MLAB 2401: C LINICAL C HEMISTRY K ERI B ROPHY -M ARTINEZ Assessment of Acid-Base Balance.
P RINCIPLES OF C LINICAL C HEMISTRY A UTOMATION. A UTOMATION I N C LINICAL C HEMISTRY The modern...
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Transcript of P RINCIPLES OF C LINICAL C HEMISTRY A UTOMATION. A UTOMATION I N C LINICAL C HEMISTRY The modern...
AUTOMATION IN CLINICAL CHEMISTRY
The modern clinical chemistry laboratory uses a high degree of automation.
Many steps in the analytic process that were previously performed manually can now be performed automatically.
This Permits the operator to focus on tasks that cannot be readily automated and increasing both efficiency and capacity.
AUTOMATION IN CLINICAL CHEMISTRY
The analytic process can be divided into three major phases— preanalytic, analytic, and postanalytic—corresponding to sample processing, chemical analysis, and data management, respectively.
Substantial improvements have occurred in all three areas during the past decade.
The analytic phase is the most automated, and more research and development efforts are focusing on increasing automation of the preanalytic and postanalytic processes.
WHY AUTOMATION? Increase the number of tests by one
person in a given period of time Minimize the variations in results from
one person to another Minimize errors found in manual
analyses – equipment variations – pipettes
Use less sample and reagent for each test
TYPES OF ANALYZERS Continuous Flow
Tubing flow of reagents and patients samples
Centrifugal analyzer Discrete
Separate testing cuvets for each test and sample
Random and/or irregular access
CONTINUOUS FLOW
This first “AutoAnalyzer” (AA) was a continuous-flow, single-channel, sequential batch analyzer capable of providing a single test result on approximately 40 samples per hour.
Analyzers with multiple channels (for different tests), working synchronously to produce 6 or 12 test results simultaneously at the rate of 360 or 720 tests per hour.
In continuous flow analyzers, samples were aspirated into tubing
to introduce samples into a sample holder,
bring in reagent, create a chemical reaction, and then pump the chromagen
solution into a flow-through cuvette for spectrophotometric analysis.
CONTINUOUS FLOW
CONTINUOUS FLOW
• The major drawbacks that contributed to the eventual demise of traditional continuous-flow analyzers in the marketplace were significant carry-over problems and wasteful use of continuously flowing reagents.
CONTINUOUS FLOW
Continuous flow is also used in some spectrophotometric instruments in which the chemical reaction occurs in one reaction channel and then is rinsed out and reused for the next sample, which may be an entirely different chemical reaction.
DISCRETE ANALYZERS
Discrete analysis is the separation of each sample and accompanying reagents in a separate container.
Discrete analyzers have the capability of running multiple tests on one sample at a time or multiple samples one test at a time.
They are the most popular and versatile analyzers and have almost completely replaced continuous-flow and centrifugal analyzers.
DISCRETE ANALYZERS
Sample reactions are kept discrete through the use of separate reaction cuvettes, cells, slides, or wells that are disposed of following chemical analysis.
This keeps sample and reaction carryover to a minimum but increases the cost per test due to disposable products.
WITH AUTOMATION THERE IS STILL SOME VERY BASIC STEPS
Specimen preparation and Identification Labeling still critical Programming of instrument
Laboratory personnel must perform and observe:Quality AssuranceQuality Control
SELECTION PROCESSWhat is your lab’s workload like?
Discrete or large batch testing?Single instrument or multiples?
Storage of reagentsNeed refrigeration or freezing?
expenseKept at room temperature until
reconstituted
DEFINITION Point-of-care testing (POCT) has been
defined by the College of American Pathologists (CAP) as “those analytical patient-testing activities provided within the institution, but performed outside the physical facilities of the clinical laboratories.”
PLACE OF ANALYSIS Physician’s offices Operating rooms Emergency rooms Intensive Care Units Home health care Patient performed
PERSONNEL ISSUES Most often performed by non-laboratorians Physicians Nurses or nurses aides Respiratory technicians Not specifically trained in the requirements
for accurate testing and interpretation
LABORATORY SUPPORT
Laboratory still responsible for results
Therefore responsible for training and management of POCT programs
Laboratory must build a structure to support and facilitate POCT
SUPPORT STAFF Director - PhD, MD or laboratory
scientist or pathologist POC Coordinator – laboratory scientist
with high level technical & interpersonal skills
POC Trainers – designated person(s) for problem solving etc.