Question

A 28-year-old man presents with a 2-hour history of chest tightness, coughing, and wheezing. The history determines that he has had many such attacks in recent years, usually brought on by emotional factors or exertion; the attacks are generally treatable by self-medication at home. He has a history of hay fever, and other members of the family have had similar symptoms. Physical examination reveals dyspnea, orthopnea, and cyanosis. High-pitched, sibilant rhonchi occur on inspiration and expiration, and some coarse crepitations are audible. Pulse is 130/min and regular. Coughing produces viscid sputum. An emergency arterial PO2 is 65 mm Hg. What will likely be shown by pulmonary function studies during an acute attack?

1. Decreased FEV1
2. Increased vital capacity
3. Decreased residual volume
4. Decreased airway resistance
5. Increased arterial PO2

Answer 1

During an acute asthma attack, pulmonary function studies are likely to show decreased FEV1, increased vital capacity, decreased residual volume, increased airway resistance, and decreased arterial PO2.

Step-by-step explanation:

Pulmonary function studies during an acute asthma attack will likely show the following:

1. Decreased FEV1: FEV1 stands for forced expiratory volume in one second, which measures the amount of air a person can forcefully exhale in one second. A decrease in FEV1 is characteristic of an asthma attack.
2. Increased vital capacity: Vital capacity refers to the maximum amount of air a person can exhale after taking a deep breath. In an asthma attack, vital capacity may increase due to efforts to forcefully exhale.
3. Decreased residual volume: Residual volume refers to the amount of air left in the lungs after a maximal exhalation. In an asthma attack, residual volume may decrease because of the difficulty in fully exhaling.
4. Increased airway resistance: During an asthma attack, the airways become narrowed and inflamed, which leads to increased airway resistance.
5. Decreased arterial PO2: Arterial PO2 refers to the oxygen level in the blood. In an asthma attack, decreased arterial PO2 can occur due to impaired oxygen exchange in the lungs.