Abstract
Single needle dialysis (SND) is inferior to double needle dialysis in efficiency because it is always accompanied by ineffective flow (IF) and recirculation that become greater when switchings of the A and V phases (S of A-V) are increased. IF is caused by the skidding of the blood pump and dead space. In the experiment with city water, IF became increased with rise of the intended flow. This tendancy was more clearly represented in the condition that maximal V pressure was stipulated lower. We designed a new circuit with volume reservoir (VR) which is composed of two parts: inner part is a balloon to store fluid and outer part is a pipe to prevent the rupture of the balloon. The balloon part of VR is made of raw rubber or latex rubber. Three types of VR length are follows: 10cm, 15cm and 20cm. The circuit with VR was able to decrease S of A-V and IF in SND.
