Gambro COBE 2991, Essentials Manual

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1-6 COBE 2991 Cell Processor • Essentials Guide
Introduction
The valves are normally in the closed position, but can be programmed to open
during automatic operation. Alternatively, they can be opened and closed manually
using the VALVE SELECTOR control during manual operation or when loading
the cell processing set.
Red Cell Detector
The red cell detector (RCD) is an optical sensor that uses infrared light to detect the
presence of red blood cells (RBCs) in fluids expressed at certain times during cell
processing (Figure 1-4). The RCD is validated and calibrated to detect RBCs only.
Other cells may or may not be detected by the RCD.
On COBE 2991s with five valves, the RCD is active when the supernatant-out
valve (SOV) is selected and is deactivated when the collect valve is selected.
On COBE 2991s with four valves, the RCD cannot be deactivated. To prevent the
RCD from detecting RBCs (or potentially other types of cells), remove the clear
tubing between the rotating seal and the manifold junction from the RCD as
directed by your protocol.
During processing in the Automatic mode (with the SOV selected on machines
with five valves), the presence of RBCs either advances the COBE 2991 from the
Supernatant-Out operation to the Agitate/Wash-In operation or ends the
procedure. During processing in the Manual mode, the presence of RBCs halts the
Supernatant-Out operation but does not advance the COBE 2991 to the next
operation.
Figure 1-4: Red cell detector (shown with five valves)
Centrifuge
The centrifuge (Figure 1-5) consists of the centrifuge bowl and a removable
transparent cover that allows for loading of the cell processing bag and visual
observation of cell separation. A flexible diaphragm, located in the bottom of the
centrifuge bowl, inflates when hydraulic fluid is pumped underneath it. When
inflated, the flexible diaphragm pushes against the bottom of the cell processing
Red cell detector