This test is performed while a patient sedated by a pediatric pulmonologist and is not available as part of a clinic visit. A bronchoscopy consists of inserting a long, thin tube (usually through the nose) through the upper airway into the lungs. The physician can look at the surface of the lungs and take sputum specimens. This test may help find an infection or other lung problem. A CF patient may never need a bronchoscopy. It is performed only when a problem persists that cannot be identified by other means.