USMLE Step 2 Quiz
Practice Initial Trauma Assessment And Management in USMLE Step 2 with focused quiz questions that help you check what you know, review explanations, and build confidence with test-style prompts.
Question 1 / 20
0 of 20 answered
A 24-year-old man is brought in after a stab wound to the left parasternal area. He is hypotensive with a blood pressure of 88/60 mmHg, tachycardic at 125/min, and has muffled heart sounds on auscultation. His jugular veins are distended. A bedside ultrasound (FAST exam) reveals a large pericardial effusion.
Which of the following is the most likely diagnosis?
This quiz focuses on Initial Trauma Assessment And Management, giving you a quick way to practice the rules, question types, and explanations that matter most for USMLE Step 2.
Try each quiz question before looking at the correct answer. Use the explanations to review missed ideas, then come back to similar questions until the pattern feels familiar.
A 24-year-old man is brought in after a stab wound to the left parasternal area. He is hypotensive with a blood pressure of 88/60 mmHg, tachycardic at 125/min, and has muffled heart sounds on auscultation. His jugular veins are distended. A bedside ultrasound (FAST exam) reveals a large pericardial effusion.
Which of the following is the most likely diagnosis?
Explanation: The patient's presentation with Beck's triad (hypotension, jugular venous distention, and muffled heart sounds) in the setting of penetrating chest trauma is highly suggestive of cardiac tamponade. The FAST exam confirms a pericardial effusion. This constitutes obstructive shock, where fluid in the pericardial sac restricts diastolic filling of the heart, leading to decreased cardiac output. This is a life-threatening injury that must be identified and managed during the primary survey.
A 45-year-old man is the restrained driver in a high-speed motor vehicle collision. He is hemodynamically stable with a blood pressure of 130/80 mmHg and a heart rate of 90/min. He complains of abdominal pain, and on examination, there is tenderness in the left upper quadrant with a positive seatbelt sign.
Which of the following is the most appropriate next step in evaluating for intra-abdominal injury?
Explanation: For a hemodynamically stable patient with suspected blunt abdominal trauma, a CT scan of the abdomen and pelvis with IV contrast is the diagnostic modality of choice. It provides detailed anatomical information, can identify solid organ injury (e.g., splenic or liver laceration), retroperitoneal hematoma, and active extravasation of contrast, which would not be well visualized on a FAST exam. The FAST exam is primarily used for hemodynamically unstable patients to rapidly identify hemoperitoneum. Diagnostic peritoneal lavage is invasive and has been largely supplanted by FAST and CT.
A 30-year-old man is brought to the trauma bay after a severe assault. His blood pressure is 80/40 mmHg and heart rate is 135/min. He has diffuse abdominal tenderness. After an initial crystalloid bolus, his blood pressure remains 85/45 mmHg.
What is the most appropriate next step to guide management?
Explanation: In a hemodynamically unstable patient with blunt abdominal trauma, the immediate goal is to determine if the source of shock is intra-abdominal hemorrhage. The FAST exam is the ideal test in this scenario because it is rapid, non-invasive, and can be performed at the bedside without delaying resuscitation. A positive FAST exam (showing free fluid) in this unstable patient would be an indication for immediate exploratory laparotomy. A CT scan is contraindicated as it requires transporting an unstable patient away from the resuscitation area. While proceeding directly to laparotomy is the ultimate destination if the FAST is positive, the FAST exam is the diagnostic step to confirm the need for surgery.
A 19-year-old male is brought to the emergency department after sustaining a gunshot wound to the epigastrium. On examination, he is diaphoretic and pale. His blood pressure is 90/50 mmHg and his heart rate is 120/min. His abdomen is rigid and diffusely tender.
What is the most appropriate next step in management?
Explanation: Penetrating abdominal trauma with hemodynamic instability or signs of peritonitis (e.g., rigidity, diffuse tenderness) is a clear indication for immediate exploratory laparotomy. Further diagnostic imaging like a CT scan or FAST exam is unnecessary and would delay life-saving surgical intervention to control hemorrhage and intra-abdominal contamination. While fluid resuscitation should be initiated, the definitive management is surgical.
During a fight, a 28-year-old man is stabbed in the right chest. He is now in respiratory distress. On examination, there is a 3-cm wound on his right lateral chest wall, and a bubbling sound is heard with each inspiration. His oxygen saturation is 90% on room air.
What is the most appropriate immediate management of this patient's chest wound?
Explanation: This patient has an open pneumothorax, also known as a "sucking chest wound." The defect in the chest wall allows air to enter the pleural space during inspiration, collapsing the lung and impairing ventilation. The immediate treatment is to cover the wound with an occlusive dressing and tape it on only three sides. This creates a one-way valve that allows air to exit the pleural space during expiration but prevents it from entering during inspiration. Suturing the wound shut could convert it into a life-threatening tension pneumothorax. A chest tube should be placed, but at a separate site, not through the traumatic wound.
A 55-year-old man is brought to the emergency department after a motor vehicle collision in which his chest struck the steering wheel. He is in significant respiratory distress. Physical examination reveals paradoxical motion of a segment of his left anterior chest wall. His oxygen saturation is 89% on a non-rebreather mask. A portable chest X-ray confirms multiple rib fractures.
The patient's hypoxemia is primarily due to which of the following?
Explanation: The patient has a flail chest, defined by fractures of three or more consecutive ribs in two or more places. While pain and the paradoxical chest wall motion contribute to respiratory failure, the most significant cause of hypoxemia in patients with flail chest is the underlying pulmonary contusion. The bruised lung parenchyma becomes edematous and filled with blood, leading to significant ventilation/perfusion (V/Q) mismatch and shunting, which impairs gas exchange.
A 25-year-old female is the front-seat passenger in a low-speed motor vehicle collision. She is brought to the emergency department in a cervical collar. She is alert, oriented, and not intoxicated. She denies neck pain or tenderness. On examination, there is no midline posterior cervical tenderness, and she has no neurologic deficits. She has a minor abrasion on her right forearm.
What is the most appropriate management of her cervical spine?
Explanation: This patient meets all five of the NEXUS (National Emergency X-Radiography Utilization Study) low-risk criteria for ruling out a clinically significant cervical spine injury. The criteria are: no posterior midline cervical spine tenderness, no evidence of intoxication, a normal level of alertness, no focal neurologic deficit, and no painful distracting injuries. Since she meets these criteria, her cervical spine can be safely cleared based on the clinical examination, and imaging is not required. The cervical collar can be removed.
A 30-year-old man suffers a gunshot wound to the left flank. He is awake and alert but anxious. His blood pressure is 95/65 mmHg and heart rate is 115/min. He is being taken to the operating room for an exploratory laparotomy.
During the brief period before surgical control of bleeding is achieved, what is the most appropriate target for fluid resuscitation?
Explanation: In patients with penetrating torso trauma and ongoing hemorrhage, the strategy of permissive hypotension (or hypotensive resuscitation) is recommended until definitive surgical control of bleeding is achieved. The goal is to maintain a systolic blood pressure (SBP) of 80-90 mmHg. This pressure is sufficient to maintain perfusion to vital organs (brain, heart) but low enough to avoid dislodging newly formed clots and exacerbating hemorrhage. Aggressively restoring normal blood pressure before the bleeding is stopped can lead to worse outcomes. This strategy does not apply to patients with traumatic brain injury.
A 40-year-old man is rescued from a burning building. He is awake and talking but has a hoarse voice. Examination reveals soot in his nares and mouth, and singed eyebrows. His initial oxygen saturation is 98% on room air, and his lungs are clear to auscultation. He is not in any respiratory distress.
Which of the following is the most appropriate next step in this patient's management?
Explanation: This patient has multiple signs of significant inhalational injury (soot, singed hairs, hoarseness). Hoarseness is a particularly concerning sign of laryngeal edema. Although he is currently stable, airway edema can progress rapidly and unpredictably, leading to complete airway obstruction. The standard of care is to secure the airway with early, elective endotracheal intubation before the edema makes it difficult or impossible. Waiting for the development of respiratory distress is dangerous and can lead to a crisis situation.
A trauma patient arrives after a high-speed car crash. The primary survey is complete, and he has been fully exposed for the secondary survey. The ambient temperature in the trauma bay is 20°C (68°F). The patient begins to shiver.
Which of the following is the most important immediate action to address this finding?
Explanation: The "E" in the primary survey (ABCDE) stands for Exposure and Environment, which includes preventing hypothermia. Trauma patients are at high risk for heat loss. Shivering is a physiological response to cold and a sign of developing hypothermia. Hypothermia is a component of the "lethal triad" of trauma (acidosis, hypothermia, coagulopathy) and must be prevented. The most important immediate action is to apply active rewarming measures, such as covering the patient with warm blankets. Using warmed IV fluids and increasing the room temperature are also important. Checking a temperature is necessary, but the intervention should not be delayed. Administering paralyzing agents would stop the shivering but worsen the hypothermia.
A 72-year-old woman taking warfarin falls at home. She is hemodynamically stable in the emergency department but complains of severe right-sided flank and back pain. Her abdomen is soft and non-tender. A FAST exam is negative for intraperitoneal fluid. Her initial hematocrit is 40%, but a repeat level 2 hours later is 34%.
Which of the following is the most appropriate imaging study to identify the source of bleeding?
Explanation: This patient is stable but has evidence of ongoing hemorrhage (falling hematocrit) and is at high risk due to her age and anticoagulation use. Her symptoms of flank/back pain and the negative FAST exam suggest a retroperitoneal source of bleeding, which is not well-visualized by ultrasound. The most appropriate imaging study for a hemodynamically stable patient with suspected retroperitoneal hemorrhage is a CT scan of the abdomen and pelvis with IV contrast. This will accurately identify a retroperitoneal hematoma and can show active contrast extravasation.
A 33-year-old man presents to the trauma bay after a motor vehicle accident. His blood pressure is 88/52 mmHg, heart rate is 128/min, and respiratory rate is 24/min. He has received 2 liters of crystalloid en route with minimal response. He has bilateral femur fractures. You initiate a massive transfusion protocol.
Which of the following complications is most likely to be exacerbated by large-volume resuscitation with packed red blood cells and crystalloids if not actively prevented?
Explanation: Trauma patients are at high risk for hypothermia due to environmental exposure, shock, and resuscitation with room-temperature or refrigerated fluids and blood products. Hypothermia is a critical component of the 'lethal triad' of trauma (acidosis, hypothermia, coagulopathy). It impairs platelet function and the enzymatic activity of the coagulation cascade, worsening hemorrhage. Active measures such as using fluid warmers and warm blankets are essential to prevent this complication during resuscitation. Hypocalcemia (due to citrate in blood products), metabolic acidosis (from shock and saline), and hyperkalemia (from stored PRBCs) can occur, but hypothermia is a universal and major risk.
A 70-year-old woman is brought to the emergency department after being struck by a car. She is obtunded. Her blood pressure is 85/50 mmHg and heart rate is 130/min. Physical examination reveals an unstable pelvis. Two large-bore intravenous lines are established.
In addition to initiating fluid resuscitation, which of the following is the most appropriate initial step to manage her hemodynamic instability?
Explanation: This patient has hemorrhagic shock likely due to a pelvic fracture. An unstable pelvis can lead to massive hemorrhage from the presacral venous plexus and bony fragments. The most important initial step to control this hemorrhage is to stabilize the pelvis by applying a pelvic binder or sheet. This reduces the volume of the pelvic cavity, tamponades the venous bleeding, and stabilizes the fracture. While angiography may be needed later for arterial bleeding and surgical fixation is the definitive treatment, the pelvic binder is a critical, immediate life-saving maneuver in the primary survey.
A 22-year-old man sustains blunt chest trauma from striking the steering wheel in a car accident. He is hemodynamically stable. An ECG obtained on arrival shows sinus tachycardia and a new right bundle branch block.
Which of the following is the most appropriate next step to evaluate for a suspected cardiac injury?
Explanation: The presence of a new conduction abnormality (right bundle branch block) on an ECG after significant blunt chest trauma is highly concerning for blunt cardiac injury. The most appropriate next diagnostic step is a transthoracic echocardiogram. An echocardiogram can directly visualize cardiac structures and assess for wall motion abnormalities (indicative of myocardial contusion), valvular injury, septal rupture, or pericardial effusion. While the patient should be admitted for monitoring and troponins may be checked, the echocardiogram is the key diagnostic study to define the extent of the injury.
A 25-year-old woman is involved in a severe car crash and presents with a deformed femur and signs of shock. Her blood pressure is 70/40 mmHg and her heart rate is 145/min. Two large-bore IVs have been placed.
Which of the following is the most appropriate initial fluid for resuscitation in this patient?
Explanation: This patient is in Class IV hemorrhagic shock. Modern trauma resuscitation protocols emphasize early, balanced resuscitation with blood products over large-volume crystalloid infusion. A massive transfusion protocol, using packed red blood cells, fresh frozen plasma, and platelets in a 1:1:1 ratio, more closely mimics whole blood and helps prevent the dilutional coagulopathy, acidosis, and hypothermia associated with aggressive crystalloid resuscitation. Therefore, initiating a balanced blood product transfusion is the most appropriate initial fluid management.
A 40-year-old male is brought to the emergency department after a fall from a ladder. He is intubated due to a GCS of 7. His blood pressure is 150/90 mmHg and heart rate is 65/min. On neurologic examination, his right pupil is 6 mm and nonreactive, while his left pupil is 3 mm and reactive. He withdraws his left extremities to a painful stimulus but has no motor response on the right.
These clinical findings are most consistent with which of the following life-threatening injuries?
Explanation: The patient's signs of a unilaterally dilated, nonreactive pupil ('blown pupil') and contralateral hemiparesis constitute a classic presentation of uncal herniation. This occurs when increased intracranial pressure, often from an epidural or subdural hematoma, forces the uncus of the temporal lobe over the tentorium cerebelli. This compresses the ipsilateral oculomotor nerve (CN III), causing pupillary dilation, and the ipsilateral cerebral peduncle, which contains the corticospinal tracts, causing contralateral motor deficits. This is a neurosurgical emergency.
A 32-year-old woman sustains a gunshot wound to the left chest. On arrival, she is in shock. A large-bore chest tube is placed in the left pleural space and immediately returns 1,800 mL of blood. Her vital signs remain unstable despite ongoing resuscitation.
What is the most appropriate next step in management?
Explanation: This patient has a massive hemothorax, which is an indication for emergent thoracotomy. The definitions for massive hemothorax include an initial chest tube output greater than 1,500 mL of blood, or continued bleeding at a rate of more than 200 mL/hour for 2-4 hours. Given the immediate return of 1,800 mL and persistent instability, surgical exploration is required to control the source of the hemorrhage, which is likely from a major vessel such as an intercostal artery or the pulmonary hilum. All other options would delay definitive, life-saving treatment.
An 18-year-old male arrives after a motorcycle crash. He is tachycardic and hypotensive. His airway is patent and he is breathing spontaneously. On secondary survey, his left thigh is markedly swollen, tense, and deformed. Distal pulses are present.
After initiating fluid resuscitation, which of the following interventions is most critical for managing his hemorrhagic shock?
Explanation: The patient's shock is most likely due to hemorrhage from a mid-shaft femur fracture, which can result in 1-1.5 liters of blood loss into the thigh. Applying a traction splint is a critical intervention. It realigns the bone fragments, reduces pain, and most importantly, decreases the potential space within the thigh compartment, which helps tamponade the bleeding from the bone ends and surrounding soft tissues. This is a key step in source control for hemorrhage. Fasciotomy is for compartment syndrome, not primarily for hemorrhage control. Tranexamic acid is an important adjunct, but mechanical control of bleeding is the priority.
A 35-year-old construction worker falls from a height of 20 feet. In the emergency department, he is in severe respiratory distress. His blood pressure is 80/50 mmHg, heart rate is 140/min, and respiratory rate is 36/min. On physical examination, his trachea is deviated to the left. There are absent breath sounds over the right hemithorax, which is hyperresonant to percussion. The jugular veins are distended.
Which of the following is the most appropriate immediate intervention?
Explanation: The patient's presentation of hypotension, tachycardia, jugular venous distention, tracheal deviation, and unilateral absent breath sounds with hyperresonance is classic for a tension pneumothorax. This is a life-threatening emergency caused by air trapping in the pleural space, leading to mediastinal shift and obstructive shock. The most appropriate immediate intervention is needle decompression to convert the tension pneumothorax to a simple pneumothorax, followed by chest tube placement. Waiting for a chest X-ray would cause a fatal delay. Endotracheal intubation and positive pressure ventilation before decompression can worsen the tension physiology. Chest tube insertion is the definitive treatment but is performed after immediate needle decompression.
A 28-year-old man is brought to the emergency department after being involved in a motorcycle collision. He is agitated and moaning incoherently. His airway is patent, but he has gurgling respirations. He has significant mid-face trauma with obvious deformity. His respiratory rate is 28/min with bilateral breath sounds. His blood pressure is 105/70 mmHg and heart rate is 120/min.
What is the most appropriate next step in the management of this patient's airway?
Explanation: This patient has a compromised airway (gurgling) with altered mental status and severe mid-face trauma. The significant facial trauma makes both nasotracheal intubation (risk of cribriform plate fracture and intracranial placement) and orotracheal intubation (distorted anatomy, difficulty with mask ventilation) highly risky or contraindicated. Given the gurgling respirations suggesting blood or secretions in the airway and the anatomical distortion from facial trauma, a surgical cricothyroidotomy provides the most reliable definitive airway management. An oropharyngeal airway alone is inadequate for definitive airway protection in this compromised patient.