Approach to penetrating chest injury: Clinical sciences

Penetrating chest injury is a dangerous type of trauma that commonly occurs from gunshot wounds, stabbings, and impalement. For any patient presenting with penetrating injury to the chest, you must have a high clinical suspicion for life-threatening injuries to heart, lungs, and the great vessels. Timely diagnosis and immediate intervention is key to reducing morbidity and mortality. In clinical practice, the majority of penetrating chest injuries can be managed nonoperatively, but if left untreated, even a minor wound can become fatal in a short span of time.

Alright, your first step in evaluating a patient presenting with a penetrating chest injury is to perform a primary survey by assessing their ABCDE, which will help you determine if the patient is stable or unstable. Start by evaluating and securing the airway. Stabilize the C-spine with a C-collar to immobilize the spine, keeping in mind that the spinal cord could be injured from the penetrating trauma. If needed, intubate or create a surgical airway like a cricothyroidotomy. Then, check for breathing, ensure adequate ventilation, provide supplemental oxygen, and auscultate the lungs for bilateral breath sounds.

Next, obtain two large bore IVs or an intraosseous line and start fluid resuscitation including transfusion of blood products if massive hemorrhage is suspected. At the same time, continuously monitoring vital signs including heart rate, blood pressure, and oxygen saturation. Then, assess disability, or neurologic status, by calculating the patient’s GCS, and perform a pupillary exam and a neurologic exam. Lastly, expose the patient by removing all clothing and bandages to ensure no injuries are missed. After examining the patient, place a warm blanket over them to avoid hypothermia.

Okay, let’s first discuss unstable patients. Once you have completed the primary survey and initiated the acute management, your next step is to perform the secondary survey, which is a head to toe physical exam. The focus of the secondary survey is to look for life-threatening injuries and signs of impending hemodynamic collapse. In clinical practice, adjunctive tests like labs and diagnostic imaging are also done during the secondary survey, but a thorough physical exam is the most important tool to help you identify the life-threatening injury for this type of trauma.

Alright, the first condition to look for is tension pneumothorax. Physical exam will typically reveal hypotension, jugular venous distention, and tracheal deviation, as well as absent lung sounds on auscultation and resonance to percussion of the chest wall. Depending on the injury, you might even see an open sucking chest wound. These are classic features of a tension pneumothorax, which occurs when the penetrating injury tears the pleural lining of the thoracic cavity creating a “one-way valve” effect.

The air enters through the tear and accumulates within the pleural space with each breath. As the cavity fills with the trapped air, the lung becomes compressed and the mediastinum is pushed towards the opposite side. If left untreated, mediastinal structures, like the inferior vena cava and the heart, become further compressed, leading to a marked decrease in venous return and cardiac output, resulting in obstructive shock. Remember, tension pneumothorax is a clinical diagnosis, so you should go directly to treatment such as needle decompression or tube thoracostomy.

Okay, let’s discuss massive hemothorax! This typically occurs when there’s an injury to a major cardiovascular structure like the heart, great vessels, or intercostal arteries, and can quickly lead to at least a third of a patient’s blood volume accumulating within the thoracic cavity! On exam, you can expect to find hypotension, decreased lungs sounds on auscultation, and dullness to percussion over the affected side. If these are your findings, consider a hemothorax.

Your next step is to obtain an extended focused assessment with sonography in trauma, or e-FAST, which will typically show dense fluid within the pleural cavity. Then, place a tube thoracostomy right away to drain the blood so the lung can inflate.

An immediate output of blood greater than 1500 milliliters is diagnostic of a massive hemothorax. This is a surgical emergency that needs immediate operative intervention!

Moving on to cardiac tamponade. This occurs when blood accumulates in the pericardial sac. As blood fills the pericardial space, it restricts and pushes on the heart, decreasing its ability to fill, and ultimately reducing cardiac output.

And because the pericardial space is relatively small, even a small accumulation of blood can quickly lead to cardiogenic shock.

So, on exam, you will likely find Beck triad, which is hypotension, jugular vein distension, and muffled heart sounds. This should lead you to consider a cardiac tamponade. Then, obtain an e-FAST to visualize the fluid within the pericardium.