During a generalized anesthesia evaluation, which parameter indicates hypoxemia?

The parameter indicating hypoxemia is a saturation of oxygen in the blood, represented by the value of SaO2. A SaO2 of 88% signifies that only 88% of hemoglobin is saturated with oxygen, which is below the normal range of 95-100%. This low level of oxygen saturation clearly indicates the patient is experiencing hypoxemia, as healthy individuals typically maintain at least 90% saturation.

Other parameters, while important for assessing overall respiratory function, do not directly indicate hypoxemia. The fraction of inspired oxygen (FiO2) measures the oxygen concentration in the air being inhaled, and a value of 1 indicates 100% oxygen, which would not suggest hypoxemia. The partial pressure of carbon dioxide (PaCO2) of 42 is within normal limits (typically 35-45 mmHg) and doesn't address oxygen transport or levels within the blood. End-tidal carbon dioxide (ETCO2) of 33 indicates the amount of carbon dioxide exhaled and is more reflective of ventilation than oxygenation status. Therefore, a SaO2 of 88% is the clear indicator of hypoxemia in this evaluation.