Primarily diagnose during the first day of Acute Cough [once the FB reaches the lung, there’s no more cough until / unless a pneumonia develops.
Risk factors: Young Child, person with compromised gag reflex. Symptoms commonly begin while eating.
Physical Exam: Respiratory Distress and / or Stridor (call 911).
For pneumonias that recur in the exact same location, consider presence of FB (or tumor). Diagnose by CT / bronchoscopy / fluoroscopy.
See posting Acute Cough – 1.