A 150 lb,62 year old man had a chronic productive cough, exertional dyspnea, mild cyanosis, and marked slowing of forced expiration. His pulmonary function and laboratory tests follow: Frequency 16 breaths/min alveolar ventilation 4.2 L/min (Assume 150 ml anatomical dead space) vital capacity 2.2 L functional residual capacity 4.0 L total lung capacity 5.2 L maximum inspiratory flow rate 250 L/min maximum expiratory flow rate 20 L/min PaO2 62 mm Hg PaCO2 39 mm Hg Pulmonary function tests after bronchodilator therapy: frequency 16 breaths/min alveolar ventilation 4.35 L/min VC 2.4 L FRC 4.0 L TLC 5.2 L Max inspiratory flow rate 250 L/min max expiratory flow rate 23 L/min PaO2 62 mm Hg PaCO2 38 mm Hg Questions: 1. What is the disorder this man has? 2. Is this primarily a restrictive or obstructive disorder? Why? 3. Why is the bronchodilator therapy ineffective in this man? 4. What causes hypoxemia? 5. Calculate the residual volume (RV) for this person before and after the bronchodilator therapy. 6. What is the cause of this altered RV? 7. Calculate the tidal volume (TV) for this man before and after the bronchodilator therapy. 8. Is each TV normal or altered? 9. Calculate the minute ventilation for this person before and after the bronchiodialator therapy? 10. Is each minute ventilation normal or altered?