Maquet SERVO-air, Руководство пользователя

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5.5.1 Bi-Vent/APRV in detail
1
2
3
4
5
The circles in the figure indicate patient triggering.
1. Bi-Vent/APRV cycle = T
high
+ T
PEEP
2. PEEP
3. P
high
4. PS above PEEP
5. PS above P
high
Bi-Vent/APRV allows for spontaneous
breathing/PS ventilation at two different
pressure levels. These basic levels are
individually set, as well as the time in seconds
at each level. The ventilator system always
tries to synchronize with the patient's
breathing. The main difference between
Bi-Vent and APRV is the inverse I:E ratio in
APRV.
Since Bi-Vent/APRV is basically a controlled
mode of ventilation, apnea alarm and backup
ventilation are not available. It is also very
important to set the lower and upper alarm
limit for expired minute volume.
Each Bi-Vent/APRV cycle is regarded as
autonomous and therefore most of the
measured values are updated every cycle, i.e.
minute volume, respiratory rate, mean
pressure and end expiratory pressure.
Associated alarms are also handled for every
cycle.
At extreme settings, the update of measured
values and alarms will show a mandatory
frequency dependence even in the face of
preserved spontaneous breathing.
As a result of switching between two different
pressure levels, the tidal volumes may vary
significantly between different breaths. This
may also be the case for etCO
2
(end tidal CO
2
)
concentration.
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SERVO-air Ventilator System v2.2, User's Manual
| 5 | Ventilation modes |