Pneumothorax: Overview and Practice Questions (2024)

A pneumothorax is a medical condition characterized by the presence of air in the pleural space and is a critical topic in both emergency medicine and respiratory care.

This condition, where air accumulation causes the lung to collapse, can occur spontaneously or as a result of trauma or underlying lung disease.

Understanding its pathophysiology, clinical presentation, diagnostic methods, and management strategies is essential for effective treatment and patient care.

This article explores the etiology, symptoms, diagnosis, and management practices of a pneumothorax.

What is a Pneumothorax?

A pneumothorax, or collapsed lung, occurs when air enters the pleural space between the lung and chest wall, disrupting normal lung expansion. This leads to partial or complete lung collapse, causing symptoms like chest pain and difficulty breathing. It can result from injury or spontaneously.

Signs and Symptoms

The signs and symptoms of pneumothorax may include:

• Sudden, sharp chest pain
• Shortness of breath
• Hypoxemia
• Difficulty breathing
• Tachycardia
• Tachypnea
• Chest tightness
• Fatigue
• Decreased breath sounds over the affected side
• Sudden increase in peak and plateau pressure
• Mediastinal and tracheal shift away from the affected side
• Hyperresonant percussion note over the affected lung
• Asymmetric chest movement
• Subcutaneous emphysema
• Cyanosis

Note: The signs and symptoms of a pneumothorax can vary depending on its size and the underlying cause. 

Diagnosis

Diagnosing a pneumothorax typically involves a combination of clinical assessment and imaging studies:

• Clinical Examination: A healthcare provider will begin with a physical examination, listening for reduced or absent breath sounds on the affected side and checking for signs of distress, rapid breathing, or a rapid heart rate.
• Chest X-ray: This is the most common imaging test used to diagnose pneumothorax, where air in the pleural space can be easily identified as a clear space without lung markings next to the lung edge.
• CT Scan: A computed tomography (CT) scan of the chest can provide more detailed images and is particularly useful in diagnosing small pneumothoraces or in complex cases where additional lung pathology might be present.
• Ultrasound: Increasingly used in emergency settings, chest ultrasound can be effective in detecting a pneumothorax, offering the advantages of being rapid, bedside-available, and not exposing the patient to radiation.
• Blood Gases: Although not diagnostic for pneumothorax, arterial blood gas (ABG) analyses can be used to assess the extent of impaired gas exchange.

Note: Prompt and accurate diagnosis is crucial for effective management and to prevent potential complications such as a tension pneumothorax, a life-threatening condition that requires immediate intervention.

Treatment

Treatment for a pneumothorax depends on its size and severity, along with the patient’s symptoms:

• Observation: A small, stable pneumothorax might require only monitoring and oxygen therapy, as they can resolve spontaneously.
• Needle Aspiration or Chest Tube Placement: For a larger or symptomatic pneumothorax, removing the air in the pleural space is essential. This is typically done either by needle aspiration or by inserting a chest tube to continuously evacuate the air until the lung re-expands.
• Supplemental Oxygen: Helps increase the rate of air reabsorption from the pleural space and supports better oxygenation in the body.
• Surgery: In cases of recurrent pneumothorax, severe underlying lung conditions, or non-healing pneumothorax, more invasive procedures such as video-assisted thoracoscopic surgery (VATS) or open thoracotomy might be required to repair the source of the air leak and prevent recurrence.
• Pleurodesis: A procedure to adhere the lung to the chest wall, thereby preventing future occurrences of a pneumothorax.

Prompt and accurate treatment is crucial to minimize complications and ensure the best possible outcomes.

Management decisions are typically made based on individual patient factors, including the underlying cause, overall health, and the presence of any comorbid conditions.

Pneumothorax Practice Questions

1. What is a pneumothorax characterized by?
A pneumothorax is characterized by the accumulation of air in the pleural space, the area between the lung and the chest wall, leading to partial or complete collapse of the affected lung.

2. What are the three types of pneumothorax by etiology?
Primary spontaneous, secondary spontaneous, and traumatic.

3. What causes a primary spontaneous pneumothorax?
It is idiopathic, and there is typically a development of subpleural blebs at the lung apices.

4. What can cause a secondary spontaneous pneumothorax?
Lung diseases like acute asthma, cystic fibrosis, pneumonia, sarcoidosis, pulmonary fibrosis, and lung cancer.

5. What are the two parts of the pleura, and what happens to them in a pneumothorax?
Visceral and parietal pleura, and they separate.

6. What happens to the lungs in a pneumothorax?
They collapse, which compresses the alveoli, and atelectasis ensues.

7. What may occur with a severe pneumothorax?
The great veins may become compressed, causing a diminished cardiac venous return.

8. What kind of pulmonary disorder is a pneumothorax?
Restrictive

9. What are the major pathologic or structural changes caused by a pneumothorax?
Lung collapse, atelectasis, chest wall expansion (in the case of a tension pneumothorax), compression of the great veins, and decreased cardiac venous return.

10. What causes air to enter the pleural space from the lungs?
Perforation of the visceral pleura.

11. During a pneumothorax, which way can you expect the trachea to shift?
The trachea will shift away from the affected side.

12. What occurs in the presence of an esophageal fistula or a perforated abdominal viscus, chest wall, or parietal pleura?
Air enters the pleural space from the atmosphere.

13. What is a closed pneumothorax?
Gas in the pleural space is not in direct contact with the atmosphere.

14. What is an open pneumothorax?
Pleural space is in direct contact with the atmosphere, and that gas can move freely in and out.

15. What is a tension pneumothorax?
Tension pneumothorax is a type of pneumothorax in which the intrapleural pressure exceeds the intra-alveolar pressure, creating a formation of a one-way valve leading to increased intrapleural pressure. Air enters the pleural cavity but cannot escape. Air accumulates in the pleural space with each breath and gets trapped there and is associated with the formation of a one-way valve at the point of rupture.

16. What type of pneumothorax is caused by an injury?
Traumatic

17. What pneumothorax is caused without an underlying origin?
Spontaneous

18. What pneumothorax is caused by a medical procedure?
Iatrogenic

19. What is a traumatic pneumothorax?
Penetrating or crushing wounds to the chest wall.

20. How is a penetrating wound traumatic pneumothorax classified?
Open pneumothorax

21. How is a crushing traumatic pneumothorax classified?
When a crushing chest injury occurs, the pleural space may not be in direct contact with the atmosphere, but the sharp end of a fractured rib may pierce or tear the visceral pleura. This may permit gas to leak into the pleural space from the lungs. Technically, this form of pneumothorax is classified as a closed pneumothorax.

22. What is the other name for a traumatic pneumothorax?
Sucking chest wound.

23. What happens in a tension pneumothorax?
Gas enters the pleural space during inspiration but cannot leave during expiration because the parietal pleura acts as a check valve. This condition may cause the intrapleural pressure to exceed the atmospheric pressure in the affected area.

24. Why is a tension pneumothorax serious?
This form of pneumothorax is the most serious of all since gas continues to accumulate in the intrapleural space and progressively increases the compressing pressures on the lungs and mediastinal structures of the affected area.

25. What kind of pneumothorax is secondary to pneumonia, tuberculosis, or COPD?
Spontaneous

26. What condition of a lung’s surface can cause a spontaneous pneumothorax, and in what demographic group does it often occur?
Ruptures of a small bleb or bulla on the lung surface, which may occur in tall individuals between the ages of 15 and 35 years old.

27. What is an iatrogenic pneumothorax?
A pneumothorax that occurs during specific diagnostic or therapeutic medical procedures.

28. In what situation is an iatrogenic pneumothorax always a hazard?
During positive-pressure mechanical ventilation, particularly when high tidal volumes or high system pressures are used. This is particularly common in COPD and HIV-related acute respiratory distress syndrome (ARDS).

29. What vital signs are increased when a patient has a pneumothorax?
Heart rate, cardiac output, blood pressure, and respiratory rate.

30. What chest assessment findings are present with a pneumothorax?
Hyperresonant percussion note over the pneumothorax, diminished breath sounds over the pneumothorax, tracheal shift away from the affected side, displaced heart sounds, and increased thoracic volume on the affected side.

31. What is the main determinant for how a pneumothorax is managed?
The degree of lung collapse.

32. How is a small pneumothorax managed?
The patient may need only bed rest and limited physical activity, allowing for reabsorption of intrapleural gas within 30 days.

33. How is pneumothorax larger than 20% managed?
It should be evacuated.

34. How should a less severe pneumothorax be managed?
Withdraw air via needle aspiration.

35. What is pleurodesis?
Pleurodesis is a medical procedure used to cause the lungs to adhere to the chest wall, aiming to prevent the recurrence of pneumothorax or pleural effusion. It involves the introduction of a substance (like talc or certain chemicals) into the pleural space, which creates inflammation and leads to the bonding of the pleural layers.

36. What are the parameters for a small pneumothorax?
15-20%

37. What is the parameter for a large pneumothorax?
> 20%

38. Why is oxygen therapy used to treat a pneumothorax?
It is used to treat hypoxemia, decrease the work of breathing, and decrease myocardial work.

39. When, why, and what consideration should be made when administering lung expansion therapy protocol in a pneumothorax?
With caution, lung expansion techniques are commonly administered to offset the atelectasis associated with a pneumothorax in patients with chest tubes.

40. When and why would mechanical ventilation be used to treat a pneumothorax, and what consideration should be made in its use?
Intubation and mechanical ventilation may be indicated to treat acute ventilatory failure that develops with a severe pneumothorax. A continuous form of this treatment with positive end-expiratory pressure (PEEP) may be required to maintain an adequate ventilatory status.

41. What is the most common causes of a traumatic pneumothorax?
Penetration of the sharp point of a fractured rib.

42. How does a primary spontaneous pneumothorax present?
Asymptomatic, limited chest pain, and mild breathlessness.

43. What are the clinical features of a secondary spontaneous pneumothorax?
Hypoxia, cyanosis, hypercapnia, sudden onset, severe chest pain, and dyspnea.

44. How is a pneumothorax investigated?
Chest x-ray

45. How is a small spontaneous pneumothorax managed?
Observe until it resolves spontaneously.

46. How is a larger pneumothorax managed?
Chest drain and pleurodesis.

47. What are the main types of pneumothorax?
Primary, secondary, traumatic, tension, and iatrogenic.

48. What is a primary pneumothorax?
A primary spontaneous pneumothorax occurs without preceding chest trauma or a precipitating event. It develops without a clinically apparent pulmonary disease.

49. What is a secondary pneumothorax?
It occurs as a complication of an underlying lung condition.

50. What patients are most at risk of secondary pneumothorax?
Patients with COPD, cystic fibrosis, tuberculosis, or pneumocystis jirovecii infection.

51. What are the classic x-ray features of a tension pneumothorax?
Deviation of the trachea away from the affected side, a shift of the mediastinum, and depression of the hemidiaphragm.

52. What is a catamenial pneumothorax?
Catamenial pneumothorax is a condition of air leaking into the pleural space occurring in conjunction with menstrual periods, believed to be caused primarily by endometriosis of the pleura.

53. What are the major causes of a pneumothorax?
A penetrating chest wound (e.g., gunshot, stabbing), barotrauma to the lungs (when exposed to sudden contractions or expansions of air), spontaneously (most commonly in tall, slim young males), chronic lung pathologies including emphysema, asthma, cystic fibrosis; acute or chronic infections, such as tuberculosis; and cancer.

54. What makes a non-tension pneumothorax different from a tension pneumothorax?
It’s a less severe pathology because air is able to escape.

55. What are the clinical manifestations of a tension pneumothorax?
The diaphragm is depressed on the affected side, and breath sounds are absent on the affected side.

56. What is a non-tension pneumothorax?
It occurs spontaneously, meaning there is no traumatic injury to the chest or lung.

57. What increases the risk of primary spontaneous pneumothorax?
Smoking

58. What is the most common cause of secondary spontaneous pneumothorax?
Parenchymal destruction in COPD

59. What happens to mediastinum in a tension pneumothorax?
Mediastinal structures get compressed, and the structures, such as the trachea, get shifted away from the affected lung.

60. Why can a tension pneumothorax lead to jugular venous distention?
Obstruction of the superior vena cava leads to decreased venous return, resulting in the jugular veins becoming distended.

61. What treatment is done for a tension pneumothorax?
Needle decompression and chest tube placement

62. What is a hemothorax?
A condition where blood leaks into the pleural cavity.

63. What is chylothorax?
A condition where lymph leaks into pleural space.

64. What are the chest percussion findings of a pneumothorax, hemothorax, and chylothorax?
Pneumothorax has a hyper-resonant percussion note on the affected side, while hemothorax and chylothorax have dull percussion notes.

65. For a patient with a tension pneumothorax, should a chest x-ray be performed first?
No, this is a medical emergency, and you should not delay treatment.

66. What is the difference between a primary and secondary pneumothorax?
Primary pneumothorax is without a precipitating event in the absence of lung disease, while secondary pneumothorax occurs as a complication of underlying lung disease.

67. How do you aspirate a pneumothorax?
Insert a large-bore needle with a syringe partially filled with saline into the 2nd intercostal space at the midclavicular line.

68. What is the most appropriate initial management of a patient with pneumothorax?
Oxygen therapy and aspiration using a 16G cannula inserted into the 2nd anterior intercostal space at the mid-clavicular line.

69. What are some procedures which may lead to iatrogenic pneumothorax?
CT-guided lung biopsy, transbronchial lung biopsy, and pleural aspiration.

70. What does a tension pneumothorax cause if left untreated?
Impaired venous return and decreased blood pressure and cardiac output, leading to PEA arrest.

71. What are the risk factors for spontaneous pneumothorax?
Male gender, height, smoking, and underlying lung disease.

72. How is increased height thought to contribute to a spontaneous pneumothorax?
It causes lower intrapleural pressure at the apex, increasing the risk of bleb development.

73. What sign is particularly seen in a tension pneumothorax?
Tracheal deviation

74. What is a chest tube?
A chest tube is a flexible plastic tube inserted through the chest wall into the pleural space. It’s used to drain air, blood, pus, or other fluids, restoring normal pressure in the chest and allowing the lung to re-expand.

75. What is the most common immediate symptom of a pneumothorax?
The most common immediate symptom of a pneumothorax is sudden, sharp chest pain.

Final Thoughts

A pneumothorax is a serious medical condition that demands immediate attention. Recognizing the signs such as sudden chest pain and shortness of breath is key to timely intervention.

Treatment strategies, which may include observation, needle aspiration, or surgery, depend on the severity and the underlying cause of the pneumothorax.

With an appropriate medical response, the prognosis for most patients is positive, highlighting the importance of awareness and quick action in managing this potentially critical condition.