Role of PAO2/FIO2 Ratio at Admission as Predictors of Respiratory Failure in Covid-19 Patients

Latha V (1) , Virender Singh (2) , Vinutha (3)
(1) a:1:{s:5:"en_US";s:19:"Md general medicine";} , India
(2) Junior resident, Department of general medicine, ESICMC-PGIMSR, Rajajinagar. , Aruba
(3) Junior resident, Department of general medicine, ESICMC-PGIMSR, Rajajinagar , Azerbaijan



Introduction: The early identification of factors that predict respiratory failure in patients affected by coronavirus disease (COVID-19) will assist therapeutic decisions and patient flow management.

Methodology: We collected, at the time of admission, routine clinical, laboratory, and imaging parameters of hypoxia, lung damage, inflammation, and organ dysfunction in a consecutive series of 60 COVID-19 patients admitted to ESICMC-PGIMSR hospital Rajajinagar.

Results: Patients were divided into mild, moderate and severe ARDS based on Pao2/Fio2 ratio at admission (berlin criteria). The requirement of CPAP, mechanical ventilator, duration of hospital stay and death was compared in the 3 group of patients. Out of 60 patients 25patients had pao2/fio2 ratio <300-200 mm Hg (mild), 18 had 200-100 mm Hg (moderate) and 17 of them had <100 mm Hg (severe). Β Those patients with lower PaO2/FiO2 ratio at admission were significantly needed the assistance of CPAP, Mechanical ventilator for their hypoxia management, they also had prolonged hospital stay (PHS, >21 days) than patients with higher Pao2/Fio2 ratio.Β  Patients in lower PaO2/FiO2 ratio i.e. in severe group had high mortality rate.

Conclusions: The PaO2/FiO2 ratio on admission is independently associated with significant mortality and morbidity in COVID-19 patients. Larger prospective studies are needed to confirm this finding.

Key word: Covid-19, ARDS, Pao2/Fio2 ratio.


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Latha V (Primary Contact)
Virender Singh
V, L., Singh, V. ., & Vinutha. (2022). Role of PAO2/FIO2 Ratio at Admission as Predictors of Respiratory Failure in Covid-19 Patients. Journal of Current Medical Research and Opinion, 5(07), 1276–1280.
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