A pulse oximeter reading of 88% on room air indicates what?

• A. Normal oxygenation.
• B. Hyperoxia.
• C. Dehydration.
• D. Hypoxemia; needs supplemental oxygen and assessment.

Answer: (D)

Pulse oximetry estimates how much oxygen the arterial blood is carrying as a percentage (SpO2). Normal on room air is typically about 95–100%. An 88% reading indicates hypoxemia, meaning there isn’t enough oxygen in the blood to meet the body’s needs. This is a medical concern that calls for starting supplemental oxygen and a quick assessment to identify the cause (such as pneumonia, a COPD flare, pulmonary edema, or other respiratory problems) and to guide treatment. Dehydration would not inherently lower SpO2, and a low reading is not hyperoxia (which would show a high saturation). Remember that SpO2 is only one clue; an ABG may be needed to evaluate PaO2 and acid-base status, and readings can be affected by factors like poor perfusion.