Comparison of clinical characteristics and outcomes of COVID-19 patients undergoing early versus late intubation from initial hospital admission: A systematic review and meta-analysis

BACKGROUND: The true impact of intubation and mechanical ventilation in coronavirus disease 2019 (COVID-19) patients remains controversial. METHODS: We searched Pubmed, Cochrane Library, Embase, and Web of Science databases from inception to October 30th, 2021 for studies containing comparative data of COVID-19 patients undergoing early versus late intubation from initial hospital admission. Early intubation was defined as intubation within 48 h of hospital admission. The primary outcomes assessed were all-cause in-hospital mortality, renal replacement therapy (RRT), and invasive mechanical ventilation (IMV) duration. RESULTS: Four cohort studies with 498 COVID-19 patients were included between February to August 2020, in which 28.6% had early intubation, and 36.0% underwent late intubation. Although the pooled hospital mortality rate was 32.1%, no significant difference in mortality rate was observed (odds ratio [OR] 0.81; 95% confidence interval 0.32–2.00; P = 0.64) among those undergoing early and late intubation. IMV duration (mean 9.62 vs. 11.77 days; P = 0.25) and RRT requirement (18.3% vs. 14.6%; OR 1.19; P = 0.59) were similar regardless of intubation timing. While age, sex, diabetes, and body mass index were comparable, patients undergoing early intubation had higher sequential organ failure assessment (SOFA) scores (mean 7.00 vs. 5.17; P < 0.001). CONCLUSIONS: The timing of intubation from initial hospital admission did not significantly alter clinical outcomes during the early phase of the COVID-19 pandemic. Higher SOFA scores could explain early intubation. With the advancements in COVID-19 therapies, more research is required to determine optimal intubation time beyond the first wave of the pandemic.