Renal resistive index and renal function before and after paracentesis in patients with hepatorenal syndrome and tense ascites

To assess the effect of reducing intra-abdominal pressure (IAP) by paracentesis on renal resistive index (RI), hemodynamics and renal function. Uncontrolled trial in a university gastroenterological intensive care unit. Twelve spontaneously breathing cirrhotic patients with hepatorenal syndrome, tense ascites and a clinical indication for paracentesis. Paracentesis and substitution of albumin. Hemodynamic variables were assessed by transpulmonary thermodilution, RI was determined by Doppler ultrasound of renal interlobar arteries. After paracentesis and albumin substitution, there was a significant decrease of IAP (20 mmHg (19-22) to 12 mmHg (10-13), systemic vascular resistance index (from 1,243 dyn s/cm⁵/m² (1,095-1,745) to 939 dyn s/cm⁵/m² (812-1,365); p = 0.005) and RI (from 0.848 (0.810-0.884) to 0.810 (0.780-0.826); p = 0.003). Arterial compliance increased from 1.33 mL/mmHg (0.89-1.74) to 1.71 mL/mmHg (1.21-2.12), pulse pressure index remained unchanged. Creatinine clearance (ClCreat) increased significantly from 5 mL/min (0-28) to 9 mL/min (0-36) (p = 0.018) and urinary output from 12 mL/h (0-49) to 16 mL/h (0-64) (p = 0.043). In patients with cirrhosis, HRS and tense ascites, IAP may contribute to renal dysfunction. Reduction of IAP following paracentesis and albumin substitution may improve ClCreat, probably by improving renal blood flow as reflected by decreasing RI in Doppler ultrasound.