Testing The Oxygen Alarms; Testing The Breathing Circuit Alarms; Testing The Disconnection Alarm - ResMed Astral Series Clinical Manual

Testing the oxygen alarms

To perform these tests an oxygen sensor must be fitted. Tests are performed without supplementary
oxygen. Run a Learn Circuit prior to testing.
Alarm Event
Low FiO
2
High FiO
2

Testing the breathing circuit alarms

All breathing circuit alarm tests are conducted in (S)T mode using default settings and a single limb circuit
with intentional leak.
Alarm
Disconnection
High leak
NV mask/Rebreathing

Testing the disconnection alarm

Testing of the disconnection alarm should be conducted using a representative breathing circuit
configuration, oxygen flow into the circuit (if any), and the final ventilation settings.
The circuit used to test the alarm should include the patient interface (eg, tracheostomy tube /
endotracheal tube / mask / mouthpiece) to simulate the patient interface being accidentally detached
from the patient. This is a more challenging disconnection for a ventilator to detect than disconnections
elsewhere along the circuit.
For invasive interfaces, consider testing with a tracheal tube one size smaller than the patient's tube.
This checks that disconnection may still be detected even if the circuit resistance increases somewhat,
such as due to secretions within the cannula.
Alarm
Disconnection
Test procedure
Start ventilation. Set the alarm limit to 24%.
Start ventilation. Set the alarm limit to 19%.
Test procedure
Refer to Testing the disconnection alarms (see page 113).
Leave the circuit open and start ventilation.
Block the circuit (no mask attached) and start ventilation.
For Mouthpiece circuit only: Attach circuit to test lung via 22mm to 10mm
adapter for testing.
Test procedure
1. Ensure patient type and interface type have been correctly configured.
2. Start ventilation and wait a few cycles for ventilation to stabilise.
3. Disconnect the entire circuit (including patient interface, ie, mask, tracheal
tube, mouthpiece) then check that the alarm(s) configured to detect circuit
disconnection activate.
4. If the disconnection alarm does not sound, the alarm parameters may need
adjusting. Refer to Adjusting the disconnection alarm (see page 122).
Testing the alarms
English 113