A client with a history of asthma is admitted with audible wheezing over both lung fields. The nurse knows that the wheezing associated with asthma is due to: A. Narrowing of the bronchial lumen B. Partial obstruction of the larynx C. Infection of the tracheobronchial tree D. Chronic dilation of the alveoli

In this question, we are asked to determine the cause of wheezing associated with asthma. The correct answer is: A. Narrowing of the bronchial lumen.

The wheezing associated with asthma is due to the narrowing of the bronchial lumen. Asthma is a chronic respiratory condition characterized by inflammation and narrowing of the airways (bronchi), which makes breathing difficult. The bronchial lumen is the inner space of the bronchial tubes, through which air flows in and out of the lungs. When the bronchial lumen narrows, air has a harder time passing through, causing the wheezing sound as the person with asthma struggles to breathe.

B. Partial obstruction of the larynx: This is incorrect because the larynx, also known as the voice box, is not directly involved in the wheezing associated with asthma. While it is located in the upper respiratory tract and conducts air in and out of the lower respiratory tract, its obstruction is more likely to cause stridor, which is a high-pitched breathing sound, not wheezing. C. Infection of the tracheobronchial tree: This option is also incorrect because, although infections in the tracheobronchial tree can cause respiratory symptoms, they do not cause the specific wheezing sound associated with asthma. Rather, infections can lead to cough, mucus production, and other respiratory symptoms. D. Chronic dilation of the alveoli: This is not the correct answer because chronic dilation of the alveoli, called emphysema, is a condition different from asthma, and it is associated with the destruction of the alveolar walls and air trapping. This condition leads to shortness of breath and decreased lung function, but not the wheezing characteristic of asthma.