Haemonetics MCS+, Operator And Maintenance Manual

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3-6 Disposables
P/N 39551-00, Rev. F
Once the buffy coat is detected by the Bowl Optics sensor, plasma from the plas-
ma bag is rapidly surged through the bowl.
The surging plasma quickly flows to the bottom outside edge of the spinning
bowl. The plasma passes through the cell layers and increases the separation be-
tween them. The platelets, which are lighter, flow out of the bowl with the plas-
ma while the heavier cells remain in the bowl.
Once collection is completed, the bowl stops spinning. Due to the loss of cen-
trifugal force, the blood remixes.
When the bowl is spinning, it appears to be full. However, all Haemonetics
bowls are designed with an inner core in which some sterile air is trapped during
centrifugation. Once the bowl stops, the volume of blood within the processing
chamber settles to the bottom and displaces the sterile air that was trapped within
the inner core. This causes the stationary bowl to appear to be only two-thirds
full.
Figure 3-4, Surge Elutriation
Plasma
Platelets and Plasma
Buffy Coat