Dr. Meghan Orris Keaton, MD

Asthma is a chronic lung disease where the tissue and airways of the lungs become extremely sensitive to certain substances. When these substances are breathed in, the lungs become inflamed. The muscles around the airways tighten and squeeze the lungs, and passages within the lungs swell and tighten. The airways themselves produce mucus, which further clogs the tightened, swollen airways. A person having an asthma attack finds it very difficult to breathe, and a severe attack can even be fatal.

Asthma affects people of all ages, but people with asthma are most often diagnosed as children. Symptoms can include wheezing, a tight feeling in the chest, shortness of breath, and coughing. Some people have mild symptoms all the time, and some people have no symptoms at all, but everyone with asthma is susceptible to occasional severe attacks or flare-ups of symptoms when they are exposed to triggers. Triggers vary widely but can include:

• Allergens (dust mites, pet fur, mold, pollen, grass)
• Irritants (smoke, pollution, dust, chemicals)
• Viral infections
• Physical activity, especially outdoors
• Certain medications or chemicals in foods (aspirin, sulfites)

Bronchoscopy is a procedure in which a thin tube with a camera, called a bronchoscope, is inserted in the mouth or nose and slowly advanced to the lungs. This allows doctors to see the respiratory tract, which includes the throat, larynx (voice box), trachea (windpipe), bronchi (airways), and lungs. Doctors may recommend those who have or show signs of lung problems - for example, lung cancer or difficulty breathing - to undergo a bronchoscopy.

In performing a diagnostic bronchoscopy, doctors may only wish to visualize the respiratory tract, or doctors may also collect samples of tissue or fluid. The samples can help diagnose patients' conditions or, if patients have cancer, they can be used for staging purposes. One method for sample collection is bronchoalveolar lavage. In a bronchoalveolar lavage, doctors inject saline (salt water) through the bronchoscope and then suction it out of the airways. The washout collected is tested for lung disorders. Doctors can also insert a biopsy tool to collect tissue or mucus samples. The following are biopsies that can be performed by bronchoscopy:

• Brush biopsy, which uses a brush to collect samples.
• Endobronchial biopsy, which uses the bronchoscope to guide forceps to sample lung tissue.
• Transbronchial biopsy, which uses forceps and image guidance - such as X-rays, CT scans, or fluoroscopy - to sample lung tissue.
• Transbronchial fine needle aspiration (TBNA), which uses a small needle to take samples of the lymph nodes or lungs.