1. Case Study 1 A 53-year-old white male presents for annual visit. Although he quit 10 years ago he is a previous cigarette smoker with a 20 pack-year history. During the past 12 months, he has had 3 episodes of bronchitis. His history of tobacco use and recent episodes of acute bronchitis lead you to perform spirometry.

2. Volume IC Pulmonary spirometry. Lung volumes in Liters Capacities FRC RV TLC VC ERV TV IRV 1 0 5 2 6 4 3 Lung Volume

3. 0 1 2 3 4 5 6 7 FEV1 IC FVC 1 second FVC FEV 1 5 4 FVC 4 5 80% or 0.8 Lung volume (liter)

4. 0 1 2 3 4 5 6 7 FEV1 IC FVC 1 second Lung volume (liter)

5. 0 1 2 3 4 5 6 7 FEV 1 IC FVC 1 secon d Lung volume (liter)

6. 0 1 2 3 4 5 6 7 FEV 1 IC FVC 1 seco nd Lung volume (liter)

7. 0 1 2 3 4 5 6 7 FEV 1 IC FVC 1 seco nd Lung volume (liter) 0 1 2 3 4 5 6 7 FEV 1 IC FVC 1 seco nd Lung volume (liter) 0 1 2 3 4 5 6 7 FEV 1 IC FVC 1 seco nd Lung volume (liter) OLD Normal RLD FVC FEV 1 FVC FEV 1 FVC FEV 1 FVC 4 3.5 4 2 50% 5 4 80% 86%

8. Obstructive Lung Disease FEV 1FVCRVFRCTLC Restrictive Lung Disease FEV1 FVC

9. Inspiration RV 0 TLV Lung Volume (liters) Expiration

10. RV VOLUME FLOW Expiration Inspiration A B C D E TLC

11. Forced expiratory flow –Volume loop Normal Lung Volume (liters) Expiratory Flow Rate (liters/sec) 65 4 32 1 Obstructive Restrictive

12. Relaxation pressure-volume curve of the lung, chest wall, and respiratory system 0 FRC Chest Wall Lung Chest wall and lung 0 Pressure (cm H2O) 2 4 -2040 6 20-10 Vital capacity (L) (Respiratory system) TLC VTVT 3010

13. Case 2 A 24-year-old pregnant woman presented to the hospital in preterm labor and subsequently delivered a premature infant at only 27 weeks gestation (normal term pregnancy is 37-42 weeks). After the delivery, the infant cried, but it subsequently began to grunt and showed signs of hypoxia despite oxygen supplementation. The baby immediately was intubated by endotracheal tube and given surfactant down the endotracheal tube. The baby’s hypoxia resolved, and he was transferred to the neonatal intensive care unit for further stabilization.

14. What is the role of surfactant in the lung? Reduces surface tension.

15. Where is the major site of airway resistance? Medium-sized bronchi.

16. How does stimulation of the parasympathetic system affect airway resistance? Increased airway resistance because of smooth muscle constriction in bronchi.