ResMed Astral Series Clinical Manual page 53

Circuit options
The following icons are used to report the Learn Circuit results:
Learn Circuit Results
Icon Description
Learn Circuit completed
Learn Circuit not tested. Default circuit characteristics will be applied. Accuracy of control and monitoring may not be
met. Ensure that ventilation and alarms are effective before proceeding further.
Learn Circuit completed. Circuit resistance is high.* The device will use the learned circuit characteristics. Accuracy of
control and monitoring may not be met. Ensure that ventilation and alarms are effective before proceeding further.
*The International Standards Organisation (ISO) has judged that patients ventilated with tidal volumes in excess of
300 mL (Adult range) should use breathing circuits with a resistance no more than 6 cmH
rate of 30 L/min and 6 cmH
This circuit configuration may be appropriate for particular patients and hence clinical discretion is
required. Should ventilation cease for any reason, the patient must overcome this resistance in order to breath.
Note: Patient/carer should be informed that this icon will appear each time Learn Circuit is performed using this
configuration.
Learn Circuit has failed. Default circuit characteristics will be applied.
Below are general steps to resolve the Learn Circuit issue. Refer to Learn Circuit Troubleshooting (see page 160) for
suggested actions on the error code.
1. Inspect the circuit and proximal lines for disconnection or excessive leak.
2. Check that the circuit is correctly connected and matches the selected circuit type.
3. Check that the correct circuit adapter is installed for the selected circuit type.
4. Check the module, the blue membrane and sensor are pressed all the way in and sit flush with the enclosure.
Accuracy of control and monitoring will be degraded. Ensure that ventilation and alarms are effective before
proceeding further.
Device Test Results
Icon Description
Device Test has passed.
Device Test has not been run. This only occurs on setting up a new therapy program.
Device Test has failed. Learn Circuit cannot be run.
Below are general steps to resolve the Learn Circuit issue. Refer to Learn Circuit Troubleshooting (see page 160) for
suggested actions on the error code.
1. Inspect the air inlet for foreign materials.
2. Inspect the air filter and replace it, if necessary. Refer to Cleaning and maintenance (see page 132) for further
instructions.
3. Remove the expiratory module and inspect the module and blue membrane for any foreign materials.
4. Re-install the module, ensuring that it is securely in place.
5. Repeat Learn Circuit. If problem persists, refer to Learn Circuit Troubleshooting (see page 160) for suggested
actions on the error code.
If you choose to proceed with ventilation, accuracy of control and monitoring will be degraded. Ensure that ventilation
and alarms are effective before proceeding further.
46
O at 15 L/min for tidal volumes less than 300 mL (Paediatric range).
2
O pressure drop at a flow
2