ResMed Elisee 350 Clinical Manual page 32

Expiratory phase
The device cycles into the expiratory phase:
1. When the expiratory trigger setting is reached. The setting may be:
•
•
2. If the target pressure of 2 cm H
pressure may be due to a patient-initiated active exhalation) (Scenario 3).
3. If, on reaching the maximum inspiratory time set by the user, none of the above conditions
have been met (Scenario 4) (for example, if there is a leak in the circuit and the flow does not
decrease fast enough in relation to the times set for the expiratory trigger).
P
PEEP
V
Note: The set PS level is added to the PEEP level.
The adjustable parameters are as follows:
Adjustable parameters (PS)
PS
PEEP
Rise time
Inspiratory pressure and flow triggers
Expiratory trigger
Apnea parameters. Depending on the type of mode selected:
•
Volume-controlled mode: Tapnea, V
•
Pressure-controlled mode: Tapnea, Pi, F and Ti.
Ti Max
Leak
FiO
2
WARNING
Unlike with the controlled cycles in CV and ACV modes, in Pressure Support mode, tidal
volume is not fixed but depends on the patient's inspiratory effort and resistance and
compliance characteristics. Tidal volume and minute volume must be monitored by setting
volume alarms.
Pressure support with minimum tidal volume (PS.V
This is a mixed mode which combines pressure support and volume-controlled ventilation to
provide a high level of patient safety. In this mode, the ventilator delivers a minimum tidal volume
in every cycle. This is necessary, for example, when the patient's inspiratory effort decreases, or
the patient's compliance changes. PS.V
invasive ventilation, or during weaning trials for patients treated for respiratory failure.
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Based on the percentage of the maximum flow (Scenario 1, see figure)
Based on the intersection of the flow curve with the 2.3 s line (Scenario 2).
PS
Scenario 1: Percentage of the
maximum flow
Scenario 2: Intersection of flow
curve with 2.3 s line
, F and Ti (or
T
O is exceeded during the decreasing flow stage. The excess
2
Scenario 3: Pressure "overshoot" (> 2 cm H
2.3 s
°
max or I:E)
mode is particularly appropriate for patients receiving
T
O)
2
Scenario 4: Set Ti Max value reached
)
T
NOT013281-8
t
t