At the beginning of the movie Platoon, a newly arrived soldier is shown dying of a “sucking chest wound” after being shot in a firefight. Despite the medics’ frantic application of occlusive dressings to a large left chest wound, the soldier’s strangled gasps rapidly subside as he dies. This wound is almost never seen in civilian trauma settings but will be seen fairly frequently in combat settings. It can present in stable patients and pose primarily a wound closure challenge, or it can present in unstable patients who are suffering from hemorrhage, hypoxia, and profound shock. Casualties with open pneumothorax have a hole in their chest wall that has less resistance to airflow than their native airways. Although textbooks talk about a hole “2/3 the diameter of the trachea” – which is somewhat cumbersome to measure at the bedside – a good rule of thumb is that if you can see directly into the chest through the hole, it is usually big enough to cause open pneumothorax .

The deployed surgeon should remember two things about open pneumothorax : first, if the soldier has not bled to death into his chest, he will die from asphyxia unless treated; and second, when something creates a hole in the chest wall big enough to cause an open pneumothorax , it usually means something big went tumbling through the chest itself. The “big” objects can include high-velocity bullets or fragments, large lower velocity fragments, rocks, pieces of equipment, and even live ordnance. Be prepared for surprises on chest X-ray (Fig. 18.2). Operation may be necessary simply to remove large fragments and contamination. In hopefully rare cases, live rockets or grenades may need to be removed in a bunker with an explosive ordnance disposal team at hand, as was done by at least one author of this book.

Treatment priorities remain the same as for all casualties. Although classically listed under “B” in the Advanced Trauma Life Support (ATLS) “ABCDE” algorithm, open pneumothorax is technically an airway problem – with each of the patient’s inspirations, air flows through the hole in the chest wall and into the pleural space rather than through the patient’s airways and into the lungs. Hence, a full-blown open pneumothorax can kill a patient nearly as fast as an airway obstruction. The airway may need to be rapidly secured, particularly if the patient is struggling to breathe and hypoxic. Do not fiddle around placing three-sided occlusive dressings, finding the right-sized plastic material to create a seal, or trying to tape the dressing or Asherman chest seal on a bloody chest in the hope of avoiding intubation. Once the patient is on positive pressure, the airflow resistance differential between that patient’s airways and the chest wall injury is eliminated and the airflow problem fixed. Time can then be taken to more completely assess the casualty, place dressings and chest tubes, and obtain a chest X-ray. The chest wall defect can be covered with an occlusive dressing and a separate chest tube placed to suction. The decision to explore the pleural cavity can then be based on chest tube output and findings on chest X-ray, as is discussed in the chest injury section. Chest CT scan is rarely needed in the acute setting to make this decision. At a minimum, surgeons should explore the chest wall defect to debride devitalized tissue, bone, fragments, clothing, and other wound contaminates and to ensure that intercostal vessels and chest wall muscular bleeders are tied off.

After the casualty’s hemorrhage and contamination have been treated, the inevitable question arises – “what the heck do I do with this big hole in the chest?” When in doubt, keep it simple. A blue towel sandwiched between two Ioban drapes makes a fairly sturdy, nonstick dressing that can be placed between the lung and the chest wall defect. Gauze packing into the defect followed by another Ioban dressing will suffice as a sealed, temporary dressing. With medical bleeding, it may also be necessary to pack the pleural space. Intrathoracic packing with laparotomy pads is safe, if necessary, and will not impair hemodynamics or ventilation. Be sure at least one well-placed, functioning chest tube is present. Alternatively, for selected injuries negative pressure wound therapy can be applied directly to the wound (Fig. 18.3). Nonadherent white sponge, when available, can be used against the lung, although sterile petrolatum gauze can also be used between lung and black sponge. Again, at least one chest tube should be in place. With this technique, sealing of the lung to completely close the pleural cavity from the wound can be affected, usually in just 3–5 days of negative pressure therapy.

In either case, evacuation of the patient to a higher level of care is possible with this temporary chest wall closure. Once the patient is stable, small defects can undergo delayed primary closure in layers based on the quality of tissue present and absence of contamination. Usually, enough chest wall musculature is present to mobilize for a relatively tension-free flap closure over the defect. Larger defects may require a synthetic or bioprosthetic patch or pedicled myocutaneous flap  – these interventions should generally be reserved for higher levels of care, but you may have to perform these procedures at your forward facility for local national patients.

Although this is classically considered an injury of blunt trauma , many of the mechanisms in modern combat can cause significant chest wall disruption with the classic resultant flail chest segment and underlying pulmonary contusion . Unlike the typical civilian low-velocity missile wounds, combat mechanisms such as high-velocity missiles, rocket-propelled grenades, or explosive devices can all disrupt enough of the chest wall to cause flail. Modern body armor can often turn what would normally be a fatal penetrating chest wound into more of a blunt-type flail segment (Fig. 18.4). While there may not be significant external chest wall trauma, behind armor blunt trauma can result in significant injury underneath. Remember that while it may be associated with significant pain the primary problem is usually not the flail segment; it is the underlying lung injury and pulmonary contusion. The diagnosis is usually readily apparent from close examination of the wound and chest X-ray. Remember that you will not see the typical “paradoxical” motion of the flail segment if the patient is on positive pressure ventilation.