Influence of zero-balanced hemofiltration on the course of severe experimental pancreatitis in pigs.

OBJECTIVE: To examine the impact of continuous venovenous hemofiltration (CVVH) on the course of experimental pancreatitis in pigs. SUMMARY BACKGROUND DATA: The activation of different mediator cascades is assumed to trigger multiple organ dysfunction or failure during necrotizing pancreatitis. CVVH has been suggested to be beneficial in those instances by eliminating several inflammatory mediators released in the circulation.
METHODS: Pancreatitis was induced by a combined intraductal injection of sodium taurocholate and enterokinase. Control group animals received no treatment after induction. A second group underwent "therapeutic" CVVH after a 20% decline of mean arterial pressure. In the third group, "prophylactic" CVVH was started simultaneously with the induction of pancreatitis. The concentrations of tumor necrosis factor-alpha, transforming growth factor-beta1, kinin, and phospholipase A2 were measured at different time points in blood (pre- and postfilter) and in the hemofiltrate to calculate the respective sieving coefficients that reflect most accurately the plasma clearance of mediators by CVVH.
RESULTS: Survival time was significantly prolonged both by therapeutic and prophylactic CVVH; it was more pronounced in the latter. CVVH did not influence the increase in transforming growth factor concentrations. However, 6 hours after induction, the increases of plasma concentrations of tumor necrosis factor, phospholipase, and kinin were significantly weakened by CVVH compared with controls. In the treatment groups, the plasma concentrations of tumor necrosis factor and phospholipase showed a significant negative correlation with the respective sieving coefficients, which decreased in the later course of the experiments.
CONCLUSIONS: Experimental necrotizing pancreatitis was associated with a tremendous increase of plasma concentrations of tumor necrosis factor, phospholipase, and kinin. The effective removal of these mediators by CVVH resulted in significantly improved survival time. Animals that received prophylactic CVVH had a longer survival period than those in which CVVH was started after clinical impairment. The decreasing efficiency of CVVH in eliminating inflammatory mediators in the later course of the experiments suggested that the filter membranes were compromised by long-term application. These findings provide further evidence that CVVH offers therapeutic options even in the absence of conventional indications for blood-purifying treatments.