What does a capnograph measure?

A capnograph is an important tool used in various medical settings, particularly in anesthesia and respiratory care. It specifically measures the concentration of carbon dioxide (CO2) in the air that a patient exhales. This measurement provides critical information about the patient’s ventilatory status and metabolic function.

Monitoring CO2 levels through capnography is crucial because it helps healthcare providers assess the effectiveness of ventilation and can indicate respiratory distress or failure. For example, an increase in exhaled CO2 could indicate inadequate ventilation or potential respiratory issues, while low levels might suggest hyperventilation.

Other choices, while related to physiological measurements, do not accurately describe the function of a capnograph. Heart rate monitoring is done through different types of monitors, oxygen levels in the blood are measured using pulse oximetry, and body pH levels are typically assessed through blood gas analysis rather than capnography. Therefore, the correct answer highlights the specialized role of the capnograph in evaluating CO2 levels in expired air, which is essential for patient management during procedures requiring sedation or anesthesia.