Quantitative modeling of the physiology of ascites in portal hypertension

Abstract

Although the factors involved in cirrhotic ascites have been studied for a century, a number of observations are not understood, including the action of diuretics in the treatment of ascites and the ability of the plasma-ascitic albumin gradient to diagnose portal hypertension. This communication presents an explanation of ascites based solely on pathophysiological alterations within the peritoneal cavity. A quantitative model is described based on experimental vascular and intraperitoneal pressures, lymph flow, and peritoneal space compliance. The model's predictions accurately mimic clinical observations in ascites, including the magnitude and time course of changes observed following paracentesis or diuretic therapy.

Use of ultrasound findings to predict bowel ischemic changes in pediatric patients with intestinal volvulus

“…Although the presence of ascites was statistically associated with bowel ischemic changes, there were some reports of physiologic ascites . Therefore, ascites due to volvulus may be difficult to differentiate from physiologic ascites.…”

“…Although the presence of ascites was statistically associated with bowel ischemic changes, there were some reports of physiologic ascites. [27][28][29] Therefore, ascites due to volvulus may be difficult to differentiate from physiologic ascites. However, echogenic ascites is an important indicator for surgical interventions in neonates with necrotizing enterocolitis.…”

Hepatic transudation barrier properties

“…Therefore, it can be inferred that hepatic transudation was primarily driven by the hydrostatic pressure gradient under the experimental conditions. In a closed abdomen under normal conditions, however, protein concentration in the peritoneal fluid is lower than that in the plasma . As a result, the hepatic transudation rate in vivo with a closed abdomen may be lower.…”

“…The transudation rate and transudation barrier properties for the entire liver have not been quantified. Given the limitations to experimental approaches, several investigators have begun to use computational modeling to explore the complex interactions that govern hepatic interstitial and peritoneal fluid balance . Despite the recognition that hepatic transudation plays a critical role in hepatic interstitial and peritoneal fluid balance, hepatic transudation has not been explicitly introduced into computational approaches.…”

“…Despite the recognition that hepatic transudation plays a critical role in hepatic interstitial and peritoneal fluid balance, hepatic transudation has not been explicitly introduced into computational approaches. The lack of data characterizing the key properties governing transudation from the entire liver has led several investigators to assume that hepatic transudation is negligible or constant or to assume that transudation has no effect on hepatic interstitial fluid balance and hepatic lymph flow . Therefore, the goal of the present work was to provide the first direct measurement of the hepatic transudation rate and transudation barrier properties under conditions relevant to ascites formation.…”