Ultrafiltration and clearance studies in human isolated peritoneal vascular loops

Eight samples of human peritoneal tissue were obtained from patients undergoing hemicholectomy for cancer. An artery and a vein were cannulated and perfused with blood in vitro with a special circuit able to provide different perfusion pressures. Ultrafiltration and clearance studies were performed in these samples. Both ultrafiltration and small-solute clearances linearly correlated with the blood flow, demonstrating a strong dependence on this parameter. The peritoneal capillary showed a typical filtration pressure equilibrium with a constant filtration fraction at different blood flows. The results suggest that the blood flow may be a factor limiting the efficiency of peritoneal dialysis both in terms of mass transfer coefficients and maximal ultrafiltration rates.