Sensitivity and specificity of plasma disappearance rate of indocyanine green as a prognostic indicator in acute liver failure

Background In patients presenting with acute liver failure (ALF) prediction of prognosis is vital to determine the need of transplantation. Based on the evidence that plasma disappearance rate of indocyanine green (ICG-PDR) correlates with liver cell function, we evaluated the ability of ICG-PDR measured by pulse dye densitometry to predict outcome in patients with acute liver failure. Methods Prospectively markers of hepatocellular injury, synthesis and excretion, including ICG-PDR were measured daily until liver transplantation, death, discharge from intensive care unit, or up to 7 days in 25 patients with acute liver failure. Receiver operating curve (ROC) analysis was performed to assess the value of ICG-PDR to predict outcome in ALF. Results The 25 patients analyzed included 18 that recovered spontaneously and 7 that underwent liver transplantation (n = 6) or died (n = 1). Causes of ALF included viral hepatitis (n = 4), toxic liver injury (n = 15), ischemic liver injury (n = 2), and cryptogenic liver failure (n = 4). King's college criteria were fulfilled in 85.7% of patients not recovering spontaneously and in 16.7% of patients recovering spontaneously. The mean ICG-PDR measured on day 1 in patients recovering spontaneously was 12.0 ± 7.8%/min and in patients not recovering spontaneously 4.3 ± 2.0%/min (P = 0.002). By ROC analysis the sensitivity and specificity of an ICG-PDR value ≤ 6.3%/min on study day 1 were 85.7% and 88.9%, respectively, for predicting a non spontaneous outcome in ALF. Conclusion ICG-PDR allows early and sensitive bedside assessment of liver dysfunction in ALF. Measurement of ICG-PDR might be helpful in predicting the outcome in acute liver failure. Trial registration Clinicaltrials.gov, NCT 00245310