Dräger Babylog 8000 plus Instructions For Use Manual page 162

Principles of operation
In case of major tube leakage (cf. description of
leakage rate), the exhaled tidal volume can (as in
other ventilation modes as well) be greater than
the tidal volume measured on the expiratory side.
Then the inspiratory and expiratory tidal volumes
are different. If, in the course of a mechanical
breath, the current inspiratory tidal volume
exceeds the expiratory tidal volume (A) of the
previous breath by an amount dependent on the
actual leakage rate, the device terminates the
inspiration.
If the flow sensor fails or if the patient no longer
breathes spontaneously, mandatory ventilation
begins as in the IPPV/IMV ventilation mode.
Separate expiratory flow
The additional setting VIVE can be used to set the
continuous expiratory flow
the continuous inspiratory flow
inspiratory flow has an effect on mechanical
breaths. Expiratory flow has an effect on
spontaneous breathing phases and in the CPAP
ventilation mode.
Effects of increased expiratory flow:
– Greater flow is made available to the patient for
spontaneous breathing than is provided for the
mechanical breaths.
– Increased turbulence in the breathing circuit
benefits the flushing of the dead space in the Y-
piece.
– In the CPAP ventilation mode, the pattern of
manually triggered mechanical breaths can be
set separately.
A reduced expiratory flow can be used to save
oxygen.
162
independent of
exp
. The
insp
High-frequency ventilation (HFV)
Ventilation with high-frequency pressure
oscillations enables gas to be exchanged in the
lungs despite very small tidal volumes (often in the
dead space volume range). While pressure
amplitudes may be considerable in the breathing
circuit, only small fluctuations occur around the
mean pressure in the lungs.The mechanical load
due to periodic expansion and relaxation of the
lungs is low.
Functional principle:
Like the respiratory cycles in conventional
mandatory ventilation, high-frequency oscillations
are controlled via the diaphragm in the expiratory
valve. In the inspiratory phases of the oscillations
the pressure is greater than the mean airway
pressure; in the expiratory phases it is less than
the airway pressure. The mean pressure is
automatically regulated to correspond to the set
value PEEP/CPAP.
In order to regulate the pressure, the device must
automatically set the flow and I:E ratio of the
cycles. The setting knob for flow (
has no effect during high-frequency oscillation.
The additional setting VIVE is likewise unavailable.
The pressure amplitudes at the Y-piece depend on
the set value for amplitude, as well as on the
breathing circuit and on the patient's respiratory
system. For this reason, set the amplitude on a
relative scale from 0 % to 100 % until the desired
pressure is reached or the desired tidal volumes
are set.
Instructions for use Babylog 8000 plus SW 5.n
Insp. Flow
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