ResMed Elisee 350, Clinical Manual

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NOT013281-8
Triggering of (assisted) controlled cycles or spontaneous cycles with pressure support:
•
If there is no patient effort (patient-initiated breath) during the Wsync window, at the end of
the Wsync period the Elisée 350 delivers a controlled cycle (CC) based on the respiratory
rate F set on the ventilator.
•
If there is a patient-initiated breath during this window (see Scenario 1 in the previous
figure), the cycle will be assisted controlled (ACC), either pressure-controlled (in PSIMV
mode) or volume-controlled (in SIMV mode).
•
If there is no patient-initiated breath within the next Wsync window following an assisted
controlled cycle (ACC) (
Scenario 2 ), the Elisée 350 delivers a controlled cycle (CC). The
expiratory time (Te) of the assisted controlled cycle is increased by the ΔT time (limited to 5
seconds for adults and 1.5 seconds for children), corresponding to the anticipated time for
triggering the controlled cycle. The respiratory rate set on the ventilator therefore remains
constant.
•
If the patient initiates a breath during this window ( Scenario 3 ), a spontaneous breath with
pressure support is triggered.
Note:
If the patient initiates a breath during the Wsync window, the Wvs window is extended
by , which corresponds to the time remaining before another controlled cycle is triggered
(
Scenario 4
).
How SIMV mode works – Scenario 4:
Note:
•
During SIMV, use the High Pressure alarm to monitor the level of pressure in the patient’s
airways and prevent barotrauma.
•
In PSIMV mode, with both assisted controlled cycles and spontaneous cycles with
pressure support, the tidal volume depends on the set pressure gradient and on the
patient’s respiratory mechanics. It is therefore important that you monitor the expiratory
spirometry levels (expired tidal and minute volumes) to see the patient’s role in pressure
support.
Adjustable parameters (SIMV) Adjustable parameters (PSIMV)
F F
Flow shape Ti
V
T
Pi
Ti, max. flow or I:E Ti, max. flow or I:E
PEEP PEEP
Δ T
P
t (s)
ACC ACC CC
ΔT
Wvs: Trigger window for spontaneous pressure support cycles
Wsync: Trigger window for assisted controlled cycles (5 s or 1.5 s)
Tmech: Set mechanical period defined by the respiratory rate (F)
: Duration of the inspiratory phase
Δ T
Scenario 4: Patient effort during the Wsync
window increases the duration of the Wvs
window in the following cycle
(Controlled cycle if
there was no
patient effort)
t (s)