Automation of plasma sequestration

A system for plasma sequestration from red blood cells in whole blood in a centrifuge apparatus to produce a separated plasma having a desired cumulative hematocrit or a desired cumulative platelet harvest, said system having in sequence a fill cycle, during which whole blood is supplied to said centrifuge, said plasma is separated from said red blood cells such that a red cell pack is formed in said centrifuge and said separated plasma is collected, and an empty cycle, during which said separated blood cells remaining in said centrifuge are removed therefrom and collected, which comprises:

• means for supplying a controlled flow of whole blood to said centrifuge;
• means for monitoring the volume of whole blood supplied to said centrifuge;
• means for collecting said separated plasma;
• means for removing and collected said separated red blood cells;
• means for determining the volume of whole blood, V.sub.m, that was supplied to said centrifuge to generate a predetermined fixed volume of red blood cell pack in said centrifuge;
• means for controlling the rotational speed of said centrifuge;
• control means for terminating said fill cycle and thereafter initiating said empty cycle actuated when the monitored volume of whole blood being supplied to said centrifuge equals a calculated maximum fill volume, V.sub.f ;
• automated means for calculating said maximum fill volume, V.sub.f, operatively associated with said control means, said volume monitoring means and said means for determining V.sub.m, which employs an empirically predetermined equation relating V.sub.m to V.sub.f, where said equation is determined in trial plasma sequestrations where V.sub.f is selected as the centrifuge fill volume that results in separated plasma having a desired cumulative hematocrit or a desired platelet harvest.