CAE Athena - Paco2 Set-Point; Pao2 Set-Point; I to E Ratio (1:X)

Müse Parameter Descriptions
209
PN: 905K520652 v2.8
PaCO
2
Set-point
The PaCO
2
Set-point parameter is a set-point for PaCO
2
. The control-of-breathing model adjusts
tidal volume and respiratory rate in order to bring the PaCO
2
toward this set-point. Factors that
influence the success of this control effort include baseline tidal volume, baseline respiratory rate,
respiratory gain, O
2
consumption, respiratory quotient, lung compliances, chest wall compliance,
bronchial resistances, the presence of artificial airways in the simulator and the inspired gas mixture.
When the PaCO
2
Set-point is set to a new value, the physiological controls adjust the simulator’s
respiratory pattern in an attempt to attain the desired set-point. For example, when the set-point is
raised from 40 to 50 mmHg, there is a transitory decrease in respiratory rate and tidal volume, as the
physiological controls attempt to drive the PaCO
2
toward 50 mmHg. When the PaCO
2
reaches the
new set-point, the simulator’s respiratory rate and tidal volume should return to normal values.
Default: 40 mmHg
Range: 20.0 mmHg - 70.0 mmHg
PaO
2
Set-point
The PaO
2
Set-point parameter is a set-point for PaO
2
. When PaO
2
is below the set-point value,
progressive stimulation of spontaneous minute ventilation occurs. Both tidal volume and respiratory
rate rise, which under appropriate conditions results in PaO
2
moving closer to the set-point. Factors
that influence this control effort include baseline tidal volume, baseline respiratory rate, respiratory
gain, O
2
consumption, respiratory quotient, lung compliances, chest wall compliance, bronchial
resistances, the presence of artificial airways in the simulator and the inspired gas mixture. Minute
ventilation is not affected for PaO
2
above the set-point.
For example, if PaO
2
Set-point is set to 100 mmHg and PaO
2
drops to 90 mmHg, ventilatory
stimulation occurs. When the PaO
2
reaches the new set-point, the simulator’s respiratory rate and
tidal volume are again controlled to maintain PaCO
2
at the PaCO
2
set-point. Also, see PaCO
2
Set-
point.
Default: 100.00 mmHg
Range: 20.0 mmHg - 100.0 mmHg
I to E Ratio (1:X)
The I to E Ratio (1:X) parameter sets the inspiratory-expiratory (I:E) ratio for spontaneous ventilation.
At the default setting, the time for exhalation is twice that of inhalation.
Default: 2
Range: 0.5 - 7.0