Body Composition Analysis in Septic Shock Patients Receiving Protocol-Driven Resuscitation Bundle Therapy: A Prospective Observational Study

Abstract Background: Bio-electrical impedance analysis (BIA) is a rapid, simple, and noninvasive tool for assessing volume status in various diseases. Body composition analysis using BIA may identify factors associated with poor outcomes in critically ill patients. Little is known, however, about the relationship between the results of body composition analysis in the emergency department (ED) and mortality in septic shock patients.Objectives: This study assessed the association between parameters identified by body composition analysis and mortality in patients with septic shock who underwent protocol-driven resuscitation bundle therapy in the ED.Methods: Data were prospectively collected on adult patients with septic shock who underwent protocol-driven resuscitation bundle therapy between December 2019 and December 2020. Body composition was determined in the ED using BIA with the patient in the supine position. Septic shock was defined by sepsis-3 criteria, and the primary outcome was 30-day mortality. Results: The study included 218 patients, of whom 58 (26.6%) died within 30 days. The mean time from ED admission to the measurement of body composition was 5.4 hours. The average ratio of extracellular water (ECW) to total body water (TBW) was significantly higher in non-survivors than in survivors (0.412 vs. 0.400, p=0.001). The optimal ECW/TBW cutoff for predicting 30-day mortality was 0.40, with mortality rates being significantly higher in patients with ECW/TBW >0.4 than in patients with ECW/TBW≦0.4 (37.8% vs. 17.5%, p=0.001). Multivariate analysis showed that ECW/TBW >0.4 (odds ratio [OR], 2.11; 95% confidence interval [CI], 1.05–4.23, p = 0.036), active cancer (OR, 2.39; 95% CI, 1.06–5.38, p=0.036), prothrombin time (OR, 2.77; 95% CI, 1.29–5.93, p=0.009), and initial lactate level (OR, 1.15; 95% CI, 1.03–1.28, p=0.010) were significantly associated with 30-day mortality.Conclusions: The ECW/TBW>0.40 is the only body composition parameter associated with 30-day mortality in patients with septic shock.