Adult Critical Care Specialty (ACCS) Practice Exam

What occurs in the lungs during the exudative phase of ARDS?

1. Increased production of surfactant

2. Presence of tiny microclots

3. Severe allergic reaction to fluid

4. Restoration of lung tissue

The correct answer is: Presence of tiny microclots

During the exudative phase of Acute Respiratory Distress Syndrome (ARDS), the lungs experience significant inflammatory changes that lead to the accumulation of protein-rich fluid in the alveolar space. This phase is characterized by the presence of tiny microclots within the pulmonary capillaries due to various factors, including the activation of coagulation pathways and inflammatory mediators. These microclots contribute to impaired gas exchange, as they can obstruct blood flow in the capillaries and increase the permeability of the alveolar-capillary membrane. Additionally, the presence of inflammatory cells and increased vascular permeability result in the characteristic pulmonary edema seen in ARDS. This accumulation of fluid and cellular debris severely hinders lung function and can lead to hypoxemia. In contrast, options that suggest increased production of surfactant, severe allergic reactions to fluid, or restoration of lung tissue do not accurately reflect the pathophysiological changes occurring during this initial phase of ARDS. During the exudative phase, surfactant production is typically reduced, allergic reactions to fluid are not a defining feature of ARDS, and lung tissue restoration occurs later in the process, often in the reparative phase. Thus, the presence of tiny microclots is the hallmark of the