초록 ▼

A single needle batch-type blood fractionation system for separating plasma from whole blood includes a disposable flow system having a single-lumen phlebotomy needle and associated donor conduit, a flow-through plasma separation filter, and an in-process fluid reservoir. During an initial draw cycl

A single needle batch-type blood fractionation system for separating plasma from whole blood includes a disposable flow system having a single-lumen phlebotomy needle and associated donor conduit, a flow-through plasma separation filter, and an in-process fluid reservoir. During an initial draw cycle whole blood is pumped through the filter to the in-process reservoir by a peristaltic-type inlet pump operating at a predetermined draw rate. When a predetermined volume of filtered plasma-deficient blood has been collected in the reservoir, as sensed by the weight of the reservoir, the system reverts to a return cycle wherein a portion of the plasma-deficient blood in the reservoir is pumped back to the donor conduit by a peristaltic-type return pump operating at a predetermined return rate higher than the draw rate of the inlet pump. Depending on the relative operating speeds of the inlet and return pumps, an operator-controllable portion of the plasma-deficient blood from the in-process reservoir is returned to the donor through the phlebotomy needle, and the remaining portion is recirculated through the filter. The partial recirculation of plasma-deficient blood through the filter during the return mode reduces the processing time of the system, provides for improved accommodation of whole blood of unusually high or low hematocrit, and enables the use of a smaller and less expensive filter.

대표청구항 ▼

The method of separating a blood component from whole blood, utilizing a single lumen phlebotomy needle, and flow-through blood separating means, comprising the steps of: continuously pumping in whole blood drawn from a donor through the single lumen of the needle through the separation means to con

The method of separating a blood component from whole blood, utilizing a single lumen phlebotomy needle, and flow-through blood separating means, comprising the steps of: continuously pumping in whole blood drawn from a donor through the single lumen of the needle through the separation means to continuously separate the blood into a desired blood fraction component and a fraction-depleted blood component; continuously collecting the fraction-depleted blood component from the separation means in a reservoir; intermittently pumping back a volume of the fraction-depleted blood component from the reservoir toward the single lumen needle by initiating said pumping back step when the volume of the fraction-depleted blood component in the reservoir rises above a predetermined maximum level and by terminating said pumping back step when the volume of the fraction-depleted blood component in the reservoir returns to a predetermined minimum level; and maintaining said pumping back step at a higher rate than said pumping in step to return, during said pumping back step, a first portion of the intermittently pumped volume of the fraction-depleted blood component to the donor through the single lumen needle while recirculating a second portion of the intermittently pumped volume of the fraction-depleted blood component back through the separation means along with the whole blood which is being continuously pumped therethrough.