Single Two-Lumen Cannula Dialysis

The single needle dialysis system developed by Kopp et al. has some disadvantage of using costly solenoid clamp, necessary for the shift of blood flow in the dialyzer circuit. The present authors have devised a single two-lumen cannula system to overcome this disadvantage. It is possible to operate this system without the solenoid clamp and also to enhance the dialytic effect. In the single two-lumen cannula, two needles, semicircular in cross section, are arranged contiguous to each other so as to form a single cannula, circular in cross section. The tip orifices of the two needles are 1.7 cm apart in order to prevent the mixture of inflowing and outflowing blood. At their bases the needles are connected, one to the inflow and the other to the outflow line. Clinical trials of the new dialysis system have given positive results. The system has been found to be simple in operation, safe and effective. Its use is recommended for routine chronic hemodialysis.