Association between trajectory of estimated plasma volume status and ICU mortality in sepsis patients: a retrospective cohort study.

BACKGROUND

This study aims to elucidate the association between estimated plasma volume status (ePVS) trajectory changes and intensive care unit (ICU) mortality.

METHODS

Data were extracted from the MIMIC-IV (version 3.1) database from 2008 to 2022. Patients aged 18 to 80 years who met the Sepsis-3 criteria were included. Patients who were not in their first hospital admission or first ICU stay, had an ICU stay shorter than 7 days or longer than 100 days, or lacked sufficient hemoglobin or hematocrit data to calculate ePVS at the required time points were excluded. Group-based trajectory modeling (GBTM) was used to identify distinct ePVS trajectories. Kaplan-Meier survival curves and Cox proportional hazards models were used to compare ICU mortality across ePVS trajectory groups. Restricted cubic splines (RCS) were used to analyze the dose-response relationship between Day 1 ePVS and outcomes.

RESULTS

Among 5208 patients with sepsis, three distinct ePVS trajectories were identified, namely Trajectory 1 (low-ascend), Trajectory 2 (medium-ascend), Trajectory 3 (high-ascend). Kaplan–Meier analysis showed Trajectory 1 having the highest survival probability among the ePVS trajectories. After multivariable adjustment, Trajectory 3 remained significantly associated with a higher risk of ICU mortality compared with Trajectory 1, with a hazard ratio (HR) of 1.20 (95%CI 1.01–1.44, p = 0.039). RCS analysis showed a significant linear association between Day 1 ePVS and ICU mortality. Subgroup analyses showed generally consistent results, and no significant interactions were detected.

CONCLUSION

Distinct ePVS trajectories were associated with ICU mortality in sepsis patients, with the high-ascend trajectory showing the highest mortality risk. CLINICAL TRIAL: Not applicable.