What can happen to alveolar pressures during volume-control ventilation when lung conditions worsen?

• A. They improve significantly
• B. They rise leading to potential over distention
• C. They stabilize at normal levels
• D. They drop to unsafe levels

Answer: (B)

In volume-control ventilation, the ventilator is set to deliver a specific tidal volume regardless of the pressure required to achieve that volume. When lung conditions worsen—such as in cases of acute respiratory distress syndrome (ARDS) or severe pneumonia—the compliance of the lungs decreases. This means that the lungs become stiffer and require more pressure to achieve the same volume of air.

As a result, the pressure in the alveoli rises. If the pressures continue to increase without appropriate adjustments to the ventilator settings, this can lead to overdistention of the alveoli. Overdistention poses the risk of causing barotrauma, where the alveoli may rupture due to excessive pressure, leading to complications such as pneumothorax. Therefore, during the deterioration of lung conditions under volume-control ventilation, the increase in alveolar pressure is a significant concern, which is why this option is the most accurate depiction of events in this scenario.