The role of alveolo-arterial oxygen gradient and pneumonia severity index in predicting mortality in patients with COVID-19 pneumonia

Abstract

Purpose of the study is to determine the success rates of alveolo-arterial oxygen gradient (AaDO2) and the pneumonia severity index (PSI) in predicting mortality for the patients diagnosed with COVID-19 pneumonia. This retrospective study included patients who were treated with the diagnosis of COVID-19 pneumonia in the ICUs. Demographic characteristics, arterial blood gas values, radiological images and laboratory data of the patients were used through the hospital database and patient files. Group I patients consist of alive and Group II patients consist of deceased persons. 150 of 263 patients included in this study are in Group I and 113 are in Group II. RT-PCR test was positive in 20.9% of the patients. The most common symptom was dyspnea with 76.5% and the most common additional disease was hypertension with 58.1%.65% of patients had radiological involvement in both lungs, and the most common finding was the ground-glass opacity at 71.5%. In predicting mortality, PSI value was 135 in group I and 174 in group II (p<0.001);AaDO2 value was 154.88 mmHg in group I, 177.13 mmHg in group II (p<0.001), and this rate was different between the groups. Sensitivity is found at 84.1% and specificity at 67.3% for PSI, whereas sensitivity is found at 49.6% and specificity at 82.7% for the AaDO2 variable. It is important to estimate the mortality risk earlier for the patients with COVID-19 pneumonia who are also followed up in intensive care units. PSI is beneficial in detecting mortality risk whereas AaDO2 is valuable in determining the surviving patients.