GE Datex-Ohmeda Aisys Carestation Reference Manual page 82

Aisys
Mechanical expiration
D
6
6
AP Airway Pressure
D Drive gas
FG Fresh Gas
SGR Sample Gas Return
4
Expiratory flow
5
Flow to bellows
6 To scavenging
Figure 2-37 • Mechanical expiration
2-50
Drive-gas flow stops and the exhalation valve opens. Exhaled gas flows from the
patient (4), through a unidirectional valve (expiratory check valve) and into the bellows
(5). Residual drive gas (D) flows out of the bellows to the scavenging system (6).
If PEEP is selected, static pressure on the pilot port of the exhalation valve sets the
PEEP level.
During exhalation, fresh gas flows backwards through the absorber (FG) into the
expiratory limb, downstream of the expiratory check valve.
For machines that are plumbed to return sample gas to the breathing system, the
returned gas (SGR) enters the breathing system after the expiratory check valve.
5
5
AP
FG
SGR
FG
4
04/08 M1046983