Tension pneumothorax

Learning objectives

Pneumothorax is the collapse of the lung when air accumulates between the parietal and visceral pleura inside the chest
Air outside the lung inside the thoracic cavity creates pressure on the lung and can lead to its collapse
Can be traumatic or iatrogenic
Tension pneumothorax: Shift in mediastinal structures, results from air under positive pressure trapped in the pleural space through a one-way valve system
Rare, life-threatening condition
Commonly occurs in intensive care unit ventilated patients

Iatrogenic	Central venous catheterization in the subclavian or internal jugular vein
	Lung biopsy
	Barotrauma due to positive pressure ventilation
	Percutaneous tracheostomy
	Thoracentesis
	Pacemaker insertion
	Bronchoscopy
	Cardiopulmonary resuscitation
	Intercostal nerve block
External trauma	Penetrating or blunt trauma
	Rib fracture
	Diving or flying
Other	Idiopathic spontaneous pneumothorax
	Open pneumothorax
	Conversion of spontaneous pneumothorax to tension

Sharp pleuritic pain that can radiate to the ipsilateral back or shoulder
Increased respiratory rate
Dyspnea
Retractions
Decreased or absent breath sounds, reduced tactile fremitus, hyper-resonant percussion sounds, and possibly asymmetrical lung expansion upon lung auscultation
Signs of hemodynamic instability with hypotension and tachycardia
Cyanosis
Jugular vein distension
Subcutaneous emphysema
In severe cases: acute respiratory failure, cardiac arrest

Patient hemodynamically unstable and in acute respiratory failure: Bedside ultrasound, stabilize patient and assess airway, breathing, and circulation
Patient hemodynamically stable: Chest X-ray:
- Effacement of lung markings distal to the edge of the visceral pleura
- Complete ipsilateral lung collapse
- Mediastinal shift away from the pneumothorax
- Subcutaneous emphysema
- Tracheal deviation to the contralateral side
- Flattening of the hemidiaphragm on the ipsilateral side
Diagnosis unclear on chest X-ray: Chest CT

Patient with chest trauma
- Assess airway, breathing, and circulation
- Cover penetrating chest wound with an airtight occlusive bandage and clean plastic sheeting
- Administer 100% supplemental oxygen
- Avoid positive pressure ventilation initially
- Positive pressure ventilation is possible after a chest tube is placed
Hemodynamically unstable patient
- Immediate needle decompression
- Chest X-ray after needle decompression
- Place chest tube
- If needle decompression fails: Video-assisted thoracoscopic surgery or thoracotomy
Hemodynamically stable patient
- Diagnostic imaging can be performed prior to treatment

Cardiac tamponade can clinically mimic tension pneumothorax
Patients with high peak inspiratory pressure are at greater risk of tension pneumothorax
There is a high suspicion of tension pneumothorax when the patient becomes hemodynamically unstable or goes into cardiac arrest
If a chest tube is malpositioned or becomes plugged, the pneumothorax can recur
Administer local anesthesia or adequate analgesia/sedation in stable patients