General occupational safety and health rules subdivision z toxic and hazardous substances
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- Attachment 2 Creatinine in Urine
- Principles of Procedure
- Compartment a Form Ingredient Quantity b
- For In Vitro Diagnostic Use. Mixing and Diluting
- Sample Cup Volumes (µL) Analyzer Standard
- Storage of Unprocessed Packs
- Antibiotic Peak serum level 7,8,9 Drug concentration
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All quality control samples should be plotted on the chart, and the charts should be checked for visual trends. If a quality control sample falls above or below the control limits for its pool, then corrective steps must be taken (see the section on corrective actions below). Once a laboratory’s program has been established, control limits should be updated every 2 months. The updated control limits should be calculated from the results of the last 100 quality control samples run for each pool. If 100 quality control samples from a pool have not been run at the time of the update, then the limits should be based on as many as have been run provided at least 20 quality control samples from each pool have been run over 20 different days. The trends that should be looked for on the control charts are: 1. 10 consecutive quality control samples falling above or below the mean; 2. 3 consecutive quality control samples falling more than 2σ from the mean (above or below the 2σ lines of the chart); or 3. the mean calculated to update the control limits falls more than 10% above or below the theoretical mean of 1.000. If any of these trends is observed, then all analysis must be stopped, and an investigation into the causes of the errors must begin. Before the analysis of compliance samples may resume, the inadequacies must be remedied and the control limits must be reestablished for that pool of an analyte. Reestablishment of control limits will entail running 20 sets of quality control samples over 20 days. Note that alternative procedures for defining internal quality control limits may also be acceptable. Limits may be based, for example, on proficiency testing, such as ±1 µg or 15% of the mean (whichever is greater). These should be clearly defined.
Corrective action is the term used to describe the identification and remediation of errors occurring within an analysis. Corrective action is necessary whenever the result of the analysis of any quality control sample falls outside of the established control limits. The steps involved may include simple things like checking calculations of basic instrument maintenance, or it may involve more complicated actions like major instrument repair. Whatever the source of error, it must be identified and corrected (and a Corrective Action Report (CAR) must be completed. CARs should be kept on file by the laboratory. Attachment 2 Creatinine in Urine (JAFFE PROCEDURE). Intended Use: The CREA pack is used in the Du Pont ACA® discrete clinical analyzer to quantitatively measure creatinine in serum and urine. Summary: The CREA method employs a modification of the kinetic Jaffe reaction reported by Larsen. This method has been reported to be less susceptible than conventional methods to interference from noncreatinine, Jaffe-positive compounds.1 A split sample comparison between the CREA method and a conventional Jaffe procedure on Autoanalyzer® showed a good correlation. (See Specific Performance Characteristics). * NOTE: Numbered subscripts refer to the bibliography and lettered subscripts refer to footnotes. Autoanalyzer,® is a registered trademark of Technicon Corp., Tarrytown, NY. Principles of Procedure: In the presence of a strong base such as NaOH, picrate reacts with creatinine to form a red chromophore. The rate of increasing absorbance at 510 nm due to the formation of this chromophore during a 17.07-second measurement period is directly proportional to the creatinine concentration in the sample. Creatinine + Picrate NaOH Red chromophore (absorbs at 510 nm)
Used Packs Contain Human Body Fluids; Handle With Appropriate Care. Precautions: Compartment #6 contains 75 µL of 10 N NaOH; Avoid Contact; Skin Irritant; Rinse Contacted Area With Water. Comply With OSHA’s Bloodborne Pathogens Standard While Handling Biological Samples (29 CFR 1910.1039). For numerical footnotes, see bibliography on page 167. For In Vitro Diagnostic Use. Mixing and Diluting: Mixing and diluting are automatically performed by the ACA® discrete clinical analyzer. The sample cup must contain sufficient quantity to accommodate the sample volume plus the “dead volume”; precise cup filling is not required.
Storage of Unprocessed Packs: Store at 2-8 °C. Do not freeze. Do not expose to temperatures above 35 °C or to direct sunlight. Expiration: Refer to EXPIRATION DATE on the tray label. Specimen Collection: Serum or urine can be collected and stored by normal procedures.2 Known Interfering Substances:3 • Serum Protein Influence. Serum protein levels exert a direct influence on the CREA assay. The following should be taken into account when this method is used for urine samples and when it is calibrated: Aqueous creatinine standards or urine specimens will give CREA results depressed by approximately 0.7 mg/dL [62 µmol/L]1 and will be less precise than samples containing more than 3 g/dL [30 g/L] protein. All urine specimens should be diluted with an albumin solution to give a final protein concentration of at least 3 g/dL [30 g/L]. Du Pont Enzyme Diluent (Cat. #790035-901) may be used for this purpose. • High concentration of endrogenous bilirubin (>20 mg/dL [>342 µmol/L]) will give depressed CREA results (average depression 0.8 mg/dL [71 µmol/L]). 4 • Grossly hemolyzed (hemoglobin >100 mg/dL [>62 µmol/L]) or visibly lipemic specimens may cause falsely elevated CREA results. 5,6 • The following cephalosporin antibiotics do not interfere with the CREA method when present at the concentrations indicated. Systematic inaccuracies (bias) due to these substances are less than or equal to 0.1 mg/dL [8.84 µmol/L] at CREA concentrations of approximately 1 mg/dL [88 µmol/L].
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