Effect of long‐term increase in the frequency and/or prolongation of dialysis duration on certain clinical manifestations and results of laboratory investigations in patients with chronic renal failure

The effects of dialysis frequency increase by one weekly and prolongation of dialysis duration by a mean of 17.5% on certain clinical manifestation and results of laboratory investigations were studied in a group of 14 patients treated with haemodialyses because of chronic renal failure caused by isolated renal diseases. Haemodialyses were carried out using a RSP Travenol artificial kidney and Ultra Flo 145 dialysers. The blood flow was always 200 ml/min and the flow of dialysing fluid was 500 ml/min. One dialyser was used repeatedly during 3 weeks in the same patients. After increasing the frequency or duration of dialyses the patients were not given transfusions of blood donors. The mean length of observation after increasing the frequency of dialyses was 6.4 months and after increasing their duration this length was 6.9 months. The change in the mode of dialysis had no significant effect on the concentration of urea and creatinine before as well as after dialysis. The increase in the frequency of dialyses caused a significant rise in the value of haematocrit by nearly 4%, a rise in the serum albumin concentration by a mean of 0.45 g/100 ml; a mean rise in the velocity of nerve conduction by over 6% of the lower normal range, and a mean rise in dry body weight by nearly 3.5 kg. Prolongation of dialysis time caused a significant mean rise in the haematorcrit value by over 1% before dialysis and in the serum albumin level by a mean of 0.30 g/100 ml. Both, the increase in the frequency and in the duration of dialyses caused a fall in the arterial blood pressure in hypertensive patients. The very favourable effects of increased frequency of dialyses on the clinical state of patients and on important laboratory parameters suggests that in near future the basic form of treatment of chronic renal failure may be daily short‐lasting haemodialysis.