VCM
Ventilation Control Module type
The HSE Ventilation Control Module (VCM) has been developed
especially for producing a negative pressure at a respiratory rhythm as
required for operating an isolated perfused rat, guinea-pig, or mouse lung.
The module operates with a positive pressure. The negative pressure required
for ventilation is generated by means of a venturi nozzle which is fitted
externally. When used with a restrictor nozzle the module can also be employed
for positive pressure ventilation during the preparation phase of the lung,
a very convenient facility. The VCM module works independently; it requires
neither a vacuum nor a compressed air supply. The module consists of an
electronic and a pneumatic section. A low-noise pump stores the compressed
air in a small reservoir where it is stabilised electronically. The air
stream which appears at the outlet connection (TO VENTILATION HEAD) passes
through adjustable valves. The air is controlled electronically according
to the selected respiration rate (RATE) and the selected inspiration cycle
(INSP. CYCLE%). In addition one (or several) deep breaths (DEEP INSPIRATION)
can be triggered by pressing a button. The output therefore consists of
a rhythmically modulated air stream at a positive pressure. By connecting
it to a suitable nozzle a rhythmically modulated negative or positive pressure
of the desired magnitude can be produced.
The real ventilation curve depends on the characteristics of the venturi
or restrictor nozzle and the volume of the negative pressure lung chamber.
All technical data refer to our isolated perfused lung setup Type 829.
In our endeavor to build a completely electronically controlled artificial
respiration ventilator we are now working on a specially designed restrictor
nozzle to use the VCM module as a ventilator for small animals such as mouse,
rat or guinea-pig (Please ask for detailed information).
