[Single-needle hemodialysis].

In 10 patients on chronic dialysis a new hemodialysis technique, in which the extracorporeal and patient circulations are connected by controlled bloodflow reversal using a single cannula, has been compared with the conventional two-needle method. For two control periods (two-needle dialysis) and an intermediate test period (one-needle dialysis) involving 12 hemodialyses in each case, clinical, biochemical and hematolgic values and extracorporeal hemodynamic findings were studied. During the one-needle dialysis period the incidence of dialyzer membrane ruptures or muscular cramps, body weight, blood pressure, neurologic status, serum electrolytes and uric acid, and hemolysis rates, remained unchanged. There was however a diminution of dialysis effectiveness due to a significant bloodflow reduction of 26 percent (p less than 0.001) and extracorporeal blood recirculation of 6-54 percent. Correspondingly, there was a slight rise in the pre- and post-dialysis values for serum creatinine and urea nitrogen (p less than 0.0125). The observed reduction in effectiveness with one-needle dialysis can presumably be compensated by the use of systems with low recirculation and a correspondingly longer dialysis time. If these conditions are fulfilled, one-needle dialysis is a technically acceptable procedure which is comparatively easy to carry out and involves markedly less discomfort for the patient than the conventional two-needle method.