Page 25 - JSOM Summer 2025

Methods
The PICO template was used to determine the keywords and
inclusion and exclusion criteria:

• Population: Prehospital emergency care in a military and
austere environment, trauma patients. FIGURE 1 Tusk mask: non-
• Intervention: Oxygenation by DTM. rebreathing mask (NRM) with
• Control: Other oxygenation methods. two corrugated tubing ISO 22
length 10cm.
• Outcomes: Clinical efficiency, technical characteristics.
This PICO process resulted in the following keywords or
MeSH-words: ‘oxygen inhalation therapy,’ ‘hypoxia,’ ‘hypox-
emia,’ ‘multiple trauma,’ ‘oxygen supply,’ ‘oxygen supplies,’
‘tactical environment,’ and ‘Double Trunk Mask.’ These key-
words were used in PubMed, Embase, Web of Science, and
Oxford databases. two openings on the mask’s lateral sides. Tubes known as
trunks (corrugated tubing 22mm, approximately 15–20cm
The inclusion criteria were: evaluated the prehospital care in long when dedicated to adults (AirLife Corrugated Tubing
a civilian or military environment and a real-life setting; pub- [Vyaire Medical, Mettawa, IL]) are fixed in these lateral open-
lished in English, Dutch, or French; randomized controlled ings (Figure 2). 12,15,21 The patient receives oxygen only through
trial (RCT), cohort study, systematic review, or meta-analysis; an additional NC. In daily practice, the DTM is simply placed
published between January 1990 and December 2023. Edito- on top of the NC, and the DTM acts as an O reservoir. Thanks
2
rials and congress proceedings were excluded. to this configuration, the additional tubes (±75cm³ for each
trunk and ±50cm³ for the mask) increase the dead space of
The title and abstract of these articles were screened for in- the system. This setup leads to enhanced O delivery because
2
clusion criteria. When there was uncertainty if the inclusion the inhaled O volume is greater than with traditional NC use.
2
criteria were fulfilled, the full text was screened.
Basic Physical Principles Underlying DTM Performance
Results In spontaneous ventilation and during oxygen therapy at low
flow, the FIO administered is dependent on three parameters:
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Fifteen articles were considered eligible for this analysis. Thir- oxygen flow, inspiratory flow of/to the patient, and dead space
teen had a prospective design, and 10 had a randomized cross- of the mask.
over design.
We can add the supplementary oxygen volume inspired if the
DTM: An Innovative Oxygen Delivery System system has an efficient oxygen bag, such as an NRM. How-
The DTM derives from a mask originally described by Farias ever, NRM are rarely highly effective in delivering high con-
and Hnatiuk, 19,20 named the tusk mask. The tusk mask was centrations of oxygen. 8,22–24
composed of two side tubes called tusks (corrugated tubing
22mm, approximately 10cm long) (Figure 1) fixed to an NRM. When using conventional oxygenation systems, during the ex-
The current DTM consists of a classic aerosol mask (Resp-O piratory phase, the O from the NC that is not entering the
2
2
Aerosol Masks [Dynarex Corporation, Montvale, NJ]) with nasal cavities is lost to the atmosphere. With the DTM, this
(A) (B) FIGURE 2 (A) Aerosol mask with two
corrugated tubes (ISO 22) length 15–20cm;
(B) The assembled double-trunk mask
(DTM); (C) Left – Subject with nasal cannula
(NC); Right – The DTM placed over the NC;
(D) Application of the DTM in operational
medicine.

(D)

(C) (C)

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