What should a respiratory therapist do if a blood gas analyzer shows one point outside the 4 SD range?

• A. Classify the data point as an outlier and continue analysis on blood samples
• B. Do not use the blood gas analyzer
• C. Replace the blood gas analyzer
• D. Call the medical director

Answer: (A)

The correct approach when a blood gas analyzer shows a point outside of the four standard deviation range is to classify that data point as an outlier and continue analyzing the blood samples. This practice is rooted in statistical quality control, which allows for identifying potential errors while not discarding valid test results unnecessarily.

In medical diagnostics, consistently reviewing and acknowledging outliers is crucial. An outlier can occur due to a number of reasons, including patient-specific factors or temporary issues with the analyzer. Classifying it as an outlier indicates that the value should be investigated but does not automatically invalidate the entire testing process. More analysis can provide context, and subsequent measurements can validate or invalidate the initial outlier.

In contrast, disregarding the analyzer entirely, replacing it, or escalating the situation to the medical director without further investigation would not be necessary steps at this immediate stage of quality control and could hinder the timely analysis and management of patient care. Thus, assessing the outlier while continuing routine processes is both wise and efficient.