4 Use
In the event of absence of patient respiratory activity, this mode provides the guarantee of controlled
ventilation (PCV).
When the patient has regular and detectable respiratory activity, the unit responds by:
•
supplying a “spontaneous” cycle (PSV) if the time elapsed since the last “controlled” cycle is less
than the SIMV period,
•
supplying a “controlled” cycle (PCV) if the time elapsed since the last “controlled” cycle is greater
than the SIMV period.
If patient respiratory activity declines again after a “spontaneous” cycle, the unit waits for the SIMV pe-
riod - set TiMax to expire before triggering a “controlled” cycle (PCV) itself.
Insufflation in a spontaneous cycle with pressure support ends:
•
If the flow rate falls below the set expiratory threshold (E. Trig);
•
If the patient makes an expiratory effort,
•
or if the insufflation time reaches the maximum Ti setting (Timax).
Note:
Apnea ventilation can be activated; the apnea parameters should be suited to the con-
dition and requirements of the patient.
4.7.6 PSV NIV (Non Invasive ventilation)
[NIV = Non Invasive ventilation]
Principle
NIV is started by pressing the PSV NIV key.
PSV NIV mode enables the prescriber to ventilate a patient via a non-airtight interface: facial or nasal
mask, NIV headset.
Likewise, the ventilation setting ranges and the alarm thresholds and ranges are suited to NIV.
•
the PEEP setting is limited to 15 cmH2O,
•
the PS setting is limited to 25 cmH2O,
•
the E. Trig set-point is set at 50% by default,
•
the high and low VTi alarms are disabled;
•
the low MVe threshold is preset to 3 L/min (ADULT), 1.5 L/min (CHILD) and 1 L/min (INFANT).
Note:
NIV generally involves more or less variable leakage, which the unit estimates. Esti-
mates are then input into the inspiratory demand detection algorithm to limit self-triggering. It
may be necessary, however, to increase the level of this inspiratory trigger slightly if self-trig-
gering occurs too often.
In the volume-controlled modes used in NIV, the insufflated volume does not take leaks into account.
The user must also take special care to monitor the NIV volumes. Especially the difference between
the VT insufflated by the ventilator (VTi) and the VT measured at the expiratory valve outlet (VTe) must
be monitored. The difference indicates the level of leakage.
CAUTION:
Mask leaks are taken into account in the expiratory trigger mechanism.
Ventilation set-points
FiO2
inspired oxygen fraction
PS
pressure support ventilation (cmH2O)
37
Summary of Contents for MONNAL T75
Page 2: ......