Stephan EVETR, Instructions For Use Manual, Page: 160 / 254

7 Ventilation modes
160 GA-070T-0518V2.7-HAO-EN

Fritz Stephan GmbH
The trigger is only active within a so-called trigger expectation window.
The length of this expectation window and the time gap between the
windows vary depending on the set expiration time. The expiration time
is divided into two phases.
In the first phase (Texp
spon
= 50% of Texp), the patient can only breathe
spontaneously. Even when the trigger threshold is crossed, there is no
mandatory support from the ventilator. If the patient breathes sponta-
neously during the second phase of the expiration time, the
EVE
TR
now
delivers a mandatory breath.
The expiration time is divided into two phases. In the first phase (Texp
spon
= 50% of Texp), the patient can only breathe spontaneously. Even when
the trigger threshold is crossed, there is no mandatory support from the
ventilator. If the patient breathes spontaneously during the second phase
of the expiration time, the
EVE
TR
now delivers a mandatory breath. The
change from the upper to the lower level is either upon expiration of the
set inspiration time or is patient triggered at incipient expiration by the
patient. After the first inspiration phase has passed (Tinsp
spon
= 50% of
Tinsp). As a result, the patient controls the beginning, progress, and
volume of the mechanically supported breath.
This differentiates DUOPAP from other mixed ventilation modes where
spontaneous and controlled breaths follow one after another. In addition,
mechanical ventilation and spontaneous breathing can be combined
simultaneously.
Fig. 88: DUOPAP