If you now simulate a patient standing up by holding the vessel simulating
the ventricles much higher than that representing the abdominal cavity, the
fluid tries to follow gravity and drain downwards. The height of a patient has
a significant impact on the length of the water column being created in the
catheter in the upright position, and also on the suction effect. The valve
previously set to a low pressure now opens at a low opening pressure in
the upright position, too, thus ensuring that excessive cerebrospinal fluid
drains down while the patient is upright.
A single opening pressure would be a constant compromise between the
lying and the upright body position and would constitute a serious restric-
tion to the quality of life.
This means that different opening pressures are required for the various
body positions. As a result, an SA 2.0 is offered as an additional valve in
order to provide a higher opening pressure in an upright body position.
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SA 2.0 PATIENT MANUAL //