Objective To explore the application value of serum high mobility group protein B1 (HMGB1), S100β combined with bispectral index (BIS) in the early diagnosis of sepsis-associated encephalopathy (SAE).

Methods The medical records of 87 patients with sepsis admitted to the emergency department of the Second People’s Hospital of Wuhu City from January 2021 to December 2023 were retrospectively analyzed, and the patients were divided into the SAE group (n = 35) and non-SAE group (n = 52) according to whether they were complicated with SAE. The clinical data, serum levels of HMGB1 and S100β and 24-hour BIS between two groups were compared, the influencing factors of SAE occurrence in septic patients and clinical value of HMGB1, S100β combined with BIS in the early diagnosis of SAE were analyzed.

Results The scores of APACHEⅡ and SOFA in the SAE group were significantly higher than those in non-SAE group (P ＜ 0.01). The serum levels of HMGB1 and S100β in the SAE group were significantly higher than those in non-SAE group (P ＜ 0.01), while the BIS levels were significantly lower than those in non-SAE group (P ＜ 0.01). The APACHEⅡ score, SOFA score, HMGB1, S100β and BIS were the independent factors of SAE occurrence in sepsis patients (P ＜ 0.01). The results of ROC curve analysis showed that the AUC, sensitivity and specificity of SAE in early diagnosis of sepsis patients with serum HMGB1 and S100β combined with BIS was 0.891, 91.43% and 84.62%, respectively, which was better than independent diagnosis of each index (P ＜ 0.05).

Conclusions The combined detection of serum HMGB1, S100β and BIS has a good clinical application value in early diagnosis of SAE.