What does the term "auto-PEEP" indicate?

The term "auto-PEEP" refers to the buildup of pressure in the respiratory system due to incomplete exhalation during mechanical ventilation. This phenomenon occurs when a patient does not have enough time to fully exhale before the next mechanical breath is initiated. As a result, air remains trapped in the lungs, increasing the end-expiratory lung volume and thus the intrathoracic pressure. This can lead to impaired respiratory function, reduced venous return, and decreased cardiac output. Recognizing and managing auto-PEEP is crucial in ventilation strategies to ensure adequate gas exchange and prevent potential complications associated with high intrinsic respiratory pressures.