WM 68071 05/2021
MEDUMAT Standard
2
EN 157
7 Description of the modes
The SIMV + ASB mode is used for volume-controlled ventilation
with a fixed mandatory minute volume. The patient can breathe
spontaneously between the mandatory mechanical breaths and
thereby increase the minute volume. During spontaneous
breathing, the mandatory mechanical breath is synchronized with
the patient's breathing. The mandatory minute volume and the
mandatory respiratory rate remain unchanged. When the
maximum ventilation pressure (pMax) is achieved, the device
maintains the pMax up until the end of the inspiration time and
then switches to expiration. As such, the set tidal volume is possibly
not fully applied if the maximum ventilation pressure (pMax) is
achieved during inspiration. The patient can trigger a mandatory,
pressure-controlled mechanical breath during a predetermined
trigger window. The trigger window is available in the final 20 %
of expiratory time Te. For the rest of the time, the patient can
breathe spontaneously or with the aid of pressure support
(see "7.3.4 CPAP + ASB mode", page 148).
Pressure
Time
SIMV + ASB
p
Max
1/Freq. (set)
Mechanical ventilation Synchronized mechanical
ventilation
1/Freq. (current)
Trigger time slot
ΔT
Spontaneous
respiration
Assisted
spontaneous
breathing
pPlat
ΔpASB
PEEP