A 55-year-old male presents to your office for assessment of a chronic cough. He states he has “been coughing for the last ten years”, but the cough is becoming more bothersome lately. The cough is productive of sputum that is usually mucoid; occasionally it becomes purulent. His significant past history is a 35-year history of smoking 2 packs of cigarettes/day. On examination, he is obese (280 pounds). He wheezes while he talks. On auscultation, adventitious breath sounds are heard in all lobes. His chest x-ray reveals increased markings at the lung bases.