Bronchoscopy is used for investigating symptoms, assessing lung infiltrates and masses, staging lung cancer, obtaining samples for diagnosis, and treating conditions like infections, tumors and collapsed airways. It involves inserting a flexible tube with a camera through the mouth or nose into the lungs. Risks include low oxygen, bleeding, collapsed lung, heart problems and death. Patients are prepared with scans, tests and fasting beforehand. Sedation is usually used and monitoring during and after the procedure is important. Informed consent discusses the patient's condition, procedure details, risks and alternatives.