Cardiac and Great Vessel Injuries: Tamponade, Blunt Cardiac Injury, Commotio Cordis, and Aortic Disruption Practice Questions

25 multiple-choice questions on Cardiac and great vessel injuries: tamponade, blunt cardiac injury, commotio cordis, and aortic disruption for paramedic and EMT students, from Chapter 36 (Chest Trauma). Read each question, pick your answer, then tap Show answer to check it and read the explanation.

25 practice questions

1. Pericardial tamponade is:

   1. A. Blood in the pleural space that compresses the lung
   2. B. Air in the mediastinum that compresses the trachea
   3. C. Fluid in the pericardial sac that restricts filling
   4. D. Bruising of the myocardium that weakens contraction
   Show answer

   Answer: C. Fluid in the pericardial sac that restricts filling

   Blood in the tight pericardial sac raises pressure around the heart so the ventricles cannot fill, and cardiac output falls. Bruising of the myocardium is blunt cardiac injury, which weakens the pump rather than restricting filling.

2. A patient stabbed near the sternum is hypotensive. In the field, all three findings of Beck triad are:

   1. A. Present in nearly every case
   2. B. Easy to hear in a moving unit
   3. C. Needed before you suspect it
   4. D. Often absent or hard to find
   Show answer

   Answer: D. Often absent or hard to find

   Muffled heart tones are hard to hear in the field, and neck veins may be flat if the patient is also bleeding, so the full triad is found in only a minority of tamponade cases. A penetrating wound in the cardiac box with hypotension should raise suspicion of tamponade without waiting for the classic triad.

3. A patient with suspected traumatic pericardial tamponade is hypotensive, and transport to surgery will take 15 minutes. A fluid bolus may help temporarily because it:

   1. A. Drains the blood from around the heart
   2. B. Raises filling pressure in the heart
   3. C. Lowers the pressure in the pericardium
   4. D. Slows the heart to allow more filling
   Show answer

   Answer: B. Raises filling pressure in the heart

   In tamponade, the pericardial blood squeezes the heart and limits filling. Raising venous pressure with a modest fluid bolus can push more blood into the ventricles and support cardiac output until the tamponade is relieved surgically. Fluid does not drain or lower pericardial pressure, and slowing the heart is harmful.

4. Electrical alternans, seen with large pericardial effusions, appears on the ECG as:

   1. A. ST elevation in leads II, III, and aVF
   2. B. A widened QRS from a right bundle branch block
   3. C. QRS amplitude that varies from beat to beat
   4. D. Peaked T waves across the precordial leads
   Show answer

   Answer: C. QRS amplitude that varies from beat to beat

   The heart swings within a fluid-filled sac, so the electrical axis and QRS height alternate between beats. ST elevation in the inferior leads suggests an inferior MI, not an effusion.

5. A 24-year-old was stabbed just left of the sternum at the 4th intercostal space. His BP is 76/58 mmHg, his heart rate is 128 beats/min, his neck veins are distended, breath sounds are equal, and heart tones are faint. The most likely injury is:

   1. A. Tension pneumothorax
   2. B. Massive hemothorax
   3. C. Aortic disruption
   4. D. Cardiac tamponade
   Show answer

   Answer: D. Cardiac tamponade

   A wound over the heart with JVD, a narrow pulse pressure, muffled tones, and equal breath sounds fits tamponade. Tension pneumothorax also causes JVD and shock, but breath sounds would be absent on one side.

6. A 24-year-old with a stab wound over the heart has JVD, muffled heart tones, and a BP of 76/58 mmHg. The most important prehospital management is:

   1. A. Rapid transport and fluid for preload
   2. B. Needle decompression of the left chest
   3. C. A diuretic to lower venous pressure
   4. D. Nitroglycerin to reduce the afterload
   Show answer

   Answer: A. Rapid transport and fluid for preload

   The heart is preload dependent in tamponade, so a fluid bolus may support output while the patient is rushed to surgery; pericardiocentesis is done in the field only where protocols allow. Diuretics and nitrates lower preload and can cause arrest.

7. A small volume of blood can cause acute tamponade because the pericardium:

   1. A. Is thin and tears with small volumes
   2. B. Cannot stretch quickly to hold extra fluid
   3. C. Normally holds about 500 mL of fluid
   4. D. Stretches easily, but the heart muscle is stiff
   Show answer

   Answer: B. Cannot stretch quickly to hold extra fluid

   The fibrous pericardium is tough and inelastic, so a sudden small increase in volume causes a steep rise in pressure. Slow effusions allow it to stretch over time, which is why medical effusions can be large without tamponade. The sac normally holds a few tablespoons of fluid, not hundreds of milliliters, and it is the sac, not the heart muscle, that resists acute stretch.

8. A patient with suspected blunt cardiac injury is most likely to show:

   1. A. Bradycardia with peaked T waves and short PR
   2. B. Delta waves with a short PR interval
   3. C. Tachycardia and premature ventricular beats
   4. D. A prolonged QT from low magnesium levels
   Show answer

   Answer: C. Tachycardia and premature ventricular beats

   Bruised myocardium is irritable, producing sinus tachycardia, PVCs, and other dysrhythmias, so continuous monitoring is needed. Delta waves with a short PR interval are a feature of Wolff-Parkinson-White syndrome, not trauma.

9. In blunt cardiac injury, the chamber most often injured is the:

   1. A. Right ventricle
   2. B. Left ventricle
   3. C. Left atrium
   4. D. Right atrium
   Show answer

   Answer: A. Right ventricle

   The right ventricle sits directly behind the sternum, so it takes the brunt of an anterior blow. The left ventricle is more posterior and lateral and is injured less often.

10. A 50-year-old struck the steering wheel and has sternal bruising, an irregular pulse, and a BP of 102/70 mmHg. Breath sounds are equal and the neck veins are flat. The priority is:

    1. A. Needle decompression of the left chest
    2. B. Continuous ECG monitoring and a 12-lead
    3. C. Aspirin 324 mg chewed to treat ischemia
    4. D. Pericardiocentesis before you transport
    Show answer

    Answer: B. Continuous ECG monitoring and a 12-lead

    An irregular pulse after a sternal blow suggests blunt cardiac injury, so the rhythm must be monitored and documented. Aspirin is not given for traumatic chest pain because it can worsen bleeding.

11. Commotio cordis occurs when:

    1. A. A blow tears the aorta at its isthmus
    2. B. A blow drives the sternum into the heart
    3. C. A blow bruises the right ventricle wall
    4. D. A blow during repolarization triggers VF
    Show answer

    Answer: D. A blow during repolarization triggers VF

    A relatively minor impact timed to the vulnerable upstroke of the T wave can trigger ventricular fibrillation in a structurally normal heart. Bruising of the ventricle is blunt cardiac injury, which needs much more force.

12. A 14-year-old is struck in the chest by a baseball and collapses. He is pulseless and apneic. Your first priority is to:

    1. A. Needle decompress both sides of the chest
    2. B. Give a fluid bolus for traumatic arrest
    3. C. Restrict spinal motion before starting CPR
    4. D. Begin CPR and apply an AED immediately
    Show answer

    Answer: D. Begin CPR and apply an AED immediately

    Commotio cordis causes VF, and survival depends on immediate CPR and early defibrillation. Bilateral decompression and fluids address traumatic arrest from tension or blood loss, which a single blow from a baseball does not cause.

13. A patient with a suspected blunt aortic injury arrives at the trauma center. The classic chest radiograph finding that supports this diagnosis is a:

    1. A. Deep sulcus sign
    2. B. Gas bubble under the diaphragm
    3. C. Widened mediastinum
    4. D. Bowel loop in the left chest
    Show answer

    Answer: C. Widened mediastinum

    Blood from a contained aortic tear collects around the aorta in the mediastinum and widens it on the chest film (often with loss of the aortic knob contour or deviation of the trachea or NG tube to the right); CT angiography confirms it. A deep sulcus sign is a lucent costophrenic angle on a supine film, a sign of pneumothorax. Gas under the diaphragm means a perforated hollow organ in the abdomen. A bowel loop in the chest indicates diaphragmatic rupture. Knowing this helps explain why a normal-looking patient after a high-speed deceleration still needs a trauma center. (ATLS 10th ed., Ch. 4.)

14. The mechanism most typical of traumatic aortic disruption is:

    1. A. Sudden high-speed deceleration
    2. B. A low-velocity penetrating stab
    3. C. Slow crushing compression of the chest
    4. D. A low-energy blow to the sternum
    Show answer

    Answer: A. Sudden high-speed deceleration

    High-speed frontal or side-impact crashes and falls from height create shearing forces on the aorta. A low-energy sternal blow can cause commotio cordis, but not aortic tearing.

15. Of patients with traumatic aortic disruption, about how many die at the scene?

    1. A. 10% to 20%
    2. B. 80% to 90%
    3. C. 30% to 40%
    4. D. 50% to 60%
    Show answer

    Answer: B. 80% to 90%

    Most complete tears cause rapid exsanguination, and only patients whose tear is contained by the adventitia reach the hospital alive. For those survivors, avoiding hypertension and getting fast surgery prevents a contained tear from rupturing.

16. A 35-year-old woman in a 60-mph frontal crash reports tearing pain between her shoulder blades. Her arm BP is 168/94 mmHg, but her femoral pulses are weak. The most likely injury is:

    1. A. Traumatic aortic disruption
    2. B. Pericardial tamponade
    3. C. Blunt cardiac injury
    4. D. Tension pneumothorax on the left
    Show answer

    Answer: A. Traumatic aortic disruption

    Interscapular pain with upper-body hypertension and weak lower pulses (pseudocoarctation) after deceleration suggests an aortic tear. Tamponade causes hypotension, not hypertension in the arms.

17. After a 60-mph frontal crash, a 35-year-old has tearing pain between her shoulder blades, an arm BP of 168/94 mmHg, and weak femoral pulses. The fluid strategy is to:

    1. A. Give 2 L rapidly to protect the kidneys
    2. B. Avoid fluids that raise her BP further
    3. C. Give fluids to keep SBP above 140 mmHg
    4. D. Give epinephrine to support the aorta
    Show answer

    Answer: B. Avoid fluids that raise her BP further

    These findings suggest a contained traumatic aortic tear (interscapular pain, upper-body hypertension, weak lower pulses). Any rise in pressure or shear stress can rupture the thin remaining wall, so fluids are limited to keeping a vein open, pain is treated, and she goes to a trauma center where the BP and heart rate are actively lowered. A rapid 2-L bolus raises the pressure on the tear and offers no kidney benefit in a hypertensive patient. Keeping the SBP above 140 mmHg is the opposite of the goal; hospital targets are an SBP of about 100 to 120 mmHg or lower. Epinephrine raises BP and heart rate, increasing the stress on the injured aorta. (ATLS 10th ed.; EAST guideline.)

18. Neck veins that distend further during inspiration, seen in some cases of tamponade, are called:

    1. A. Kussmaul respirations
    2. B. Grey Turner sign
    3. C. Kussmaul sign
    4. D. Battle sign
    Show answer

    Answer: C. Kussmaul sign

    Kussmaul sign is a paradoxical rise in jugular pressure on inspiration because the right heart cannot accept more venous return. Kussmaul respirations are the deep, rapid breathing of metabolic acidosis, which shares only the name.

19. A knife is impaled in the left chest of a patient with signs of tamponade. You should:

    1. A. Remove the knife to relieve the tamponade
    2. B. Remove the knife and seal the wound
    3. C. Pull the knife partly out to stop bleeding
    4. D. Stabilize the knife and transport rapidly
    Show answer

    Answer: D. Stabilize the knife and transport rapidly

    An impaled object may be plugging a hole in the heart, so it is stabilized in place for removal in the operating room. Removing it can cause sudden massive bleeding and worsen the tamponade.

20. A penetrating wound in the cardiac box should raise suspicion of heart injury. This area extends:

    1. A. Between the nipples, clavicles to costal margin
    2. B. Across the upper abdomen below the umbilicus
    3. C. Between the scapulae on the posterior thorax
    4. D. Along the lateral chest at the midaxillary line
    Show answer

    Answer: A. Between the nipples, clavicles to costal margin

    The cardiac box is the anterior area between the nipple lines from the clavicles to the costal margins. Wounds outside it can still reach the heart, but those inside it carry the highest risk.

21. In commotio cordis, examination of the heart typically shows:

    1. A. A ruptured right ventricle wall
    2. B. No structural injury to the heart
    3. C. A large pericardial effusion
    4. D. A tear at the aortic isthmus
    Show answer

    Answer: B. No structural injury to the heart

    Commotio cordis is an electrical event, so the heart is structurally normal and responds to prompt defibrillation. A ruptured ventricle results from far greater force and is usually fatal at the scene.

22. Your protocol allows pericardiocentesis, and a 30-year-old with a stab wound and signs of tamponade has just lost his pulse. The needle is usually inserted:

    1. A. Subxiphoid, angled toward the right hip
    2. B. At the right 2nd intercostal space, straight in
    3. C. At the left 7th intercostal space
    4. D. Subxiphoid, angled toward the left shoulder
    Show answer

    Answer: D. Subxiphoid, angled toward the left shoulder

    The subxiphoid approach, between the xiphoid and the left costal margin and angled toward the left shoulder, reaches the pericardial sac while avoiding the lungs and coronary arteries. Angling toward the right hip aims away from the heart into the liver. The right 2nd intercostal space is not a pericardial approach (the 2nd space is used for needle decompression of the pleural space). The left 7th intercostal space has no role and risks the lung, heart, and spleen. Pericardiocentesis is not in the NHTSA National EMS Scope of Practice for paramedics, so it is done in the field only where a local protocol specifically allows it; otherwise the treatment is rapid transport for surgery.

23. After a steering wheel impact, a driver has blunt cardiac injury. The most common dysrhythmia in these patients is:

    1. A. Third-degree heart block
    2. B. Atrial flutter with block
    3. C. Sinus tachycardia
    4. D. Ventricular fibrillation
    Show answer

    Answer: C. Sinus tachycardia

    Sinus tachycardia is the most common rhythm after blunt cardiac injury, followed by premature beats (PVCs, PACs) and new atrial fibrillation or bundle branch block. Heart block, flutter, and VF occur but are less common. Any new dysrhythmia after a chest impact should be monitored and reported.

24. Commotio cordis most often affects:

    1. A. Adults whose chests hit a steering wheel
    2. B. Young athletes struck by a ball or puck
    3. C. Adults with prior heart disease
    4. D. Workers crushed under heavy objects
    Show answer

    Answer: B. Young athletes struck by a ball or puck

    Children and young adults, whose chest walls are compliant, are at risk when a baseball, hockey puck, or fist strikes the precordium. Commotio cordis typically occurs in structurally normal hearts, steering wheel impacts in adults cause blunt cardiac injury, and crushing injuries are high-energy mechanisms that cause structural damage rather than commotio cordis.

25. Traumatic pericardial tamponade is most often caused by:

    1. A. Fractures of the lower left ribs
    2. B. Blunt steering wheel impacts
    3. C. Aortic tears at the isthmus
    4. D. Penetrating wounds to the heart
    Show answer

    Answer: D. Penetrating wounds to the heart

    Stab and gunshot wounds lacerate the heart, and the pericardium seals the hole so blood collects around it. Blunt trauma such as a steering wheel impact can also cause tamponade, but much less often than penetrating injury, and the aortic isthmus lies outside the pericardium, so a tear there bleeds into the mediastinum and left chest.