Dräger Oxylog 3000, Instructions For Use Manual, Page: 127 / 138

Instructions for Use Oxylog 3000 SW 1.n
127
Principles of Operation
The trigger window is 5 seconds long. If the
expiration times are less than 5 seconds, the
trigger window covers the entire expiration time
minus a minimum expiration time of 500 ms.
Since the synchronization of the mandatory
ventilation stroke reduces the effective SIMV time,
which would result in an undesirable increase in
effective respiratory rate, Oxylog 3000 prolongs the
subsequent spontaneous breathing time by the
missing time difference
Δ
T – thus preventing an
increase in SIMV frequency. The frequency
parameter Freq. remains constant. This parameter,
in combination with the tidal volume VT, sets the
minimum ventilation.
During the spontaneous breathing phases, the
patient can be assisted with pressure by ASB
pressure support.
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 increasingly supplied by spontaneous
breathing.
ASB(PS)
A ssisted S pontaneous B reathing ( P ressure
S upport
)
Pressure support for insufficient spontaneous
breathing.
The device takes over part of the inhalation
function, with the patient maintaining control of
spontaneous breathing.
The CPAP system supplies the spontaneously
breathing patient with breathing gas, even if the
inspiration effort is weak.
The pressure support of the ASB system is started:
when the spontaneous inspiration flow reaches the
set value of the flow trigger, or at the latest
when the spontaneous inspired volume exceeds
25 mL.
043
Phase
I II
Paw
Insp.
Flow
t
t
CPAP
Start of inspiration
max. 4 s
End of inspiration
25 % Insp. Flow
P
ASB
over PEEP