Introduction to Instrumentation and IQC PDF

Introduction to Instrumentation and QC and Phases of Analytical Testing Introduction to Instrumentation and QC Objectives Define what is a reagent and its uses in the clinical laboratory Determine the different types of chemicals Define reference materials Be...

Introduction to Instrumentation and QC and Phases of Analytical Testing Introduction to Instrumentation and QC Objectives Define what is a reagent and its uses in the clinical laboratory Determine the different types of chemicals Define reference materials Be able to understand the different grades and specifications of water Review the phases of analytical testing Reagents Pre-packaged and readily available “kit” form Little need for reagent preparation Chemicals Analytic reagent (AR) Ultrapure, Chemically pure (CP) United States Pharmacopeia (USP) National Formulary (NF) Technical or commercial grade Analytic reagent (AR) Suitable for use in most analytic laboratory procedures The chemical meets the specifications of the American Chemical Society Ultrapure, chemically pure (CP) Used in specific procedures such as chromatography, atomic absorption, immunoassays, molecular diagnostics, standardization, or other techniques that require extremely pure chemicals Not recommended for clinical and analytic laboratory use United States Pharmacopeia (USP); National Formulary (NF) Used to manufacture drugs May be pure enough for use in most chemical procedures; however, it should be recognized that the purity standards are not based on the needs of the laboratory Technical or commercial grade Used primarily in manufacturing and should never be used in the clinical laboratory Organic Reagents Practical grade – with some impurities Chemically Pure – purity level of reagent grade chemicals Spectroscopic (spectrally pure) and chromatographic grade organic reagents – purity levels attained by their respective procedures Reagent grade (ACS) – contain impurities below certain levels established by the ACS. Reference Materials Primary standard a highly purified chemical that can be measured directly to produce a substance of exact known concentration and purity ACS purity tolerances for primary standards are 100 + 0.02% Reference Materials National Institute of Standards and Technology (NIST) certified standard reference materials (SRMs) are used instead of ACS primary standard materials. developed certified reference materials/SRMs for use in clinical chemistry laboratories often used to verify calibration or accuracy/bias assessments there are SRMs for a number of routine analytes, hormones, drugs, and blood gases, with others being added. Reference Materials Secondary standard a substance of lower purity with concentration determined by comparison with a primary standard depends not only on its composition, which cannot be directly determined, but also on the analytic reference method Reference Materials Primary VS Secondary standard Water Specifications water is the most frequently used reagent in the laboratory Water solely purified by distillation results in distilled water Water purified by ion exchange produces deionized water Reverse osmosis, which pumps water across a semipermeable membrane, produces RO water Water can also be purified by ultrafiltration, ultraviolet light, sterilization, or ozone treatment Reagent grade water Clinical and Laboratory Standards Institute Classified into 6 categories based on the specifications needed for its use rather than the method of purification or preparation Conventional Classification clinical laboratory reagent water (CLRW), special reagent water (SRW) – HPLC, Molecular diagnostics and spectrophotometric techniques instrument feed water water supplied by method manufacturer autoclave and wash water and commercially bottled purified water * water parameters include at least microbiological count, pH, resistivity, silicate, particulate matter, and organics Conventional Classification Type I most stringent requirements and generally suitable for routine laboratory use used for test methods requiring minimum interference, such as trace metal, iron, and enzyme analyses Conventional Classification ​ T​ ype II acceptable for most analytic requirements, including reagent, quality control, and standard preparation Conventional Classification Type III acceptable for glassware washing but not for analysis or reagent preparation Techniques of Water Purification Pre-filtration remove particulate matter filtration cartridges are composed of: glass; cotton; activated charcoal - which removes organic materials and chlorine glass or cotton filter – used for hard water containing calcium, iron, and other dissolved elements submicron filters (≤0.2 mm), which remove any substances larger than the filter’s pores, including bacteria may be better suited after distillation, deionization, or reverse osmosis treatment Techniques of Water Purification Distillation Water is boiled and vaporized The vapor rises and enters into the coil of a condenser, a glass tube that contains a glass coil Cool water surrounds this condensing coil, lowering the temperature of the water vapor. The water vapor returns to a liquid state, which is then collected Techniques of Water Purification Ion-exchange it is neither pure nor sterile deionized water is purified from previously treated water, such as prefiltered or distilled water uses either an anion or a cation exchange resin, followed by replacement of the removed particles with hydroxyl or hydrogen ions Techniques of Water Purification Exchange (or) Demineralization (or) Deionization Process. mineral ions are removed physical process which uses specially- manufactured ion exchange resins which bind to and filter out the mineral salts from water Techniques of Water Purification Reverse osmosis is a process that uses pressure to force water through a semipermeable membrane, producing water that reflects a filtered product of the original water Techniques of Water Purification Ultrafiltration and nanofiltration excellent in removing particulate matter, microorganisms, and any pyrogens or endotoxins Techniques of Water Purification Ultraviolet oxidation removes some trace organic material or sterilization processes (uses specific wavelengths), together with ozone treatment, can destroy bacteria but may leave behind residual products used after other purification processes have been used Testing procedures to determine the quality of reagent grade water Include measurements of: resistance, pH, colony counts (for assessing bacterial contamination) on selective and nonselective media for the detection of coliforms, chlorine, ammonia, nitrate or nitrite, iron, hardness, phosphate, sodium, silica, carbon dioxide, chemical oxygen demand (COD), and metal detection. document culture growth, pH and specific resistance on water Phases of Analytical Testing Phases of Analytical Testing What is Quality? Quality is the degree to which an object or entity (e.g., process, product, or service) satisfies a specified set of attributes or requirements Results Test is Sample Test is are ordered collection run reported Phases of Analytical Testing Quality Assurance Comprehensive set of policies, procedures, and practices that are followed to ensure that a laboratory’s results are reliable Note: Accuracy and Precision Includes record keeping, maintenance and calibration of equipment, proficiency testing, quality control, and training of personnel Accuracy Vs Precision Accuracy refers to how close a measurement is to the true or accepted value. Precision refers to how close measurements of the same item are to each other. RUN GLUCOSE RESULT RUN GLUCOSE RESULT NUMBER (mg/dL) NUMBER (mg/dL) 1 85 1 81 2 83 2 68 3 86 3 73 4 85 4 90 5 84 5 120 Phases of Analytical Testing  Phases of Analytical Testing Pre-analytical stage or pre-examination phase: The first of these stages is the pre-analytical phase, which may begin even before the specimen has reached the lab. This means that rigorous protocols must be in place to reduce the risk of errors in specimen handling and identification. Analytical phase or examination phase: The second phase is the analytical phase. This begins when the specimens have been logged into the lab. This phase is comprised of the lab diagnostic and testing procedures. Post-analytical phase or post-examination phase: The final, or post- analytical phase, involves reporting the final result. Results are sent to the required individual in a timely manner. Phases of Analytical Testing Pre-Analytical Phase Sample type Sample timing Sample handling Sample identification Phases of Analytical Testing Pre-Analytical Errors Arise before the samples are measured by laboratory professionals. Although most pre-analytical errors are discovered before the samples reach the lab, they can cause serious problems further down the line if they are not spotted. Phases of Analytical Testing Pre-Analytical Errors Patient Identification - This type of error includes missing or wrong patient information and may arise when a patient is not conscious at the time the sample is taken, or because the sample is needed very quickly. Patient identification errors may also be caused by improper or illegible specimen labeling. Phases of Analytical Testing Pre-Analytical Errors Specimen Collection- Sometimes errors can occur during specimen collection. Specimen collection errors might arise from patient conditions during collection—such as fragile veins. They can also occur if samples are taken at different points during the day, or when the patient is receiving laboratory medicines. Phases of Analytical Testing Quality Control To reduce pre-analytical error rates, all procedures should be standardized and automated whenever possible. By establishing a standardized system to recognize pre-analytical errors, many of these errors can be prevented. Implementing an automated system for identifying, storing, and tracking samples can eliminate errors at the front end. Doing this also cuts down the labor intensiveness of manual implementation. In this way, once an error has been detected, the system can be used to reject related samples. Phases of Analytical Testing Analytical Phase Issues with verification and quality control of performance specs Collaboration Errors Reagent mistakes Errors stemming from manual pipetting Interference from unidentified antibodies Mathematical errors Mistakes caused by staff fatigue Phases of Analytical Testing Quality Assurance To avoid these problems between test ordering and reporting test results, laboratories should commit to the following protocols: Implementation of manuals defining policy, process, and procedure Provision of clinician training and competency evaluation Implementation of a testing program for the clinician test menu Automation of instrument calibration and tracking Upkeep of records relating to the lab environment Phases of Analytical Testing Post-Analytical Phase Incorrect calculations Delayed turnaround time for results Results returned to the wrong individual Results are not reported Phases of Analytical Testing Quality Assurance Implement a bar code ID system: This not only prevents specimen misidentification and inaccurate labeling, but it also prevents the results from going to the wrong doctor or patient. Utilize automated transmission of reports: Digital transmission of reports ensures that results are being shared in a timely manner and that they are being sent to the person who needs them. Develop a troubleshooting plan: Take note of previous errors or close calls. Even more importantly, identify the source of the error, whether human or equipment. Once you have determined what happened, you can prevent a recurrence. Establish a standard for result reporting: If you set out clear protocols for your team of clinicians and it is in line with the healthcare facilities you are working with, you can reduce errors significantly throughout the total testing process. Phases of Analytical Testing There are numerous processes that occur within each of the three phases of testing. Some examples include: Thank you!