Pneumothorax: collapsed lung — recognition, management and AU guidelines

A pneumothorax — collapsed lung — occurs when air enters the pleural space, the normally sealed cavity between the lung’s outer surface and the chest wall lining. Ordinarily this space contains only a thin film of lubricating fluid. When air collects there it pushes the lung inward, reducing breathing capacity. In its most dangerous form — tension pneumothorax — the air cannot escape, mediastinal structures shift, and venous return to the heart is compromised until circulation fails.

The Thoracic Society of Australia and New Zealand (TSANZ) classifies pneumothorax into four main clinical types: primary spontaneous (no apparent underlying lung disease), secondary spontaneous (in the setting of existing lung disease), traumatic or iatrogenic (from injury or medical procedures), and tension pneumothorax (a medical emergency). Each type has a different risk profile, natural history, and management path.

Recognition in general practice matters for two reasons. First, a patient with sudden pleuritic chest pain and breathlessness may present to the GP before reaching an emergency department. Second, tension pneumothorax is one of the rare conditions in clinical practice where a delay of minutes — to arrange imaging rather than acting on clinical findings — can be fatal.

A. Core clinical — the AU general-practice framework

Classification and who is at risk

Primary spontaneous pneumothorax (PSP) affects approximately seven men and one woman per 100,000 annually in Australia. It is most common in tall thin men aged 20–40, with smoking substantially increasing risk — approximately 22 times the baseline rate in heavy smokers. Most cases arise from rupture of small sub-pleural bullae or blebs at the apex, often invisible on plain chest X-ray but identifiable on CT.

Secondary spontaneous pneumothorax (SSP) develops in people with established lung disease. COPD accounts for approximately 70% of SSP cases, followed by asthma, cystic fibrosis, interstitial lung disease, and pulmonary malignancy. SSP carries higher morbidity and mortality because respiratory reserve is already compromised by the underlying condition.

Traumatic and iatrogenic pneumothorax can complicate central venous catheter insertion, pleural biopsy, mechanical ventilation with high peak pressures, or transthoracic needle biopsy. General practitioners requesting or following up these procedures should counsel patients about this recognised complication and the symptoms requiring urgent return.

Catamenial pneumothorax is a rare entity in women of reproductive age, associated with thoracic endometriosis, and typically occurs in the 24–48 hours surrounding menstruation.

Symptoms and signs

Typical presentation:

• Sudden pleuritic chest pain (approximately 95% of PSP cases) — sharp, one-sided, worse with breathing
• Breathlessness (approximately 80%; more severe in SSP)
• Dry cough (approximately 30%)
• Onset often at rest, or with a sneeze or Valsalva manoeuvre

Examination findings in stable pneumothorax:

• Hyperresonant percussion note on the affected side (contrasting with the dullness of pleural effusion)
• Diminished or absent breath sounds ipsilaterally
• Reduced chest expansion on the affected side
• Tachycardia and oxygen desaturation if significant

Tension pneumothorax — recognise and act immediately:

• Severe respiratory distress with rapid deterioration
• Tachycardia and hypotension (cardiovascular compromise)
• Elevated jugular venous pressure
• Tracheal deviation away from the affected side
• Absent breath sounds on the affected side

Tension pneumothorax is a clinical diagnosis — do not wait for chest X-ray confirmation before beginning decompression. This is the most important rule in managing this condition.

Diagnosis in the stable patient

Erect chest X-ray (PA and lateral) is first-line investigation. It shows the visceral pleural line with an absence of lung markings peripheral to it. The BTS 2023 guidelines — which inform Australian practice — define size by the rim of air measured at the hilum: small is less than 2 cm; large is 2 cm or more.

Bedside lung ultrasound (POCUS) has high sensitivity for pneumothorax in experienced hands. Absence of pleural sliding is the cardinal sign; the “lung point” — where the sliding pleura meets the static pneumothorax — is pathognomonic. POCUS avoids radiation and is increasingly available in Australian emergency departments.

CT chest is the gold standard for identifying underlying bullae, characterising SSP, and planning surgery in recurrent or complex cases.

Management decision framework

Tension pneumothorax:

1. Call 000 and prepare for immediate decompression
2. Insert a 14G cannula at the second intercostal space, midclavicular line OR the fifth intercostal space, anterior axillary line — both are accepted positions; emerging evidence supports the fifth intercostal space as more reliable in adults due to chest wall thickness
3. Follow immediately with formal intercostal drain insertion
4. Transfer to hospital for ongoing care

PSP small (<2 cm rim) with minimal symptoms — conservative management:

• PSP-1 trial NEJM 2020 supports conservative observation as non-inferior to intervention
• 4-hour emergency department observation with repeat chest X-ray
• High-flow supplemental oxygen accelerates resorption of pleural air
• Discharge if stable, with outpatient review and repeat X-ray at 2–4 weeks

PSP large (≥2 cm) or symptomatic:

• Needle aspiration (8 French catheter) is first-line per BTS 2023 — outpatient management possible if aspiration succeeds
• Small-bore intercostal catheter (Pleurocath, ≤14 Fr) is an alternative
• Large-bore chest drain reserved for failed aspiration or persistent air leak
• Admission for monitoring

SSP (any size if causing symptoms):

• Intercostal drain and hospital admission are almost always necessary
• Concurrent treatment of underlying lung disease
• Respiratory specialist review in hospital and at follow-up

B. Evidence: conservative versus active management in PSP

The PSP-1 trial (Roberts et al., New England Journal of Medicine, 2020) was a multicentre randomised controlled trial enrolling 316 patients with a first episode of primary spontaneous pneumothorax. Patients were randomised to conservative management (observation without any intervention) or active intervention (aspiration or drain at the clinician’s discretion). At eight weeks, radiographic re-expansion was achieved in 94.4% of the conservative group and 98.5% of the intervention group — a pre-specified non-inferiority margin was met. Complications were significantly lower with conservative management (7.6% versus 29.3%), and patients in the conservative arm returned to usual activities sooner.

This trial fundamentally shifted management of appropriately selected PSP. Prior Australian practice defaulted to intervention; current BTS 2023 and TSANZ guidance now recommends conservative management as the preferred initial approach for minimal-symptom small-to-moderate PSP.

For symptomatic or large PSP requiring intervention, studies comparing needle aspiration with chest drain insertion consistently support aspiration as first-line — it avoids hospitalisation for most patients, reduces procedure-related complications, and achieves equivalent success rates at one week in a majority of patients.

Areas of ongoing discussion:

• Whether CT chest is warranted after every first PSP (to identify bullae for future surgical planning) or should be reserved for recurrent or atypical presentations — current guidelines favour selective CT
• Optimal timing of video-assisted thoracoscopic surgery (VATS) pleurodesis after a first episode — most guidelines reserve VATS for first recurrence, persistent leak, or high-risk occupations

C. Recurrence prevention and activity restrictions

Recurrence and pleurodesis

Approximately 30% of PSP patients experience a second episode within five years; for SSP the recurrence rate approaches 50%. VATS (video-assisted thoracoscopic surgery) with pleurodesis — either mechanical pleurodesis or talc pleurodesis — reduces recurrence by approximately 90% and is the most effective preventive strategy for those who qualify.

Indications for referral for pleurodesis:

• First recurrence of PSP after an initial conservative or aspiration-managed episode
• Persistent air leak beyond five days
• Bilateral pneumothorax (simultaneous or sequential)
• Professional pilot or commercial diver (where recurrence risk is unacceptable for occupational or safety reasons)
• Occupations where sudden incapacity from recurrence would endanger others

Smoking cessation is the most accessible recurrence prevention step. Lung Foundation Australia supports patients with lung conditions, and the RACGP green book provides evidence-based cessation frameworks. Nicotine replacement therapy, varenicline, and bupropion are all PBS-listed options.

Aviation and diving restrictions

Flying is prohibited until at least one week after imaging confirms complete lung re-expansion. The Civil Aviation Safety Authority (CASA) and international aviation medicine organisations both enforce this restriction. At altitude, residual pleural air expands (Boyle’s Law), and a small pneumothorax can develop into a tension pneumothorax during descent or turbulence. Commercial pilots require review by a Designated Aviation Medical Examiner.

Scuba diving is a different matter. The South Pacific Underwater Medicine Society (SPUMS) — Australia’s reference diving medicine authority — regards a history of spontaneous pneumothorax as a permanent contraindication to scuba diving in most cases. The pressure differentials during descent and ascent carry a prohibitive barotrauma risk. This must be communicated clearly and documented in the medical record.

Strenuous activity and Valsalva: patients should avoid heavy lifting, vigorous exercise, and activities causing straining for at least two weeks after complete re-expansion.

D. Australian operations

Follow-up schedule:

• Chest X-ray at 2–4 weeks post-discharge to confirm re-expansion
• Respiratory physician review at 3 months for SSP, bilateral, or recurrent PSP
• Annual review for SSP patients with ongoing lung disease such as COPD

MBS billing in general practice:

• Standard consultation (initial assessment and follow-up): items 23, 36, 44
• Chest X-ray ordered from general practice: item 58500
• Spirometry when underlying COPD or asthma is suspected: items 11505/11506
• Telehealth follow-up consultations: items 91890/91891
• Mental Health Treatment Plan if post-pneumothorax anxiety warrants psychological referral: items 2715/2717
• Annual health assessment for chronic lung disease: item 715 for eligible patients

PBS-listed smoking cessation supports: nicotine replacement therapy (patches, gum, lozenge), varenicline (Champix), and bupropion (Zyban) are all PBS-listed for smoking cessation — critical for recurrence prevention after PSP.

Referral pathway:

• Suspected tension pneumothorax → 000 immediately
• Symptomatic or large PSP, any SSP, any trauma → emergency department the same day
• Post-recovery recurrence planning → respiratory physician referral
• Professional pilot or diver → aviation medical examiner or diving medicine specialist

E. Special populations

Older adults with COPD (SSP): secondary spontaneous pneumothorax in COPD causes disproportionate distress because respiratory reserve is already compromised. Even a small pneumothorax that might be managed conservatively in a young healthy person typically requires drainage and admission in an older patient with significant COPD. Post-discharge pulmonary rehabilitation supports recovery of function. Lung Foundation Australia offers COPD-specific resources and support programmes.

Pregnancy: pneumothorax in pregnancy carries risk for both the mother and developing baby due to hypoxia. Early specialist consultation involving both obstetrics and respiratory medicine is essential. Most invasive management — needle aspiration, intercostal drain — is safe during pregnancy. Maternal oxygen supplementation takes priority to protect fetal perfusion.

Marfan syndrome and heritable connective tissue disorders: these groups have elevated rates of PSP and bilateral disease, often at younger ages. Coordinated care involving the relevant specialist — cardiologist or clinical geneticist — is recommended, and VATS pleurodesis is often appropriate earlier in the disease course than in otherwise healthy individuals.

Young people and adolescents: PSP in adolescents is managed along the same principles as in adults. Flying and diving restrictions apply equally. Smoking cessation conversations should be age-appropriate and involve family support where clinically appropriate. Consider whether psychological support would assist adjustment to the diagnosis and restrictions.

Aboriginal and Torres Strait Islander people: coordinate care through Aboriginal Community Controlled Health Services where relevant. Closing the Gap PBS co-payment measure applies to smoking cessation pharmacotherapy, reducing cost barriers. Cultural safety and community support networks should be considered in the follow-up plan.

When to escalate

Call 000 immediately for:

• Any clinical features of tension pneumothorax — severe distress, falling blood pressure, tracheal deviation, raised jugular venous pressure — treat before imaging
• Bilateral pneumothorax
• Significant hypoxia (SpO₂ below 90% not correcting with supplemental oxygen)
• Pneumothorax in pregnancy
• Haemodynamic compromise at any point

Emergency department the same day for:

• Any PSP with more than minimal symptoms
• Any secondary spontaneous pneumothorax regardless of size
• Any traumatic or iatrogenic pneumothorax
• Recurrent pneumothorax

Semi-urgent specialist referral for:

• Planning VATS pleurodesis after first recurrence or special circumstances
• Catamenial pneumothorax — respiratory and gynaecology input needed
• Ongoing breathlessness after clinical resolution of the acute episode

What this article is and is not

This is general health information drawn from the British Thoracic Society 2023 Pleural Disease Guidelines, Therapeutic Guidelines (eTG), Thoracic Society of Australia and New Zealand (TSANZ), Australasian College for Emergency Medicine (ACEM), and the Roberts PSP-1 NEJM 2020 randomised controlled trial. It is not personal medical advice and does not create a doctor–patient relationship. Specific management decisions are made with your treating general practitioner, emergency physician, and respiratory specialist.

Australian consumer health resources: Lung Foundation Australia, HealthDirect — Pneumothorax, Better Health Channel, TSANZ.

If you think you may be having a pneumothorax with severe symptoms — call 000 immediately.

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Sources cited

1. British Thoracic Society 2023 — Pleural Disease Guidelines
2. Thoracic Society of Australia and New Zealand (TSANZ)
3. Roberts DJ et al. — Conservative vs interventional treatment for PSP. NEJM 2020
4. Therapeutic Guidelines (eTG)
5. Lung Foundation Australia
6. South Pacific Underwater Medicine Society (SPUMS)
7. Civil Aviation Safety Authority (CASA)
8. Australasian College for Emergency Medicine (ACEM)
9. HealthDirect — Pneumothorax
10. Better Health Channel
11. NPS MedicineWise — smoking cessation