There is some disagreement over when to perform intubation in the COVID-19 study. At the moment of intubation, researchers aimed to calculate the ROX (Respiratory rate-OXygenation) index, which is calculated as SpO2 divided by F102 divided by breathing frequency. Using a database of electronic health record data from patients with COVID-19 at 62 institutions, researchers performed a retrospective cohort study of intubated patients with COVID-19. The correlation between ROX index score and mortality was calculated using multivariate logistic regression analysis. Using the previously reported cutoffs as predicting effectiveness with a high-flow nasal cannula, they examined the ROX index as a continuous and categorical variable. A total of 1,087 patients were included in the analysis; the median age was 64, and more than half of them had diabetes. Of these patients, 55.2% passed away; 1.8% were discharged to hospice; 7.8% were discharged to their homes; 27.3% were discharged to other hospitals, and 7.8% had other dispositions. Death rates were shown to rise with patient age and the time between hospital admission and intubation. A higher ROX index score at the time of intubation was related to a decreased risk of death after controlling for sex, race, age, comorbidities, and length of time between admission and intubation. Logistic regression analysis revealed that there was an 8% reduction in mortality risk with every one-point increase in the ROX index score at the time of intubation (odds ratio 0.92, 95% CI 0.88-0.95). Subjects having a ROX index score of 4.88 or below at the time of intubation had a reduced risk of death (OR 0.62, 95% CI 0.47-0.81). A higher ROX index at the time of intubation was related to improved survival among a group of participants with COVID-19 who required mechanical ventilation.

Source: rc.rcjournal.com/content/67/10/1291