Ascites is a major complication of decompensated liver cirrhosis. Intraabdominal hypertension and structural alterations of parenchyma involve decisive changes in hepatosplanchnic blood flow. Clearance of indo-cyanine green (ICG) is mainly dependent on hepatic perfusion and hepatocellular function. As a consequence, plasma disappearance rate of ICG (ICG-PDR) is rated as a useful dynamic parameter of liver function. This study primarily evaluates the impact of large-volume paracentesis (LVP) on ICG-PDR in critically ill patients with decompensated cirrhosis. Additionally, it describes influences on intraabdominal pressure (IAP), abdominal perfusion pressure (APP), hepatic blood flow, hemodynamic and respiratory function.

We analyzed LVP in 22 patients with decompensated liver cirrhosis. ICG-PDR was assessed by using noninvasive LiMON technology (Pulsion® Medical Systems; Maquet Getinge Group), and hepatic blood flow was analyzed by color-coded duplex sonography.

Paracentesis of a median volume of 3450 mL ascites evoked significant increases of ICG-PDR from 3.6 (2.8–4.6) to 5.1 (3.9–6.2)%/min ( p   <  0.001). Concomitantly, we observed a raise in “ICG-Clearance” from 99 (73.5–124.5) to 104 (91–143.5) mL/min/m ² ( p  = 0.005), while circulating blood volume index was unchanged [2412 (1983–3025) before paracentesis vs. 2409 (1997–2805) mL/m ² , p  = 0.734]. Sonography revealed a significant impact of paracentesis on hepatic blood flow: Hepatic artery resistance index dropped from 0.74 (0.68–0.75) to 0.68 (0.65–0.71) ( p   <  0.001) and maximum flow velocity in hepatic vein increased from 24 (17–30) to 30 (22–36) cm/s ( p   <  0.001). Consistent with previous studies, paracentesis caused significant decreases in IAP from 19.0 (15.0–20.3) to 11.0 (8.8–12.3) mmHg ( p   <  0.001) and central venous pressure from 22.5 (17.8–29.0) to 17.5 (12.8–24.0) mmHg ( p   <  0.001) with inverse increases in APP from 63.0 (56.8–69.5) to 71.0 (65.5–78.5) mmHg ( p   <  0.001). Changes in ICG-PDR were concomitant with changes in IAP ( r  = − 0.602) and APP ( r  = 0.576). Moreover, we found a substantial improvement in respiratory function. By contrast, hemodynamic parameters assessed by transpulmonary thermodilution, serum bilirubin and international normalized ratio did not change after paracentesis.

Critically ill patients with decompensated cirrhosis and elevated IAP showed dramatically impaired ICG-PDR. Paracentesis evoked an improvement in ICG-PDR in parallel with a decreased IAP and an increased APP, while conventional parameters of liver function did not change. This effect on ICG-PDR is mainly referable to a relief of intraabdominal hypertension and changes in hepatosplanchnic blood flow.