for software version V1.021 or later. To find out the
software version installed, switch on OSIRIS 3. The
message «OSIRIS VX.XXX» will appear during startup.
The version number is X.XXX.
Pressure Support Ventilation (PSV)
PSV is a pressure-assisted spontaneous ventilation
mode.
A constant positive pressure is maintained in the pa-
tient circuit with each inspiratory effort by the patient.
The support flow is generated in order to maintain con-
stant inspiratory pressure.
When the pressure support setting is less than the
PEEP, a message appears on the screen. The pressure
support must then be increased.
The inspiratory phase ends when an expiratory ef-
fort from the patient is detected, or the TI setting is
reached.
TI
= I/E
set
FiO
in PSV mode depends on the ventilation param-
2
eters, resistance, and patient compliance. It remains
between 65 and 95%.
When switching from PSV mode to VCV/ACMV Air
+ O
or VCV/ACMV 100%, the VT setting can be
2
important. A message 'Adjust VT?' appears on screen
with an alarm. If the adjustment is not made within
seven seconds, insufflation is resumed with the
displayed VT value, which is based on the previous
setting.
As soon as the patient triggers a respiratory cycle,
the message "CYCLE SPONT" is briefly displayed.
When the respiratory cycle is initiated by the
machine, the message "CYCLE CONTROL" is briefly
displayed.
Setting the Minimum Respiratory Rate
This is a continuous adjustment, performed by rotat-
ing the graduated knob
The frequency can be adjusted from 6 to 40 bpm.
In case of patient inactivity, the device automatically
applies pressure-controlled ventilation according to
the set
parameters (F min, I/E, etc.).
As stated in the 'expiratory trigger' paragraph, the
Fmin setting affects the duration of the refractory
period of the expiratory trigger.
Adjusting the PEEP (Positive End-of-Expira-
tion Pressure)
This adjustment is performed by rotating the graduated
knob
.
The PEEP setting is adjusted continuously from 0 to
15 cmH
O.
2
Note: A mechanical safety device is placed on this
knob to prevent any accidental setting of PEEP > 10
cmH
O.
2
To set a higher PEEP value, press the metal index pin
located beside the knob.
x 1/F
set
set
.
YL033700 - Rev. 3a - 2019-02
Adjusting the pressure support
This adjustment is performed by rotating the inspirato-
ry flow rate knob
.
The pressure is adjustable from 3 to 44 cmH
The value appearing on the second line is the pressure
setting (PI max = pressure support + PEEP).
When the pressure support setting is less than the
PEEP, a message appears on the screen. The pressure
support must then be increased.
The inspiratory pressure adjustment does not
include the PEEP adjustment. For example: PI set = 25
cmH2O and PEEP = 10 cmH2O: At each insufflation,
the ventilator must supply inspiratory assistance of 15
cmH2O.
Adjusting the other ventilation parameters
(inspiratory trigger, I/E ratio, Pmin alarm,
Fmax alarm)
Press the MENU key to access each of the settings to
be adjusted in turn. The value appears on the first line
of the screen:
• Inspiratory trigger threshold (TRIG.);
• I/E ratio (I/E);
• Pmin alarm threshold (Pmin);
• High frequency alarm threshold (Fmax).
Next, adjust the parameter displayed to the desired val-
ue using the keys
or
Confirm by pressing the key. OSIRIS 3 will then take
the setting into account.
Repeat the operation for each parameter.
As stated in the 'Expiratory trigger' section, the
I/E ratio setting affects the duration of the refractory
period of the expiratory trigger.
Adjusting the Pmax safety setting
This is a continuous adjustment, performed by rotat-
ing the graduated knob
Pmax is adjustable from 10 to 80 cmH
The setting is displayed directly on the screen of the
device, represented by a vertical line.
Expiratory trigger
The expiratory demand is based on the detection of
pressure variations during the inspiratory phase.
At the beginning of insufflation, OSIRIS 3 has a refrac-
tory period, during which the expiratory trigger may not
be triggered.
The duration of this refractory period varies according
to the duration of the inspiratory time: it is equal to half
of the inspiratory time setting, with a minimum limit of
300 ms and a maximum limit of 1000 ms.
To limit any incompatibility between patient and ma-
chine, the minimum frequency setting should be
slightly less than that of the patient (approximately
20% less), which will give the best possible adjustment
of the refractory period.
Setting up the unit - EN
O.
2
.
.
O (hPa).
2
15