P/PF ratio as a new criterion to classify the severity of acute respiratory distress syndrome
DOI:
https://doi.org/10.1590/Keywords:
Acute Respiratory Distress Syndrome, Disease Severity Index, Invasive Mechanical Ventilation, Intensive Care Unit.Abstract
The Berlin criteria has classified ARDS since 2012, indicating its severity via P/F within 24 hours after diagnosis. It can identify severe patients but suits moderate
and mild cases less precisely, necessitating the search for other tools that can accurately predict pulmonary impairment levels. A new evaluation uses PEEP levels for
its definitions following P/PF. This cross-sectional study was carried out in ICUs at a public hospital in southern Brazil with patients aged over 18 years who were under
mechanical ventilation and had been diagnosed with ARDS during hospitalization. The data that defined disease severity according to P/F and P/PF were compared on Stata®, version 12. The sample consisted of 85 patients, 91.7% of whom lied in the transmission window of COVID-19. The classification models showed differences (p<0.67) regarding P/F since they obtained moderate and severe results. Severe P/PF
patients had a 54.9% average death rate, near the total average mortality rate in this study (55.29%), showing that P/FP better predicts severity in patients with ARDS due to
its greater approximation of mortality percentages. However, furthers studies with larger samples and a greater number of classification variables may better predict ICU outcomes
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Copyright (c) 2026 Adriele Wience do Vale, Jeanny Franciela Kos Moleta, Péricles Martim Reche, Gabriel Gomes Vilar de Sousa, Paula Motta dos Santos
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