HemoCue beta-glucose photometer evaluated for use in a neonatal intensive care unit.

We evaluated the HemoCue beta-Glucose Photometer system for use in our neonatal intensive care unit by assaying 178 heparinized whole-blood samples obtained by heel stick. The required sample size is 5 microL. Plasma glucose was analysed by a glucose oxidase/oxygen electrode methodology. Across the glucose range of 1.28-21.87 mmol/L, the regression slope was 0.976 (r = 0.976, Sy/x = 0.475). For samples with hematocrit < or = 0.30, the regression slope was 0.981 (r = 0.950, Sy/x = 0.415); for hematocrit of 0.31-0.49, the regression slope was 0.984 (r = 0.972, Sy/x = 0.508); and for hematocrit > or = 0.50, the regression slope was 0.959 (r = 0.988, Sy/x = 0.394). Human whole blood, bovine whole blood, and bovine serum-based quality-control materials were studied. Except for assays of the low-concentration human control material, the total CV was < 3.5%. The accuracy and precision of the HemoCue system were comparable with those of conventional laboratory instrumentation.

Analytical evaluation of i-STAT Portable Clinical Analyzer and use by nonlaboratory health-care professionals.

We evaluated the performance of the i-STAT Portable Clinical Analyzer, a hand-held instrument that, with its current cartridge, analyzes for electrolytes, urea nitrogen, glucose, and hematocrit in approximately 60 microL of whole blood in approximately 90 s. Accuracy, imprecision, and linearity studies were performed with aqueous controls and standards and by split-sample analysis. Intrarun imprecision (CV) ranged from 0.34% to 3.97%. Total imprecision over a 2-month period ranged from 0.42% to 4.83%, with urea nitrogen and glucose analyses generating the higher values. Patients' results from the Portable Clinical Analyzer correlated well with those obtained for whole blood or plasma by the Nova Stat Profile 5, the Beckman Synchron CX3, or the Technicon H1 Hematology Analyzer, with Sylx values < 0.2 mmol/L for potassium; < 1.5 mmol/L for sodium, glucose, and urea nitrogen; < 2.4 mmol/L for chloride, and < 2.4% for hematocrit. We also ascertained imprecision and accuracy of the system placed in a cardiothoracic intensive-care unit and operated by nurses. There were no significant differences in either the imprecision or accuracy of the system in this setting. We conclude that operator technique is not a factor in the analytical performance of the system and that it can be used by nonlaboratorians with a high degree of confidence that reliable results will be obtained.