Assessing the ABL 500 blood gas analyser.

Area of Science:

• Clinical Chemistry
• Medical Diagnostics
• Biomedical Engineering

Background:

• The Radiometer ABL 500 is a blood gas analyser with cordless electrodes and no humidifier for calibration gases.
• Evaluating analytical performance is crucial for diagnostic instruments.

Purpose of the Study:

• To assess the analytical performance of the ABL 500 blood gas analyser.
• To investigate the accuracy of oxygen partial pressure (pO2) measurements using different tonometry methods.

Main Methods:

• Comparison of ABL 500 pO2 values with film and bubble tonometry.
• Evaluation of within-run and day-to-day precision for pO2 and pCO2.
• Inter-instrument comparison with the Ciba Corning 178 analyser.

Main Results:

• Acceptable imprecision was demonstrated for all measured parameters.
• Within-run coefficients of variation (CV) were ≤0.37% for pO2 and ≤0.52% for pCO2.
• Day-to-day CV was 1.76% for both pO2 and pCO2.
• A slight overestimation of pO2 (2.2-3.4% at 600 mmHg) was observed above 150 mmHg.

Conclusions:

• The ABL 500 demonstrates acceptable precision for blood gas analysis.
• Minor discrepancies in pO2 accuracy above 150 mmHg warrant further investigation.
• Accurate pO2 assessment is critical for evaluating blood gas analysers.