What does the adjustment of PEEP aim to achieve?

The adjustment of PEEP (Positive End-Expiratory Pressure) is primarily aimed at preventing alveolar collapse and improving oxygenation. By maintaining a pressure in the airways at the end of expiration, PEEP helps keep the alveoli open, thus increasing the surface area available for gas exchange. This leads to better oxygenation of the blood and can improve overall respiratory function, especially in patients with conditions such as acute respiratory distress syndrome (ARDS) or other forms of lung injury.

PEEP enhances the aeration of collapsed or poorly ventilated lung units, improving VQ (ventilation-perfusion) matching and reducing shunting, which directly contributes to improved oxygen saturation levels. While PEEP can also influence the work of breathing and minute ventilation indirectly by improving lung mechanics and gas exchange, its primary role is in maintaining alveolar stability and optimizing oxygenation during mechanical ventilation.

The other choices, while they may relate to ventilatory strategies, do not capture the primary objective of adjusting PEEP as accurately.