Abstract: Objective To investigate the characteristics of ultrasonic renal perfusion indexes in patients with cirrhotic ascites and relationship between intra-abdominal pressure and renal resistance index. To investigate the influence of ascites discharge on intra-abdominal pressure, systemic hemodynamics and renal perfusion. Methods Patients with cirrhotic ascites and intra-abdominal hypertension were included, with an average age of 18-70 years. Patients with chronic renal failure and other causes that interfered with abdominal ultrasonography were excluded. A total of 21 cases were included in the study. Color Doppler ultrasonography was used to measure the renal blood perfusion index. Direct peritoneal puncture manometry was used to measure peritoneal pressure. Intra-abdominal pressure, systemic hemodynamic indexes, and renal blood perfusion parameters were recorded and analyzed at 4 time nodes: before discharging ascites, cumulative release of ascites 2500 ml, 5000ml and 7500ml, respectively. Pearson correlation analysis was used to analyze the relationship between intra-abdominal pressure and the renal resistance index. Self-control design was used to analyzed the effect of massive ascites drainage on systemic hemodynamics and renal perfusion. Results Abdominal hypertension was obvious in patients with cirrhosis and ascites. The median intraperitoneal pressure was 18 (15.5-21) cmH₂O. Renal artery resistance index (RI) generally increased, the median intraperitoneal RI was 0.727 (0.72-0.755). There was a moderate correlation between the intra-abdominal pressure and the renal resistance index (r=0.491, P＜0.001). Intraperitoneal pressure could be significantly reduced after ascites discharge. The median intraperitoneal pressure before discharging ascites and cumulatively discharging ascites 7500 mL were 18 (15.5-21) cmH₂O and 12 (9.5-13.5) cmH₂O, H=26.584, P＜0.001. As intra-abdominal pressure decreases, there was a downward trend for the mean arterial pressure. The mean arterial pressure before discharging ascites and cumulatively discharging ascites 7500 mL were 81 (77-90) mmHg and 76 (75-81) mmHg, H=8.767, P=0.033. The renal resistance index decreased significantly with the decrease of intra-abdominal pressure. The average RI before discharging ascites and cumulatively discharging ascites 7500 mL were 0.727 (0.72-0.755) and 0.641 (0.623-0.66), H=64.104, P＜0.001.Conclusion There is a correlation between intra-abdominal pressure and the renal resistance index. Discharging ascites can improve peritoneal hypertension and the renal artery resistance index in cirrhotic patients with ascites.

Key words: Drain ascites, Liver cirrhosis, Intra-abdominal pressure, Doppler ultrasound, Renal perfusion