Prognostic Index for Compensation of Reduced Heart and Lung Functions in Patients with Sepsis

Magnitude of heart rate (HR) fluctuation during sepsis and septic shock can significantly impact tissue perfusion and organ dysfunction.

The aim of the study is to examine and compare the predictive characteristics of a composite index based on clinical parameters and demographic variables for early risk stratification of mortality in patients with sepsis.

Materials and Methods. In a multicenter retrospective cohort study, data from 257 patients with sepsis or septic shock were analyzed, including age, sex, height, weight, severity of illness, comorbidities, bedside hemodynamic and respiratory monitoring parameters upon admission to the ICU, and 3 hours after the initiation of intensive therapy, as well as treatment outcomes. Statistical characteristics of the generated Prognostic Index for Compensation of Reduced Cardiorespiratory Function (PICRCF) were assessed, calculated as the ratio of the product obtained by multiplying heart rate by respiratory rate and by age to the product obtained by multiplying of diastolic blood pressure by body surface area (BSA). To identify clinical and laboratory predictors of fatal outcomes, all patients were divided into two groups: survivors and those who died during treatment.

Results. The hospital mortality rate in the analyzed patient sample was 48%. Differences were found between those who died and those who survived in terms of age, scores on the Glasgow (RR), heart rate (HR), and blood pressure (BP), as well as PICRCF values both upon admission ((PICRCF 0) and after 3 hours of intensive care ((PICRCF 3). Notably, (PICRCF 3 demonstrated the highest discriminative performance among all studied predictors (AUC 0.800; 95% CI 0.744–0.855) with a cutoff value of 1.1 (sensitivity 69%, specificity 85%). In the Cox proportional hazards model, (PICRCF 3 was the only independent predictor of mortality (OR 1.313 (95% CI 1.062–1.623), p = 0.012). Additionally, PICRCF values were associated with the number of days without organ replacement support.

Conclusion. The indicators reflecting the state of the cardiovascular and respiratory systems, indexed according to anthropometric and age characteristics, have several advantages over standard prognostic scales in the early risk stratification of patients with sepsis. The simplicity, accessibility, and rapid measuring of the components for calculating PICRCF allow for dynamic assessment of the patient's condition from the first minutes of admission to the ICU.

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