Predictive Value of Inflammatory Burden Index for Sepsis in Critically Ill Patients with Extensive Burns: A Decade-Long Cohort Study

Objective: We aimed to explore the correlation between the inflammatory burden index (IBI) and the development of sepsis in critically ill patients with extensive burns. Methods: This retrospective cohort study included extensively burned patients who were admitted to the First Affiliated Hospital of Army Medical University from January 1, 2014, to December 31, 2023. These patients were divided into two groups based on the presence or absence of sepsis within 28 days after burns (the sepsis group and the nonsepsis group). Furthermore, the patients’ basic information, burn severity, blood parameters in the early post-burn period (within 48h after burns), mechanical ventilation, ICU length of stay and the outcome were collected. Independent samples Mann–Whitney U -tests and chi-square tests were performed with respect to the indicators between the groups. Univariate and multivariate logistic regression analyses were conducted on the basis of indicators that exhibited statistically significant differences to identify independent risk factors pertaining to sepsis occurrence. Receiver operating characteristic (ROC) curves were plotted to evaluate the predictive efficacy of indicators such as the IBI and determine optimal cutoff values. Results: A total of 178 critically ill patients with extensive burns were enrolled in this study. Significant differences were observed in the total body surface area (TBSA), burn index (BI), C-reactive protein (CRP) level and neutrophil-to-lymphocyte ratio (NLR), IBI, revised Baux score (rBaux), mechanical ventilation and ICU length of stay between the sepsis group and the nonsepsis group (P < 0.05). Logistic regression analysis identified the IBI in the early post-burn period as an independent risk factor for sepsis (P < 0.05), and its predictive performance surpassed that of the CRP level. The optimal cut-off value of the IBI was 695.01, and combination of the IBI with the BI led to further improvements in predictive performance. Conclusion: The IBI in the early post-burn period offers good predictive value for the development of sepsis in critically ill patients with extensive burns, which is helpful for formulating treatment strategies, including early surgical intervention, antibiotic application, and early enteral nutrition, etc. to reduce the incidence of sepsis. Keywords: inflammatory burden index, sepsis, extensive burns, C-reactive protein, burn index