What monitoring method provides real-time information about a patient’s oxygen saturation?

• A. Electrocardiography
• B. Thermography
• C. Pulse Oximetry
• D. Spirometry

Answer: (C)

Pulse oximetry provides real-time information about a patient’s oxygen saturation. It uses a small sensor placed on a fingertip, earlobe, or toe to continuously emit red and infrared light and measure how much is absorbed by oxygenated versus deoxygenated hemoglobin. The device converts that data into an SpO2 reading and a pulse rate, updating constantly so you can see trends and detect desaturation immediately. This noninvasive method is specifically designed to monitor oxygenation as it changes.

The other options measure different body signals: electrocardiography tracks the heart’s electrical activity, not oxygen saturation; thermography maps skin temperatures rather than blood oxygen levels; and spirometry measures lung volumes and airflow, not how much oxygen is bound to hemoglobin.