Arterial Blood Evaluation (Effect of pO2: Performance with Arterial Specimens)

An arterial specimen study was performed at a hospital site. Ascensia™ CONTOUR ™ results from arterial samples were compared to the site blood glucose method. The glucose concentration of the samples ranged from 3.1 to 24.0 mmol/L, with an average of 8.5 mmol/L. The sample hematocrit range was 22 to 58%, with an average of 39%. The pO2 values ranged from 43 to 205 mm Hg, with an average of 104 mm Hg. The reference range for arterial pO2 is 83 to 108 mm Hg (11.1 to 14.4 kPa)1. Mean biases were –2.9% at pO2 concentrations <83 mm Hg (n = 33, Mean pO2 = 71 mm Hg), –2.5% at pO2 concentrations between 83 to 108 mm Hg (n = 40, Mean pO2 = 94 mm Hg), and –0.8% at pO2 concentrations >108 mm Hg (n = 38, Mean pO2 = 143 mm Hg). Two samples had glucose concentrations <4.2 mmol/L and the bias was calculated as an absolute difference rather than a percentage. These samples had biases of –0.06 mmol/L and –0.44 mmol/L; pO2 values were 80 and 112 mm Hg, respectively.

1Carl Burtis and Edward Ashwood (eds.): Tietz Textbook of Clinical Chemistry. 3rd Ed., W.B. Saunders Co. Philadelphia, PA. 1999, p. 1827.

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