Page 17 - JSOM Fall 2024

A unique feature of BENGI is the spoken audio cues. In the inspiration and exhalation and enormous potential for lung
same way that cardiopulmonary resuscitation (CPR) feedback hyperinflation. Even experienced medical personnel with ex-
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devices improve CPR training, audiovisual V feedback de- tensive training are vulnerable to environmental factors such
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vices should be adopted as part of a more comprehensive man- as artillery, noise, distractions, lighting, and adverse weather
ual ventilation training method to reduce hyperventilation. 35–37 conditions that can challenge precise manual ventilation. Be-
However, in far-forward, high-risk military environments, the sides hyperventilation, it is important to note that traumatic
noise generated by narration guidance may not be wanted, and thoracic injuries, especially those affecting the chest wall or
the BENGI’s mute functionality would be useful. Future work rib fractures, can elicit intense pain that leads to hypoventi-
could include further volume adjustment functionality. Addi- lation, known as splinting (reduced inspiratory effort, char-
tionally, in our experience, the BENGI’s battery life would last acterized by reduced lung expansion and compromised gas
approximately 90 minutes with constant use. Certain scenar- exchange). Splinting can decrease breathing rate, tidal volume,
ios involving prolonged manual ventilation in far-forward en- or both, often with serious consequences on respiratory func-
vironments may last longer. Therefore, in the future, research tion. In battlefield settings, splinting can result in inadequate
on approaches to improve battery life without sacrificing the ventilation and respiratory failure leading to hypoventilation
device’s mobility is warranted. and increased risks of complications such as pneumonia. Be-
sides ‘splinting,’ incomplete management of pain in thoracic
Study limitations include: (1) simulation deviations from re- trauma can lead to hypoventilation via an impaired cough re-
al-life scenarios;(2) potential participant behavior changes flex, which is essential for clearing airway secretions of accu-
due to study awareness; (3) unintentional exclusion of certain mulated mucus and debris and further increasing respiratory
healthcare professional groups; (4) lack of participant expe- stress and risk of infections. If splinting-induced hypoventila-
rience and training data; (5) assessment of BENGI use with tion reduces respiration, it can lead to serious patient stress,
varying levels of circuit air leak; (6) lack of testing with other morbidity, and mortality. In such cases, BENGI could signifi-
airway devices, including bag-valve-mask and supraglottic cantly maintain respiration despite the effects of splinting in
airway devices; (7) absence of PEEP valve impact assessment; conscious individuals.
(8) potential rebreathing effects with BENGI; (9) unexplored
effects on rescuer’s grip and biomechanics; (10) lack of battery Risks associated with battlespace lung hyperinflation during
life testing; and (11) not measuring frequency of audio cue ac- manual ventilation can be extreme, primarily reflecting the
tivation and its impact on performance. The BENGI also pres- impact of lung hyperinflation on lung structure, pathophysi-
ents additional technical limitations, including the addition of ology, and clinical outcomes. Excessive pressure or mechanical
dead space (of approximately 20mL to the circuit), which is work during manual ventilation can cause barotrauma, pneu-
particularly detrimental in neonatal resuscitation scenarios; mothorax, alveolar rupture and impaired gas exchange, and
and a lack of onboard metronomic audio cues for neonatal respiratory distress, as additional risks. The limitations and
RR delivery. Future directions involve testing BENGI in more need for rapid response in a battlespace environment intensify
realistic scenarios, including team-based resuscitation simula- these risks making effective manual ventilation a critical but
tions with mask use. challenging aspect of battlefield medical care. Because BENGI
can immediately and persistently minimize or eliminate such
The Prolonged Casualty Care guidelines outline the import- forms of lung injury, such devices represent an important train-
ant role manual ventilation plays in the far-forward casualty ing tool for military medical personnel whose patients require
environment. Manual ventilation is the preferred method of precise and reliable ventilation techniques. The use of guided
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ventilation when mechanical ventilators, supporting equip- ventilation equipment and strategies like BENGI to mitigate
ment, such as a reliable oxygen source or electrical power, or battlespace challenges is essential to ensure patient safety and
the personnel with the expertise to operate mechanical ven- optimize respiratory support in dynamic and demanding bat-
tilation safely is not available. This is particularly relevant in tlefield conditions.
Special Forces and large-scale combat operations that occur
in austere environments. In such an environment, life-saving Conclusion
medical aid—including ventilation—may be provided by ei-
ther personnel with only basic medical training or by small The use of BENGI significantly improved tidal volume and
forward surgical teams with access to only ultra-mobile med- RR accuracy, and consistency during manual ventilation were
ical supplies. 39–41 Such life-saving aid may need to be provided significantly improved by BENGI use in a randomized cross-
for an extended time if evacuation capabilities are limited. The over manikin simulation study. Simple and intuitive audiovi-
BENGI and other audiovisual V feedback devices are porta- sual tidal volume feedback devices such as the BENGI may be
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ble devices that can aid in providing consistent manual venti- valuable during both clinical events, like resuscitation scenar-
lation until the patient can be transported to a location where ios, and in manual ventilation training environments.
more definitive means of ventilation can be acquired.
Acknowledgments
When consistent manual ventilation is not provided, lung hy- The authors would like to acknowledge Kimberly Hutchinson
perinflation during manual ventilation, either in the battlespace and Elizabeth Caskey for assisting in the development of the
or in civilian medical emergencies, remains a common high- Institutional Review Board protocol.
risk clinical phenomenon, which arises from urgent stresses
while under fire, or during evacuation, time pressures, and Author Contributions
the need to rapidly implement basic medical equipment. The LAW, BSM, GFS, SAC, and JSA conceived of the study. LAW,
often desperate need to rapidly provide respiratory support, BSM, and JSA conducted the formal analysis. LAW and BSM
particularly in high-stakes battle scenarios, can lead to poor curated the data. LAW, BSM, and JSA wrote the original draft.
application of manual ventilation techniques, with inadequate LAW, BSM, and JSA reviewed and edited the draft. GFS and

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