Chapter 3: Automation - Austin Community College
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Transcript Chapter 3: Automation - Austin Community College
MLAB 2401: Clinical Chemistry
Keri Brophy-Martinez
Automation
History of Automation
• 1957
– Technicon develops the first automated analyzer
• Continuous flow
• Issues: carryover and costly
• 1970
– Dr Anderson(NASA) develops a centrifugal analyzer
– DuPont ACA revolutionized chemistry with a non-continuous flow, discrete
analyzer with random access availability
• 1976-1978
– Kodak Ektachem: dry slide technology
• Small volumes of sample
• Reagents on slides for dry chemistry analysis
• 1980-Present
• Discrete analyzer take over Chemistry
• “walk-away” capabilities
Ektachem & ACA
• http://tiny.cc/n6pw2
Drivers For Technology Advances
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Reduction in TAT’s
Staff shortages
Economic factors
Increase throughput
Reduction in lab error
Increase safety
24/7 operations
Focus on automation of tasks rather than
manual methods
Automated Chemistry Analyzers
• Advantages
– Increased number of tests/technologist
• each tech can perform more tests during a period
of time
– Minimizes variations in results
• eliminates errors in pipetting, calculations
– Small sample size and reagent volumes
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Automated Chemistry Analyzers
• Disadvantages
– Methods vary with the instrument type, etc.
– Generally, cost of equipment, maintenance,
amount of QC
– Techs must be kept knowledgeable & careful in
set-up and operations
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Basic Types of Instruments
• Continuous flow
• Centrifugal analysis
• Discrete analysis
• Batch analyzer
– perform only test that is requested
– can perform many combinations of tests
– do not consume reagents for tests not ordered
– Continuous flow, centrifugal and discrete analyzers can all use batch
mode
Automated Chemistry Instruments
• Continuous flow analysis
– Reagents are pumped continuously through the system.
– Samples are introduced sequentially at timed intervals and follow each
other through the same network of tubing coils, heating baths and
photometer / other detector.
– While economical for profiles of tests, not good for stats or single
order tests.
– All samples get all tests, ordered or not
– Could not easily interrupt the process once initiated.
– *Also prone to “carryover”.
– Wasteful of reagents
– Example: Chem 1 By Technicon
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Automated Chemistry Instruments
• Centrifugal analysis
– A discrete system where the transfer of
solutions is carried out by the use of
centrifugal force
– Runs multiple samples, one test at a time
– Example:
• Cobas-Bio and IL Monarch
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Automated Chemistry Instruments
• Discrete analysis
Each sample is contained in a
separate reaction vessel
Make up the majority of modern
chemistry analyzers
Run multiple tests one sample at
a time or multiple samples one
test at a time called RANDOM
sampling
Examples:
Dade Behring Dimension
RXL
Kodak Ektachem
Alfa Wasserman Ace Alera
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Automated Chemistry Systems
• Wet chemistry systems
– Reagents come ready to use or lyophilized and
must be reconstituted
– Systems include batch and profile analyzers or
stat analyzers
• Examples: Beckman Coulter CX-7, Vitros, Dade,
Advia, Roche Integra, Hitachi, Alfa Wasserman Ace
Aleria, etc.
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Automated Chemistry Systems
• Dry reagent systems
Reagents can be tablets or found on cellulose
fibers located on strips, cards, or layered on
film.
Reagents easy to handle, store well, and have
fairly long shelf life.
Examples: Vitros, Seralyzer, Kodak Ektachem,
ChemPro, Dupont Analyst
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Automated Chemistry Analyzers
• Concepts and definitions
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Automated Chemistry: Terms
– Throughput
– Max # samples that can be processed in 1
hour
– Dwell time
– minimum amount of time required to get
test result after sampling
• varies greatly with instrument
• can be important consideration when selecting
instrument
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Automated Chemistry:Terms
• Stat testing
– Latin statum = immediate
– a widely used (abused) word in the lab, used to
prioritize work
– Stat turn around time - within 1 hour after order
entry
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Costing of chemistry lab tests
• Things that are included in pricing
– labor – processing
– equipment maintenance
– reagents - including a portion of start-up
– calibration and QC
– consumables - containers, paper
– capital - proportionate amt of life of instrument
– hospital overhead - facility maintenance
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Automated Chemistry
• Test repertoire
– What tests the instrument is capable of doing
• Consider cost analysis
– Immediate test repertoire
• What it can do without any changes (set- up or
programmed for)
– Total test repertoire
• Total number of tests that can be performed on the
instrument, with a few changes, ie. reagents, filters or
components.
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Analytic Phases
• Preanalytic
• Analytic
• Postanalytic
Preanalytic Phase
• Specimen collection
– Right tube for right tests
– Proper patient label
– Correct draw site
• Specimen transport
– Phlebotomists
– Volunteers
– Pneumatic-tube systems
Analytic Phase
• Sample handling
– Important to check the specimen for hemolysis,
lipemia, clots or fibrin
– Some analyzers use closed-tube,some open-tube
– Most instruments utilize a level-sensing probe to
detect the amount of serum or plasma in a tube
Summary of Analyzer Operations
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Sample identification: bar code or manual read
Determination of tests to be performed: LIS can communicate this
or operator
Reagent systems and delivery: reagents dispensed into cuvet
Specimen measurement and delivery: sample aliquot in
introduced into reaction cuvet
Chemical reaction phase: Sample and reagents mixed and
incubated
Measurement phase: Optical readings
Signal processing and data handling: Concentration is estimated
from a calibration curve stored in analyzer
Send results to LIS or read and entered off results tape
Postanalytical Phase
• Bidirectional communication
• Decreases opportunity for error
• Auto-verification
Trends
• Total Laboratory Automation (TLA)
– Integrated work cells
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Specimen manager
Track system
Immunoassay
Chemistry
References
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Bishop, M., Fody, E., & Schoeff, l. (2010). Clinical Chemistry: Techniques, principles, Correlations. Baltimore:
Wolters Kluwer Lippincott Williams & Wilkins
http://ashepages.com/productshowcase.php?ps_id=6574
http://www.asdiagnostics.co.uk/products/clinical-chemistry.php
http://www.clpmag.com/issues/articles/2008-02_02.asp
http://www.mann-horton.com/chem1.htm
http://websites.labx.com/rankin/detail.cfm?p=0&autonumber=1104
http://www.idsys.com/multitest-blood-analyzer/
http://www.idexx.com/view/xhtml/en_us/smallanimal/inhouse/vetlab/common/dry-slide-animation.html
http://www.southtexasblood.org/blood_general_facts.asp
Sunheimer, R., & Graves, L. (2010). Clinical Laboratory Chemistry. Upper Saddle River: Pearson .