Conventional single needle system which has a few disadvantages as follows.
1) It is difficult to settle blood flow and ultrafiltrate pressure constantly.
2) Intravascular pressure changed in a wide range of punctured sites.
3) This system with special equipment regulating blood flow is expensive.
We have developed a new strategy with only advantages of single needle system. The principle is to control blood flow, pressing on and off the housing of blood line by a plate.
Result of our clinical experiment with the system was satisfactory.
