Low-PEEP Mechanical Ventilation and P/F Ratio Evolution in COVID-19 Patients

Abstract

\n Background Critically ill COVID-19 patients are burdened by high mortality. Evaluation to improve patients’ management was performed using strict patient criteria for Intensive Care Unit (ICU) admission, a low- positive end-expiratory pressure (PEEP) setting and standard thromboembolism treatment. Objectives of this study was to report the effects of this strategy on P/F-ratio evolution during mechanical ventilation (MV), ICU length of stay (LOS) and MV length.Methods A retrospective analysis was conducted on all consecutive patients with acute respiratory distress due to COVID-19 pneumonia admitted into ICU from March 2nd to January 15th, 2021. Patients were treated with a low-PEEP strategy (PEEP 10 cmH2O if BMI < 30 Kg m-2, PEEP 12 cmH2O if BMI 30-50 Kg m-2, PEEP 15 cmH2O if BMI > 50 Kg m-2) and therapeutic anticoagulation in case of thrombosis or D-dimer greater than 1’500 ng ml-1.Results 79 patients were on invasive MV. Average applied PEEP was 11 ± 2.9 cmH2O for BMI < 30 Kg m-2, 16 ± 3.18 cmH2O for BMI > 30 Kg m-2. After low-PEEP application, patients’ P/F ratio presented daily improvement from admission during next 72 hours (p<0.001; CI 99%) that resulted statistically significant for each single day after oro-tracheal intubation (OTI). Median ICU length of stay (LOS) was 15 days (10–28); median duration of MV was 12 days (8–26). The ICU mortality rate was 31.6%.Conclusions A combination of low-PEEP treatment resulted in P/F persistent daily ratio improvement during first 72 hours after OTI. A low-PEEP strategy could be beneficial in hemodynamic than respiratory terms.