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Robert W Burnett

Publications and source records attributed to Robert W Burnett.

6 recordsLinked to original sources
PubMed2006

Recommendation for measuring and reporting chloride by ISEs in undiluted serum, plasma or blood.

The proposed recommendation for measuring and reporting chloride in undiluted plasma or blood by ion-selective electrodes (ISEs) will provide results that are identical to chloride concentrations measured by coulometry for standardized normal plasma or blood samples. It is applicable to all current ISEs dedicated to chloride measurement in undiluted samples that meet the requirements. However, in samples with reduced water concentration, results by coulometry are lower than by ion-selective electrode due to volume displacement. The quantity measured by this standardized ISE procedure is called the ionized chloride concentration. It may be clinically more relevant than the chloride concentration as determined by coulometry, photometry or by ISE after dilution of the sample.

Analysis of Variance↗
PubMed2006

Approved IFCC recommendation on reporting results for blood glucose: International Federation of Clinical Chemistry and Laboratory Medicine Scientific Division, Working Group on Selective Electrodes and Point-of-Care Testing (IFCC-SD-WG-SEPOCT).

In current clinical practice, plasma and blood glucose are used interchangeably with a consequent risk of clinical misinterpretation. In human blood, glucose is distributed, like water, between erythrocytes and plasma. The molality of glucose (amount of glucose per unit water mass) is the same throughout the sample, but the concentration is higher in plasma, because the concentration of water and therefore glucose is higher in plasma than in erythrocytes. Different devices for the measurement of glucose may detect and report fundamentally different quantities. Different water concentrations in the calibrator, plasma, and erythrocyte fluid can explain some of the differences. Results for glucose measurements depend on the sample type and on whether the method requires sample dilution or uses biosensors in undiluted samples. If the results are mixed up or used indiscriminately, the differences may exceed the maximum allowable error for glucose determinations for diagnosing and monitoring diabetes mellitus, thus complicating patient treatment. The goal of the International Federation of Clinical Chemistry and Laboratory Medicine, Scientific Division, Working Group on Selective Electrodes and Point of Care Testing (IFCC-SD-WG-SEPOCT) is to reach a global consensus on reporting results. The document recommends reporting the concentration of glucose in plasma (in the unit mmol/L), irrespective of sample type or measurement technique. A constant factor of 1.11 is used to convert concentration in whole blood to the equivalent concentration in plasma. The conversion will provide harmonized results, facilitating the classification and care of patients and leading to fewer therapeutic misjudgments.

Biosensing Techniques↗
PubMed2005

Approved IFCC recommendation on reporting results for blood glucose (abbreviated).

In current clinical practice, plasma and blood glucose are used interchangeably with a consequent risk of clinical misinterpretation. In human blood, glucose, like water, is distributed between erythrocytes and plasma. The molality of glucose (amount of glucose per unit of water mass) is the same throughout the sample, but the concentration is higher in plasma because the concentration of water and, therefore, glucose is higher in plasma than in erythrocytes. Different devices for the measurement of glucose may detect and report fundamentally different quantities. Different water concentrations in calibrators, plasma, and erythrocyte fluid can explain some of the differences. Results of glucose measurements depend on sample type and on whether methods require sample dilution or use biosensors in undiluted samples. If the results are mixed up or used indiscriminately, the differences may exceed the maximum allowable error of glucose determinations for diagnosing and monitoring diabetes mellitus, and complicate the treatment. The goal of the IFCC Scientific Division Working Group on Selective Electrodes and Point of Care Testing (IFCC-SD, WG-SEPOCT) is to reach a global consensus on reporting results. The document recommends reporting the concentration of glucose in plasma (with the unit mmol/L), irrespective of sample type or measurement technique. A constant factor of 1.11 is used to convert concentration in whole blood to the equivalent concentration in the pertinent plasma. The conversion will provide harmonized results, facilitating the classification and care of patients and leading to fewer therapeutic misjudgments.

Blood Chemical Analysis↗
PubMed2005

Guidelines for sampling, measuring and reporting ionized magnesium in undiluted serum, plasma or blood: International Federation of Clinical Chemistry and Laboratory Medicine (IFCC): IFCC Scientific Division, Committee on Point of Care Testing.

All analyzers with ion-selective electrodes for ionized magnesium (iMg) should yield comparable and unbiased results. The prerequisite to achieve this goal is to reach consensus on sampling, measurement and reporting. The recommended guidelines for sampling, measurement and reporting iMg in plasma ("plasma" refers to circulating plasma and the forms in which it is sampled: the plasma phase of anticoagulated whole blood, plasma separated from blood cells, or serum) or blood, referring to the substance concentration of iMg in the calibrants, will provide results for iMg that are approximately 3% greater than its true concentration, and 4% less than its true molality. Binding of magnesium to proteins and ligands in plasma and blood is pH-dependent. Therefore, pH should be simultaneously measured to allow adjustment of iMg concentration to pH 7.4. The substance concentration of iMg may be physiologically and consequently clinically more relevant than the substance concentration of total magnesium.

Blood Chemical Analysis↗