Lung Recruitability in SARS-CoV-2 Associated Acute Respiratory Distress Syndrome: A Single-center, Observational Study

Mortality of patients with acute respiratory distress syndrome (ARDS) = 61.5%. The question was: Can the lungs in all these patients be recruited with high expi positive pressure? With high PEEP (15cmH2O): the pressure plateau became very high (>45cmH2O) with poor response, or sometimes resulted in a poor oxygenation response with increased motor pressure and/or hypotension. They created an indicator to quantify the recruitment potential of the lungs: R/I ratio: calculating how much of a PEEP-induced increase in end-expi volume is distributed between the recruited lung and the inflation or hyperinflation of the 'baby lung' when higher PEEP is applied. This score ranges from 0 to 2: R/I = 1= high recruitment probability, the volume will be similarly distributed between the recruited lung and the baby lung. This method can be performed at the patient's bedside, requiring a breathing maneuver on any ventilator. To calculate it: https://crec.coemv.ca or formula in the article. A threshold of 0.5 was used to define high recruitment (R/I>=0. 5) or low recruitment (R/I<0.5), with ratios measured from 15 to 5 cmH2o in all patients. On the 12 patients: 7 were in the prone position, 3 were in the prone position and received ECMO (extracorporeal membrane oxygenation), 3 died. 10 had R/I<0.5 at D1. Those who did not have prone position maintained ratios of less than 0.5 (except for 1 of the 17 measurements). VD cure alternation was associated with a ratio>=0.5 (13 out of 36 measures). In patients in a prone position, PaO2/FiO2 increased from 120+-61 to 182+-140mmHg.