Abstract:

Airway closure refers to a lack of communication between proximal airways and alveoli due to airway collapse.It occurs in about 30% of patients, rising to up to 65% of patients with obesity and ARDS.“Liquid bridge formation,” “small airway compliant collapse,” or “surfactant depletion” can lead to airway closure, however, the exact mechanism is unknown.Airway closure not only affects the function of lung ventilation, but also in the process of mechanical ventilation, ignoring this phenomenon can lead to errors in lung recruitment assessment and respiratory mechanics measurement.This can affect the appropriate setting of ventilator parameters, even leading to or aggravating lung injury, and impacting on the fluid responsiveness assessment index based on heart-lung interaction.Airway closure can be monitored clinically by “low flow method” or “conductive pressure method”.This article reviews the phenomenon of airway closure and its impacts on respiration and circulation, emphasizing the importance of monitoring airway closure to deepen clinicians’ understanding and thereby improve the prognosis of mechanically ventilated patients with airway closure.

Key words: Airway closure, Airway opening pressure, Lung injury, Respiratory mechanics