A recently introduced blood gas/electrolyte analyzer (SenDx 100((R)),
renamed ABL70) intended for point-of-care, near-patient, or stat
laboratory use was evaluated simultaneously in four different institutions
and compared with three different laboratory bench analyzers with respect
to imprecision, inaccuracy (assessed by tonometry), and patient-sample
analyses. The analyzer is equipped with a sensor cassette and a reagent
cartridge for 50, 100, or 200 analyses and 100 or more traditional
quality-control measurements. One analysis requires 170 microL of whole
blood and takes <90 s. Statistically, the instrument performed somewhat
better (lower CVs) for PO2 and potassium and somewhat worse for pH, PCO2,
and ionized calcium than the respective comparison analyzers. However, the
overall performance (in terms of CV and accuracy) was satisfactory in
terms of clinical (e.g., CLIA '88) goals in all institutions. The mean
difference and the CV of that difference in some 400 patient-sample
comparisons were as follows: 0.010 (+/- 0.002%) for pH, -0.65 mmHg (+/-
4%) for PCO2, -0.49 mmHg (+/- 6%) for Po2, 0.44 mmol/L (+/- 1.2%) for
sodium, -0.013 mmol/L (+/- 2.9%) for potassium, -0.016 mmol/L (+/- 2.6%)
for ionized calcium, and -0.016 L/L (+/- 7. 1%) for the hematocrit. Its
acceptable analytical performance and ease of operation make the SenDx 100
suitable for the analysis of blood gases and electrolytes