Which non-invasive method is used to monitor the oxygenation of a patient's hemoglobin?

• A. RSV
• B. Pulse Ox
• C. TB
• D. URI

Answer: (B)

Pulse oximetry is the non-invasive method used to monitor how well hemoglobin is oxygenated. It works by sending red and infrared light through a small sensor on a finger (or earlobe) and measuring the absorption differences between oxygenated and deoxygenated hemoglobin in pulsatile arterial blood. From this, it estimates the arterial oxygen saturation (SpO2) in real time, along with heart rate, without needing a blood draw. This is different from arterial blood gas, which gives PaO2 but requires invasive sampling.

The other options are disease names, not measurement tools, so they don’t describe a method for assessing oxygenation. Also, remember some factors can interfere with pulse oximetry readings (e.g., poor perfusion, nail polish, motion, or carbon monoxide exposure), but it remains the standard non-invasive monitor of oxygen saturation.