Which condition can cause the high-pressure alarm to sound on a mechanical ventilator?

The high-pressure alarm on a mechanical ventilator is designed to alert healthcare providers to potential issues that may obstruct airflow or make ventilation difficult for the patient. Coughing can cause a temporary increase in intrathoracic pressure, resulting in resistance to airflow and triggering the high-pressure alarm. When a patient coughs, the increased effort to breathe combined with closed airways or equipment resistance can lead to elevated pressure readings that the ventilator monitors.

Understanding the mechanics of ventilation helps clarify the other options. Kinked tubing can also cause increased pressure and might be a valid cause for the high-pressure alarm, but the cough is a direct and frequent trigger seen in patients actively using the ventilator. A disconnected tube would typically lead to a loss of pressure and activate a low-pressure alarm instead, as it would create insufficient airflow to register high-pressure readings. Low oxygen levels may lead to alarms related to oxygen delivery but would not directly influence mechanical pressures to raise the high-pressure alarm. Therefore, coughing stands out as a clear and common reason for the alarm activation.