Correlation of Liver Perfusion with Outcome of Patients with Severe Liver Disease – A Prospective Cohort Study

Chronic liver disease is one of the major causes of morbidity and mortality worldwide. Pathophysiologically, inflammatory processes lead to hepatocellular damage and fibrosis of liver tissue. Intrahepatic resistance increases, resulting in a change in the hemodynamics of hepatic blood vessels. The ultrasound examination plays an important role in the evaluation of liver diseases. However, the precise role and prognostic value of routine Doppler sonography of liver perfusion in patients with severe liver disease has not been sufficiently examined. The aim of this study is to determine a correlation of hepatic perfusion with outcome of patients with severe liver disease in the context of intensive care treatment.

Fifty patients hospitalized with severe liver disease in the internal intensive care unit of the Department of Internal Medicine I of the University Hospital Regensburg were routinely examined with sonography twice a week. To quantify liver perfusion, the hepatic artery resistance index (HARI) and the maximum portal vein velocity (PVv) were determined by means of Doppler ultrasound. At the time of the study, the MELD (Model for End-Stage Liver Disease) score was calculated for each patient. In addition, clinical data such as the current catecholamine dose, the mean arterial blood pressure, ventilation and laboratory parameters were collected. Finally, the duration of intensive care treatment and the outcome of the patients were also correlated with sonographic parameters.

By analyzing the obtained parameters of the MELD score, the HARI and the maximum PVv in a scatter plot a linear, positive correlation between HARI and MELD score and a linear, negative correlation between maximum PVv and MELD score were shown. Initial regression analyses quantify these correlations with a R2-value of 0,220 (HARI – MELD score) and 0.078 (PVv – MELD score). Furthermore, it appeared that the HARI in patients who died during inpatient treatment increased on average by 1.6% with each examination, whereas it declined by 0.3% in non-deceased patients. On average, with each examination the maximum PVv increased by 1.8% in deceased patients and by 16.5% in non-deceased study participants.

The correlation of HARI and maximal PVv with the MELD score shows that the development of liver perfusion is a prognostic factor. The routine assessment of HARI and the maximum PVv in patients with severe liver disease in the ICU should be further evaluated.