Recruitment-to-inflation ratio measured with modern intensive care unit ventilators: How accurate is it?

• Published in: Critical care (London, England) Vol. 26; no. 1; p. 85
• Main Authors: Cour, Martin, Biscarrat, Charlotte, Stevic, Neven, Degivry, Florian, Argaud, Laurent, Guérin, Claude
• Format: Journal Article
• Language: English
• Published: England BioMed Central Ltd 28.03.2022; BioMed Central; BMC
• Subjects: Acute respiratory distress syndrome; Care and treatment; Coronaviruses; Correspondence; COVID-19; Critical care; Evaluation; Humans; Intensive care; Intensive Care Units; Life Sciences; Lung volume measurements; Respiratory distress syndrome; Ventilators; Ventilators, Mechanical; France; Germany
• ISSN: 1364-8535; 1466-609X; 1364-8535; 1366-609X
• DOI: 10.1186/s13054-022-03961-x

The recruitment-to-inflation (R/I) ratio is a recent tool that has been developed to evaluate the potential for lung recruitment in patients with acute respiratory distress syndrome (ARDS) [1]. At high PEEP, the compliance was either unchanged (40 ml/cmH2O) or increased to 60 or 80 ml/cmH2O to obtain the abovementioned R/I ratios. [...]for a 10 cmH2O difference between low and high PEEP, the expected Vrec was 0, 200 and 400 ml, respectively. [...]our results showing large errors in the measurements of the true values of R/I, despite highly standardized bench conditions, suggest that using a single cut-off R/I value to individualize treatments of a given patient may be inappropriate and could even lead to opposite therapeutic strategies.