Measurement and analysis of flow and pressure in tubes during single-needle dialysis

Abstract

We have fabricated a model for simultaneous measurement of flow rate and pressure in tubes with synchronous picture acquisition of the roller position of a hemodialysis pump operated in a single-needle (SN) mode. A solution of 40 wt% sucrose was perfused. In an SN mode, three phases (removal: inflow; stop; retransfusion: outflow) were observed. As the rollers stopped at arbitrary positions, flow rate varied accordingly. In addition, a reverse flow was observed due to some lag between pump movement and changes in flow and pressure. By minimizing the time lag and reverse flow, optimized operations may be achieved.