Early diagnosis of sepsis-related hepatic dysfunction and its prognostic impact on survival: a prospective study with the LiMAx test

Abstract
Liver dysfunction can derive from severe sepsis and might be associated with poor prognosis. However, diagnosis of septic liver dysfunction is challenging due to a lack of appropriate tests. Measurement of maximal liver function capacity (LiMAx test) has been successfully evaluated as a new diagnostic test in liver resection and transplantation. The aim of this study was to evaluate the LiMAx test during sepsis in comparison to biochemical tests and the indocyanin green test (ICG-PDR). We prospectively investigated 28 patients (8 female and 20 male, age range 35 to 80 years) suffering from sepsis on a surgical ICU. All patients received routine resuscitation from septic shock (surgery, fluids, catecholamines, antibiotic drugs). The first LiMAx test and ICG-PDR were carried out within the first 24 hours after onset of septic symptoms, followed by day 2, 5 and 10. Other biochemical parameters and scores determining the severity of illness were measured daily. Clinical outcome parameters were examined after 90 days or at the end of treatment. The population was divided into 2 groups (group A: non-survivors or ICU length of stay (ICU-LOS) >30 days versus group B: survivors and ICU-LOS <30 days) for analysis. Epidemiological baseline characteristics of both groups were similar. Group A patients had significant lower LiMAx and ICG-PDR values than patients in group B. Determination of ICG-PDR by finger probe failed in 14.3% of tests due to insufficient peripheral pulses. Respiratory, renal and hepatic dysfunction (LiMAx and ICG-PDR) were associated with prolonged ICU-LOS. Only LiMAx <100 μg/kg/h and respiratory dysfunction were associated with increased mortality. For LiMAx <100 μg/kg/h receiver operating characteristic-analysis revealed a 100% sensitivity and 77% specificity for death. Sepsis-related hepatic dysfunction can be diagnosed early and effectively by the LiMAx test. The extent of LiMAx impairment is predictive for patient morbidity and mortality. The sensitivity and specificity of the LiMAx test was superior to that of ICG-PDR regarding the prediction of mortality.