Adult Critical Care Specialty (ACCS) Practice Exam

In the proliferative phase of ARDS, how does pulmonary function typically manifest?

1. Improvement in lung compliance

2. Severe hypoxemia unresponsive to oxygen therapy

3. Increased pulmonary surfactant production

4. Complete recovery of lung function

The correct answer is: Severe hypoxemia unresponsive to oxygen therapy

In the proliferative phase of ARDS (Acute Respiratory Distress Syndrome), the patient typically experiences deterioration in pulmonary function, which is characterized by severe hypoxemia that is often unresponsive to oxygen therapy. During this phase, the injury to the alveolar-capillary membrane results in impaired gas exchange, leading to critically low oxygen levels in the blood. This hypoxemia is a hallmark of ARDS and can be challenging to correct solely with supplemental oxygen due to the underlying pathophysiological changes in the lungs, including inflammation and fluid accumulation. Other choices reflect less common or inaccurate manifestations during this phase. Improvement in lung compliance is generally not seen, as compliance tends to be reduced due to atelectasis and inflammatory processes. Increased pulmonary surfactant production would not typically occur in this phase either; in fact, surfactant dysfunction can contribute to poor lung mechanics and gas exchange issues. Finally, complete recovery of lung function is not typical during the proliferative phase; recovery occurs later, in the resolution phase, if the patient is able to heal adequately.