Which change is expected in Maximum Voluntary Ventilation for a patient with obstructive disease?

In patients with obstructive pulmonary disease, Maximum Voluntary Ventilation (MVV) is expected to show decreased values. MVV is a measure of the maximum amount of air that a person can breathe in and out in a specified period, reflecting overall respiratory muscle strength and lung function.

In obstructive diseases, such as chronic obstructive pulmonary disease (COPD) or asthma, airflow limitation occurs due to narrowing or obstruction of the airways. This can be caused by inflammation, bronchoconstriction, or mucus production. As a result, patients may struggle to achieve high MVV values. During forced expiration phases, air gets trapped in the lungs, leading to a decreased ability to ventilate adequately.

Thus, the functional impairment and the reduced air exchange in obstructive conditions contribute to a lower MVV, making the prediction of decreased values accurate in this context.