Critical care management of sepsis: a cost-analysis from a health care perspective

INTRODUCTION. Patients with severe sepsis often require admission to an intensive care unit (ICU) and their treatment is associated with high costs. Furthermore, both the incidence of sepsis and the severity of illness upon presentation are increasing [1]. OBJECTIVES. We aimed to estimate health care costs of patients admitted to the ICU with severe sepsis or septic shock and to explain variability in costs between individuals. METHODS. Data from an ongoing, prospective study of patients presenting with sepsis to the ICUs of two tertiary centers in the Netherlands were used to perform a cost-analysis from a health care perspective. Resource use was valued using a bottom-up micro-costing approach. Costs were estimated per day, per admission, and for subgroups of patients. A multivariable linear regression model was constructed to explain variability in costs between patients. Bootstrapping was used to estimate bias-corrected and accelerated confidence intervals (CI) and p-values to adjust for the uncertainty of the estimations due to the skewness of the cost data. RESULTS. Overall, 651 patients were included; 294 had severe sepsis and 357 had shock upon presentation. Total costs were ? 29,102 (? 26,598-? 31,690) per admission and ? 2,250 (? 2,235-? 2,266) per day in the ICU. Of the total costs 74% was related to accommodation, personnel and disposables, 12% to diagnostic procedures and 14% to therapeutic interventions. Patients presenting with septic shock had higher costs both per day (p< 0.001) and per admission (p< 0.001) compared to patients with severe sepsis. Survivors and non-survivors generated not significantly different overall costs (p=0.086), but non-survivors had higher costs per day (p< 0.001). In our multivariable model, baseline patient and illness factors explained 12% of the variance in total costs. Increased expenses were associated with septic shock, the presence of immunodeficiency, candidemia, and viremia. Decreased expenses were associated with the presence of diabetes mellitus and urinary tract infections. CONCLUSIONS. Mean costs of critical care management for severe sepsis or septic shock are almost ?30,000 per case of which the major part is fixed. This estimation is higher than estimations from studies performed with data from the 1990s, which might be caused by the changes in incidence and illness severity of sepsis since then. Baseline patient and illness characteristics explain only a small part of the variability in costs between patients.