Abstract
Roller pump has been used as a standard flow-generator in various extracorporeal circulation (ECC) systems, however, it has a critical problem that a sudden stenosis or occlusion of a blood-stream line can result in an excessive high or negative pressure in the circuit. To avoid this hazardous accident, we've developed a device which regulates the rotation of a roller pump according to the blood circuit pressure. We designed this device to use with CAPS Roller Pump type 10-10-00 (Stoeckert instrumente GmbH., Munich, Germany), which has an auxiliary signal input port to regulate the rotation of a pump. Our device has four beneficial features: no alteration is necessary for a roller pump itself; two pressure points where the device begins to regulate the rotation of a pump (pressure ‘S’) and stops it completely can be freely set; between these two pressure points (range ‘W’), the rotation of a pump is inversely regulated to the blood circuit pressure; the device can also respond to the negative pressure in the blood circuit. We evaluated our device using a model ECC circuit. The pump charactericity of the ECC system with our device until the circuit pressure reached the pressure ‘S’ was mimic to that of the ordinary roller pump system, whereas, during the range ‘W’, to that of a centrifugal pump system. In conclusion, our device can provide a safe management of ECC without any critical sharp fluctuation in the blood circuit pressure.
