What is the purpose of using positive end-expiratory pressure (PEEP) in mechanical ventilation?

The primary purpose of using positive end-expiratory pressure (PEEP) in mechanical ventilation is to prevent atelectasis by keeping the alveoli open. PEEP achieves this by maintaining a baseline pressure in the airways during expiration, which helps to keep the alveoli from fully collapsing. By preventing the collapse of the small air sacs, PEEP increases the surface area available for gas exchange, thereby improving the overall ventilation-perfusion ratio and enhancing oxygenation in the lungs.

In situations where the lungs are vulnerable to collapse due to fluid in the alveoli, poor lung compliance, or other factors, PEEP acts as a critical component of mechanical ventilation strategies. It facilitates better oxygenation and ventilation over time, reducing the work of breathing and improving patient outcomes.

Although other options may relate to different aspects of mechanical ventilation, none address the core function of PEEP as effectively as the prevention of atelectasis.