The role of ROX index–based intubation in COVID-19 pneumonia: a cross-sectional comparison and retrospective survival analysis

Background: Coronavirus disease 2019 (COVID-19) patients with acute respiratory failure who experience delayed initiation of invasive mechanical ventilation have poor outcomes. The lack of objective measures to define the timing of intubation is an area of concern. We investigated the effect of timing of intubation based on respiratory rate-oxygenation (ROX) index on the outcomes of COVID-19 pneumonia. Methods: This was a retrospective cross-sectional study performed in a tertiary care teaching hospital in Kerala, India. Patients with COVID-19 pneumonia who were intubated were grouped into early intubation (within 12 hours of ROX index <4.88) or delayed intubation (12 hours or more hours after ROX <4.88). Results: A total of 58 patients was included in the study after exclusions. Among them, 20 patients were intubated early, and 38 patients were intubated 12 hours after ROX index <4.88. The mean age of the study population was 57±14 years, and 55.0% of the patients were male; diabetes mellitus (48.3%) and hypertension (50.0%) were the most common comorbidities. The early intubation group had 88.2% successful extubation, while only 11.8% of the delayed group had successful extubation (P<0.001). Survival was also significantly more frequent in the early intubation group. Conclusions: Early intubation within 12 hours of ROX index <4.88 was associated with improved extubation and survival in patients with COVID-19 pneumonia.