Covidien Newport e360, Руководство по обслуживанию

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Theory of Operations
A-10 Service Manual
baseline pressure after a positive pressure breath, and decreased potential for auto-PEEP. A filter is
used between the expiratory limb of the breathing circuit and the expiratory (From Patient) port to
prevent contaminants in the exhaled gas from entering the exhalation system.
A.5.1
Protection From Overpressurization
In the case of a High Pressure alarm violation, Sustained High Baseline Pressure alarm violation with
suspension of ventilation, Device Alert shutdown, Both Air/O
2
Supply Loss alarm shutdown or
power off, the exhalation valve opens to allow the patient to exhale. The exhalation valve also opens
any time breathing circuit pressure reaches 135 cmH
2
O.
With exception of the High Pressure alarm, these same conditions cause the inspiratory emergency
relief valve solenoid to be de-energized, which allows the circuit pressure to vent if it is above the
relief valve cracking pressure of 4 cmH
2
O. The relief valve also opens any time breathing circuit
pressure reaches 140 cmH
2
O.
A bacteria filter is placed between the inspiratory limb and the inspiratory (To Patient) port to
prevent contaminants in the exhaled gas from entering the inspiratory manifold when the
inspiratory emergency relief valve is de-energized.
A.5.2
Protection From Rebreathing Exhaled Gases
In the case of a Sustained High Baseline Pressure alarm violation, Device Alert shutdown, Both Air/O
2
Supply Loss alarm violation or power off, gas delivery to the patient will cease. The inspiratory manifold
and exhalation valve systems are designed to protect the patient from rebreathing exhaled gas under
this condition. A mechanical emergency intake valve in the inspiratory manifold allows the patient to
breathe room air into the breathing circuit. The exhalation valve acts as a one-way valve allowing the
patient to exhale but not inhale. This system provides fresh gas through the inspiratory limb and an
easy route for exhalation through the exhalation valve in the case of ventilator shutdown. If the
exhalation valve is blocked when the ventilator shuts down, the patient will exhale through the
inspiratory emergency relief valve when pressure in the circuit reaches the cracking pressure of 4
cmH
2
O.
A.6
Description of Functional Subsystems
The ventilator includes the following subsystems:
•
Inhalation system
•
Exhalation system
•
Electronics