What complication does positive end-expiratory pressure (PEEP) prevent in patients on mechanical ventilation?

Positive end-expiratory pressure (PEEP) is a mode of mechanical ventilation that maintains a certain amount of pressure in the airways at the end of expiration. This pressure helps to keep the alveoli open, thereby preventing their collapse. One of the significant complications that can arise in mechanically ventilated patients is absorption atelectasis, which occurs when the alveoli collapse due to the absorption of gases, particularly in situations where areas of the lung are not being adequately ventilated, leading to low volume in certain lung regions.

When PEEP is applied, it helps to maintain functional residual capacity (FRC) and recruit collapsed or poorly ventilated alveoli, thus preventing the excessive absorption of oxygen and nitrogen. By keeping the alveoli open, PEEP enhances gas exchange and reduces the likelihood of areas in the lung becoming atelectatic. This is particularly important in certain conditions such as acute respiratory distress syndrome (ARDS) or when there are concerns about fluid in the alveoli.

In the context of the other options: while PEEP can have beneficial effects on pulmonary hypertension by reducing right ventricular strain, and while it can potentially help mitigate some aspects of oxygen toxicity by improving oxygenation efficiency, it is not a direct intervention for those issues. Tension