Timing of intubation and clinical outcomes in critically ill COVID-19 patients with respiratory failure

Background: Coronavirus disease 2019 (COVID-19) can cause severe respiratory symptoms including acute respiratory distress syndrome (ARDS). The primary treatment involves respiratory support including intubation and non-invasive respiratory support. The effect of timing for intubation on outcomes remains controversial. This study aims to investigate the impact of early intubation (EI) vs. deferred intubation (DI) on patient outcomes. Methods: This retrospective cohort study included 397 adult subjects with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection who suffered from respiratory failure requiring intensive care unit (ICU) admission from April 1, 2021 to December 31, 2021. Subjects were categorized into two groups: the EI group (intubated within 72 hours of admission) and the DI group (intubated after 72 hours after admission). The primary outcome was ICU-free days within 30 days. The impact of timing of intubation on mortality was also assessed. Results: There were 102 subjects (25.7%) in the EI group and 295 subjects (74.3%) in the DI group. The EI group had a lower median ICU-free days compared to the DI group {4 [0, 20] vs. 19 [0, 25] days, P<0.001}. However, after adjusting for potential confounding factors including disease severity, there was no difference in successful ICU discharge between groups [adjusted hazard ratio (aHR), 1.08; 95% confident interval (CI): 0.78–1.50; P=0.64]. The 30-day mortality rate was higher in the EI group (29.4% vs. 15.3%, P=0.002). Ventilator-free days were lower in the EI group with a median of 8 [0, 22] days compared to 30 [16, 30] days in the DI group. The EI group had higher rate of secondary bacterial infections (56.9% vs. 40.3%, P=0.004). Conclusions: This study demonstrated that DI with non-invasive respiratory support could be employed in COVID-19 patients with respiratory failure through careful patient selection and close monitoring.