Page 48 - Journal of Special Operations Medicine - Fall 2016

Fraction of Inspired Oxygen Delivered by
Elisée 350 Turbine Transport Ventilator With a
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Portable Oxygen Concentrator in an Austere Environment

Erwan d’Aranda, MD; Julien Bordes, MD; Boris Bourgeois, MD;
Jared Clay, MD; Pierre Esnault, MD; Pierre-Julien Cungi, MD;
Philippe Goutorbe, MD; Eric Kaiser, MD; Eric Meaudre, MD

ABSTRACT
Background: Management of critically ill patients in The French Army is often engaged in overseas operations
austere environments is a logistic challenge. Availabil- in remote or austere environments such as Afghanistan
ity of oxygen cylinders for the mechanically ventilated and Africa. Providing medical support to these opera-
patient may be difficult in such a context. One solution tions is challenging because of the significant distance
is to use a ventilator able to function with an oxygen from France and lack of reliable medical resources lo-
concentrator (OC). Methods: We tested two Elisée cally. The French Military Health Service (FMHS) has
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350 ventilators paired with SeQual Integra 10-OM oxy- gained notable experience in these environments. Its
gen concentrators (OC) (Chart Industries, http://www guiding principles are frontline medical care, frontline
.chartindustries.com) and evaluated the delivered frac- resuscitation and surgical care, and early secondary med-
tion of inspired oxygen (Fio ). Ventilators were con- ical evacuations. One strategy the FMHS uses to achieve
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nected to a test lung and Fio was measured and indicated these is the forward surgical unit (FSU), comprising a
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by the ventilator. Continuous oxygen was generated by light, mobile structure consisting of six tents with their
the OC from 0.5L/min to 10L/min, and administered by own electrical power and a team of one general surgeon,
the specific inlet port of the ventilator. Several combina- one orthopedic surgeon, one anesthesiologist, and nine
tions of ventilator settings were evaluated to determine nurses. The FSU permits anesthesia, intensive care, and
the factors affecting the delivered Fio . Results: The Eli- damage control surgery closer to the point of injury. The
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sée 350 turbine ventilator is able to deliver a high Fio surgical team is capable of performing 10 operations per
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when functioning with an OC. However, modifications day during a 2- to 4-day period. Recently, a vital sur-
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of the ventilator settings such as an increase in minute gery unit (VSU) has been developed and made available
ventilation, inspiratory-to-expiratory ratio, and posi- to Special Forces. The VSU is manned by one general
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tive end-expiratory pressure affect delivered Fio despite surgeon, one anesthesiologist, and two nurses, and in-
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steady-state oxygen flow from the concentrator. Con- corporates a very light, mobile structure (1,000kg; 4m ).
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clusion: OCs provide an alternative to oxygen cylinders This unit can be deployed under a tent, on a surface
for delivering high Fio with a turbine ventilator. Nev- ship, or directly in a tactical transport aircraft.
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ertheless, Fio must be monitored continuously, since it
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decreases when minute ventilation is increased. The contexts in which these structures operate require
mobility of their equipment and make the oxygen sup-
Keywords: mechanical ventilation; oxygen delivery; oxygen, ply hazardous and difficult to support. The use of cum-
low-flow; oxygen concentrator; Elisée 350 bersome oxygen production modules is not possible in
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such settings. FSUs and VSUs are equipped with limited
stocks of oxygen cylinders, which might be quickly ex-
hausted in case of massive combat casualties; thus, por-
Introduction
table oxygen concentrators (OC) have been proposed as
a solution for mobile oxygen production. Furthermore,
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Mechanical ventilators commonly use a high-pressure medical oxygen is in limited supply in the developing
oxygen source for oxygen delivery; however, availability world. As such, OCs have been proposed as a suitable
of this resource can be challenging in austere environ- option in Africa and in mountainous environments.
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ments. High-pressure oxygen is standard and required for However, the literature on mechanical ventilation with
precise control of the fraction of inspired oxygen concen- an OC is lacking, especially on reliability of delivered
tration (Fio ) during mechanical ventilation. Compressed Fio with this oxygen source. Two studies focused on
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oxygen is not always available early in military deploy- the delivered Fio when a ventilator was coupled with an
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ments or during disaster response. OC. Rodriquez et al. described the use of a portable
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