Datex-Ohmeda Anesthesia Delivery Unit S/5, Technical Reference Manual

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Technical description A-EV1
Document No. 8502855
C-1
TECHNICAL DESCRIPTION A-EV1
General
The ADU Electronic Ventilator module (A-EV1) is an electronically controlled, time-cycled flow
generator. The ventilator delivers tidal volumes compensated for the actual inspiratory fresh gas flow
and real measured breathing circuit compliance.
The A-EV1 includes:
•
The control unit
The ventilator control unit consists of hardware, electronics and software to control mechanical
ventilation and to monitor patient pressure.
•
The bellows unit
The ventilator bellows unit drives the breathing gas to the patient. Bellows unit also connects
pressure sensing lines to the patient circuit.
•
The user interface
The control parameters are set with the main display and keyboard.
Main ventilation modes
The ADU has two main ventilation modes; Auto or Manual. The mode selection is done by turning the
Auto/Man. switch, located on the bellows block, to Auto or Man. position.
Auto position turns the ventilator on and simultaneously routes the gases in the bellows to the
patient. The ventilator may work in three Sub-modes.
In Man. position the user routes the gases to the patient manually, by means of a reservoir bag.
Auto mode
In Auto mode, the ventilator unit ventilates the patient.
Three different ventilation sub-modes may be chosen by the user:
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VCV = Volume Controlled (TV, MV)
•
SIMV = Synchronized Intermittent Mandatory Ventilation
•
PCV = Pressure Controlled Ventilation
See the User’s Reference Manual for detailed description of the modes.
The APL valve is not operating in Auto mode.
Manual mode
In Manual mode the operator ventilates the patient with a bag or the patient breathes spontaneously.
In Manual mode are the overflow valve and bellows not used.
The maximum circuit pressure is controlled by an Airway Pressure Limiting valve (APL). The valve is
located beside the Auto/Man. switch. When the pressure rises above the pre-set level, the APL valve
opens and gas bleeds to the scavenging system. When the patient breathes spontaneously, the
resistance of the APL valve is 1.5 cmH
2
O when the valve is set into minimum position.
Connections of the Electronic Ventilator module (A-EV1)
The connections of the module comprises pneumatic, mechanical and electrical connections.
•
The mechanical connection is between the frame and the module.