Introduction:

The most serious form of thoracic injuries can cause either a tension pneumothorax (TPX), a hemothorax, or both. Furthermore, in the civilian sector 10.5% of blunt trauma patients, and up to 40% of penetrating trauma patients are reported to have a TPX, and this condition is known to be a leading cause of preventable deaths in battlefield combatants. TPX is rare, but it can be fatal, resulting in traumatic cardiac arrest. With ongoing evidence-based research, investigators strive to determine best practices for managing a TPX and hemothorax. Thus, clinical practitioners are encouraged to stay up-to-date with TPX clinical practice guidelines.

A 2017 working group from the Committee on Tactical Combat Casualty Care (CoTCCC) reviewed the evidence for preventing and managing a TPX since the last update was done in 2012. Some other reasons for the TPX update were: (1) Case reports of two combat fatalities with evidence of TPX on autopsy with no evidence of any needle decompression (NDC) attempts, nor were there any fatal injuries found; (2) There was a lack of consensus in the literature about the sequence of observing TPX signs and symptoms when a NDC should be used; and (3) The 2012 TCCC TPX guidelines did not address what constitutes a successful NDC, nor did it stipulate the necessary steps to take if a NDC fails to relieve the signs and symptoms of a suspected TPX. Thus, it is our aim to summarize the key changes in the current Tactical Combat Casualty Care (TCCC) guidelines for managing TPX. Also, see a Podcast presentation with Frank K. Butler Jr., MD, who discusses the management of TPX in TCCC.

It is beyond our scope to present the pathophysiology of traumatic TPX, but an acceptable definition is an injury (blunt or penetrating) to the lung that results in air leaking into the pleural space and being trapped there with a secondary increase in intrapleural pressure. In the early injury phase, the victim can compensate physiologically, but eventually a progressive respiratory failure and/or shock will develop. This in turn results in cardiopulmonary collapse with traumatic cardiac arrest as the terminal event, if not treated effectively to decompress the chest.


Key Changes to the 2018 TCCC TPX Guidelines:

The following summarizes the key changes:

(1) Continues the aggressive approach to suspecting and treating tension pneumothorax based on mechanism of injury and respiratory distress that TCCC has advocated for in the past, as opposed to waiting until shock develops as a result of the tension pneumothorax before treating.

(2) Adds additional emphasis to the importance of the current TCCC recommendation to perform needle decompression (NDC) on both sides of the chest on a combat casualty with torso trauma who suffers a traumatic cardiac arrest before reaching a medical treatment facility.

(3) Adds a 10-gauge, 3.25-in needle/catheter unit as an alternative for needle decompression.

(4) Designates the location at which NDC should be performed as either the lateral site (fifth intercostal space [ICS] at the anterior axillary line [AAL]) or the anterior site (second ICS at the midclavicular line [MCL]).

(5) Adds two key elements to the description of the NDC procedure: insert the needle catheter unit at a perpendicular angle to the chest wall all the way to the hub, then hold the needle/catheter unit in place for 5 to 10 seconds before removing the needle in order to allow for full decompression of the pleural space to occur.

(6) Defines what constitutes a successful NDC.

(7) Recommends that only two needle decompressions be attempted before continuing on to the “Circulation” portion of the TCCC guidelines.

(8) Adds a paragraph to the end of the Circulation section of the TCCC guidelines that calls for consideration of untreated tension pneumothorax as a potential cause for shock that has not responded to fluid resuscitation.

(9) Adds finger thoracostomy (simple thoracostomy) and chest tubes as additional treatment options to treat suspected tension pneumothorax when further treatment is deemed necessary after two unsuccessful NDC attempts.

The current TCCC guidelines are found on the Deployed Medicine website. The section for managing a TPX is located in the Tactical Field Care, Section 5, Respiration-Breathing. In addition, see the TCCC video overview of chest trauma that explains how a pneumothorax and a TPX develops, and the current clinical management recommendations based on the 2018 update. Also, see Table 1 that lists the 11 questions addressed in this TPX update, and the final Recommendations and Grades for the strength of evidence.

TPX Training:

It is well documented that many studies report high success rates for needle thoracostomy, but numerous others report inferior success rates to decompress the chest. Consequently, it is recommended to review training protocols for quality assurance and improvements based on a minimum of five factors: 1) Not using current recommended NDC equipment; 2) NDC not conducted in the correct anterior or lateral anatomical locations to achieve chest decompression; 3) Anterior NDC performed too medially with penetration inside the “cardiac box” resulting in an iatrogenic mediastinum injuries; 4) NDC device failures such as catheter clotting, kinking, dislodgement; 5) Not using recommended pediatrics NDC procedures for anterior and lateral anatomical sites; and 6) Not using both low and high fidelity simulations to train practical teaching scenarios in the laboratory and field settings during intense day and night training using experienced trainers. CoTCCC recommends a cadaver-based NDC training program since this has been found to result in improved performance. Here are two TPX training videos that were developed to support the updated TCCC curriculum – NDC and the other for chest seals.

Implications for Wilderness Medicine Practitioners:

The robust principles of TCCC guidelines for managing a TPX are equally applicable to trauma victims in any civilian setting. Previously, Lanny Littlejohn MD, a current CoTCCC member, made recommendations for managing chest trauma in the wilderness setting as published in the Wilderness & Environmental Medicine 2017 Special Edition titled, “Tactical Combat Casualty Care: Transitioning Battlefield Lessons Learned to Other Austere Environments."

Final Thoughts:

Norman McSwain MD, a trauma surgeon, CoTCCC member, and the founder of NAEMT’s Prehospital Trauma Life Support program, would frequently remind us all during our CoTCCC meetings by stating to always exercise principles vs. preferences as a fundamental critical concept in prehospital trauma care. When in the backcountry, or in any other trauma setting, and when indicated, the principle is to effectively manage a TPX and decompress the chest in a victim with hypotension, shock, and traumatic cardiac arrest. The preference is what gear you will carry to manage chest trauma, and how you choose to achieve the objective, i.e., with an occlusive or vented chest seal, and a needle, finger, or a chest tube thoracostomy. Finally, to minimize unsuccessful chest decompression attempts, and related iatrogenic complications, a robust training program is essential with high fidelity simulation models, experienced mentors/trainers, and with a quality assurance oversight program. Otherwise, you are effectively “up a creek without a paddle”, especially in a limited resource environment.