Lung mechanics in type L CoVID-19 pneumonia: a pseudo-normal ARDS

Background: This study was conceived to provide systematic data about lung mechanics during early phases of CoVID-19 pneumonia, as long as to explore its variations during prone positioning.

Methods: We enrolled four patients hospitalized in the Intensive Care Unit of "M. Bufalini" hospital, Cesena (Italy); after the positioning of an esophageal balloon, we measured mechanical power, respiratory system and transpulmonary parameters and arterial blood gases every 6 hours, just before decubitus change and 1 hour after prono-supination.

Results: Both respiratory system and transpulmonary compliance and driving pressure confirmed the pseudo-normal respiratory mechanics of early CoVID-19 pneumonia (respectively, C_RS 40.8 ml/cmH₂O and DP_RS 9.7 cmH₂O; C_L 53.1 ml/cmH₂O and DP_L 7.9 cmH₂O). Interestingly, prone positioning involved a worsening in respiratory mechanical properties throughout time (C_RS,SUP 56.3 ml/cmH₂O and C_RS,PR 41.5 ml/cmH₂O - P 0.37; C_L,SUP 80.8 ml/cmH₂O and C_L,PR 53.2 ml/cmH₂O - P 0.23).

Conclusions: Despite the severe ARDS pattern, respiratory system and lung mechanical properties during CoVID-19 pneumonia are pseudo-normal and tend to worsen during pronation.

Trial registration: Restrospectively registered.