During evaluation, saO2 is 93% with nasal oxygen dislodged. After readjusting the nasal cannula, saO2 increases to 95%. Which statement best describes this?

• A. The oxygen saturation is unreliable.
• B. The patient requires intubation.
• C. The oxygen saturation remains low.
• D. The readjustment improved oxygen saturation.

Answer: (D)

The key idea is that oxygen delivery depends on the cannula remaining properly in place. When the nasal cannula is dislodged, much of the supplemental oxygen isn’t getting delivered to the patient, so the measured oxygen saturation can fall. Once the cannula is readjusted and fits correctly, more of the prescribed oxygen reaches the lungs, improving the saturation—here from 93% to 95%. That change shows the intervention directly increased oxygen delivery rather than implying the measurement is unreliable or that the patient needs more extreme measures. A saturation of 95% is generally considered adequate for many adults on supplemental oxygen, so this improvement reflects effective adjustment of the delivery device rather than a need for escalation like intubation.