Maquet SERVO-air, Руководство пользователя

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5.4 Volume Control (VC)
Volume Control (VC):
• delivers a preset tidal or minute volume over
a preset inspiratory time and at a preset
respiratory rate, regardless of changes in
lung or thorax resistance or compliance
• maintains a constant flow with varying peak
pressure
The ventilator system can be configured so
that either tidal volume or minute volume is
set.
1 2 3 4
5 6 7 8
The following parameters are set:
1. Oxygen concentration (%)
2. PEEP (cmH
2
O)
3. Respiratory rate (b/min)
4. Tidal volume (ml) or minute volume (l/min)
5. I:E ratio or Inspiration time (s)
6. Pause time (% or s)
7. Inspiratory rise time (% or s)
8. Trigger
Refer to section Settings on page 43.
The airway pressure is dependent on the tidal
volume, the inspiration time and the resistance
and compliance of the respiratory system. The
set tidal volume will always be delivered. An
increase in resistance and decrease in
compliance will lead to an increased airway
pressure. The delivered pressure can vary, so
in order to protect the patient's lungs from
excessive pressure, it is very important to set
the upper pressure limit to a suitable value.
Patients may trigger extra breaths if they can
overcome the set trigger level.
Flow adaptation
Patient inspiratory efforts can also result in a
higher inspiratory flow and tidal volume than
were preset. This is because the ventilator
system enables the patient to modify both flow
rate and timing.
Thus, if the patient demands a higher flow than
the calculated constant flow, the system will
sense any sudden pressure drop of > 3 cmH
2
O
and temporarily enables PS to deliver a higher
flow adapted to patient demand.
SERVO-air Ventilator System v2.2, User's Manual
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| Ventilation modes | 5 |