Page 86 - JSOM Fall 2021

Kheirabadi et al. surgically created an open pneumothorax Study heterogeneity preventing meta-analysis and the lack of
and a catheter was placed percutaneously into the intrapleural clinical trials available for review are also limitations of this
cavity to facilitate the injection of air and intrapleural pres- analysis. The review methodology had limitations, including
20
sure monitoring. One of the two randomized chest seals was the inability to present quantitative summaries of results given
then placed over the open pneumothorax after 5 minutes in the studies’ heterogeneity, as well as the use of a fundamental
the open atmosphere. Every 5 minutes, 200mL of air was in- comparative analysis as compared with a formal, previously
jected into the intrapleural space, and data were recorded until validated method of analysis. The paucity of literature on this
either the study-defined criteria were met, or the volume of topic over the past 28 years prevented the inclusion of every
air injected into the intrapleural space equaled the total lung commercially available chest seal. Despite these limitations,
capacity of the swine. At the completion of the iteration, the the search strategy was quite broad. It allowed for the iden-
presence or absence of a tension pneumothorax was confirmed tification of a full spectrum of topics relevant to chest seals
with a radiograph. over an extensive time period. It also critically evaluated the
methodology of eligible studies and did not incorporate re-
All iterations with the nonvented Halo Chest Seal resulted sults from studies with inappropriate design or phenomena of
20
in failure and the development of a tension pneumothorax. interest.
All iterations with the vented Bolin Chest Seal were a success,
even when the maximum volume of air had been reached. 20
Conclusion
Although chest seals are recommended in civilian and military
Discussion
prehospital medicine to improve patient survival, current evi-
This study’s key finding was a paucity of quantitative exper- dence concerning the efficacy of these devices is limited. Fur-
imental design research focusing on chest seal adherence and ther experimental, quantitative research is needed to clarify
ability to prevent tension pneumothorax following penetrat- which commercially available chest seals are the most effective
ing trauma. Of 682 eligible references, only six met review and provide patients the best possible chance for survival.
inclusion criteria: 595 did not assess adherence or vent/valve
function; 32 involved indications other than penetrating chest Acknowledgments
trauma; and 8 were qualitative and narrative. Additional re- We would like to thank Karen Barton, MSLIS, former research
view complications for determining which chest seals have librarian at the University of Texas Health Science Center San
superior adherence and ability to prevent tension pneumo- Antonio, for assistance with the electronic database searches.
thorax development were heterogeneity in study methods and
reported outcomes, the use of swine in five of the laboratory Disclosures
studies, and the absence of relevant clinical trial data. The authors report no conflict of interests.

This review and synthesis of the limited data identified the Hy- Author Contributions
fin Vent Chest Seal and Russell Chest Seal, both nonocclusive RP conducted the initial literature search. RP, A., and LB de-
chest seals, as being the recommended chest seals. This was veloped the study design and methods. RP, MQ, PA, and LB
the recommendation by consensus of the reviewed studies for conducted the data collection, analysis, interpretation. RP
the treatment of open pneumothoraces. It is unknown whether wrote the initial manuscript. MQ, PA, and LB provided criti-
these two chest seals would remain as the top performers if all cal revisions.
commercially available devices were tested across all the rele-
vant studies. While the Hyfin Vent Chest Seal lost adherence in References
Kheirabadi et al.’s 2017 study, its ability to continue function- 1. Ivey KM, White CE, Wallum TE, et al. Thoracic injuries in US
ing as a three-sided dressing and preventing the predetermined combat casualties: a 10-year review of Operation Enduring Free-
dom and Iraqi Freedom. J Trauma Acute Care Surg. 2012;73(6
tension pneumothorax-related criteria led to it being consid- Suppl 5):S514–5519.
ered a success. It is for this reason that it is still considered 2. Davis JS, Satahoo SS, Butler FK, et al. An analysis of prehospital
16
eligible to be included in the consensus recommendation. deaths: Who can we save? J Trauma Acute Care Surg. 2014;77(2):
213–218.
Study Limitations 3. Smith ER, Shapiro G, Sarani B. The profile of wounding in civilian
There were limitations within all the included studies. Supinski public mass shooting fatalities. J Trauma Acute Care Surg. 2016;81
(1):86–92.
et al. was the only study with human participants. Swine hair 4. Butler FK, Bennett B, Wedmore CI. Tactical Combat Casualty
13
and skin differ from human hair and skin enough to create a Care and wilderness medicine: advancing trauma care in austere
significant limitation. The relatively shorter, stiffer, and more environments. Emerg Med Clin North Am. 2017;35(2):391–407.
coarse hairs of the swine may affect how any device adheres to 5. Littlejohn LF. Treatment of thoracic trauma: lessons from the bat-
unshaven skin. The thicker and less pliable swine skin may affect tlefield adapted to all austere environments. Wilderness Environ
Med. 2017;28(2S):S69–S73.
how an adhesive device remains adhered to a moving chest wall. 6. American College of Surgeons. Advanced trauma life support
Swine do not perspire, and regardless of the investigator’s in- (ATLS student course manual). 10 ed. Chicago, IL: American
®
th
tent, real battlefield and prehospital conditions are not easily re- College of Surgeons; 2018.
produced during simulation. Kheirabadi et al.’s 2017 study was 7. Committee For Tactical Emergency Casualty Care. Tactical Emer-
the only study to simulate bleeding into the wound tract, which gency Casualty Care (TECC) guidelines for BLS/ALS medical pro-
could be seen as a limitation within this study or a limitation of viders. 2019 March. http://www.c-tecc.org/images/4-2019_TECC
16
the other five studies that lacked a bleeding wound tract. The _ALS_BLS_Guidelines_.pdf. Accessed 26 April 2021.
authors of this review felt that blood moving through the chest 8. Committee on Tactical Combat Casualty Care. TCCC guidelines
for medical personnel. 2020 November. https://books.allogy.com
seal is a possibility under combat conditions and therefore that /web/tenant/8/books/b729b76a-1a34-4bf7-b76b-66bb2072b2a7/.
the Kheirabadi et al. study provided realistic conditions. 16 Accessed 26 April 2021.

84 | JSOM Volume 21, Edition 3 / Fall 2021