tokens: Long-term chronic dialysis , however , the highest standards should be applied to these children to preserve their future `` cardiovascular life '' —which might include more dialysis time and on-line hemodiafiltration online hdf with synthetic high flux membranes with the surface area of 0.2sq.m to 0.8sq.m and blood tubing lines with the low volume yet large blood pump segment of 6.4/8.0mm , if we are able to improve on the rather restricted concept of small-solute urea dialysis clearance .