Tension pneumothorax
Tension pneumothorax is a one-way pleural air leak that progressively raises intrapleural pressure, shifts the mediastinum, and collapses venous return, producing obstructive shock. It is a clinical diagnosis treated with immediate needle or finger decompression, never delayed for imaging.
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What this article covers
- Overview
A one-way valve, not just air in the pleural space: tension pneumothorax is the physiologic emergency variant of pneumothorax in which a pleural or bronchopleural defect lets air enter the pleural…
- Epidemiology
Most common in trauma and ventilated patients: tension physiology arises most often after blunt or penetrating chest trauma and in mechanically ventilated patients receiving positive-pressure…
- Risk factors
Positive-pressure mechanical ventilation: the single strongest driver of a one-way air leak converting to tension physiology, because each ventilator breath forces additional air across the pleural defect.
- Pathophysiology
One-way valve mechanism: a flap of pleura, lung, or chest wall tissue opens on inspiration (negative pleural pressure draws air in) and closes on expiration (positive pleural pressure seals the…
- Clinical features
Significant, often sudden, cardiorespiratory distress: severe dyspnea, tachypnea, and anxiety out of proportion to a simple pneumothorax.
- Differential diagnosis
Cardiac tamponade: also produces obstructive shock with distended neck veins, but breath sounds are bilateral and present, heart sounds are muffled, and pulsus paradoxus (systolic pressure drop of 10…
- Diagnosis
Tension pneumothorax is a clinical diagnosis made at the bedside: significant cardiorespiratory distress plus hypotension, absent breath sounds on one side, tracheal deviation, and/or distended neck…
- Management
First, give high-flow supplemental oxygen while continuously monitoring vital signs; do not delay for imaging or labs.
- Complications
Cardiac arrest from untreated obstructive shock: progressive venous return failure leads to pulseless electrical activity if decompression is delayed; tension pneumothorax is one of the reversible…
- Prognosis
Rapidly fatal if untreated: obstructive shock and cardiac arrest occur within minutes once venous return is critically compromised, making this one of the few true "seconds count" diagnoses in acute care.
- Prevention
Maintain a high index of suspicion in every ventilated patient with sudden hypotension and rising airway pressures, and examine immediately rather than waiting for imaging.
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Related articles
- Pneumothorax
Pneumothorax is air in the pleural space, occurring spontaneously (primary in structurally normal lungs, secondary in underlying lung disease) or from trauma or procedures. Management is driven by size and hemodynamic stability, ranging from observation to needle aspiration to tube thoracostomy.
- Hemothorax
Hemothorax is blood in the pleural space, most often from blunt or penetrating chest trauma, defined by a pleural fluid hematocrit above 50% of the peripheral hematocrit. Each hemithorax can hold up to 40% of circulating blood volume, so massive hemothorax is a hemorrhagic-shock emergency treated with simultaneous chest tube thoracostomy and resuscitation, with operative thoracotomy triggered by fixed drainage thresholds.
- Cardiac tamponade
Cardiac tamponade is life-threatening compression of the heart by a pericardial effusion, impairing diastolic filling and cardiac output. It presents with hypotension, distended neck veins, and pulsus paradoxus, is confirmed by echocardiography, and is treated by urgent pericardiocentesis; avoid vasodilators and aggressive diuresis.
- Mechanical ventilation
Invasive and noninvasive positive pressure ventilation support gas exchange and reduce work of breathing in hypoxemic or hypercapnic respiratory failure, upper airway impairment, or inability to protect the airway.