Effect of timing of intubation on clinical outcomes of patients with septic shock: a retrospective cohort study

Evidence-based data regarding the timing of the application of invasive mechanical ventilation among adults with septic shock is insufficient. The guidelines fail to provide clear advice about the optimal time to initiate this support. Consequently, we aimed to investigate whether early intubation could improve survival rates in septic shock patients. We conducted a retrospective analysis of the MIMIC-IV database to evaluate the effectiveness of early intubation on mortality in a cohort of septic shock patients. Adults diagnosed with septic shock, according to the Sepsis-3 definition, were included. They were categorized into an early intubation group (first 8 h after vasopressor initiation) and a non-early intubation group (unexposed). A propensity score matching (PSM) analysis was used to balance the baseline characteristics between the two groups. The primary outcomes were 30-day and 90-day all-cause mortality rates. In addition, we employed the restricted cubic spline to analyze the potential non-linear relationship between the timing of intubation and 30-day or 90-day all-cause mortality. A total of 6864 adult patients, of whom 2048 were intubated in the first 8 h, were evaluated in the final cohort. Following a 1:1 PSM procedure, 2786 patients were successfully paired. At 30 days, 288 of 1393 patients (20.7%) in the early intubation group and 381 of 1393 patients (27.4%) in the non-early intubation group had died (hazard ratio [HR] 0.717; 95% confidence interval [CI] 0.616-0.836; p < 0.001). Similarly, the results also showed that early intubation was associated with a lower 90 day all-cause mortality rate (HR 0.761; 95% CI 0.663-0.874; p < 0.001). Furthermore, ICU and hospital lengths of stay were significantly different between the groups (3.6 [1.9, 7.1] vs. 2.3 [1.3, 4.3]; p < 0.001 and 8.9 [5.4, 15.1] vs. 7.2 [4.5, 12.0]; p < 0.001). In the subgroup analysis, we further confirmed the robustness of our findings. Additionally, we found that the timing of intubation is inversely U-shaped correlated to the 30 day all-cause mortality rate. Among adult patients with septic shock, the early initiation of invasive mechanical ventilation could improve clinical outcomes. The timing of intubation demonstrated an inverse U-shaped association with the 30 day all-cause mortality rate, with the peak risk of death occurring at 50.5 h after septic shock.