Progav 2.0 Operating Principle - MIETHKE proGAV 2.0 Manuel Du Patient

proGAV 2.0 operating principle

A proper understanding of the operating principle of proGAV 2.0 requires
a brief look at the physical framework conditions that such drainage invol-
ves: creating a link between these two systems - ventricle and abdominal
cavity - might allow the CCSF to drain without control, particularly when
the patient stands upright, thus transporting too much of the fluid from the
ventricles to the abdominal cavity. This is called overdrainage and must
be prevented by all means. However, is it is entirely normal for a mobile
human being to change position frequently: to stand up, walk, sit down
or lie down. All this results in continuous physical changes in the drainage
system.
In order to achieve a controlled drainage of the cerebrospinal fluid, a val-
ve such as proGAV 2.0 is implanted together with the tube system. This
combination of a tube system and a valve is known as a shunt system.
Ideally, a valve such as proGAV 2.0 ensures that CSF is only drained off
when the pressure inside the ventricles becomes too high. To that end,
the valves have pre-set or settable opening pressures, i.e. a valve opens
once a predefined intracranial pressure has been reached, thus preventing
over- or underdrainage. However, the optimum opening pressure in a pro-
ne position is not the same as in an upright one. This is the consequence
of the physical laws of gravity (gravitation).
Physical background
Two interlinked fluid-filled vessels that are - as in a prone person - horizon-
tal to each other aim to balance each other. If the valve has the same ope-
ning pressure in the upright position, too much fluid will drain. This equates
to a low opening pressure.
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// 2.0 PATIENT MANUAL //
proGAV EN