Gradian Universal Anaesthesia Machine, Руководство по обслуживанию

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The low-resistance draw-over vaporizer adds volatile agent to the carrier gas passing through it. Volatile agent is added by
using the selector wheel to achieve the desired percentage. The resulting anesthetic supply gas is comprised of oxygen,
volatile agent and a variable amount of room air. The anesthetic supply gas flows from the back bar at low pressure to the
breathing block and the bellows.
An oxygen analyzer measures the oxygen concentration of the supply gas passing to the patient. The reading is displayed
on the analyzer screen.
As the supply gas flows past the sampling point for the consumable oxygen sensor, it passes the first one-way valve, then
enters the bellows chamber. Depending on the configuration, the second one-way valve is immediately after the bellows in
the breathing block, or on the inspiratory Y-piece connection.
During spontaneous breathing both non-return valves open for inspiration and close during expiration. The bellows will not
fill with exhaled gas.
The bellows is used for intermittent positive pressure ventilation, also known as IPPV or controlled ventilation. When the
bellows is raised, supply gas flows through the first non-return valve into the bellows. The second non-return valve remains
closed.
As the bellows are pushed down, the supply gas flows out through the second non-return valve into the inspiratory limb. The
first non-return valve is closed.
Another pressure relief valve ensures that excessive manual force on the bellows cannot cause harm to the patient.
The UAM uses a conventional Y-piece patient connection. Exhaled gas returns to the UAM via the expiratory limb of the
Y-piece and then passes by a third one-way valve and the Fenton balloon to the scavenger port. The balloon acts as an
inflating valve which enables controlled ventilation of the lungs, the third valve prevents back-flow during spontaneous
breathing.
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