HEMODYNAMIC-EFFECTS OF ARTERIOVENOUS AND VENOVENOUS HEMOFILTRATION INPIGLETS

The aim of this study was to compare the early haemodynamic effects of continuous arteriovenous haemofiltration (CAVH) with those of continu ous venovenous haemofiltration (CVVH) in normal and endotoxic piglets, within the framework of a two-period cross-over trial. Sixteen domest ic piglets (weight 6-18 kg) underwent 1 h of CAVH followed by 1 h of C VVH or 1 h of CVVH followed by 1 h of CAVH. Six were pre-treated with a graded endotoxin infusion to simulate clinical sepsis. The main meas urements included: heart rate; mean arterial (MAP), pulmonary artery, central venous and pulmonary artery occlusion pressures; thermodilutio n cardiac output; and calculated systemic (SVRI) and pulmonary vascula r resistance indexes. Each measurement was performed immediately befor e and 30 min after commencement of each technique of filtration. Comme ncement of haemofiltration in normal piglets caused minimal haemodynam ic effects. In endotoxic piglets, commencement of filtration, whether CAVH or CVVH, caused a haemodynamic change which was significantly mor e pronounced in the first filter (SVRI -39%. MAP -32%) than the second filter (SVRI +22%, MAP +0.9%) (SVRI, P=0.01, first filter vs. second) (MAP, P=0.009 first filter vs. second). In conclusion, there were no significant differences between the early haemodynamic effects of CAVH and CVVH in normal or endotoxic piglets. The haemodynamic effects of either technique may become more significant in the presence of sepsis .