Tension Pneumothorax Recognition

Why This Is Hard

Classic textbook signs appear late. Waiting for tracheal deviation means waiting too long. Tension physiology is obstructive shock: rising intrapleural pressure collapses the lung, shifts the mediastinum, kinks venous return, and drops cardiac output. Patients die from shock, not from an interesting x-ray finding you will never see in the field.

Positive-pressure ventilation (BVM or ventilator) can convert a simple pneumothorax into tension physiology — keep that in mind after intubation in trauma and severe asthma/COPD.

Pattern Recognition (Field)

• Mechanism: chest trauma (blunt or penetrating), blast, rib fractures, spontaneous in tall thin patients or known bullae, positive-pressure ventilation.
• Progressive dyspnea, hypoxia, agitation, air hunger.
• Unilateral decreased breath sounds; hyperresonance possible (hard in noisy scenes).
• Increasing difficulty bagging / high resistance after intubation on one side.
• JVD, hypotension, signs of obstructive shock as it worsens.
• Subcutaneous emphysema may be present with airway/chest injury — supportive clue only.
• Tracheal deviation is late — do not require it to act on a clear picture per training/protocol.

Do Not Tunnel Vision

• Simple pneumothorax without tension — may not need field needle decompression; support and transport per protocol.
• Hemothorax — may have dullness; neck veins can be flat from blood loss; decompression does not fix major blood in the chest.
• Right mainstem intubation — check depth; bilateral sounds after withdrawal; EtCO₂ still present.
• Pericardial tamponade — different context; equal breath sounds, other clues; needle decompression will not fix it.
• Massive PE / cardiogenic shock — obstructive or pump failure without unilateral chest findings.
• Severe asthma — bilateral air trapping can make bagging hard; not always tension on one side.

EMS Action Framing (Education)

1. Support ABCs; high-flow O₂ as indicated; minimize unnecessary positive pressure if possible until decompression when tension is clear.
2. If tension is identified and you are authorized, needle thoracostomy only per training and protocol (site — often midclavicular 2nd ICS or midaxillary sites per current local training — catheter length, technique, reassessment).
3. Reassess breath sounds, bag compliance, BP, mentation, SpO₂, EtCO₂.
4. Rapid transport; watch for recurrence — catheters kink and obstruct; some systems allow finger thoracostomy or repeat decompression per protocol/training only.
5. Treat coexisting hemorrhage and shock; tension can coexist with bleeding.

This lesson does not teach the procedural skill — it builds recognition and decision framing for the paramedic team. Hands-on needle decompression belongs in authorized training with your medical director’s protocol.

Team Communication

• “Right chest trauma, decreasing right sounds, hard to bag, hypotensive — treating as tension, preparing decompression per protocol.”
• After intervention: “Improved bag compliance and BP” or “no change — reconsidering differential / second site per protocol.”

Field Pitfalls

• Waiting for tracheal deviation.
• Needle decompression for hypoxia alone without a tension picture.
• Wrong side or insufficient catheter length in large chest walls (know your equipment and training updates).
• No reassessment after the procedure.
• Missing mainstem intubation as the cause of unilateral sounds.

Practice

Talk through two scenarios: (1) stab wound + shock + unilateral findings; (2) post-intubation sudden hard bagging. State whether you would decompress under your protocol and what you reassess. Related: Shock categories, Failed oxygenation.

Sources & Further Study

• ATLS / trauma education on tension pneumothorax.
• Your needle decompression protocol, preferred sites, and hands-on training.