Abstract
The clinical studies of hemofiltration were done on the points of clinical application and its effectiveness. Sieving coefficient was approximately 1.0 for low molecular substances such as urea and creatinine to inulin with molecular weight of 5, 000 daltons. The extraction rate for urea, creatinine, uric acid and phosphate was more than 40%, respectively, when 20l of body fluid was exchanged. Serum electrolytes and blood gas were also normalized to the desirable levels.
Fourteen patients with chronic renal failure were on hemofiltration, and 8 of them had been on hemofiltration more than 18 months. Hemofiltration was done in postdilution mode, 3 times weekly. Two of Filtryzer B-1 (polymethylmethacrylate, 1.35m2, hollow fiber artificial kidney, Toray) in series were employed for hemofilter. Equalizing systems between filtrate and substitution fluid were volume-controlled NY-II (Nipro) and weight-controlled M-5, 000 (Toray). Composition of substitution fluids was Na 135-140mEq/l., K 2.0mEq/l, Cl 104.75-107.3mEq/l, Ca 3.5-3.8mEq/l., Mg 1.5mEq/l, respectively, and acetate 40mEq/l or lactate 37.5-38mEq/
The patients with symptoms of dialysis disequilibrium syndrome during hemodialysis were tolerable to hemofiltration without symptom. Anephric patients required less blood transfusion in hemofiltration than in hemodialysis. A patient suffered from pain in the eye because of glaucoma recieved painless treatment on hemofiltration. Not only depletion syndrome but also other side effects called in question did not appear in 14 patients.
Solute kinetics using 22Na were studied in hemofiltration in comparison with hemodialysis. Two groups of patients were selected to make study, hemofiltration and hemodialysis group. It took more than 12 hours for equilibrium after oral administration of 22Na. The concentrations of Na and 22Na in serum were measured every an hour during procedures, and total removal amount of 22Na was compared between two groups.
Hemofiltration could remove significantly larger amount of 22Na than hemodialysis although body weight loss was comparable between two groups. On the other hand the disappearance curve of serum 22Na concentrations was significantly delayed in hemofiltration more than in hemodialysis. But Na concentration in serum was not changed significantly during procedure in both groups. It is also noted that a decrease of plasma osmolarity was steeper during hemodialysis than hemofiltration. These results indicate that 22Na in hemofiltration can move between fluid spaces more promptly and smoothly than in hemodialysis, suggesting more efficient removal of intracellular fluid.
