SLE 2000, Руководство пользователя

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2. Principles of Operation SLE2000 Valveless System*
The patient circuit is supplied with a constant fixed flow of 5LPM fresh gas. This gas
comes from the internally mounted oxygen blender and its concentration is also
monitored by a fuel cell and displayed on the FlO
2
digital display. This fresh gas
supply is then passed through a humidifier to the inspiratory port of the patient ET
connector. Built into the ventilator are circuits to detect either a gas flow failure or a
tubing blockage. The patient circuit requires a restrictor fitted into the inspiritory port.
Therefore, only SLE approved patient circuits must be used.
The Expiratory limb of the patient circuit is connected to the Exhalation port on the
ventilator. This consists of a removable block mounted on a manifold, accessed by
lowering the left hand side cover. The expiratory manifold has two nozzles. The front
one to generate CPAP/PEEP and is supplied via the CPAP regulator on the front
panel of the Pneumatic Module. The rear one to generate peak inspiratory
pressure(PIP).
To avoid the possibility of gas dilution these regulators are supplied with the same
oxygen concentration as the Fresh Gas supply . The front nozzle is used to generate
an opposing flow to the Fresh Gas in the exhalation block and thus create CPAP The
rear nozzle is used to generate the peak inspiratory pressure in the same way,
supplying constant pressures at all breathing rates.
The PIP regulator and gauge on the
front panel set the pressure that is
supplied to a solenoid valve which is
connected to the rear nozzle.
The Electronic Module controls the rate
and duration of the flow of Driving Gas
into the Exhalation block in opposition
to the Fresh Gas flow. This opposing
flow acts as a pneumatic piston and
creates a pressure wave at the ET
manifold. The lung inflation pressure
and hence the tidal volume are
controlled by the PIP regulator.
NOTE: The ventilator should be set to a square waveform for breathing rates
above 60 BPM
* The Valveless Ventilation Principle was designed and patented by Prof. J G Whitwam and Mr.
M. K. Chakrabarti of the R.P.G.M.S Hammersmith Hospital.
This patent is exclusively licensed to SLE
THE EQUIPMENT IS HOUSED IN TWO MODULES, PNEUMATIC AND
ELECTRONIC, THESE CAN BE UNCOUPLED FOR EASE OF SERVICE.