Covidien Puritan Bennett 700 Series, Руководство по обслуживанию

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Theory of operation
2-26 10070389 Rev. A Puritan Bennett™ 700 Series Ventilator System Service Manual
Figure 2-14. Patient system pneumatic diagram
• The inspiratory (main flow) filter (the Puritan Bennett™ D/Flex or Re/Flex Filter) helps
protect the patient from contamination by the gas supplies, and helps protect the
ventilator from contamination by the patient system. The filter captures particles of
0.3
μ
m nominal and larger at a flow of 100 L/min with 99.97% efficiency. It has 22-mm
ISO conical connections.
• The ventilator breathing circuit provides a conduit for gas flowing between the ventilator
and patient. It is composed of two smooth-bore “flex” tubes, the inspiration and
exhalation tubes. The inspiration tube carries gas from the ventilator to the patient, while
the exhalation tube carries exhaled gas from the patient to the ventilator.
• The humidification device moistens the gas delivered to the patient so it more closely
approximates gas inspired through the nasal passages.
• The collector vial collects moisture in the exhaled gas to help keep water out of the
exhalation system, in particular the expiratory filter.
• The expiratory filter helps prevent bacteria in the patient’s exhaled gas from being
vented to room air and reduces cross-contamination of the ventilator. The filter captures
particles of 0.3
μ
m nominal and larger at a flow of 100 L/min with 99.97% efficiency. It has
22-mm ISO conical connections.
Exhaled gas flows in through the filter’s center, then through the hydrophobic paper
toward the filter’s sides, and out the filter outlet. Liquid water drains into the collector
vial.
7-00092
Expiratory
filter
Inspiratory
filter
From
inspiration
manifold
To exhalation
check valve
Collector
vial
To patient