CareFusion AVEA - Appendix I: Volumetric CO2 Calculations; Volumetric CO2 Calculations

AVEA ventilator systems Appendix E: Sensor Specifications & Circuit Resistance 219
L2786 Rev. M
Circuit Resistance Test
The resistance of a neonatal patient circuit should be tested for proper functionality of the ventilator for neonatal patient
size applications. Excessive circuit resistance under these circumstances may result in triggering a Circuit Occlusion
Alarm.
This resistance test applies to all neonatal applications except nCPAP.
1. To measure the resistance of the breathing circuit, set-up the system as follows:
Mode
TCPL AC
Flow Correction
ATPD (Set in utility screen, configuration tab)
Rate 4
Inspiratory Pressure 10 cmH
2
O
Peak Flow
15 L/min
Inspiratory Time
3.0 sec
PEEP
0 cmH
2
O
Flow Trigger
20 L/min
Pressure trigger
20 cmH
2
O
% O
2
21 % (no Heliox)
Bias Flow
2 L/min
Humidifier
Dry chamber inline, humidifier power off
Patient circuit
Clean and dry
Expiratory Filter
Installed, clean and dry
Test Lung Not used, block the wye
2. Select waveforms Pinsp and Paw.
3. With the patient wye blocked, allow a TCPL breath to occur, and then press the FREEZE key and scroll the Cursor Line
with the data dial until it is positioned in the middle of the inspiration portion of the breath.
4. Read the pressure from the Pinsp and Paw waveforms from the Cursor Line data.
5. Subtract Paw from Pinsp. Pinsp – Paw = X cmH
2
O
6. The resulting pressure difference (X cmH2O) must not exceed 3.1cmH
2
O at a flow of 15 L/min, and there must not have
been an occlusion alarm active for that breath.
7. Reset the “Flow Correction” setting in the Utility screen to “BTPS” (normal setting for patient use).
Note:
We do not recommend using a neonatal circuit in a pediatric patient size application.