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Pneumothorax

Emergencies

Tension pneumothorax is a clinical diagnosis — decompress now, don't wait for an X-ray.

BTS 2023: manage by symptoms, not size alone. Conservative and ambulatory options are valid in the right patient.

Act now

  1. 1

    Suspected tension: needle decompression (4th–5th intercostal space, anterior to mid-axillary line, or 2nd space mid-clavicular), then chest drain.

  2. 2

    Oxygen to target if hypoxic.

  3. 3

    Analgesia.

Assess

  • ABCDE: breathlessness, pain, SpO₂, BP. Tension: shock, tracheal or apex beat deviation, severe distress.
  • Primary (no lung disease) or secondary (COPD, ILD, CF, or over 50 with smoking history)?
  • Size on CXR (interpleural distance at the hilum); CT if unclear.

Investigations

  • Erect CXR; CT if the diagnosis or size is uncertain, or bullous disease.
  • Blood gas if SpO₂ is low or the patient has lung disease.

Manage

  • Use the decision pathway below.
  • Pleural procedures with ultrasound guidance where possible.
  • Before discharge: written advice to return if breathless, no flying until resolution is confirmed, never dive unless definitive surgery, stop smoking.

Spontaneous pneumothorax (BTS 2023)

Haemodynamic compromise or suspected tension?

Escalate when

  • Tension, bilateral, secondary pneumothorax, failed aspiration, persistent air leak or haemopneumothorax: senior and respiratory team.

Written to current guidance · sources checked 14 Nov 2026. We watch NICE for updates weekly.

Sources (2)

Reviewed by Aboodee Alhasso, MPharm MRCPharm IP on 14 Nov 2026

Calculators for this

For healthcare professionals, as an aid to clinical judgement — not a substitute for it. Follow your local policy and ask a senior when in doubt.