Page 52 - Journal of Special Operations Medicine - Fall 2016

Turbine technology, however, allows the Elisée 350 ven- Finally, the tested system is able to provide high Fio
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tilator to operate without any external compressed gas levels without oxygen-cylinder consumption. However,
source. This is important because the oxygen supply in it seems essential to monitor delivered Fio when ven-
10
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remote and low-resources contexts can be unobtainable tilators are used with low-pressure sources of oxygen
or cumbersome. Coupled with the OC, the Elisée 350 because many factors affect Fio .
2
ventilator has the capability to lessen the high consump-
tion of oxygen. Indeed, when selected, the “low pressure Limitations of Our Study
O source” option allows oxygen to be supplied from Fio measurement with an internal ventilator sensor is
2
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a low-pressure oxygen source. Oxygen from the low- a limitation. Ventilators were new and specific techni-
pressure source is mixed with air inside the ventilator. cal calibrations were performed 3 months before the
The low-pressure oxygen source can be a line-mounted study. We assumed the oxygen sensor was still in cali-
flow meter or an OC. bration but cannot give an independent verification. We
attempted to mitigate any error by using each ventila-
OCs require little maintenance to provide supplemen- tor with each individual OC. In addition, we also have
tal oxygen. The main limitation for use in critically ill not studied patient oxygenation to determine whether
ventilated patients is the oxygen flow provided. Initially, the delivered Fio change affected arterial oxygenation.
2
FMHS equipped the FSUs with a model of OC limited However, it was not our end point, and we did not pur-
to 5L/min, which was insufficient to supply a ventila- sue this for ethical concerns.
tor. Technological developments led to the production
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of OCs with higher oxygen flow. The SeQual Integra Conclusion
10-OM concentrator typically delivers an Fio up to
2
90% , and is capable of producing up to 10L/min of Our study demonstrates that a compact OC is a feasible
7
oxygen. This model is currently used by the FSUs. alternative to oxygen cylinders to deliver high Fio with
2
the Elisée 350 turbine ventilator. The main difference
Mechanical ventilators used with a high-pressure source when mechanical ventilation is performed with a low-
of oxygen can deliver a precise Fio . When oxygen is sup- pressure oxygen source is that changing ventilator set-
2
plied by low pressure, the Fio delivered to the patient tings or oxygen flow leads to variations in the amount
2
cannot be precisely maintained. Fio is determined by the of delivered Fio . It is important to monitor and adjust
2
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oxygen inlet flow and the total minute volume adjusted flow to maintain desired Fio during such circumstances.
2
on the ventilator. Results show that the respiratory rate
and oxygen inlet flow are the main factors that affect de- Disclosures
livered Fio when a ventilator is used with a low-pressure
2
oxygen source. Changes in I/E and PEEP result in statis- The authors have nothing to disclose.
tically significant differences in delivered Fio , although
2
these differences are probably not clinically relevant be- References
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using a low-oxygen-consumption system. Currently, 7. Bordes J, d’Aranda E, Savoie P-H, et al. Fio delivered by a
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2
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34 Journal of Special Operations Medicine Volume 15, Edition 3/Fall 2016