Volutrauma and atelectrauma: which is worse?

Excerpt

The first recognized form of ventilator-induced lung injury (VILI) was named barotrauma, a word that stresses the role of pressure as a causative agent [1]. Following the work of Dreyfuss et al., which called attention to volume instead of pressure [2], volutrauma was recognized as the primary driver of VILI. While airway pressure distributes across the series-linked thoracic cage and lungs in proportions determined by their relative elastances, volume is a unique variable common to both. Any conceptual distinction between volutrauma and barotrauma vanishes if one considers transpulmonary pressure (PL; stress) instead of airway pressure, and strain (i.e., volume change (∆V) relative to resting lung volume (functional residual capacity (FRC)) instead of tidal volume [3]. These two variables are inextricably coupled by a proportionality constant having the units of pressure (specific elastance, or E_spec), which in man approximates 12–13 cmH₂O [4]: or …