SaO2na

SaO2na is a data label occasionally encountered in clinical databases and electronic health record exports to indicate that arterial oxygen saturation (SaO2) data are not available for a given observation. The term is not a recognized clinical metric; rather, it reflects data missingness or noncollection status in a dataset.

In practice, SaO2 denotes the fraction of hemoglobin saturated with oxygen in arterial blood, typically reported as a percentage and measured by arterial blood gas analysis or co-oximetry, whereas SpO2 from pulse oximetry provides a noninvasive estimate. Normal SaO2 values in healthy adults at sea level are about 94-100%, with SpO2 typically aligning within one or two percentage points of SaO2 when tissues are adequately perfused.

When a dataset marks SaO2na, researchers often address missing data via imputation, exclusion, or sensitivity analyses. The presence of SaO2na can affect assessments of oxygenation status, perioperative risk, and outcome correlations in retrospective studies, particularly if missingness is not random.

In data dictionaries or interoperability standards, similar suffixes or codes may appear to flag missing vital signs; consistent documentation is essential for accurate interpretation. If you encounter SaO2na in a specific application, consult the data dictionary or the source's metadata to confirm the intended meaning.