What does a capnography waveform indicate when it shows normal ventilation?

A capnography waveform that indicates normal ventilation displays a consistent and recognizable pattern. This pattern reflects the levels of carbon dioxide (CO2) being exhaled and provides crucial information about the patient’s respiratory status. When the waveform appears normal, it signifies that the alveoli are effectively participating in gas exchange, allowing for the appropriate uptake of oxygen and the elimination of carbon dioxide. This suggests that the ventilation process is functioning properly, as CO2 levels correspond with what is expected during normal respiratory physiology.

Normal alveolar ventilation shows a shape that typically resembles a rectangular waveform, with distinct phases indicating inhalation and exhalation without irregularities, which means that the air exchange within the lungs is occurring as it should. Additionally, a normal capnography reading suggests that there are no significant obstructions or abnormalities in the airway that might impede proper ventilation. This makes it clear that overall lung function and metabolic processes are stable and effectively matching the body's needs.