Adult Critical Care Specialty (ACCS) Practice Exam

In ARDS, what happens to the alveoli during the exudative phase?

1. Expansion due to surfactant production

2. Collapse due to fluid accumulation

3. Improvement in gas exchange

4. Reduction in white blood cells

The correct answer is: Collapse due to fluid accumulation

During the exudative phase of Acute Respiratory Distress Syndrome (ARDS), the primary issue is the accumulation of fluid in the alveoli. This fluid, which is a result of increased permeability of the alveolar-capillary membrane due to various insults such as infection, trauma, or inflammation, leads to the collapse of the alveoli. As fluid fills the alveolar spaces, it disrupts the normal function of the alveoli, impeding gas exchange and thereby leading to hypoxemia. This phase is characterized by significant changes in lung function as well as inflammatory responses, which contribute to the pathophysiology of ARDS. The presence of fluid not only hampers the ability of the alveoli to expand properly, but it can also lead to atelectasis, where the alveoli cannot maintain their structure and collapse. Thus, the correct answer highlights the consequences of fluid accumulation on alveolar structure and function during this critical phase of ARDS.