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Publication 5404-001-REV-C
Operating Modes
The Inspira ASV
v
has two operating modes, Volume Mode and Assist Mode. To toggle
between the modes press the [Select Mode] key. The upper right hand corner of the
display will show which mode the ventilator is currently in, either VOL or ASST.
The Inspira ASVp has four operating modes – VOLUME, VOLUME ASSIST, PRESSURE,
and PRESSURE ASSIST. To toggle between the modes, stop the machine by pressing the
RUN/STOP key (if it is presently running) and then press the SELECT MODE key.
When the mode is switched from VOLUME ASSIST to PRESSURE or PRESSURE ASSIST
to VOLUME, the machine will re-initialize to place it in its "home" position for that
mode. The upper right hand corner of the display will show which mode the ventila-
tor is currently in - VOL,VOLASST, PRES, or PRSASST.
Volume Mode
When in Volume Mode the ventilator delivers a known volume of gas to the animal
over a specified amount of time for each respiration stroke. This is the basic operating
mode for volume-controlled ventilation.
Pressure Mode (Inspira ASVp Only)
When in Pressure Mode, the ventilator delivers gas until the desired airway pressure is
reached or the end of the inspiration cycle has occurred. If the airway pressure is not
reached within the inspiration time, the machine will automatically adjust the inspira-
tory flow rate by incrementally increasing the tidal volume until the pressure limit is
achieved. If the pressure limit is reached early in the inspiratory cycle, the machine
will automatically decrease the flow rate so that the limit is reached toward the end of
the cycle. If the limit is reached very early in the cycle, the machine will also report an
Occlusion Fault.
Volume Assist Mode
Pressure Assist Mode (Inspira ASVp only)
Assist mode is a more advanced mode used to help wean animals off of mechanical
respiration. This mode detects when the animal is trying to breathe on its own via a
drop in the airway pressure. This mode allows the animal to initiate the respiration
strokes. The ventilator starts a respiration stroke when the airway pressure falls below
a user-defined threshold. If five respiration strokes occur without the airway pressure
dropping below the assist pressure threshold, the animal may not be trying to initiate
a breath. The ventilator will continue to operate in the current assist mode but the
assist alarm will sound to request user intervention. The user may adjust the respira-
tion parameters and/or the assist pressure to obtain correct performance.
Key
CAUTION: Assist Mode should only be used when trying to wean
animals from mechanical ventilation.
Operation: Respiration Profiles
