Approach to blunt chest injury: Clinical sciences

Blunt chest injury commonly occurs from motor vehicle accidents, falls, and assault, and can range in severity from mild to life-threatening. Most of the blunt chest injuries are mild and can be managed non-surgically. However, severe injuries can become rapidly fatal, so timely diagnosis and immediate surgical intervention is key. These life-threatening injuries include tension pneumothorax, massive hemothorax, and aortic rupture, as well as cardiac tamponade and thoracic vertebral fracture. Other urgent but less serious injuries include rib fractures, flail chest, sternal fracture, thoracic vertebral fractures, and tracheobronchial and esophageal injuries, in addition to parenchymal lung injuries, hemopneumothorax, blunt aortic injury, and diaphragmatic injury.

Alright, your first step in evaluating a patient presenting with blunt chest injury is to perform the primary survey using the ABCDE assessment. First, secure the Airway while stabilizing the cervical spine. Have a low threshold for endotracheal intubation or a surgical airway, especially if the patient cannot protect or maintain their own airway. Once you’ve secured the airway, ensure adequate Breathing or ventilation by providing supplemental oxygen.

Next, assess Circulation and obtain 2 large bore IVs or IO access while continuously monitoring vitals, such as heart rate and blood pressure. Then, assess Disability and neurologic status by calculating their GCS and examining the pupils and spine, as well as for sensory and motor deficits. Make sure to ensure spine immobilization until spinal injury has been ruled out. Finally, Expose the patient and remove all clothing to assess for any other associated injuries, and cover the patient with warm blankets to prevent hypothermia.

Once you’ve determined your patient is unstable, your next step is to quickly perform the secondary survey, which is a head-to-toe exam, and adjunctive tests like an e-FAST exam to look for any life-threatening injuries and signs of impending hemodynamic collapse. Keep in mind, unstable patients might not be able to report symptoms or provide a history. Luckily, the majority of life-threatening conditions can be detected on physical exam and adjunctive tests.

Let’s dive into our first diagnosis, tension pneumothorax. This occurs when a tear in the pleural lining causes air to accumulate in the pleural space, compressing the lung and pushing upon other mediastinal structures like the heart and trachea. On exam, you can expect to find hypotension, jugular venous distention, tracheal deviation, absent lung sounds on auscultation, along with resonance on percussion of the chest wall. These are classic findings of a tension pneumothorax and obstructive shock. Needle decompression or a tube thoracostomy should be performed immediately to relieve the pneumothorax.

Our next life-threatening injury is massive hemothorax. This occurs when an injury to the heart, thoracic aorta, or great vessels leads to a large volume of blood accumulating in the thoracic cavity. Physical exam will show hypotension, absent breath sounds and dullness on percussion over the affected side. Additionally, you might see fluid within the pleural cavity on e-FAST, leading you to consider a hemothorax. Then, place a tube thoracostomy to relieve the blood and reinflate the lung. If there’s an immediate output of blood greater than 1500 cc, your diagnosis of a massive hemothorax is confirmed. This is an indication for emergent operative intervention.

Next up we have aortic rupture. This injury is often associated with a high force and speed mechanism, and most patients die before arriving at a hospital. Those who make it to the hospital might present after losing vitals on the field with CPR ongoing. Patients are likely to be unresponsive and hypotensive, often in extremis.

However, if they show signs of life, an emergency or resuscitative should be performed immediately at the bedside. The goal of the thoracotomy is to directly visualize the injury and provide temporizing measures as fast as possible. Visualization of the ruptured aorta will establish your diagnosis of aortic rupture. Of note, even if the injury is repaired, mortality rates remain high.

Now let’s move on to cardiac tamponade. This injury occurs when blunt trauma causes bleeding into the pericardial sac. As blood accumulates, it restricts the heart, causing obstructive shock. On physical exam, you can expect to see hypotension, JVD, and muffled heart sounds, also known as the Beck triad. If, on e-FAST, you can see abnormal fluid within the pericardial sac, your diagnosis is confirmed. Pericardiocentesis or pericardial window should be performed to drain the pericardial space.

Our last life-threatening condition is thoracic vertebral fracture. This occurs after high impact mechanisms of injury. Exam will typically reveal bony step-offs and tenderness on palpation of the spine, with associated motor or sensory deficits. On chest x-ray, you can see a fracture of the thoracic vertebrae. Make sure to immobilize the spine in these patients at all times until definitive treatment is provided.

Here’s a clinical pearl! If the patient is stable, the diagnosis of a thoracic vertebral fracture should be confirmed with dedicated spine x-rays or CT.

Now that unstable patients are taken care of, let’s talk about stable patients. Unlike immediately life-threatening conditions that are typically recognized during the primary survey, injuries in a stable patient might not be as obvious. So, your next step is to perform a thorough secondary survey and obtain adjunctive tests, such as a full set of trauma labs including type and screen, ABG, CBC, CMP, lactate, urinalysis, pregnancy test, and urine tox screen. Additionally, diagnostic tests such as chest x-ray, e-FAST, and CT chest can help narrow down your differential.