A 40-year-old male is admitted to the Surgical Intensive Care Unit (SICU) following a high-speed motor vehicle collision with an extensive trauma burden. He has no significant past medical history, and on arrival to the SICU he is noted to be hemodynamically stable. However, his respirations are shallow and he is currently requiring 4 L nasal cannula to maintain an oxygen saturation above 92%. On review of his imaging, you note multiple right-sided rib fractures including ribs 2 to 8 with fractures of ribs 3 to 6 in two places.
Which of the following statements is true regarding the diagnosis and management flail chest?
Correct Answer: D
Radiographically, a flail segment is defined as fractures of three or more ribs in two or more places. This can be seen on plain film imaging or more commonly on cross-sectional CT. Clinically, a diagnosis of flail chest is made when a patient has the radiographic findings consistent with the diagnosis, as well as a clinically apparent chest wall segment with paradoxical movement (Answer A). During normal inspiration, the chest wall expands while the diaphragm contracts, causing a strong negative pressure force within the pleural cavity. When a flail segment is present, this negative pressure causes a paradoxical movement of the segment inward, rather than outward with the remainder of the chest wall. This has many implications on underling pulmonary physiology, including hypoventilation, worsening atelectasis, and increased work of breathing, all of which contribute to respiratory failure (Answer B). The majority of patients presenting with rib fractures and flail chest are treated nonoperatively with pain control, aggressive pulmonary toilet, and ventilator support as indicated. No prospective randomized-controlled trials exist comparing surgical rib fixation to standard pain control with multimodal analgesia, including epidural catheter placement. Currently there is no hard set of indications for surgical rib fixation, and the clear majority of patients are management nonoperatively with multimodal analgesia and aggressive pulmonary toilet (Answer C). Flail chest is more commonly seen with blunt trauma compared to penetrating trauma. Owing to the pliability of the pediatric chest wall, rib fractures in the setting of blunt thoracic trauma are much more uncommon compared to the adult population (Answer E).
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A 50-year-old male with a past medical history of hypertension and long-standing tobacco use is being admitted to the SICU after being involved in a motorcycle accident resulting in multiple bilateral rib fractures with underlying pulmonary contusions. On arrival to the ICU the patient is noted to be in obvious discomfort, taking in shallow breaths and requiring 4 L nasal cannula for oxygen supplementation.
All of the following statements about the management of a polytrauma with pulmonary contusions are true EXCEPT:
Correct Answer: A
Pulmonary contusions result from blunt thoracic trauma, which may or may not be associated with overlying rib fractures, particularly in children (Answer E). Pulmonary contusions can develop over the first 24 to 48 hours, even if they are not seen on the initial trauma radiograph (Answer B). The pathophysiology involves direct impact injury to the lung parenchyma, resulting in leakage of blood and plasma into the alveoli. This results in decreased compliance and impaired diffusion. (Answer D). Initial management involves adequate resuscitation with either an isotonic crystalloid solution or colloid solution to maintain adequate tissue perfusion, initiation of multimodal pain management, and aggressive pulmonary toilet (Answer C). Although no studies have ever shown the benefit of colloid over crystalloid in the initial trauma resuscitation phase, there is evidence to support the negative effects of over-resuscitation, with any fluids, including worsening of oxygenation and development of Acute Respiratory Distress Syndrome. (Answer A).
All of the following are appropriate methods to evaluate for the presence of an acute traumatic hemothorax in the setting of blunt thoracic trauma EXCEPT:
Correct Answer: E
In the setting of acute blunt thoracic trauma, one must rule out the presence of an acute hemothorax. Typically, a plain film portable chest Xray is obtained in the trauma bay to evaluate for the presence of a hemothorax or pneumothorax that would require urgent placement of a chest tube (Answer B). More recently, ultrasound has become a widely accepted method of initial evaluation of the thoracic cavity, specifically to determine the presence of a significant pleural effusion/hemothorax or pneumothorax (Answer D). Both of these modalities provide a quick, real time assessment of the patient in the trauma bay. In stable patients, a CT of the chest can be obtained, in addition to other indicated trauma imaging, which can help further identify the presence of a hemothorax and other concomitant thoracic injuries (Answer C). In the unstable trauma patient who arrives to the trauma bay, early evaluation with tube thoracostomy may be indicated if there is concern for possible hemothorax (Answer A). Although MRI of the chest can identify the presence of a hemothorax, the test itself requires significantly more time to perform and does not provide additional necessary information in the setting of acute thoracic trauma (Answer E).
A 25-year-old male is brought to the emergency department after being involved in a multiple vehicle motor collision. On primary survey his ABCs are intact and his initial vital signs are as follows: Temp 99°F, HR 100 bpm, BP 130/70 mm Hg, RR 19, Sat 95% on room air. On completion of his trauma workup he is noted to have an extensive trauma burden, including a traumatic right sided hemo- pneumothorax with associated overlying rib fractures for which a tube thoracostomy is performed.
Which of the following statements regarding acute traumatic hemothoraces and pneumothoraces is true?
Correct Answer: C
Following blunt trauma in the hemodynamically stable patient, the diagnosis of an acute hemothorax or pneumothorax can be made using portable plain chest X-ray, ultrasound, or CT of the chest. An occult pneumothorax is defined as an asymptomatic pneumothorax that is not seen on chest radiograph but is present on CT imaging. Stable patients with an occult pneumothorax may be observed without need for immediate intervention, regardless of whether or not they require positive pressure ventilation (Answer B and Answer D). Although the presence of a traumatic hemothorax should prompt consideration for tube thoracostomy placement, it is necessary to note the clinical stability of the patient and the size of the hemothorax. All traumatic hemothoraces do not necessarily require drainage with a chest tube, and not all patients requiring a tube thoracostomy require further evaluation with VATS (Answer A). In general, indications to consider operative intervention rely on patient physiology rather than any absolute numbers. In addition to patient physiology, situations prompting consideration to proceed to the operating room include persistent retained hemothorax, persistent air-leak on post-injury day 3, and >1500 mL via the chest tube in a 24-hour period (Answer E). Tracheobronchial injuries resulting from blunt thoracic trauma are rare, occurring in less than 1% of patients presenting with blunt thoracic trauma. Classically, these patients present with significant air leak on tube thoracostomy placement, as well as pneumothorax or pneumomediastinum that reaccumulates despite chest tube placement (Answer C).
A 55-year-old female is the unrestrained passenger in a rollover motor vehicle accident. Among other injuries, she sustains multiple facial fractures, fractures involving C2-4 and multiple rib fractures bilaterally. According to the Denver Criteria, which of the following is NOT an indication for Computed Tomography Angiography (CT Angiography or CTA) as part of the comprehensive trauma evaluation?
The Denver Criteria for screening for BCVI in the setting of trauma is a set of criteria (see below) that was created to guide clinicians on the need for obtaining further imaging, specifically CT angiography, when there is concern for a BCVI. Mechanisms of injury that lead to BCVI most commonly involve cervical hyperextension, flexion, and rotation, as well as direct injury to the boney structures involving the vascular foramen. Approximately 1% of hospitalized blunt trauma patients in the United States have a BCVI, but unfortunately the majority are diagnosed when they become symptomatic. Therefore, a push was made to screen asymptomatic patients who sustained a significant blunt trauma. Several studies by Biffl et al. and Cothren et al. aided in creating screening criteria for evaluation of the trauma patient at risk for BCVI.
Table below shows the Denver Modification of Screening Criteria for BCVI (Answers B-E). While many of these injuries are sustained during a high impact trauma, the mechanism of the blunt trauma itself is not an indication for further imaging to rule out BCVI (Answer A).
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