Tension Pneumothorax

Characterized by the progressive accumulation of air within the pleural space that cannot escape

Etiology

Tension pneumothorax may result from:
  1. Thoracic trauma
      • Blunt trauma
      • Penetrating injuries
  1. Iatrogenic pneumothorax
      • Mechanical ventilation (barotrauma)
      • Central venous catheter insertion
      • Lung biopsy
  1. Spontaneous pneumothorax
      • Primary (rupture of subpleural blebs)
      • Secondary (COPD, severe asthma, pulmonary tuberculosis, interstitial lung disease)

Risk Factors

  • Chronic obstructive pulmonary disease
  • Positive-pressure ventilation
  • Previous pneumothorax
  • Severe chest trauma

Pathophysiology

The pathophysiological process occurs in a progressive sequence:
  1. Air enters the pleural space
  1. A one-way valve effect traps air within the pleural cavity
  1. Progressive rise in intrapleural pressure
  1. Collapse of the ipsilateral lung
  1. Mediastinal shift toward the contralateral side
  1. Compression of the superior and inferior vena cava
  1. Reduced venous return to the heart
  1. Decreased cardiac output
  1. Development of obstructive shock
If untreated, this sequence may culminate in cardiac arrest and death.
notion image

Clinical presentation

Symptoms

  • Severe, rapidly progressive dyspnea
  • Pleuritic chest pain
  • Sense of air hunger
  • Extreme anxiety

Signs

  • Tachypnea and hypoxemia
  • Tachycardia
  • Hypotension
  • Distended neck veins
  • Tracheal deviation away from the affected side (late sign)
  • Hyperresonance on percussion
  • Decreased or absent unilateral breath sounds
  • Cyanosis in advanced stages

Management

Needle Decompression

  • Traditional site: 2nd intercostal space, midclavicular line
  • Alternative site: 4th or 5th intercostal space, anterior axillary line
  • Large-bore needle (≥14-gauge)

Tube Thoracostomy (Chest Tube Insertion)

  • Performed following needle decompression
  • Definitive management
  • Connected to a water-seal drainage (WSD) system

Supportive Therapy

  • High-flow oxygen
  • Hemodynamic support as needed
  • Treatment of the underlying cause