In a patient presenting with blunt trauma and obvious head involvement, a CT angiography of the head is obtained based on the Denver Modification Screening Criteria for blunt cerebrovascular injury (BCVI). The patient is subsequently diagnosed with a Grade 3 injury.
Which of the following below correctly describes a Grade 3 BCVI according to the widely accepted Biffl scale?
Correct Answer: D
The Biffl scale, first described in 1999, has been used to describe the spectrum of vascular injuries seen on angiography following blunt trauma to the head and neck. This scale provides prognostic information based on the injury grade in addition to helping guide monitoring and therapeutic strategies. The table below provides descriptive information on the grading scale, as well as the corresponding risk of stroke associated with the involved vessel.
BCI, Blunt carotid artery injury; BVI, Blunt vertebral artery injury.
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A 30-year-old male with no significant medical history is brought to the emergency department via EMS after sustaining a fall from an estimated 20 feet onto the pavement below. On arrival to the ED, he is alert and oriented with stable vital signs. The portable chest X-ray obtained in the trauma bay is concerning for a widened mediastinum. He is taken to the CT scanner for further evaluation of his injuries.
All of the following statements regarding blunt thoracic aortic injury (BTAI) are true EXCEPT:
Correct Answer: B
An estimated 1.5% to 2% of all patients sustaining blunt thoracic trauma have a blunt aortic injury (BAI). The main risk factor for this type of injury is a mechanism that involves a rapid deceleration event, with the most common cause being involvement in a motor vehicle collision (Answer A). The majority of blunt thoracic aortic injuries occur at the aortic isthmus, or just distal to the left subclavian. Although multiple theories exist to explain this phenomenon, anatomically this area represents the transition from the mobile ascending aorta to the fixed descending aorta, thereby predisposing it to injury in rapid deceleration events (Answer C). Diagnosis begins with a high clinical suspicion, followed by initial evaluation involving plain film of the chest in the trauma bay. A normal plain film in the trauma bay does not exclude the presence of a BTAI (Answer D). The imaging modality of choice is contrast-enhanced CT angiography of the chest. The NEXUS criteria was developed as a guideline to help determine which patients, based on mechanism and presentation, warranted further evaluation with CT of the chest for further evaluation for BAI. Subsequent modifications have been made, with the most recent guidelines, when used in the appropriate clinical context, serving to reduce the need for unnecessary imaging studies. While TEE can be used to evaluate the thoracic aorta, it requires the patient to be intubated, is typically less available in the acute setting in the trauma bay, and is not interchangeable with TTE (Answer B). On diagnosis, initial management of a BAI in a hemodynamically stable patient involves obtained adequate vascular access and maintaining adequate heart rate (<100 bpm) and blood pressure control (<100 mm Hg), typically with a beta blocker if not contraindicated (Answer E). Hemodynamically unstable trauma patients require an emergent trip to the operating room.
Blunt aortic injuries in hemodynamically stable patients can be classified based on radiographic appearance.
Which of the following terms is not used in the classification of blunt thoracic aortic injuries?
The evaluation of BTAI following trauma is best done by obtaining a CT of the chest with intravenous contrast. Findings on imaging can then be used to classify individual BTAIs as Grade 1 to 4 in severity, which is then used in the management algorithm including both serial imaging studies and invasive intervention either by endovascular or open techniques. According to the widely accepted grading scale, Grade 1 is an intimal tear, Grade 2 is an intramural hematoma, Grade 3 is a pseudoaneurysm, and Grade 4 is a free rupture (Answer A, B, C, and E). By definition, a pseudoaneurysm, also known as a false aneurysm, where intraluminal blood dissects into the walls of the vessel, thereby creating an area that is only contained by the arterial adventitia or surrounding tissues. Pseudoaneurysm formation commonly occurs following trauma but can also occur in the setting of other pathological processes including vasculitis and other inflammatory processes. In contrast, a true aneurysm is a local dilation of an artery that involves all three layers (intima, media, and adventitia) of the arterial wall. True aneurysm formation is not seen in the setting of BTAIs.
Reference:
A 31-year-old male presents to the emergency department following a mountain biking accident. He has an obvious deformity to his right thigh, which appears to be an expanding hematoma. Aside from some otherwise superficial abrasions, he has no other significant trauma burden. He is taken to the operating room that day for Orthopedic surgery and undergoes an uneventful procedure. The following day, on postoperative day 1, the physician is called to his room where the patient is noted to have altered mental status and dyspnea with associated hypoxemia. On closer inspection, he is noted to have a fine petechial rash covering his neck and anterior trunk.
All of the following statements about the underlying diagnosis are true EXCEPT:
Fat embolism syndrome (FES) is a rare clinical syndrome that classically presents with the triad of neurological changes, respiratory distress (dyspnea, tachypnea, hypoxemia), and a nondependent petechial rash (Answer C). Interestingly, although part of the classic triad, the petechial rash is only present in an estimated 33% of patients. Although reports exist of FES occurring following nonorthopedic trauma (eg Isolated soft tissue injury), nonorthopedic operations (eg Liposuction, lipo-injection), and nontrauma-related conditions (eg Pancreatitis), the majority of cases present in 24 to 72 hours following long bone and pelvic fracture injuries (Answer A, B). A diagnosis of FES is typically a diagnosis of exclusion that is made in the appropriate clinical setting. Although laboratory evaluation and imaging (CT head and chest) should be obtained to rule out other diagnoses in the differential for altered mental status and respiratory distress, none of these tests can individually confirm the diagnosis of FES (Answer D). Once a diagnosis is made, treatment is largely supportive, including fluid resuscitation, oxygenation, and mechanical ventilation if indicated (Answer E).
A young appearing male with an unknown past medical history is transported to the emergency department by EMS after being involved in a motor vehicle accident in which he was the unrestrained driver. The patient required a prolonged extrication from his vehicle, which was severely damaged, and EMS noted that the steering wheel was grossly deformed. The patient was intubated at the scene and vital signs on admission included the following:
In addition to a complete evaluation given the extent of his trauma, what additional testing would be the most helpful initially in ruling out a blunt cardiac injury (BCI)?
The true incidence of BCI in high impact trauma is unknown but is most commonly seen following motor vehicle collisions. BCI sustained during high-impact trauma can present in a variety of ways ranging from new arrhythmias to devastating structural injuries. Interestingly, the majority of BCIs are silent on presentation, with patients asymptomatic at the time of presentation. Given the wide variety of presentations and manifestations of BCI, there is no clear diagnostic criteria. Therefore, the appropriate diagnostic evaluation begins with a high degree of clinical suspicion. Evaluation should begin with a baseline ECG and cardiac biomarkers. The role of cardiac biomarkers alone is still a topic of much debate, but when used in conjunction with ECG, they may play an important role in ruling out BCI (Answer B, C). Alone, a negative ECG has a reported negative predictive value of up to 95%, which is increased to 100% with the addition of negative biomarker testing. Continued cardiac monitoring, specifically in the setting of new ECG findings, is recommended. For patients with new ECG findings or hemodynamic instability on presentation, an echocardiogram is recommended for further structural and functional evaluation (Answer E). Of the answers above, Answer D represents a thorough initial evaluation for BCI in a patient who is hemodynamically stable on presentation. There is no indication at present to obtain an echocardiogram (Answer A).