Hemothorax and Massive Hemothorax Practice Questions

25 multiple-choice questions on Hemothorax and massive hemothorax 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. A stab wound just to the right of the sternum causes rapid shock and dullness on that side. A likely bleeding source at this location is the:

   1. A. Internal mammary artery
   2. B. Descending thoracic aorta
   3. C. Splenic artery
   4. D. Left subclavian vein
   Show answer

   Answer: A. Internal mammary artery

   The internal mammary (internal thoracic) arteries run just lateral to each edge of the sternum, and injury can cause a rapid massive hemothorax. The descending aorta lies left of the spine at the back of the chest, the splenic artery is in the left upper abdomen, and the left subclavian vein is on the other side under the clavicle.

2. A massive hemothorax is generally defined as an accumulation of:

   1. A. 250 mL or more of blood
   2. B. 500 mL or more of blood
   3. C. 1,500 mL or more of blood
   4. D. 4,000 mL or more of blood
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   Answer: C. 1,500 mL or more of blood

   About 1,500 mL in one hemithorax, or ongoing rapid bleeding, defines a massive hemothorax and represents roughly a third of adult blood volume. Smaller collections of a few hundred milliliters may cause few signs.

3. A 20-kg child struck by a car has dullness at the left base and a heart rate of 170 beats/min. If about 400 mL of blood has collected in her chest, she has lost roughly:

   1. A. 5% of her blood volume
   2. B. 25% of her blood volume
   3. C. 10% of her blood volume
   4. D. 60% of her blood volume
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   Answer: B. 25% of her blood volume

   A child's blood volume is about 80 mL/kg, so a 20-kg child has about 1,600 mL; 400 mL is about 25%, a class II to III loss that explains her tachycardia. Children keep a near-normal BP until late, so the heart rate is the warning sign. 10% comes from using an adult blood volume of about 5 L, which underestimates the loss. 5% underestimates it even further. 60% would mean a loss of nearly 1,000 mL, far more than 400 mL. (PALS 2020; PHTLS 10th ed., pediatric trauma.)

4. The bleeding in most hemothoraces comes from the:

   1. A. Coronary arteries and cardiac veins
   2. B. Esophageal and gastric varices
   3. C. Liver, through the diaphragm
   4. D. Lung tissue and intercostal vessels
   Show answer

   Answer: D. Lung tissue and intercostal vessels

   Lacerated lung and torn intercostal or internal mammary vessels are the usual sources, often from rib fractures or penetrating wounds. The lung bleeds at low pressure and often slows, while arterial chest wall bleeding can be brisk.

5. A 35-year-old stabbed in the right lateral chest has a BP of 78/50 mmHg and a heart rate of 132 beats/min. Breath sounds are absent on the right, the right chest is dull to percussion, the neck veins are flat, and the trachea is midline. The most likely injury is:

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

   Answer: D. Massive hemothorax

   Shock with absent breath sounds, dullness, and flat neck veins points to blood loss into the chest. A tension pneumothorax would be hyperresonant with distended neck veins.

6. In a massive hemothorax, the neck veins are usually flat because:

   1. A. The trachea compresses the jugular veins
   2. B. Blood loss has depleted venous volume
   3. C. Air in the pleura pushes blood downward
   4. D. The heart is pumping more forcefully
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   Answer: B. Blood loss has depleted venous volume

   The patient has lost so much blood into the chest that there is not enough volume to distend the veins. Tension pneumothorax raises venous pressure, which is why JVD helps tell the two apart.

7. Prehospital management of a massive hemothorax focuses on:

   1. A. Oxygen, rapid transport, and cautious fluids
   2. B. Needle decompression to drain the blood
   3. C. Fluid boluses to restore a normal BP
   4. D. Pericardiocentesis to relieve the chest pressure
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   Answer: A. Oxygen, rapid transport, and cautious fluids

   The bleeding needs surgical control, so the field priorities are oxygenation, ventilatory support, and getting the patient to a trauma center with only enough fluid to maintain perfusion. A needle cannot drain clotting blood from the chest.

8. A 30-year-old stabbed in the right chest has a suspected massive hemothorax and no head injury. After 250 mL of fluid, his BP is 86/58 mmHg, he has a radial pulse, and he is alert. The best fluid plan now is to:

   1. A. Run fluid wide open until his BP is normal
   2. B. Give 2 L more to prevent a delayed drop in BP
   3. C. Hold further fluid unless his perfusion falls
   4. D. Start a vasopressor to bring his SBP to 120 mmHg
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   Answer: C. Hold further fluid unless his perfusion falls

   With an SBP in the 80s, a radial pulse, and normal mentation, he already meets the permissive hypotension target for penetrating trauma without head injury (SBP about 80 to 90 mmHg), so more fluid is held and given in small boluses only if perfusion worsens, with blood products preferred where carried. Running fluid wide open to a normal BP raises pressure on fresh clots and dilutes clotting factors, increasing bleeding into the chest. Giving 2 L in advance has the same harms and adds hypothermia. Vasopressors do not replace lost volume and are not used to reach a normal SBP in hemorrhagic shock. Targets vary by protocol. (PHTLS 10th ed.; ATLS 10th ed.)

9. A massive hemothorax causes hypoxia and shock by:

   1. A. Air entering the pleural space each breath
   2. B. Pericardial compression of the right atrium
   3. C. Lung compression combined with blood loss
   4. D. Bronchospasm from blood in the airway
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   Answer: C. Lung compression combined with blood loss

   The blood collapses the lung on that side and the volume loss causes hypovolemic shock, so oxygen delivery fails twice over. Air entering the chest with each breath describes an open pneumothorax.

10. A patient who has both air and blood in the same pleural space has a:

    1. A. Pneumomediastinum
    2. B. Hemopericardium
    3. C. Pneumopericardium
    4. D. Hemopneumothorax
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    Answer: D. Hemopneumothorax

    Hemopneumothorax is common in chest trauma because the same injury tears the lung and its vessels. Hemopericardium is blood in the pericardial sac, a different compartment.

11. In a supine patient, blood in the pleural space collects mainly:

    1. A. Anteriorly, just beneath the sternum
    2. B. Posteriorly, along the back of the chest
    3. C. At the apex, above the clavicle
    4. D. Evenly around the whole surface of the lung
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    Answer: B. Posteriorly, along the back of the chest

    Blood is heavy and settles in the dependent posterior chest, so diminished sounds and dullness are found at the bases and back. Air does the opposite and rises anteriorly.

12. A patient with the findings of a massive hemothorax is hypotensive. Needle decompression of that side would be expected to:

    1. A. Not help, since blood is the problem
    2. B. Drain the blood and restore the BP
    3. C. Re-expand the lung by venting air
    4. D. Convert it to a simple hemothorax
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    Answer: A. Not help, since blood is the problem

    Needle decompression vents air, but it cannot drain enough blood to matter and does not stop the bleeding. If air and blood are both present, decompression may help only the air component.

13. Aggressive IV fluid in a patient with a massive hemothorax can:

    1. A. Cause a tension pneumothorax to form
    2. B. Dislodge clots and dilute clotting factors
    3. C. Make the hemothorax clot more quickly
    4. D. Shift blood out of the chest into the legs
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    Answer: B. Dislodge clots and dilute clotting factors

    Raising the BP to normal can pop off fragile clots, and crystalloid dilutes platelets and clotting factors, both increasing bleeding. Fluid does not affect air in the pleural space, so it does not cause tension.

14. Keeping a patient with a massive hemothorax warm matters because hypothermia:

    1. A. Impairs clotting and worsens bleeding
    2. B. Speeds clotting and causes emboli
    3. C. Re-expands the collapsed lung
    4. D. Constricts vessels and stops bleeding
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    Answer: A. Impairs clotting and worsens bleeding

    Hypothermia, acidosis, and coagulopathy reinforce each other in the trauma triad of death. Cold slows clotting enzymes, so it worsens bleeding rather than stopping it.

15. A patient with rib fractures was stable at the scene. During a long transport, he becomes tachycardic and develops new dullness and diminished sounds at the base of the injured side. The most likely cause is:

    1. A. A developing tension pneumothorax
    2. B. A resolving pulmonary contusion
    3. C. A developing hemothorax
    4. D. A delayed sternal fracture
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    Answer: C. A developing hemothorax

    Dullness at the dependent base with rising heart rate suggests blood collecting in the pleural space. A tension pneumothorax would produce hyperresonance and JVD, not dullness.

16. A patient with a suspected massive hemothorax should be transported to:

    1. A. A burn center with a surgical ICU
    2. B. A stroke center with a CT scanner
    3. C. A community hospital without surgeons
    4. D. A trauma center with thoracic surgery
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    Answer: D. A trauma center with thoracic surgery

    Massive hemothorax often requires a chest tube, blood products, and thoracotomy, which only a trauma center can provide quickly. Burn and stroke centers are not organized around emergency thoracic surgery and massive transfusion, and a hospital without surgeons adds a delay for transfer.

17. Definitive treatment of a massive hemothorax at the hospital is:

    1. A. Needle decompression at the 2nd ICS
    2. B. Tube thoracostomy, often with surgery
    3. C. Pericardiocentesis with a long needle
    4. D. Occlusive dressing and bed rest
    Show answer

    Answer: B. Tube thoracostomy, often with surgery

    A chest tube drains the blood and measures the ongoing loss, and large or continuing output leads to thoracotomy. Pericardiocentesis treats tamponade, not blood in the pleural space.

18. A 70-kg man has a 1,500-mL hemothorax. He has lost about what fraction of his blood volume?

    1. A. About 30%
    2. B. About 10%
    3. C. About 50%
    4. D. About 75%
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    Answer: A. About 30%

    At about 70 mL/kg, his blood volume is near 4,900 mL, so 1,500 mL is roughly 30%, enough to cause hypotension. 10% would be a loss the body usually compensates for without obvious signs.

19. Which findings are shared by a massive hemothorax and a tension pneumothorax?

    1. A. Hyperresonance and distended neck veins
    2. B. Dullness to percussion and flat neck veins
    3. C. Diminished breath sounds and hypotension
    4. D. Tracheal shift toward the injury and bradycardia
    Show answer

    Answer: C. Diminished breath sounds and hypotension

    Both cause unilateral loss of breath sounds and shock, so percussion and neck veins are what separate them. Hyperresonance and JVD point to tension, while dullness and flat veins point to hemothorax. When the trachea shifts in either condition it moves away from the injured side, and both cause tachycardia, not bradycardia, until very late.

20. After needle decompression of a hemopneumothorax, the rush of air relieves the tension, but the BP stays at 76/48 mmHg and the base remains dull. The most likely explanation is:

    1. A. Recurrence from a kinked or clotted catheter
    2. B. A catheter placed into the lung tissue
    3. C. An expected effect of decompression
    4. D. Ongoing bleeding into the pleural space
    Show answer

    Answer: D. Ongoing bleeding into the pleural space

    Relief of tension without improvement in BP, plus persistent dullness, means blood loss is still driving the shock. A kinked catheter would bring back tension signs such as JVD, not dullness with flat veins.

21. For a patient with a massive hemothorax who is breathing adequately, oxygen should be titrated to an SpO2 of at least:

    1. A. 94%
    2. B. 88%
    3. C. 85%
    4. D. 75%
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    Answer: A. 94%

    Trauma patients with blood loss need high oxygen saturation because their oxygen-carrying capacity is already reduced. 88% is the target for some COPD patients and is too low for hemorrhagic shock.

22. For a patient with a suspected massive hemothorax, vascular access should be:

    1. A. One small-gauge IV at the scene
    2. B. A central line before you leave the scene
    3. C. Deferred until hospital arrival
    4. D. Two large-bore IV lines en route
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    Answer: D. Two large-bore IV lines en route

    Two large-bore lines started during transport allow fluid or blood without delaying definitive care. Spending scene time on access delays the surgery the patient needs.

23. A 30-year-old with a right hemothorax has a heart rate of 140 beats/min and a BP of 76/50 mmHg. The monitor shows sinus tachycardia. The best explanation for the rhythm is:

    1. A. A primary cardiac dysrhythmia
    2. B. Compensation for blood loss
    3. C. Commotio cordis from the impact
    4. D. Pain alone, without hypovolemia
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    Answer: B. Compensation for blood loss

    Sinus tachycardia with hypotension in a bleeding patient is the body's attempt to maintain cardiac output. Blaming pain alone ignores the hypotension and leads to under-treatment of shock.

24. An early sign of hemorrhage from a hemothorax is:

    1. A. Bradycardia with a widening pulse pressure
    2. B. Hypotension with warm, flushed, dry skin
    3. C. Tachycardia with a narrowing pulse pressure
    4. D. Hypertension with slow respirations
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    Answer: C. Tachycardia with a narrowing pulse pressure

    Early blood loss triggers vasoconstriction, raising diastolic pressure and narrowing the pulse pressure while the heart rate rises. Bradycardia with a widening pulse pressure is the Cushing response to raised intracranial pressure.

25. The most rapid, massive hemothoraces usually result from injury to the:

    1. A. Pulmonary hilum or great vessels
    2. B. Small vessels of the lung periphery
    3. C. Veins of the anterior chest wall
    4. D. Capillaries of the parietal pleura
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    Answer: A. Pulmonary hilum or great vessels

    High-pressure, high-flow vessels at the hilum and the great vessels can fill a hemithorax within minutes. Peripheral lung vessels bleed at low pressure and often stop on their own.