Selecting The Proper Flow Setting - Inogen ONE G4 Technical Manual

For further information regarding the use of the Inogen One G4, please consult the User
Manual.

2.4. Selecting the Proper Flow Setting

2.4.1. Bolus Volumes Specification
All oxygen conserving devices (OCD's) function differently, and therefore it is prudent to
titrate patients for any new conserving device. Delivery timing, bolus volume, and oxygen
concentration all contribute to a patient's fraction of inspired oxygen (FiO
to the OCD's efficacy at maintaining the patient's blood oxygen saturation.
As an oxygen concentrator, the Inogen One G4 does not contain a finite stored volume of
oxygen, such as with compressed gas or liquid cryogenic systems. The Inogen One G4
can provide oxygen to the patient as long as a source of electricity is available. Because
the oxygen is being produced as it is used, supply of oxygen is rate-limited. The Inogen
One G4 delivers up to 630 ml/min of 90% (+6%/-3%) oxygen.
At each flow setting, the Inogen One generates a specific amount of oxygen (210ml per
setting), and the on-board OCD attempts to deliver all of this product to the patient. This
is equivalent to a conserving ratio of 4.76 at all flow settings and breathing rates. Slower
breathing patients will receive larger boluses, and faster breathing patients will receive
smaller boluses.
DESIGN
NOTE
The following table summarizes the nominal bolus volumes (+/- 3ml or 10%) delivered by
the Inogen One G4 at 20C and sea level:
Bolus Volume is tuned to provide the correct bolus volume when delivered
DESIGN
NOTE
2.4.2. Trigger sensitivity
The conserver will trigger when the negative pressure at the internal sensor reaches -
0.12 cm H 0 (+/- 20%). This low trigger sensitivity allows for breath detection of very
2
CONFIDENTIAL and
96-06917-00-01 rev C
PROPRIETARY
This method of bolus volume determination is similar to what is
experienced by a patient using a continuous flow concentrator – actual
alveolar oxygen inspiration is more closely linked to flow setting than to
Flow Flow Rate
setting (ml/min)
1.0 210
2.0 420
3.0 630
through a nasal cannula such as the Salter Labs 1600SOFT. If bolus
volumes are measured without a cannula or with a different type of nasal
cannula, bolus volumes will vary from values stated in the table above.
DCR 20-328
breathing rate.
10 BPM 20 BPM
(ml/bolus) (ml/bolus)
21.0 10.5
42.0 21.0
63.0 31.5
INOGEN ONE G4 TECHNICAL MANUAL
), and therefore
2
25 BPM
(ml/bolus)
8.4
16.8
25.2
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