Which of the following describes capnometry?

Capnometry refers specifically to the measurement of carbon dioxide (CO2) levels in exhaled gases. This technique is fundamental in respiratory care and provides crucial information about ventilation and metabolic processes. By analyzing the concentration of CO2 in the breath, healthcare professionals can assess a patient's respiratory function and detect conditions such as hypoventilation or hyperventilation.

This measurement is typically performed using a capnometer, which displays the CO2 levels in real-time, often as a waveform graph called capnography. Clinicians utilize this data to monitor patients during procedures requiring sedation or anesthesia, as well as in critical care settings to ensure adequate ventilation.

In contrast, the other options focus on different types of measurements: assessing oxygen levels is related to pulse oximetry, measuring heart rhythm pertains to electrocardiograms (ECGs), and blood glucose measurement is relevant in diabetes management. Each of these tests serves a unique purpose in patient care, but they are not related to capnometry's focus on carbon dioxide.