Guide — Emergency Respiratory Care
Tension Pneumothorax Recognition & Management
A breath-by-breath emergency – how air trapped under pressure collapses the lung and shifts the mediastinum, the signs that separate a simple from a tension pneumothorax, why it is a clinical (not radiographic) diagnosis, and the needle decompression and chest tube that fix it. Real emergencies follow current ACLS and trauma protocols and physician orders.
8 min read · Emergency Respiratory Care
Written by Apex Respiratory Editorial Team
Educational use only. This material supports respiratory therapy education and exam review. It is not medical advice and is not a substitute for clinical judgment, institutional protocols, or physician orders. Always follow facility policies and current provider orders, and verify calculations independently before clinical use.
Overview
A tension pneumothorax occurs when air enters the pleural space and cannot escape – a one-way valve. The trapped air builds pressure that collapses the lung, shifts the mediastinum, and impairs venous return, producing obstructive shock and arrest if untreated. It is a clinical diagnosis that requires immediate decompression; do not wait for a chest X-ray.
Key Concepts
- Mechanism. A one-way leak (chest trauma, barotrauma from positive-pressure ventilation or high PEEP, central-line placement, or spontaneous rupture) traps air, so intrapleural pressure rises, the ipsilateral lung collapses, the mediastinum shifts to the opposite side, the great vessels kink, venous return falls, and obstructive shock follows.
- Simple versus tension. A simple pneumothorax is a collapsed lung without hemodynamic compromise; a tension pneumothorax adds mediastinal shift, hypotension, and shock.
- Ventilated patients are high risk. Positive pressure rapidly converts a small leak into tension. A sudden rise in peak pressure, a falling SpO₂, and hypotension on the ventilator should prompt immediate evaluation.
| Feature | Simple | Tension |
|---|---|---|
| Lung | Collapsed | Collapsed |
| Mediastinal shift | Absent | Present (shifts to opposite side) |
| Blood pressure | Maintained | Hypotension |
| Hemodynamics | Stable | Obstructive shock |
| Urgency | Treat per protocol | Immediate decompression |
Assessment & Findings
Classic signs are severe dyspnea, hypoxemia, absent or diminished breath sounds on the affected side, hyperresonant percussion, tracheal deviation AWAY from the affected side (a late sign), distended neck veins, hypotension and tachycardia, and – on the ventilator – a sudden rise in peak and plateau pressures. Tracheal deviation and distended neck veins are late signs; do not wait for them.
| Sign | Finding | Timing |
|---|---|---|
| Breath sounds | Absent or diminished on the affected side | Early |
| Percussion | Hyperresonant on the affected side | Early |
| Respiratory effort | Severe dyspnea, hypoxemia (falling SpO₂) | Early |
| Hemodynamics | Hypotension and tachycardia (obstructive shock) | Early |
| Ventilator | Sudden rise in peak and plateau pressures | Early |
| Tracheal deviation | Trachea shifts AWAY from the affected side | Late |
| Neck veins | Distended (impaired venous return) | Late |
RT Priorities & Interventions
- Immediate needle decompression. Use a large-bore catheter – traditionally the 2nd intercostal space at the midclavicular line, or the 4th–5th intercostal space at the anterior-to-midaxillary line per current trauma guidance – which converts a tension into a simple pneumothorax (a rush of air).
- Definitive treatment is a chest tube. Tube thoracostomy provides ongoing drainage and re-expands the lung.
- Oxygenate and support ventilation. Give high-flow or 100% oxygen and support ventilation.
- On the ventilator. If tension is suspected, reduce pressure or briefly disconnect and decompress, then reassess PEEP and peak pressures.
Decompression and chest-tube placement are performed under physician direction and current ACLS and trauma protocols; the RT’s role is rapid recognition, oxygenation, ventilator management, and assisting the procedure.
Common Pitfalls
- Waiting for a chest X-ray to confirm before decompressing an unstable patient – tension pneumothorax is a clinical diagnosis.
- Missing the ventilated patient whose sudden “deterioration” is a tension pneumothorax (rising peak pressure plus hypotension plus falling SpO₂).
- Forgetting that high PEEP, high peak pressures, and a recent line placement are classic setups.
Board Exam Pearls
- Tension pneumothorax is a clinical diagnosis – immediate needle decompression, then a chest tube.
- Signs: absent breath sounds and hyperresonance on the affected side, tracheal deviation AWAY (late), distended neck veins, and hypotension.
- Positive-pressure ventilation and high PEEP are major risk factors (barotrauma).
- On the ventilator: a sudden rise in peak pressure with a falling SpO₂ and blood pressure.
- Needle decompression: 2nd intercostal space midclavicular (classic) or 5th intercostal space anterior axillary (trauma).
FAQ
How is a tension pneumothorax different from a simple one?
A simple pneumothorax is a collapsed lung without hemodynamic compromise. In a tension pneumothorax, trapped air under rising pressure shifts the mediastinum, kinks the great vessels, and drops venous return - causing obstructive shock that is rapidly fatal without decompression.
Why not wait for a chest X-ray?
Tension pneumothorax is a clinical diagnosis. A patient with absent breath sounds, hyperresonance, hypotension, and distended neck veins needs immediate needle decompression - waiting for imaging can be fatal.
Why are ventilated patients at special risk?
Positive-pressure ventilation, especially with high PEEP or peak pressures, can rapidly turn a small air leak into a tension pneumothorax. A sudden rise in peak pressure with falling saturation and blood pressure on the ventilator should trigger immediate evaluation.
What does needle decompression accomplish?
Inserting a large-bore catheter into the pleural space lets the trapped air escape, converting a life-threatening tension pneumothorax back into a simple one and restoring venous return. A chest tube then provides definitive drainage.
Put it to work
On the ventilator, a tension pneumothorax shows up as a sudden rise in peak pressure and falling compliance. See how the mechanics read it.
Open the Compliance calculator →Related Resources
Sources
- Kacmarek RM, Stoller JK, Heuer AJ. Egan's Fundamentals of Respiratory Care. 12th ed. Elsevier; 2021. Pleural diseases, chest trauma, and lung expansion therapy chapters.
- Roberts DJ, Leigh-Smith S, Faris PD, et al. Clinical Presentation of Patients With Tension Pneumothorax: A Systematic Review. Ann Surg. 2015;261(6):1068-1078.