A 74-year-old man is brought to the emergency department after being involved in a major motor vehicle collision. According to the report from paramedics, he was a restrained passenger. The patient has superficial injuries to the lower extremities and blunt chest trauma. He has pain "all over" but is answering all questions appropriately. Initial blood pressure is 98/65 mm Hg, pulse is 105/min, and respirations are 18/min. Oxygen saturation is 100% on 40% oxygen via face mask. Examination shows some bruises over the anterior chest, clear lungs, and no murmurs or abnormal heart sounds. The abdomen is soft and nontender. Which of the following is the most appropriate next step in evaluation of this patient?
A)Bedside ultrasound examination
B)Cardiac biomarkers
C)CT scan of the chest with intravenous contrast
D)Noncontrast CT scan of the head
E)Posteroanterior and lateral chest x-rays

Question

A 74-year-old man is brought to the emergency department after being involved in a major motor vehicle collision.  According to the report from paramedics, he was a restrained passenger.  The patient has superficial injuries to the lower extremities and blunt chest trauma.  He has pain "all over" but is answering all questions appropriately.  Initial blood pressure is 98/65 mm Hg, pulse is 105/min, and respirations are 18/min.  Oxygen saturation is 100% on 40% oxygen via face mask.  Examination shows some bruises over the anterior chest, clear lungs, and no murmurs or abnormal heart sounds.  The abdomen is soft and nontender.  Which of the following is the most appropriate next step in evaluation of this patient?
A)Bedside ultrasound examination
B)Cardiac biomarkers
C)CT scan of the chest with intravenous contrast
D)Noncontrast CT scan of the head
E)Posteroanterior and lateral chest x-rays

Quizplus · Accepted Answer

Explanation: Motor vehicle collisions are the most common cause of blunt thoracic trauma leading to cardiac and pulmonary injury. Blunt cardiac injury can manifest as cardiac contusion leading to depressed cardiac contractility and acute heart failure; cardiac arrhythmias; or myocardial rupture leading to pericardial effusion, tamponade, and cardiogenic shock. Less commonly, valve injury or coronary artery dissection can occur, resulting in heart failure or myocardial infarction, respectively. The diagnostic priority in patients with blunt thoracic trauma and early signs of shock (eg, hypotension, tachycardia) is identification of injuries that can be rapidly fatal (eg, pneumothorax, aortic dissection, hemoperitoneum, pericardial effusion leading to tamponade), which is best accomplished with bedside ultrasound or focused assessment with sonography in trauma (FAST). Detection of abnormalities should prompt further directed evaluation (eg, CT scan, echocardiography) or specific therapy (eg, laparotomy, pericardiocentesis). (Choice B) Cardiac biomarkers (eg, troponin I) are often elevated in patients with blunt thoracic trauma. However, the elevated levels are nonspecific, and routine measurement is not recommended unless there is high suspicion for myocardial infarction. (Choices C and E) Chest x-rays are always indicated, and CT scan of the chest is often indicated, in patients with blunt thoracic trauma. However, bedside (ie, anteroposterior) chest x-rays are typically performed as obtaining posteroanterior and lateral chest x-rays requires patients to stand; in addition, these tests are typically preceded by FAST to quickly assess for rapidly fatal injuries. (Choice D) A noncontrast CT scan of the head should be obtained in patients with head trauma or abnormal neurologic findings suspicious for stroke. It is not indicated in this patient with injuries confined to the thorax and the lower extremities. Educational objective: Patients with blunt thoracic trauma should have an initial screening with bedside ultrasound or focused assessment with sonography in trauma to assess for injuries that can be rapidly fatal (eg, pneumothorax, aortic dissection, hemoperitoneum, pericardial effusion leading to tamponade). References: AIUM practice guideline for the performance of the focused assessment with sonography for trauma (FAST) examination. (http://www.ncbi.nlm.nih.gov/pubmed/25336497)

A 74-Year-Old Man Is Brought to the Emergency Department After