PaO2/FiO2 ratio forecasts COVID-19 patients’ outcome regardless of age: a cross-sectional, monocentric study

Abstract

We studied the predictive value of the PaO2/FiO2 ratio for classifying COVID-19-positive patients who will develop severe clinical outcomes. One hundred fifty patients were recruited and categorized into two distinct populations (“A” and “B”), according to the indications given by the World Health Organization. Patients belonging the population “A” presented with mild disease not requiring oxygen support, whereas population “B” presented with a severe disease needing oxygen support. The AUC curve of PaO2/FiO2 in the discovery cohort was 0.838 (95% CI 0.771–0.908). The optimal cut-off value for distinguishing population “A” from the “B” one, calculated by Youden’s index, with sensitivity of 71.79% and specificity 85.25%, LR+4.866, LR−0.339, was < 274 mmHg. The AUC in the validation cohort of 170 patients overlapped the previous one, i.e., 0.826 (95% CI 0.760–0.891). PaO2/FiO2 ratio < 274 mmHg was a good predictive index test to forecast the development of a severe respiratory failure in SARS-CoV-2-infected patients. Moreover, our work highlights that PaO2/FiO2 ratio, compared to inflammatory scores (hs-CRP, NLR, PLR and LDH) indicated to be useful in clinical managements, results to be the most reliable parameter to identify patients who require closer respiratory monitoring and more aggressive supportive therapies. Clinical trial registration: Prognostic Score in COVID-19, prot. NCT04780373 https://clinicaltrials.gov/ct2/show/NCT04780373 (retrospectively registered).

Introducing Sarcopenia in Clinical Practice in Turkey

“…We attribute this result to our early application of HFNO or CPAP. In two recent cohort studies, they were able to determine the cut-off value of the PaO 2 /FiO 2 ratio as 274 mmHg in patients who developed ARF due to COVID-19 pneumonia (27,28). We also obtained similar findings in our study.…”

“…Some depend on advances in research and consensus or in political decision making. For instance, a worldwide initiative to agree on a global definition of sarcopenia is ongoing (28) and updated clinical guidelines are needed. Also, sarcopenia needs to be included in the WHO International Classification of Diseasesat present it is only listed in the version named Clinical Modification and the latest version ICD-11 does not properly include sarcopenia.…”

Complement C3 inhibition in severe COVID-19 using compstatin AMY-101

“…All patients in the experimental group exhibited rapid respiratory decompensation at the time of treatment initiation (mean PaO 2 /FiO 2 < 150). Typically, these patients with COVID-19 are characterized by a severe disease course, lengthy hospitalization, and high mortality rate (26)(27)(28). In this "difficult-to-treat" group of patients with COVID-19, we observed a beneficial trend for AMY-101 therapy added to standard dexamethasone and low-molecular weight heparin (LMWH) treatment.…”

Effective Regulation of Gut Microbiota With Probiotics and Prebiotics May Prevent or Alleviate COVID-19 Through the Gut-Lung Axis

“…Airway microbiota were altered in patients with burns and inhalation injury, and the abundance of Streptococcaceae and Enterobacteriaceae increased by 30% in hypoxemia patients compared to patients with the partial pressure of arterial oxygen/fraction of inspired oxygen (PaO 2 /FiO 2 ) ratio of more than 300; among the patients with PaO 2 /FiO 2 ratio ≤300, Prevotella melaninogenica and Corynebacterium genus-level were significantly enriched ( Walsh et al, 2017 ; Walton et al, 2021 ). Furthermore, PaO 2 /FiO 2 < 274 mmHg is considered to be a reliable prognostic biomarker for COVID-19 patients ( Sinatti et al, 2021 ). In a recent study in mice, it was found that after a respiratory infection, the relative abundance of Bacteroides increased and Firmicutes decreased ( Groves et al, 2018 ).…”