Lowenstein Medical elisa 300, Instructions For Use Manual

Page: 315 / 457

Ventilation modes and parameters | A 5
Instructions for Use elisa 300-500 | Supplement A | SW 2.09.x | Rev. 11
99
A 5.4.1
Expiratory ramps
Via the expiratory pressure ramp setting, you adapt the rate at which the pres -
sure is reduced to PEEP level to the patient’s needs.
In pressure-controlled modes -> mandatory expiratory ramp
In pressure-support modes -> spontaneous expiratory ramp
Both ramps can be adjusted separately in steps, or they can be deactivated.
Expir
at
or
y flo
w
s
Pr
essur
e
Pinsp
PEEP
Steep pressure decrease
Expiratory flow curve in pul -
monary emphysema without
“splinting”
Expir
at
or
y flo
w
s
Pr
essur
e
Pinsp
PEEP
Gradual pressure decrease
Expiratory flow curve raised by phased
“splinting” of the airways
An unrestrained transition from inspiration to the PEEP level can cause local
collapse of airways in certain clinical conditions such as pulmonary emphysema.
By setting an expiratory pressure ramp, however, it is basically possible to protect
the small airways from collapse with a quickly acting pneumatic splint at the start
of expiration. The risk of collapse in the early expiratory phase is very high; an
expiratory ramp – similar to the effect of pursed lips breathing – is an effective
countermeasure to achieve a very favourable pressure course.
Remark
The option of setting a mandatory and a spontaneous expiratory
pressure ramp must be enabled on the configuration level.