Cohort study reveals elevated late-stage plasma volume expansion predicts in-hospital mortality in sepsis patients, indicating key non-linear thresholds for fluid management.
Key Points
To evaluate the association between dynamic changes in estimated plasma volume status and in-hospital mortality among adult intensive care unit patients with sepsis.
Retrospective cohort analysis of N=17,403 adult sepsis patients meeting Sepsis-3 criteria from the MIMIC-IV (v2.2) database.
Calculated estimated plasma volume status (ePVS) using hemoglobin and hematocrit at early (ePVS1) and late-ICU (ePVS2) time points, as well as ePVS change.
Assessed associations with in-hospital mortality using multivariable logistic regression, restricted cubic splines, and threshold analysis.
In-hospital mortality was 13.2% across the cohort, with non-survivors demonstrating significantly higher late-ICU ePVS and dynamic ePVS change.
Late-ICU ePVS (adjusted OR = 1.14, 95% CI: 1.11–1.18, p < 0.001) and ePVS change (adjusted OR = 1.04, 95% CI: 1.02–1.05, p < 0.001) were independently associated with in-hospital mortality, while early ePVS was not significant.
Non-linear spline models identified a low-risk window at an ePVS2 of 6–8 dL/g and an ePVS change of -4.5 to 2, with risk rising sharply at an ePVS2 ≥ 8 dL/g or ePVS change ≥ 2.