Case study

CASE STUDY

A 155lb; 60- years 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 15 breaths/ min

Alveolar ventilation 4.1 L/min

Vital Capacity (VC) 2.2L

Functional Lung residual capacity (FRC) 4.0 L

Total Lung Capacity (TLC) 5.2 L

Maximum inspiratory flow rate 252 L/min

Maximum expiratory flow rate 21 L/ min

Pa o2 63MM Hg

PaCo2 38 MM Hg

Pulmonary function tests after bronchodilator therapy:

Frequency 15 breaths/ min

Alveolar ventilation 4.25 4 min

VC 2.4L

RRC 4.0 L

TLC 5.2 L

Maximum inspiratory rates 252 L/ min

Maximum expiratory flow rate 24 L /min

Pa o2 63 MM Hg

PaCo2 37 MM Hg

1. What is the disorder of the man?

2. Is this mainly a restrictive or an obstructive disorder? Explain.

3. Why is the bronchodilator therapy ineffective for this patient?

4. What causes the hypoxemia?

5. Calculate the residual volume (RV) for this person before and after the bronchodilator therapy.

RV= TLC- VC.

6. What is the cause of this altered RV?

7. Calculate the tidal volume (TV) for this person before and after the bronchodilator therapy.

TV =AV/FT patient body weight.

Hint: TV is calculating in ML so you will need to convert L to ML before completing the equation.

8. Is each TV normal or altered?

9. Calculate the minutes ventilation ( MV) for this person before and after bronchodilator therapy MV=TV+ F

10. Is each MV normal or altered?