What does a capnography waveform that shows an obstructive pattern indicate?

A capnography waveform that shows an obstructive pattern indicates an obstruction in the airway. This pattern is characterized by a prolonged expiration phase, which means that the patient is having difficulty exhaling carbon dioxide effectively. In obstructive conditions, such as asthma or chronic obstructive pulmonary disease (COPD), the airways become narrowed or blocked, which results in an incomplete emptying of the lungs during expiration.

As a consequence, the waveform reflects elevated levels of carbon dioxide in the exhaled gas, demonstrating that the patient is not ventilating normally. Monitoring capnography in patients can thus help clinicians quickly identify and respond to obstructive airway issues, leading to timely interventions that can improve patient outcomes.

The other patterns observed in capnography, if they were present, would indicate different underlying issues, such as normal ventilation or a disconnection from the monitoring equipment, but they would not demonstrate the specific obstructive characteristics that are essential for diagnosing airway obstruction.