses may be performed either by the laboratory or the respiratory therapy department.

Prerequisites
The student should:

1. Read the Instrument Manual for the Blood-Gas Analyzer.
2. Review acid-base balance.

Objectives
Upon completion of this unit, the student will be able to:
 

1. Evaluate specimen acceptability for analysis based on proper labeling, specimen characteristics (e.g., anticoagulant, etc.), sufficiency of volume, and appropriateness of transport/handling method.
2. Operate the blood-gas analyzer.
• Perform calibration.
• Assay controls and specimens.
3. Evaluate quality control results.
4. Record the gas calibration values, quality control values, patient results and maintenance for each operation.
5. Describe the procedure for changing electrodes.
6. Explain the one and two point calibration procedures.
7. Explain the function of the buffers and flush solutions.
8. Explain the principles of operation for the PO₂, PCO₂, and pH electrodes.
9. Compare and contrast the following acid-base/blood-gas imbalances:
• Metabolic acidosis
• Metabolic alkalosis
• Respiratory acidosis
• Respiratory alkalosis
10. Correlate patient results with the clinical significance of test noting any abnormal result.
11. Maintain patient records according to established protocol.

IONTOPHORESIS*
Introduction
Iontophoresis aids in the diagnosis of cystic fibrosis. After the iontophoretic procedure, the chloride concentration of the sweat may be measured with various methods. One clinical feature of most cystic fibrosis individuals is an increased chloride concentration in the sweat.

Prerequisites
The student should read the Instrument Manual for the Iontophoresis system.

Objectives
Upon completion of this unit, the student will be able to:

1. Explain the principles of iontophoresis and coulometry.
2. Weigh pre- and post-sweat test vials on the analytical balance.
3. Observe one sweat test. (Under no circumstances perform analysis without the guidance of an instructor and adherence to established protocol as explained in procedure manual.)
4. Perform chloride analysis on obtained sweat.
5. Calculate chloride level in obtained sweat.
6. Correlate chloride levels in sweat with clinical significance of testing procedure.
7. List possible sources of chloride contamination in the collection and in analysis of the sweat.
8. Describe the effects of incorrect specimen collection/handling on test results.
9. Explain the significance of sweat testing in children and adults.
10. Explain the diagnostic value of the following laboratory tests and clinical features in relation to cystic fibrosis:
• d-xylose absorption
• Patient history
• Physical symptoms

OSMOMETER
Introduction
Osmolality is a measure of the total number of dissolved particles in solution and is independent of the molecular weight of the particles. Osmolality measurements are made in the clinical laboratory using either a freezing-point depression or vapor-pressure osmometer.

Prerequisite
The student should read the Instrument Manual for the Osmometer.

Objectives
Upon completion of this unit, the student will be able to:

1. Evaluate specimen acceptability for analysis based on proper labeling, specimen characteristics (e.g., urine, serum, plasma, etc.), sufficiency of volume, and appropriateness of storage method.
2. Explain the principles of osmometry and osmolality measurement by freezing-point depression or vapor pressure.
3. Operate the osmometer.
• Perform calibration.
• Assay controls and specimens.
4. Evaluate quality control.
5. Correlate patient results with clinical significance of test.
6. Report laboratory results.
7. Perform required maintenance.
8. Record patient result, quality control and maintenance according to departmental protocol.
9. List the major serum osmotic constituents that affect osmolality.
10. Calculate the serum osmolality from the measured concentrations of these osmotic constituents using a recommended formula.
11. List the significance of the Urine/Serum osmolality ratio as an important tool in evaluating H₂O balance and renal function.
12. Explain the relationship between urine specific gravity and osmolality as an indication of renal concentration ability and how they might be used to establish criteria for hemodialysis.

PROTEINS AND ELECTROPHORESIS*
Introduction
Proteins are composed of amino acids linked by peptide bonds in a sequence and configuration characteristic for each specific protein. There are over one hundred proteins present in plasma serving numerous physiological functions. The ability to vary the charge on a protein molecule by changing the pH of its matrix can be used to purify and characterize proteins by electrophoresis and ion exchange chromatography.

Electrophoresis is the movement of charged particles through an electrical field. In order for electrophoresis to occur, there must be an electrical field, a medium for absorbing and holding the analyte and charged particles. The electrical field is supplied by providing a tank through which current may pass. The charged particles are supplied by using an appropriate buffer for ionizing the molecule. After migration the proteins are stained, and protein bands are identified and quantified. Electrophoresis is useful as a diagnostic technique for the separation of proteins in serum, urine and CSF, for the separation of hemoglobins, and for the separation of serum isoenzymes.

Prerequisites
The student should read the Instrumentation Manual for the Electrophoresis system.

Objectives
Upon completion of this unit, the student will be able to:

1. Evaluate specimen acceptability for analysis based on proper labeling, specimen characteristics (e.g., serum, plasma, whole blood, hemolysis, etc.), sufficiency of volume, and appropriateness of storage method.
2. Explain the basic principle of electrophoresis.
3. Describe factors influencing the mobility and resolution of proteins.
4. Perform the following procedures:
• Serum and urine protein electrophoresis
• Hemoglobin electrophoresis
5. Explain the principles for the tests in #4.
6. Use sample concentrators correctly.
7. Describe the principle of operation of the sample concentrators.
8. Identify the protein fractions on cellulose acetate/agarose electrophoresis.
• Serum and urine protein
• Hemoglobins
9. Interpret protein electrophoresis data in relation to pathological conditions.
10. Perform quality control checks on the densitometer and record according to laboratory protocol.
11. Describe the function of the densitometer operational knobs/switches.
12. Operate the densitometer properly.
13. Prepare patient report forms and record results accurately.
14. Perform troubleshooting when necessary.
15. Discuss the following conditions in relation to structural changes in the hemoglobin molecule.
• Thalassemia
• Sickle Cell Disease
• Sickle/Thalassemia
• Lepore
16. Evaluate the percent of hemoglobins A₁, S, A₂ and F of the total hemoglobin as they relate to the conditions listed in objective 15.
17. Discuss the quantitative methods for differentiating and determining hemoglobins A₂, S and C.
18. List a confirmatory test for Hgb C.
19. Explain the structures of the following hemoglobins.
•  A₁
•  A₂
•  S
• F

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THERAPEUTIC DRUG MONITORING
Introduction
Therapeutic drug monitoring (TDM) is a process by which the quantity of a drug is determined to assist the physician in determining whether a drug dosage should be maintained or altered. Methods used to quantify drugs include sophisticated instrumentation that is capable of performing such assays as Enzyme Immunoassay (EIA), Fluorescence Polarization Immunoassay (FPIA), etc.

Prerequisite
The student should review the Instrument Manual for the Therapeutic Drug Monitoring Analyzer.

Objectives
Upon completion of this unit, the student will be able to:

1. Evaluate specimen acceptability for analysis based on proper labeling, time of collection, specimen characteristics (e.g., serum, plasma, hemolysis, lipemia, etc.), sufficiency of volume, and appropriateness of storage method.
2. Explain the significance of the following selected classes of therapeutic drugs:
• Cardioactive
• Antiepileptic
• Bronchodilator
• Antibiotic
• Antipsychotic
• Antineoplastic
3. For each class of drugs noted in #2, list the generic name of drugs that are commonly ordered.
4. Explain the significance of performing therapeutic drug monitoring.
5. Define the following terminology:
• Therapeutic level
• Toxic level
• Steady-state, peak, and trough concentrations
• Half-life
6. Discuss the significance of peak and trough levels in therapeutic drug monitoring.
7. Differentiate between half-life and steady-state.
8. Explain the principle of enzyme immunoassay.
9. Explain the principle of fluorescence polarization immunoassay.
10. Perform TDM assays employing proper analytical techniques.
11. Assess drug test results for therapeutic management.
12. Recognize abnormal and/or erroneous results.
13. Correlate patient results with clinical significance.
14. Report results according to laboratory protocol.
15. Record patient results, quality control and maintenance according to departmental protocol.

THIN LAYER CHROMATOGRAPHY*
Introduction
Thin Layer Chromatography (TLC) methods are primarily used in the clinical laboratory as a screening tool for identification and separation of certain compounds in biological fluids, (e.g.) drugs. Drug screens are commonly performed on urine specimens, although gastric contents and blood are sometimes used.

Objectives
Upon completion of this unit, the student will be able to:

1. Evaluate specimen acceptability for analysis based on proper labeling, specimen characteristics, sufficiency of volume, and appropriateness of storage method.
2. Explain the principle of Thin Layer Chromatography.
3. List the steps involved in drug detection.
4. Perform urine extraction and concentration for drugs.
5. Spot concentrated extracted urine, controls and standards onto a TLC plate.
6. Migrate plates in appropriate solvents for acidic and basic drugs.
7. Perform detection procedures for visualization of drugs.
8. Interpret patient results by using appropriate standards.
9. Discuss the applications of urine drug screens and the importance of confirming positive drug screens.
10. List the type of analytical systems that may be employed for confirmation purposes.
11. Explain the principle of the confirmatory analytical systems.
12. Identify several factors that will affect migration in TLC.
13. Recognize abnormal and/or erroneous results.
14. Correlate patient results with clinical significance.
15. Report results according to laboratory protocol.
16. Record patient results and quality control according to departmental protocol.
17. Classify the most common drugs of abuse into the following categories noting the drug groups and the generic names: depressant (sedative-hypnotic), depressant (tranquilizer), narcotic, hallucinogen, stimulant, analgesic, antidepressant.

URINE AND OTHER BODY FLUID CHEMISTRIES
Introduction
This section deals with urine chemistries and those body fluid chemistries that require manual manipulation or testing.

Objectives
Upon completion of this unit, the student will be able to:

1. Prepare 24-hour urine containers, and explain collection procedures to patients with minimal supervision.
2. Calculate 24-hour urine results.
•  Protein
•  Creatinine
•  Creatinine clearance
•  Electrolytes
•  Calcium
•  Phosphorus
•  Urea
3. Calculate a 2-hour urine amylase result.
4. Discuss procedures to evaluate other body fluids (CSF, pleural, amniotic, etc.).
5. Perform urine and serum pregnancy tests.
6. Correlate patient results with clinical significance.
7. Report results according to laboratory protocol.
8. Record patient results and quality control according to departmental protocol.

GLYCATED HEMOGLOBIN
Introduction
Glycated hemoglobins, Hb A_1a, Hb A_1b, and Hb A_1c, are modifications of Hb A and are formed by the condensation between glucose and the N-terminal valine amino acid of each beta-chain. The level of glycated hemoglobin depends on the time-averaged glucose concentration during the preceding 6 to 8 weeks before measurement.

Objectives
Upon completion of this unit, the student will be able to:

1. Evaluate specimen acceptability for analysis based on proper labeling, specimen characteristics, sufficiency of volume, and appropriateness of storage method.
2. Explain the principle of the glycated hemoglobin method.
3. Describe why glycated hemoglobin is a better indicator than a random or a fasting blood glucose for evaluating long-term glucose control.
4. Perform the glycated hemoglobin assay using specimens, controls and standards.
5. Evaluate quality control.
6. Correlate patient results with clinical significance.
7. Record patient results and quality control according to departmental protocol.
8. Report results according to laboratory protocol.

1. At each affiliate laboratory, identify the molecular diagnostic assays utilized.
   • Explain the principle of each assay listed in #1.  
   • For each assay listed in #1, discuss its clinical significance (e.g., impact on diagnosis or treatment of associated disease).
   • Perform molecular diagnostic assays available at the affiliate site.
2. List the assays and identify the analyte in the affiliate's laboratory that utilize diagnostic immunologic techniques.
• Explain the principle of each assay listed in #2.
• For each assay listed in #2, discuss its clinical significance (e.g. impact on diagnosis)
• Perform immunological assays offered by the affiliate.

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