Pneumothorax

What is the general definition of a pneumothorax?

A collection of air within the pleural space between the lung (visceral pleura) and the chest wall (parietal pleura), potentially leading to pulmonary collapse. Definitions 1

How is a primary spontaneous pneumothorax defined?

A spontaneous pneumothorax that occurs in patients without clinically apparent underlying lung disease. Definitions 2

How is a secondary spontaneous pneumothorax defined?

A spontaneous pneumothorax that occurs as a complication of underlying lung disease. Definitions 3

How is a traumatic pneumothorax defined?

A type of pneumothorax caused by trauma (e.g., penetrating injury, iatrogenic trauma). Definitions 4

How is a tension pneumothorax defined?

A life-threatening pneumothorax variant with progressively increasing intrathoracic pressure and cardiorespiratory compromise. Definitions 5

What is the peak age incidence and sex predilection for primary spontaneous pneumothorax?

Peak incidence is 16-25 years; affects males more than females (approx. 6:1). Epidemiology 6

What is the peak age incidence and sex predilection for secondary spontaneous pneumothorax?

Peak incidence is 60-65 years; affects males more than females (approx. 3:1). Epidemiology 7

What is the typical cause of a primary spontaneous pneumothorax?

Caused by ruptured subpleural apical blebs. Etiology 8

List three major risk factors for primary spontaneous pneumothorax.

Family history, male sex, young age, asthenic body habitus (slim, tall), or smoking (90% of cases). (Any 3) Etiology 9

What underlying lung condition is a common cause of secondary spontaneous pneumothorax?

COPD (smoking), often due to rupture of bullae in emphysema. Etiology 10

Name two infectious causes of secondary spontaneous pneumothorax.

Pulmonary tuberculosis or Pneumocystis pneumonia (PJP). Etiology 11

What rare condition involving the diaphragm can cause catamenial pneumothorax?

Thoracic endometriosis. Etiology 12

List two causes of iatrogenic pneumothorax.

Mechanical ventilation (barotrauma), thoracocentesis, central venous catheter placement, bronchoscopy, or lung biopsy. (Any 2) Etiology 13

What is the initial pathophysiological consequence of increased intrapleural pressure in pneumothorax?

Alveolar collapse, leading to decreased V/Q ratio and increased right-to-left shunting. Pathophysiology 14

What mechanism allows air entry in an open traumatic pneumothorax?

Air enters through a lesion in the chest wall during inspiration and leaks out during expiration. Pathophysiology 15

What mechanism causes progressive air accumulation in a tension pneumothorax?

A one-way valve mechanism where air enters the pleural space on inspiration but cannot exit. Pathophysiology 16

What are the critical hemodynamic consequences of a tension pneumothorax?

Reduced venous return to the heart, reduced cardiac output, hypoxia, and hemodynamic instability (shock). Pathophysiology 17

What are the typical symptoms of a pneumothorax?

Sudden, severe, and/or stabbing, ipsilateral pleuritic chest pain and dyspnea. Clinical Feat. 18

What are characteristic findings on physical examination of the affected side in pneumothorax?

Reduced or absent breath sounds, hyperresonant percussion, and decreased tactile fremitus. Clinical Feat. 19

What additional physical findings strongly suggest a tension pneumothorax?

Severe respiratory distress (cyanosis, restlessness), distended neck veins, hemodynamic instability (tachycardia, hypotension), reduced ipsilateral chest expansion. Clinical Feat. 20

In ventilated patients, what signs might indicate a developing tension pneumothorax?

Tachycardia, hypotension, JVD, rapid decrease in SpO2, reduced air flow, increased ventilation pressure, or skin emphysema. Clinical Feat. 21

What does the mnemonic P-THORAX stand for regarding pneumothorax features?

Pleuritic pain, Tracheal deviation, Hyperresonance, Onset sudden, Reduced breath sounds (& dyspnea), Absent fremitus, X-ray shows collapse. Clinical Feat. 22

What is the primary diagnostic approach for suspected pneumothorax?

Diagnosis is usually confirmed by chest x-ray (upright PA view preferred). Ultrasound (eFAST) is increasingly used. CT provides more detail. Diagnosis 23

How should suspected tension pneumothorax be diagnosed and managed initially?

Tension pneumothorax is primarily a clinical diagnosis; initiate immediate treatment (decompression) without delaying for imaging. Diagnosis 24

What is the key finding on chest x-ray confirming a pneumothorax?

A visible ipsilateral pleural line with absent lung markings peripheral to it. Diagnosis / CXR 25

What is the "deep sulcus sign" on a supine chest x-ray suggestive of pneumothorax?

Deepening of the costophrenic angle on the affected side due to air collecting basally. Diagnosis / CXR 26

What chest x-ray findings suggest a tension pneumothorax?

Ipsilateral diaphragmatic flattening/inversion, widened intercostal spaces, mediastinal shift to the contralateral side, and tracheal deviation to the contralateral side. Diagnosis / CXR 27

What findings on point-of-care ultrasound (POCUS) support a pneumothorax diagnosis?

Absence of pleural sliding ("lung sliding") and absence of B-lines. (May see prominent A-lines). Diagnosis / US 28

When is chest CT indicated for evaluating pneumothorax?

For uncertain diagnosis after CXR/ultrasound, complex cases, suspected underlying lung disease (bullae), or presurgical workup. Diagnosis / CT 29

When is Arterial Blood Gas (ABG) analysis indicated in pneumothorax?

Indicated if SpO2 < 92% on room air or to evaluate for CO2 retention in patients with underlying lung disease receiving oxygen. Diagnosis / Labs 30

What is pneumomediastinum?

The presence of gas (usually air) in the mediastinum. Differential 31

What is Hamman sign, associated with pneumomediastinum?

Precordial crepitation (crackling sound) heard synchronous to the heartbeat. Differential 32

How is pneumomediastinum typically managed?

Usually self-limited when associated with barotrauma; involves clinical/radiographic monitoring and ventilation pressure reduction if applicable. Trauma requires specific management. Differential 33

What is the first step in managing unstable patients or those with high-risk pneumothorax (tension, bilateral, ventilated)?

Immediate chest decompression. Treatment 34

What immediate intervention must be performed for any pneumothorax patient requiring mechanical ventilation?

Immediate tube thoracostomy (chest tube placement) must be performed before initiating positive pressure ventilation. Treatment 35

What respiratory support is generally provided for pneumothorax patients?

Upright positioning and supplemental high-flow oxygen (target SpO2 ≥ 96-100%). Treatment 36

What criteria define a stable patient with spontaneous pneumothorax?

RR < 24, SpO2 > 90% (room air), able to speak full sentences, HR 60-120, normal BP. Treatment 37

What is the immediate treatment for suspected tension pneumothorax?

Emergency needle thoracostomy, followed immediately by chest tube placement. (Consider finger thoracostomy if needle fails). Treatment 38

How is a stable primary spontaneous pneumothorax with apex-to-cupola distance < 3 cm typically managed?

Observation with repeat CXR at 3-6 hours. If stable/improving, consider outpatient management; if enlarging, place chest tube. Treatment 39

How is a stable primary spontaneous pneumothorax with apex-to-cupola distance ≥ 3 cm typically managed?

Chest tube placement is typically recommended. (Consider conservative management or needle aspiration in select healthy, reliable patients with first episode). Treatment 40

How is a stable secondary spontaneous pneumothorax typically managed?

Chest tube placement is generally recommended, especially if apex-to-cupola distance ≥ 3 cm. Consider observation only for very small (<3cm) cases. Admit to ICU, consult surgery. Treatment 41

Is observation appropriate for most traumatic pneumothoraces?

Observation is only considered in hemodynamically stable patients with small pneumothoraces. Most require a chest tube. Treatment 42

When is a chest tube required for traumatic pneumothorax?

Required for hemopneumothorax, ongoing/anticipated mechanical ventilation, moderate/large size, or hemodynamic instability with even a small pneumothorax. Treatment 43

How is an open pneumothorax ("sucking chest wound") initially managed?

Immediately apply a simple, partially occlusive dressing taped on 3 sides, followed by tube thoracostomy. Observe for tension pneumothorax development. Treatment 44

Where is a needle thoracostomy typically performed in adults?

2nd intercostal space, midclavicular line OR 4th-5th intercostal space, anterior-to-midaxillary line. Treatment 45

Where is chest tube placement typically performed (safe triangle)?

4th-5th intercostal space (nipple line), between the anterior and midaxillary line. Treatment 46

What are potential complications of pneumothorax?

Complete pulmonary collapse/respiratory failure, tension pneumothorax/cardiac failure, hemothorax, pneumomediastinum, pneumoperitoneum, recurrence. Complications 47

What are potential complications related to chest tube placement or surgery for pneumothorax?

Persistent fistula/air leak, injury to intercostal nerves/vessels, infection. Complications 48