Tension Pneumothorax

A 32-year-old man is brought to the emergency department after a motor vehicle collision. He has severe dyspnea and chest pain. He appears distressed and tachypneic. Vital signs show hypotension and tachycardia. On examination, breath sounds are markedly decreased on the right side, and percussion is hyperresonant. The trachea is deviated to the left, and jugular venous distension is present. Diagnosis? 

Diagnosis is Tension Pneumothorax.

1. Definition

Tension pneumothorax is a life-threatening condition caused by a one-way valve air leak that allows air to enter but not exit the pleural space, leading to progressive intrathoracic pressure, lung collapse, mediastinal shift, and obstructive shock.

2. Etiology

1. Trauma
• Rib fractures
• Penetrating chest injury
2. Iatrogenic causes
• Central venous catheter placement
• Thoracentesis
3. Mechanical ventilation (positive pressure ventilation)
• Barotrauma
4. Spontaneous pneumothorax (rare progression)

3. Pathophysiology

1. Air enters pleural space via one-way valve mechanism
2. Progressive increase in intrathoracic pressure
3. Compression of ipsilateral lung
4. Mediastinal shift to opposite side
5. Compression of vena cava → decreased venous return
6. Leads to obstructive shock

4. Clinical Features

4.1 Core Features

1. Sudden severe dyspnea
2. Tachypnea
3. Hypotension
4. Tachycardia

4.2 Examination Findings

1. Decreased or absent breath sounds on affected side
2. Hyperresonance to percussion
3. Tracheal deviation away from affected side (late sign)
4. Jugular venous distension (JVD)
5. Signs of shock

5. Diagnosis

Tension pneumothorax is a clinical diagnosis in an unstable patient.

➡ Do NOT delay treatment for imaging

5.1 Imaging (only if patient is stable)

1. Chest X-ray
• Collapsed lung
• Absent lung markings
• Mediastinal shift away from affected side
• Hyperlucent hemithorax
2. Bedside lung ultrasound
• Absence of lung sliding
3. CT chest
• Not routinely required
• Used only in stable or unclear cases

6. Management

6.1 Immediate Management (Life-saving)

1. Immediate needle decompression
• Preferred site:
• 4th or 5th intercostal space in the anterior or mid-axillary line
• Alternative site:
• 2nd intercostal space in the midclavicular line

➡ Perform immediately without waiting for imaging

6.2 Definitive Management

1. Tube thoracostomy (chest tube placement)
• Inserted in the triangle of safety

6.3 Supportive Care

1. Airway, Breathing, Circulation (ABC)
2. High-flow oxygen
3. Hemodynamic stabilization

7. Complications

1. Obstructive shock
2. Cardiac arrest
3. Respiratory failure

8. Key Clinical Insight

A patient with acute dyspnea, hypotension, unilateral absent breath sounds, and possible tracheal deviation should be treated immediately for tension pneumothorax without waiting for imaging

9. Exam-Level Pearls

1. Tension pneumothorax is a clinical diagnosis
2. Do NOT delay decompression for imaging
3. Needle decompression is life-saving
4. Tracheal deviation is a late finding
5. JVD reflects obstructive shock physiology
6. Definitive treatment is chest tube placement
7. Most common mistake is ordering imaging before treatment