Timing of tracheostomy and hospital mortality in mechanically ventilated ICU patients: a prospective cohort study

Abstract Background The optimal timing of tracheostomy in mechanically ventilated critically ill patients remains controversial. Although early tracheostomy may reduce complications related to prolonged endotracheal intubation, its association with clinically important outcomes, particularly mortality, is still debated. This study aimed to compare clinical outcomes between early and late tracheostomy among patients admitted to the intensive care unit. Methods This prospective cohort study included 78 mechanically ventilated ICU patients who underwent tracheostomy at Shahid Beheshti Hospital, Kashan, Iran, during 2025–2026. Patients were categorized according to the interval between endotracheal intubation and tracheostomy into an early tracheostomy group, defined as tracheostomy performed within 10 days of intubation, and a late tracheostomy group, defined as tracheostomy performed after 10 days. Demographic characteristics, comorbidities, Glasgow Coma Scale score, duration of ICU stay, duration of intubation before tracheostomy, post-tracheostomy length of stay, and mortality outcomes were recorded. Between-group comparisons were performed using the chi-square test, Fisher’s exact test, and independent-samples t-test, with statistical significance set at P < 0.05. Exploratory multivariable logistic regression was performed to assess the association between tracheostomy timing and hospital mortality after adjustment for potential confounders. Results Of the 78 included patients, 32 underwent early tracheostomy and 46 underwent late tracheostomy. The two groups were comparable in terms of age, sex, comorbidities, reason for ICU admission, pre-tracheostomy sedative use, and pre-procedure Glasgow Coma Scale score. As expected, patients in the late tracheostomy group had significantly longer ICU stay and longer duration of endotracheal intubation before tracheostomy compared with the early tracheostomy group ( P < 0.001). No significant differences were observed between the groups in ICU length of stay or hospital length of stay after tracheostomy. ICU mortality was also not significantly different between the early and late groups. However, hospital mortality was significantly higher in the late tracheostomy group than in the early tracheostomy group (65.2% vs. 40.6%, P = 0.032). After adjustment for age, GCS score, and reason for ICU admission, the association was attenuated and did not reach statistical significance (aOR 2.88, 95% CI 0.97–8.52; P = 0.057). Conclusion Hospital mortality was lower among patients undergoing early tracheostomy in the unadjusted analysis; however, this association did not remain statistically significant after multivariable adjustment. Larger studies with comprehensive adjustment for illness severity are needed to clarify whether tracheostomy timing independently influences mortality.