What arterial blood gas values are indicative of hypoxemic respiratory failure in a client with Guillain-Barré syndrome?

The correct answer highlights arterial blood gas values that indicate hypoxemic respiratory failure, specifically a significantly low partial pressure of oxygen (PaO2). In a client with Guillain-Barré syndrome, which can lead to respiratory muscle weakness and impaired gas exchange, a PaO2 of 50 mm Hg indicates severe hypoxemia. This level of oxygen saturation is critically low and reflects that the body is not adequately oxygenating the blood, a hallmark of hypoxemic respiratory failure.

The PaCO2 value of 40 mm Hg is within the normal range, which suggests that while the body is not effectively oxygenating, it hasn’t yet retained significant carbon dioxide to create hypercapnia (an excess of carbon dioxide in the bloodstream). This distinction is crucial because hypoxemic respiratory failure primarily manifests as low oxygen levels, while hypercapnic failure would show elevated CO2 levels.

In contrast, the other provided values demonstrate either normal oxygenation or only mild deviation from normal, indicating that those patients are not in a state of hypoxemic respiratory failure. For example, a PaO2 of 75 mm Hg is within the acceptable range, indicating adequate oxygenation, while a PaO2 of 90 mm Hg and another at