Chapter 11 of ECE course at Western UniversityDescripción completa
Hayt EEM 8th solution manual.
Full description
IMF - Chapter 11Full description
For engineering courseDescripción completa
Full description
system design manual
Hayt EEM 8th solution manual.
Descrição: Chapter 11 of ECE course at Western University
Hayt EEM 8th solution manual.
Full description
For engineering courseFull description
Chapter 11 CLINICAL LABORATORY INSTRUMENTATION - Clinical Laboratory : Laboratory : responsible for analyzing patient specimens in order to provide information to aid in the diagnosis of disease and evaluate the effectiveness of therapy - Hospital Department : Department : Dept. of Clinical Pathology Dept. Of Laboratory Medicine
- Major Section :
Chemistry, Hematology, Microbiology, Blood bank
CLINICAL LABORATORY z
Chemistry section – Analysis on blood, urine, CSF, and other fluid – To determine clinically important substances – Most applications of electronic instrumentation in the clinical laboratory
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Hematology section – Determination of numbers and characteristics of the formed elements in the blood (RBC, WBC, and PLT) – Tests of function of physiological systems in the blood (e.g. clotting study) – Automated on Coulter Counter
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Microbiology section – Studies on various body tissues and fluids to determine whether pathological microorganisms are present – Little electronic instrumentation
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Blood bank – Little electronic instrumentation
CLINICAL LABORATORY z
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Accuracy Precision Fast response Laboratory information system (LIS) : - A LIS is a class of software which handles receiving, processing and storing information generated by medical laboratory processes. These systems often must interface with instruments and other information systems such as hospital information systems (HIS).
11.1 SPECTROPHOTOMETRY z
Principle : substances of clinical interest selectively absorb or emit electromagnetic energy at different wavelengths. -
measures the light transmitted and absorbed as it passes through a sample. use prism or diffraction gratings to break light into spectrum of color
11.1 SPECTROPHOTOMETRY
Factors that Determine Transmitted Light Intensity
Beer's Law Plot
Example of change in color as concentration of solution increases
11.1 SPECTROPHOTOMETRY z
Diffraction grating −
color( )
Fig. 11.1 A diffraction grating showing an incident beam of white light, and a
11.1 SPECTROPHOTOMETRY z
Flame Photometer: -
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Power source and sample-holder function are combined in the flame Sample’s emission rather than absorption Only for concentrations of pure metals analyze urine or blood to measure the concentration of K+ and Na+ Li+ , not found in biological sample, used as internal standard
Flame Photometer
Fig. 11.2 A flame photometer functional diagram
Fluorometry z
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an analytical technique for identifying and characterizing minute amounts of a substance by excitation of the substance with a beam of ultraviolet light and detection and measurement of the characteristic wavelength of fluorescent light emitted. (Fig. 11.3) Advantage : Much greater sensitivity Disadvantage : Sensitivity to temperature and pH of the sample
11.2 AUTOMATED CHEMICAL ANALYZER Beckman Synchron CX4 Delta Type
Chemistry Analyzer
Parameters
69 analytes
Throughput
225 samples / hour
Method
Spectrophotometric
Open system
YES
Total Laboratory Automation an Accelnet modular lab automation system uses robotics to free technicians from the most laborintensive tasks in a lab, such as sorting samples and loading and unloading the centrifuge.
Core lab design emphasizes automation in the most labor-intensive areas of clinical Front-end automation using a Power Processor (Beckman laboratory testing.
Total Laboratory Automation UniCel® DxC 800 Synchron® Clinical System
Power Processor Sample-Handling System UniCel® DxI 800 Connection
Intelligent Aliquotter
Hematology Outlet
DL2000 or Remisol 2000 Data Manager
Specimen Stockyard
Command Central Workstation
11.3 CHROMATOLOGY z
Chromatology : a group of methods for separating a mixture of substances into component parts – useful in determining what drug or drugs have been taken in overdose cases. – fixed phase (liquid or solid), mobile phase (gas or liquid) – Partition : for liquid stationary phase – Adsorption : for solid stationary phase – Difference in the rate of movement of components of mixture in the mobile phase, caused by interaction of these components with the stationary phase, are used to separate the components
11.4 ELECTROPHORESIS z
Electrophoresis : used in clinical laboratory -
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to measure quantities of the various types of proteins in plasma, urine, and CSF (cerebrospinal fluid) to separate enzymes into their component isoenzymes to identify antibodies to serve in a variety of other applications.
Principle : the movement of a solid phase with respect to a liquid (the buffer solution) Factors affecting the speed of migration -
Magnitude of charge Ionic strength of buffer Temperature Time Types of support media
Hematocrit (ht) : 40 – 54(%) adult men, 35-47% adult women = [ height of packed cell / height of blood ] with centrifuged blood in a tube
11.5 HEMATOLOGY z
Electronic Cell Counter resistance method : “Coulter Counter” size of the blood • orifice resistance change cell in the orifice R • bridge circuit output
Fig. 11.3 A circuit for electronic measurement of blood cell count
Coulter STKS z z
From Coulter Corp. : Fig.11.11-12 Hgb : 1st dilution of 1:224 1:250(lysing agent) -
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WBC : 1st dilution of 1:224 -
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with lysing agent causes cell membrane of RBC to rupture Drabkin’s solution : convert Hgb to cyanmethemoglobin WBC count : magnitude of voltage pulse is related to the volume of the WBC Three parallel counting unit, and then voting circuit & averaging circuit Correct the average-count signal for coincidence (passage of 2 or more WBCs at the same time)
RBC : 2nd dilution of 1:224 -
Cells with volume > 35.9 fl are classified as RBCs Cells with volume = 2~20 fl are classified as PLTs
