Page 161 - JSOM Fall 2020

Development of a New Vented Chest Seal Dressing
for Treatment of Open Pneumothorax

Andrew Hoggarth, BSc Hons, MSc*; Matthew Grist, MChem, PhD;
Bryony Board, BSc Hons; Toni Murch, MCPara

ABSTRACT
The most common life-threatening complications from both with thoracic trauma have tension pneumothorax at the time
blunt and penetrating thoracic injury are hemothorax, pneu- of death. 5
mothorax, or a combination of both. New guidelines, set out
by the Tactical Combat Casualty Care (TCCC), advises that Reported data indicate that effective management of com-
vented chest seal dressings are used to manage open or sucking bat-related thoracic trauma is key to increasing survival. This
chest wounds. Designing out risk is a fundamental criterion for document assesses the requirements for vented chest seal
ensuring the optimal performance of a device is obtained that dressings and proposes a new design to mitigate existing risk
offers the casualty the greatest chance of survival. Two key factors.
areas of risk in the application of vented chest seal dressings
are adhesion failure and vent failure. This study assesses a new Pneumothorax
design of vented chest seal dressing for both adhesion and vent Pneumothorax is defined as the presence of air or gas in the
profile. The development of this new design for a vented chest pleural cavity. The clinical impacts of this result in various
seal has been tested for adhesion and venting properties and degrees of collapse of the lung on the affected side. As a con-
shown to have performance criteria suitable for the treatment sequence, pneumothorax can impair oxygenation and/or ven-
of open pneumothorax and design features that minimize the tilation. Open pneumothorax occurs in which gas enters the
risk of product failure during use. pleural space other than from a ruptured or lacerated lung.
This can be through an open wound in the chest wall. Closed
Keywords: thoracic injury; hemothorax; pneumothorax; chest pneumothorax refers to gas accumulation in the pleural space
seal dressing in the absence of an open chest wound.

Tension pneumothorax is a life-threatening condition that de-
velops when air is trapped in the pleural cavity under positive
Introduction pressure. This pressure displaces the mediastinal structures, re-
Over multiple decades, combat-related thoracic trauma has sulting in compromised cardiopulmonary function. One of the
been a major contributor to the morbidity and mortality of key emergency requirements once this occurs is the recognition
the casualties. The mechanisms of trauma can be grouped of tension pneumothorax to help prevent death.
into penetrating, blunt, and blast injuries. The most common
life-threatening complications from both blunt and pene- Current Guidelines
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trating thoracic injury are hemothorax, pneumothorax, or a The August 2019 guidelines August 2019 by the TCCC still
combination of both. Pneumothorax is reported as the most uses the 2013 guideline changes for chest seal dressings and
common injury sustained in chest trauma, occurring in about advises that “all open and/or sucking chest wounds should be
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20% of patients. In the late 1980s and early 1990s, a study treated by immediately applying a vented chest seal to cover
of 3640 military casualties concluded that 10.7% were treated the defect. If a vented chest seal is not available, use a non-
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for chest injuries. Later studies referencing conflict in Iraq and vented chest seal.” For nonvented chest seals, if the casualty
Afghanistan report 8.6% to 16% of casualties obtaining some develops increasing hypoxia, respiratory distress, or hypoten-
form of chest trauma. 3 sion and a tension pneumothorax is suspected, treat by burp-
ing (the temporary removal of the dressing and resealing or by
One publication indicated that approximately 10% to 30% of needle decompression) or removing the dressing or by needle
patients transported to Level 1 trauma centers in the United decompression.
States receive prehospital decompressive needle thoracosto-
mies. This may be a sign of the level of tension pneumothorax Design Requirements for Vented Chest Seal Dressings
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but is not definitive and probably excessive. A further review Designing out risk is a fundamental criterion for ensuring the
of military deaths reports that up to 5% of combat casualties optimal performance of a device is obtained that offers the
*Correspondence to andrew.hoggarth@medtrade.co.uk
Mr Hoggarth, Dr Grist, Mr Board, and MR Murch are affiliated with Medtrade Products Ltd, Crewe, UK.

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