Siemens Servo Ventilator 300, Service Manual

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Servo Ventilator 300/300A Description of functions
E382 E380E 061 01 03 01 Siemens-Elema AB 53
2
The change of pressure reference level from
one breath to the next breath within these 4
breaths is 75% of the change of pressure as
calculated by the above mentioned formula
(4) . Limitation: The increase of P
REF
from
one breath to the next breath is limited to
max 20 cm H
2
O.
For n > 3: The value of the parameter P
REF
[ref. formula (5) ] to be used during breath
number 5, and following breaths, will follow
the Normal procedure as described above.
The start up procedure is initiated at any one
of the following conditions (S) or (T):
(S): The Mode selector is changed to this
mode (PRVC or VS).
(T): If at least 15 sec have passed since last
Start up procedure started and if at least 5
breaths have passed since last Start up
procedure started and if then a single breath
ends with TV
M
< 50% x TV
P
. This condition
will normally occur at reconnection of a
patient after disconnection.
SIMV (Vol. Contr.) + Pressure Support mode
For the mandatory breaths; see Volume
Control mode above. For the spontanous
breaths; see Pressure Support mode below.
SIMV (Press. Contr.) + Pressure Support
mode
For the mandatory breaths; see Pressure
Control mode above. For the spontanous
breaths; see Pressure Support/CPAP mode
below.
Pressure Support/CPAP mode
Pressure Support mode:
This mode is active if the front panel setting
Pressure Support Level above PEEP:
> 2 cm H
2
O
In this case the
PRESSURE REGULATION PRESSURE
REF
signal will adopt the value:
P
REF
= PEEP + Pressure Support Level
above PEEP
using values according to corresponding
settings from the main block 1
FRONT PANEL
.
CPAP mode:
This mode is active if the front panel setting
Pressure Support Level above PEEP
- 2 cm H
2
O.
In this case the
PRESSURE REGULATION PRESSURE
REF
signal will adopt the value:
P
REF
= PEEP level + 2 cm H
2
O