1What is a cough?
Coughing could be either voluntary or involuntary. As one of the most common symptoms, the protective reflex is part of your body’s mechanism to get rid of irritants or pollutants in your throat or airway such as dust, pollen, microbes, smoke, and fluids. In most textbooks, a cough has three phases:
- Inspiratory phase: inhale air into lungs to generate an effective cough
- Compressive phase: close glottis to increase intrathoracic pressure
- Expulsive phase: open glottis to rapidly release airflow in lungs and accomplish the cough
In the expulsive phase, there is often accompanied by a distinctive sound. [1]
