Breaking the Cage

I got a pain in my chest, and I can’t breathe.

George Lopez

It’s a hot summer Saturday night, your friends are enjoying their life and you’re the resident on-call, as many times in your life…

It’s almost 2 am when the triage nurse calls you because in 15 minutes the prehospital ambulance will bring a trauma patient:

A – 22 yo male;
T – 45 minutes before, arriving in 15 minutes;
M – Car against a tree at high speed, major damages to the car, the patient driver alone in the car with seatbelts on, and airbags explosion, extraction time 30 minutes;
I – Confused with a low level of consciousness, alcohol smell, thoracic trauma for the steering wheel, abdominal pain, lower leg fracture;
S – 100/80 mmHg, 99 bpm, RF 28/min, Sat from 89% in room air to 94% with O₂ support;
T – O₂ mask, collar, spinal board, 1 IV line, 500 mL of ringer lactate.

If you’re new to our website, we suggest you review these previous posts:

• Preparedness;
• ATLS.

You assemble the trauma team and, as the resident on-call, you’ll be on the patient, an anesthetist resident will be at the head and your 2 consultants will play as team leaders/support. Each of you has a dedicated nurse.

Here the patient comes, the team leaders hear the prehospital information while you start the primary evaluation:

• A – free, no vomit or blood in the mouth, trachea in line, pt responds to verbal stimuli, O₂ mask with FiO₂ 50%;
• B – uneven thoracic movements, decreased breath sounds on the right side, dullness at percussion, Sat 91% with O₂ support.

As you know, you cannot proceed to C until B is solved, right? So, what would you do?

As we can imagine, thoracic injuries are extremely common. Think that about 33% of them will need to be hospitalized, moreover blunt thoracic injuries are responsible for 20-25% of all traumatic deaths.

The lesions we may find in the chest will impair oxygenation/ventilation and blood flow, and they may cause infection/sepsis. Thus, some lesions must be found during the primary survey, others must be encountered during the secondary survey, and few may wait until the tertiary survey.

Primary survey – the 6 lesions with life-threatening consequences:

• Airway obstruction
• Tracheobronchial tree injury
• Tension pneumothorax
• Open pneumothorax
• Massive hemothorax
• Cardiac tamponade

Secondary survey – the potentially lethal lesions:

• Simple pneumothorax
• Hemothorax
• Flail chest
• Pulmonary contusions
• Cardiac contusion
• Traumatic aortic hematoma
• Diaphragmatic lesion
• Esophageal injury

Let’s review them!

Airway Obstruction

It results from swelling, bleeding, or vomiting. These materials are aspirated into the airway, interfering with gas exchange. Several injury mechanisms can produce this type of problem. Search for air hunger, like intercostal and supraclavicular muscle retractions, foreign body obstruction, stridor, or changes in the patient’s voice. Airway obstruction should be treated with clearance of the blood or vomitus from the airway by suctioning. Usually, a definitive airway is necessary, and you should prepare for a very difficult one!

Tracheobronchial Tree Injury

Usually correlated to deceleration trauma or penetrating mechanism. The most common site of the lesion is close to the carina. ​​Patients typically present with hemoptysis, cervical subcutaneous emphysema, tension pneumothorax, and/or cyanosis. Primary treatment will be managing the upper airway or the lower depending on the clinical findings, meaning intubation or selective intubation associated with one or two intercostal drains to solve the associated pneumothorax. 

Remember that if the tracheal injury comes from a penetrating mechanism and the intubation cannot bridge the hole, there is always the option to tube the patient through the hole created by the injury itself (use a boogie to find the distal trachea and then use a small tube with the Seldinger’s technique to canulate it) – we know it sounds crazy but we saw it and did in person! After that, the pt must go to the OR to repair the defect. 

Pneumothorax

It can be simple, open, tensive, or occult. 

Causes of a simple PNX in blunt trauma are:

• Sudden increase of intrathoracic pressure with alveoli rupture;
• Rib fractures lacerating the lung;
• Deceleration with a tear of the lung;
• Blunt force crushing the alveoli.

When we speak about a PNX we should find subcutaneous air with decreased breath sounds on the affected side. 

The tension PNX is when the air collection pressure exceeds the atmospheric one, creating a contralateral shift of the mediastinum (pressure on the vena cava with reduction of the cardiac preload). You have to make it “open” as soon as possible. The best technique to convert a closed PNX into an open one is the finger thoracostomy (fourth-fifth intercostal space on the midaxillary line). The needle decompression technique (second intercostal space on the midclavicular line) may be used if a scalpel is not readily available, but remember that it fails most times because of the cannula kinking.

The chest x-ray (CXR) has a sensitivity of 52% with a specificity of 100% to detect a PNX. The eFAST 92% of Sens and 99% of Spec. Obviously, the CT has the highest sens/spec ratio.

The treatment of a pneumothorax seen on a CXR is drainage with an intercostal drain; however, in some cases, it can be safely observed. 

The open PNX, meaning there is an opening hole in the thorax, must be treated with a chest drain and closure of the injury (with a 3 sided dressing or surgical closure, depending on the setting).

Sometimes you may find a PNX on a CT scan that wasn’t seen on the CXR during the primary survey (AKA Occult Pneumothorax – OPNX). In this case, you may not drain the PNX, but you should put the patient on high-flow oxygen regardless of the patient’s oxygen saturation (to help reabsorb the pneumothorax) and follow it up with a CXR after 6 hours. It is debated if you should drain the PNX in the case the patient needs to be put on positive-pressure ventilation.

When you decide to observe an OPNX around 6% will increase, needing a chest tube. Of those patients with OPNX requiring positive pressure ventilation, 14% will fail the conservative management, needing a chest tube.

When you insert intercostal drainage, the patient must be covered with good painkillers and he/she must start respiratory physiotherapy as soon as possible!

Hemothorax

Blood in the pleural cavity may come from a lacerated lung, rib fractures, thoracic vascular injuries, abdominal bleeding with a hole in the diaphragm. On a CXR you’ll be able to see collections of 200-300 mL or more, it is useful to diagnose a massive hemothorax (white lung on CXR). 

Ultrasound lets you see small hemothorax (from 20 mL), it has a Sens of 98% and a Spec of 100%. The treatment is, in almost all the cases (hemothorax more than 300 mL), a chest tube (consider the same supportive treatment as for the PNX). If it is massive (more than 1500 mL, or output higher than 200 mL/h for more than 2-4 h) the patient needs to be evaluated in the OR. 

Cardiac Tamponade

The pericardial sac has only a bit of space to be filled until the heart has no more space to move and stops. It is quite rare in blunt trauma; however, on the other side, a penetrating trauma in the “heart box” should raise the alarm in the team (the pericardial box is the space between the two midclavicular lines, anteriorly and posteriorly)!

The diagnosis may be clinical, but most of the time the US makes the diagnosis sure (FAST is 90–95% accurate in identifying the presence of pericardial fluid). The treatment is to open the pericardial sac and free the heart, this can be done by a sternotomy (stable pt) or an anterolateral left thoracotomy (unstable pt). Those maneuvers should be done only if a trained surgeon is present. If this cannot be achieved a pericardiocentesis may be taken into account as a bridge maneuver.

Flail Chest

We speak of a flail chest when three or more continuous ribs are fractured in two or more places, creating a discontinuity in the chest wall. Paradoxical chest movements are created from negative intrapleural pressure during inspiration with paradoxical air movement. This condition is always associated with a lung injury, and this is the main issue. Treatment is pain control, possible CPAP, or intubation needed (if the patient cannot cope alone). Operative ribs fixation is very rarely needed, but very effective when used. Remember you need to treat the patient’s oxygenation problem (the large pulmonary contusion the patient has underneath), not the CXR image!

Pulmonary Contusion

It is extremely frequent and it has a mortality of 25%. The issue is the radiological diagnosis that comes after 4-24 h from the trauma, so you need to suspect it from the mechanism of injury!

The pathophysiology is based on the poor gas exchange (with an altered V/Q matching), leading to increased pulmonary vascular resistance, decreased lung compliance, and inflammatory reaction. 

Symptoms are dyspnea, tachypnea, rhonchi, wheezers, hypoxemia (low oxygen saturation develops before CXR findings), and/or hypercarbia. 

When minor, it spontaneously resolves in 5-10 days. Be strict with the fluids (they will increase the pulmonary edema), start chest physiotherapy ASAP, set a good pain control, and give supplementary oxygen. 

Blunt Cardiac Injury

We are speaking of myocardial muscle contusion, cardiac chamber rupture, coronary artery dissection and/or thrombosis, and valvular disruption. Usually, they are consequences of blunt thoracic injuries from motor vehicle crashes, followed by pedestrians struck by vehicles, motorcycle crashes, and falls from heights. The suspect comes from the mechanism of the trauma and the presence of alterations at the EKG (multiple premature ventricular contractions, unexplained sinus tachycardia, atrial fibrillation, bundle-branch block, and ST-segment changes). Patients with a blunt injury to the heart diagnosed by conduction abnormalities (an abnormal EKG) are at risk for sudden dysrhythmias and should be monitored for the first 24 hours. After this interval, the risk of dysrhythmia appears to decrease substantially. 

Remember that a cardiac dysrhythmia may be the cause of the trauma (and not caused by it), don’t underestimate this point!

Traumatic Aortic Hematoma

Remember this key point, a patient with a ruptured aorta won’t survive for more than a bunch of seconds… This means that the majority of the patients will die directly at the scene. If a patient arrives alive at the hospital, it means the rupture is “closed” by a hematoma and, probably, is not actively bleeding. This is not the reason for the patient’s instability, search for something different. If the hematoma starts bleeding, the patient will die before you can even take the scalpel to open up his chest!

Now, the suspect must be risen by the mechanism of trauma (e.g. deceleration) and the CXR findings, and the diagnosis should be confirmed by CT scan. The definitive treatment is stenting in an angiography suite. In the meantime, the patient’s heart rate and hypertension should be controlled with short-acting drugs (i.e. b-blockers, calcium channel blockers, nitrates) to reduce the risk of bleeding.

Diaphragmatic Injury

It is quite common when the penetrating injury is on the thoracoabdominal area. Sometimes a high-energy blunt trauma may cause it. The suspect may be risen by the CXR due to the presence of the stomach gas bubble or small bowel inside the thorax. Usually seen on the left side due to the absence of the liver that on the right side separates the diaphragmatic defect from the viscera below. If the herniated content is massive, it can impair lung expansion, causing respiratory distress. The repair is surgical and it can be achieved with a simple suture (open or laparoscopically), or using a mesh, depending on the timing of the repair and the width of the defect. 

Esophageal Injury

Most commonly from penetrating injuries. The clinical picture of patients with blunt esophageal rupture is identical to that of post-emetic esophageal rupture. The diagnosis must be confirmed by endoscopy or contrast radiographic exams. The treatment is still not clear. Usually, it is a direct repair through thoracotomy or thoracoscopy, or using endoscopic stents (no high level of experience, only isolated cases!). 

Rib Fractures

This is the commonest thoracic injury. When you see more than 3 rib fractures the probability of an associated solid organ injury is very high (as a marker of major energy transfer). Pay attention to the elderly, where even low energy may create major damages. 

Treatment is good pain control and early respiratory physiotherapy, otherwise, the pulmonary contusion underneath will become pneumonia!

Sternal Fractures

Usually due to direct sternal impact directed to the upper and mid sternum. In 50-60% of cases, there are associated injuries (e.g. myocardial contusion, needing a proper workup (baseline EKG, continue monitoring for 24 hs, Troponin dosage), and/or pulmonary contusions). Treatment is conservative as per rib fractures, but occasionally a surgical fixation (ORIF) may be needed.

Sternoclavicular Joint Fracture/Dislocation

This is a rare but potentially fatal injury because of injuries to the lungs, the main airway (direct injury or compression), the major vessels, the brachial plexus, the esophagus, and so on…

Usually, the mechanism is trauma at the base of the neck presenting with stridor or changes in the voice. Treatment is a close reduction or surgical fixation (ORIF).

Clavicle Fractures

They commonly occur as isolated fractures. Displaced fractures may injure vessels, lungs, or brachial plexus. Usually, the trauma is a lateral force to the shoulder. The 80% of fractures are in the middle third. The treatment is represented by immobilization with a sling or figure-of-8 bandage. Occasionally surgical fixation may be needed for displaced fractures.

Scapula Fractures

Usually occurs for direct impact with high energy. In 80% of cases, they are associated with other injuries (50% are in the spine or the thorax/abdomen). It should be studied with an x-ray or CT scan and will need aggressive pain management and immobilization. They are signs of transfer of high energy, therefore search for associated injuries!

Retained Hemothorax

It is persistent hemothorax after drainage. When a patient has a retained hemothorax, the risk of infection with empyema and/or pneumonia is high.

The more time the hemothorax remains in place, the more difficult will be to solve it because of the fibrotic changes that will develop. The treatment of a retained hemothorax may be as simple as inserting a second drain, or as complex as performing a decortication through thoracotomy.

Remember that the best therapy is prevention.

Now that we have a clearer idea, we can get back to our patient… We left ourselves on the B evaluation/treatment…

• B – Our suspicion is a combined hemopneumothorax. Therefore, we go for an intercostal drain, obtaining a gush of air and 500 mL of blood from the drain;
• C – BP 90/50 mmHg, 110 bpm, abdomen painful with seatbelt signs, painful pelvis on compression, deformed left fibula with an open fracture with no active bleeding. A second IV line is inserted, the massive transfusion protocol activated, and a pelvic binder positioned;
• eFAST – No pericardial effusion, no residual pneumothorax on the right, regular sliding on the left thorax, free fluid on the right abdomen and in the pelvis.

You talk to the trauma team leaders and decide to go straight to the theatre (unstable patient with positive abdominal fast). 

So… This is it!

Just a brief overview… We will explore more in detail the different kinds of injuries in due time…

In the meantime… See you next time!

Namasté…

References

1. ESTES Webinar 14 – Management of Thoracic Injuries
2. Brasel KJ, et al. Treatment of occult pneumothoraces from blunt trauma. The Journal of Trauma 1999;46:987-90.
3. Moore FO, et al. Blunt traumatic occult pneumothorax: is observation safe?–results of a prospective, AAST multicenter study. The Journal of Trauma 2011;70:1019-23.
4. Prakash PS, et al. Predictors of retained hemothorax in trauma: Results of an Eastern Association for the Surgery of Trauma multi-institutional trial. J Trauma Acute Care Surg 2020;89:679-85.
5. Boffard KD. Manual of Definitive Surgical Trauma Care. 5^th Ed. Boca Raton, FL: CRC Press; 2019.
6. Advanced Trauma Life Support: Student Course Manual. 10^th Ed. Chicago, IL: American College of Surgeons; 2018.
7. DuBose J, et al. Management of post-traumatic retained hemothorax: a prospective, observational, multicenter AAST study. J Trauma Acute Care Surg 2012;72:11-22.

How to Cite This Post

Marrano E, Bellio G. Breaking the Cage. Surgical Pizza. Published on February 5, 2022. Accessed on October 1, 2024. Available at [https://surgicalpizza.org/trauma/breaking-the-cage/].