Final answer:
Exposure of blood gas analysis specimens to ambient air can lead to altered partial pressures of oxygen and carbon dioxide in the sample, causing inaccurate results.
Step-by-step explanation:
When specimens for blood gas analysis are exposed to ambient air, the partial pressures of gases in the sample can change, leading to inaccurate measurements of blood gas concentrations. Specifically, the oxygen in the ambient air can diffuse into the blood specimen, potentially causing a false elevation in the measured partial pressure of oxygen (PaO2). Correspondingly, carbon dioxide (CO2) may diffuse out into the ambient air, which might result in an erroneously low partial pressure of carbon dioxide (PaCO2).
Similarly, if nitrogen in the air enters the specimen, it can cause an apparent rise in nitrogen levels. This is because gas exchange, including the transport of oxygen and carbon dioxide, is influenced by the partial pressures of those gases. Hence, to maintain accuracy, it is crucial to minimize or eliminate the specimen's exposure to air.