Clinical laboratory automation process control

Billions of tests are run annually in clinical chemistry laboratories automation has therefore played a large role there. In the preceding sections, automated process-control systems were described. The first part of the present section describes the needs of the clinical chemistry laboratory as they relate to automation. The remainder will be devoted primarily to how clinical instruments are automated and which instrumental methods are most commonly used. Selected instruments will be described. 

Immunosensors promise to become principal players ia chemical, diagnostic, and environmental analyses by the latter 1990s. Given the practical limits of immunosensors (low ppb or ng/mL to mid-pptr or pg/mL) and their portabiUty, the primary appHcation is expected to be as rapid screening devices ia noncentralized clinical laboratories, ia iatensive care faciUties, and as bedside monitors, ia physicians offices, and ia environmental and iadustrial settings (49—52). Industrial appHcations for immunosensors will also include use as the basis for automated on-line or flow-injection analysis systems to analyze and control pharmaceutical, food, and chemical processing lines (53). Immunosensors are not expected to replace laboratory-based immunoassays, but to open up new appHcations for immunoassay-based technology. 

Automation has been applied for a number of years in process control instrumentation, but the major impetus to introduce automatic devices into laboratories stems from three sources (1) the introduction of the continuous-flow principles as outlined by Skeggs [1] (2) the general demand for clinical chemical measurements, which represents a ready and sizeable market for instrument companies, and, more importantly, (3) the abihty to handle large volumes of data and package them in a form suitable for presentation to analysts and customers, through the use of mini- and micro computer systems hnked to a control computer. 

The first fully automated instrument for chemical analysis (the Technicon Auto Analyzer ) appeared on the market in 1957. This instrument was designed to fulfill the needs of clinical laboratories, where blood and urine samples are routinely analyzed for a dozen or more chemical species. The number of such analyses demanded by modern medicine is enormous, so it is necessary to keep their cost at a reasonable level. These two considerations motivated the development of analytical. systems that perform several analyses simultaneously with a minimum input of human labor. The use of automatic instruments has spread from clinical laboratories to laboratories for the control of industrial processes and the routine determination of a wide spectrum of species in air, water, soils, and pharmaceutical and... 

B4. Blaivas, M. A., Application of a process control computer in the automated clinical chemistry laboratory. In "Automation in Analytical Chemistry (L. T. Skeggs, Jr., ed.), pp. 452-454. Mediad, New York, 1966. 

The services of the analytical chemist are constantly increasing as more and better analytical tests are developed, particularly in the environmental and clinical laboratories. The analyst often must handle a large number of samples and/or process vast amounts of data. Instruments are available that will automatically perform many or all of the steps of an analysis, greatly increasing the load capacity of the laboratory. The data generated can often be processed best by computer techniques computers may even be interfaced to the analytical instruments. An important type of automation is in process control whereby the progress of an industrial plant process is monitored in real time (i.e., online), and continuous analytical information is fed to control systems that maintain the process at preset conditions. 

One of the major developments in analytical chemistiy during the last few decades has been the appearance of commercial automated analytical sterns, which provide analytical and control information with a minimum of operator intervention. Automated systems first appeared in clinical laboratories, where thirty or more specie,t are routinely determined for diagnostic and screening purposes. Laboratory automation soon spread to industrial process control and later to pharmaceutical, environmental, forensic, governmental, and university research laboratories. Today, many routine determinations as well as many of the most demanding analyses are made with totally or partially automated systems. 

The Clinical Laboratory Environment. The task of the clinical chemist is to perform chemical analyses for diagnostic purposes. The concepts described in the first part of this chapter can be applied because of the common theme of automation for chemical analysis however, the automation requirements in the clinical laboratory significantly differ from those in either process control or industrial analytical chemistry. 

A prime objective of automation is to eliminate the need for human intervention in a process. Although this may be applied literally in, for example, process control, the clinical laboratory environment described above requires more constraints. Skilled human judgment is essential for monitoring the viability of the sample and the validity and significance of the results. Therefore, automation is aimed at aiding the clinical analyst in the exercise of these skills. 

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