Abstract: Background The number of pediatric patients undergoing prolonged mechanical ventilation (PMV) in pediatric intensive care units (PICUs) has been rapidly increasing, but the factors influencing mortality among these patients remain unclear. Objective To analyze the factors affecting mortality in pediatric patients receiving PMV in PICUs. Design Retrospective cohort study. Methods This study included consecutive cases of invasive mechanical ventilation for ≥14 days with ≥6 hours of ventilation per day at the PICU of the Children's Hospital of Chongqing Medical University from October 1, 2020, to June 30, 2021. Patients were followed for one month after discharge with survival and mortality as outcomes. Data were collected at PICU admission, during PICU treatment, and at discharge. Cox regression analysis was used to explore factors influencing mortality. Main outcome measures Factors influencing mortality in children undergoing PMV. Results During the study period, 1 815 patients were admitted to the PICU with 1 144 requiring mechanical ventilation. One hundred and twenty-seven patients met the inclusion criteria for PMV, among which 99 survived and 28 (22.0%) died during the first month of discharge. A multivariable Cox proportional hazards model was constructed using 10 variables from information at PICU admission, during treatment, and at discharge. The results showed that for risk of death during the first month of discharge, a PELOD-2 score ≥4 during the course was associated with a 2.9-fold increased risk (HR=2.893, 95% CI: 1.182-7.079), blood transfusion therapy with a 2.8-fold increased risk (HR=2.766, 95% CI: 1.012-7.558), blood purification therapy with a 3-fold increased risk (HR=2.978, 95% CI: 1.108-8006), and mechanical ventilation duration ≥30 days with a 3.1-fold increased risk (HR=3.062, 95% CI: 1.282-7.312), while hospital stay length≥35 days was associated with an 89% reduction in the risk of death (HR=0.112, 95% CI: 0.037-7.312). Conclusion The mortality rate among children receiving PMV in the PICU was 22%. Factors such as a PELOD-2 score ≥4, blood transfusion, blood purification therapy, and mechanical ventilation duration ≥30 days were associated with approximately a threefold increase in the risk of death during the first month after discharge, while hospital stay length ≥35 days was associated with a decreased risk of death.

Key words: Peidatric, Prolonged mechanical ventilation, extubation, Prognosis