Siemens Drager medical Carina, Instructions For Use Manual, Page: 130 / 144

Description
130
Instructions for Use Carina SW 3.n
In the course of progressively weaning the patient
from artificial ventilation, the ventilation frequency f
is further reduced while the spontaneous breathing
time is increased, so that the required total minute
volume is supplied more and more by spontaneous
breathing.
The ventilation frequency can be reduced to 5/min.
AutoFlow
On Carina, the AutoFlow function is always incor-
porated in VC-SIMV ventilation mode.
With AutoFlow, the inspiration flow is automatically
adjusted to changes in lung conditions (C, R) and
to the spontaneous breathing demand of the
patient.
Always set the alarm limits »Paw high« and
pressure limitation »P
max
« in order to limit any
rise in airway pressure or tidal volume VT if
compliance has changed.
The selected inspiration time Ti is typically much
longer than the fill time of the lung. The inspiration
pressure PIP corresponds to the minimum value
resulting from both tidal volume VT and
compliance C of the lungs.
Carina automatically controls the inspiration flow so
that there is no pressure peak due to the resist-
ances of the tube and airways. As is usually the
case with constant-volume ventilation strokes,
inspiration pressure PIP alters according to
changes in compliance C. With AutoFlow these
changes occur in maximum increments of 1 mbar
from ventilation stroke to ventilation stroke. Inspira-
tion pressure PIP is set by the pressure limitation
P
max
.
If tidal volume VT is reached (inspiration flow = 0)
before inspiration time Ti has elapsed, the patient
can breathe in and out at the level of inspiration
pressure PIP during the remaining inspiration time.
044
Paw
Ramp
PEEP
Paw
PIP Ramp
Ramp
T
i
T
e
f
low
t
t
Flow
high
Ramp
Pmax
V
T
1
Without spontane-
ous breathing With spontaneous
breathing