This MDL is devoted to a patient with "obstructive" lung disease. It will test your understanding of pulmonary mechanics and gas exchange in this disorder.


A 65 years old former garage mechanic presents with a chief complaint of increased shortness of breath and a change in the quantity and color of his sputum for the past week. The sputum is usually scant and clear. However, recently it has become yellow and continues all day. He has had trouble raising sputum in the past year. He has become progressively short of breath over the last five years. He is now dyspneic at rest. He denies asthma, childhood respiratory problems, allergies and any occupational exposures.

Physical Examination