PHILIPS Respironics Trilogy 100 Clinical Manual page 78

The Passive circuit provides leak compensation while the Active PAP
circuit does not. When using the Passive circuit in Volume Ventilation,
the set Vti is delivered to the patient above the calculated circuit
and cuff (or mask) leak. This is different from traditional active circuit
ventilation where the cuff (or mask) leak reduces the tidal volume
delivered to the patient. Volume ventilation with the Passive circuit
delivers an inspiratory tidal volume close to the device setting
regardless of leak; this should be considered when transitioning a
patient from an active to a passive circuit. With a Passive circuit, Vte is
estimated based on the calculated sum of circuit and cuff (or mask)
leak.
Circuit Disconnect
This setting enables or disables the circuit disconnect alarm. If
enabled, an audible alarm will sound when a large, continuous air
leak (such as mask removal) has been detected in the circuit.
You can choose Off to disable the alarm. Or, you can increase or
decrease the setting from 5 to 60 seconds in 5 second increments.
For example, a setting of 10 means that the alarm will sound after the
circuit has been disconnected for 10 seconds.
WARNING
You should not rely on any
single alarm to detect a circuit
disconnect condition. The Low
Tidal Volume, Low Minute
Ventilation, Low Respiratory
Rate, and Apnea alarms should
be used in conjunction with the
Circuit Disconnect alarm.
Chapter 5 Viewing and Changing Settings
71