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Traumatic tension pneumothorax during positive-pressure ventilation — MRCEM SBA MCQ

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HardTraumaTraumatic tension pneumothorax during positive-pressure ventilationMRCEM SBA

A 34-year-old motorcyclist is assessed at a major trauma centre. While breathing spontaneously, he was haemodynamically stable; CT showed right-sided rib fractures, pulmonary contusion and a small right pneumothorax. He is subsequently intubated for worsening ventilation. Waveform capnography confirms tracheal intubation, and air entry is initially present on both sides. Shortly after positive-pressure ventilation begins, his oxygen saturation falls from 97% to 82% and his blood pressure from 118/76 to 72/44 mmHg. Right-sided air entry is now markedly reduced; left-sided air entry is preserved. A clinician skilled in thoracostomy is at the bedside. What is the most appropriate immediate chest-management sequence?

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Correct answer: E — Perform right open thoracostomy, then insert a chest drain.

The known right pneumothorax can enlarge under positive-pressure ventilation. Abrupt hypoxaemia and hypotension, together with newly reduced right-sided air entry, make a right tension pneumothorax the immediate working diagnosis. Initial bilateral air entry and continuing waveform capnography make an initially misplaced tracheal tube less persuasive. Because he has both severe respiratory compromise and haemodynamic instability, decompression must precede further imaging. For **in-hospital** tension pneumothorax, NICE recommends open thoracostomy followed by a chest drain. ([nice.org.uk](https://www.nice.org.uk/guidance/ng39/evidence/full-guideline-2308122833)) **A** is attractive because needle decompression can rapidly release pleural pressure, but it is not the preferred technique when open thoracostomy expertise is immediately available. **B** provides initial decompression but omits the subsequent drain required by the in-hospital recommendation; deferring a drain can be appropriate for a ventilated patient before hospital arrival. **C** could help assess a stable chest injury, but radiography delays treatment of suspected tension physiology here. **D** could augment assessment when the diagnosis is uncertain and the patient is stable enough for imaging, but eFAST must not delay decompression in this unstable patient. ([nice.org.uk](https://www.nice.org.uk/guidance/ng39/chapter/Recommendations))

Reference: Major trauma: assessment and initial management — recommendations 1.4.1–1.4.2 (17 February 2016) — https://www.nice.org.uk/guidance/ng39/chapter/Recommendations Major trauma: assessment and initial management — full guideline, assessment and management of chest trauma (2016) — https://www.nice.org.uk/guidance/ng39/evidence/full-guideline-2308122833