What does it mean if you inhale and feel a puff of air come out your mouth automatically?

Inhaling and feeling a puff of air come out of your mouth automatically can be a sign of a fistula, which is an abnormal connection between two organs or body cavities. In this case, it could be a fistula between your lungs and your mouth. This type of fistula is rare but can occur due to various causes, such as trauma or infection. If you experience this symptom, it's important to see a doctor for evaluation and appropriate treatment.