Datex-Ohmeda Aespire View, User'S Reference Manual

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3 Operation
M1132382
3-9
Measure circuit compliance
Exhaled tidal volume (TVexp) measures the gas needed to fill the
patient circuit at the measured pressure. The compliance factor can
be used to calculate the approximate gas which goes into expanding
the compliant patient tubing and not delivered into the patient.
1. Set the ventilator to volume control ventilation (VCV) mode.
2. Set the ventilator parameters.
• TV = 25 ml.
• RR = 20.
• I:E = 1:1.
• Pmax = 100 cmH2O.
• PEEP = Off.
3. Occlude the patient Y.
4. Turn on mechanical ventilation.
5. Monitor the exhaled tidal volume (TVexp) and the measured peak
airway pressure (Ppeak).
6. Calculate the tubing compliance factor.
• TVexp/(Ppeak - 2.5* cmH2O) = Compliance factor in
ml/cmH2O.
• Example:
— Ppeak = 30 cmH2O.
— TVexp = 25 ml.
— 25/(30 - 2.5) = 0.9 ml/cmH2O.
*Pressure created by the force of the bellows.
Pressure waveform
The pressure waveform shows the measured value of the airway
pressure. The waveform automatically adjusts the time and pressure
scales. The time scale changes with the respiratory rate. The
pressure scale changes with the pressure limit.
Note See the “Specifications and Theory of Operation” section for more
waveform information on the ventilation modes.
Respiratory Rate (breaths per minute) Time scale (seconds)
0 to 25 0 to 16
26 to 75 0 to 8
76 to 100 0 to 4