Author: Jason B Lee / Editor: Jason B Lee / Reviewer: Sarah Hickin-Yacoub, Caitriona Considine, Ahmad Alabood / Codes: ResC8, ResP1, ResP2, RP5, RP7, SLO1, SLO3, SLO6 / Published: 29/01/2024


The reported incidence of primary spontaneous pneumothoraces is 18-28 per 100 000 per year for men and 1-6 per 100,000 per year for women, though this data from Sweden and the USA is more than 20 years old. A more recent study in England and Wales [1] found the hospital admission rate for all spontaneous pneumothoraces to be 17 and 6 per 100 000 per year for men and women, respectively.

Changes in clinical guidelines since may have lead to a reduction in the proportion of patients admitted. The same study reported the mortality from spontaneous pneumothoraces in England and Wales between 1991 and 1995 to be 1.3 per million per year for men and 0.6 per million per year for women.


A pneumothorax is a collection of gas in the pleural space that results in a variable amount of lung collapse on the affected side. By definition, spontaneous pneumothoraces occur in the absence of any trauma (including iatrogenic causes) to the chest wall.

Primary spontaneous pneumothoraces occur in people with no underlying lung pathology.

Secondary spontaneous pneumothoraces occur in patients with pre-existing lung parenchymal or pleural pathology (e.g. asthma, lung carcinoma).


The pleura is a thin layer which lines each of the lungs (visceral pleura). It is reflected around the lung hila onto the chest wall and pericardium (parietal pleura) and extends from the root of the neck (~3 cm above the mid-point of the clavicle) to the 12th rib overlying the kidney. The parietal layer secretes approximately 2.5 litres of serous fluid a day, which is absorbed by the visceral layer so that at any given time only a small amount of fluid lines the space.

Primary Pneumothoraces

Primary spontaneous pneumothoraces are thought to result from rupture of apical pleural blebs beneath the visceral pleura, which have been identified in up to 80% of affected patients on CT scan and 90% at thoracoscopy [2] compared to only 20% of control subjects. The blebs have no epithelial lining and result from rupture of the alveolar wall.

Classically, the patient is a tall, thin male aged 20-30 years old, with increased negative pressure shear forces at the apices being implicated in sub-pleural bleb formation. Similar mechanisms may account for the predisposition of patients with Marfan’s or Marfanoid habitus to this condition.

Smoking is associated with a 12% increased risk of developing pneumothorax in otherwise healthy men [1]. Female smokers have an overall 8 fold increase in risk. Genetic factors have been identified in a small number of familial clusters.

Secondary Spontaneous pneumothorax

Secondary spontaneous pneumothoraces are less common and account for approximately 10-20% of all spontaneous pneumothoraces.

The classic presentation would be that of a patient with COPD aged 60–70 years old. However, many other causes exist.

Other causes

Recognised causes of a secondary pneumothorax (This list is not considered comprehensive)

Obstructive airway disease

  • Asthma
  • COPD

Lung and pleural malignancy


  • Pneumonia (particularly pneumocystis jiroveci [formerly PCP])
  • TB

Suppurative lung disease

  • Cystic Fibrosis
  • Bronchiectasis
  • Lung abscess

Interstitial lung disease

  • Sarcoidosis
  • Idiopathic Pulmonary Fibrosis
  • Hypersensitivity pneumonitis
  • Pneumoconiosis

Approximately 1-2% of HIV infected patients and 5-10% of patients with pneumocystis jiroveci (formerly PCP) develop a pneumothorax. With more effective treatment this incidence is falling.


A cause specific to women is catamenial pneumothorax.

A catamenial pneumothorax occurs at the time of (or within 72 hours of) menstruation.

The cause is endometriosis, which has been reported to account for approximately 5% of pneumothoraces in women [3].

Typically, the female patient will be aged 30-40 years old, the right lung will be affected (over 90% cases) and she will have been previously diagnosed with pelvic endometriosis (approximately one-third of cases). Half of these patients will have a recurrence of the pneumothorax in the following 12 months.

Hormonal treatment may improve the prognosis but given the high recurrence rate, referral for further investigation and consideration of surgery is warranted.

Primary and Secondary Pneumothoraces Compared

The table below provides a comparison between primary and secondary pneumothoraces.

Table: Comparison of primary and secondary pneumothoraces 
Primary Secondary
Peak incidence age (years) 20-30 60-70
Male:frmale ratio 6:1 3:1
Aetiology Ruptured sub-pleural bleb Various
Proportion of all spontaneous pneumothoraces 80-90% 10-20%
1 year recurrence rate (without pleurodesis) 25% Higher but dependent on underlying condition

Primary Pneumothoraces

The classic presentation is that of sudden onset pleuritic chest pain and dyspnoea.

The symptoms do not correlate closely with the size of the pneumothorax. In many cases, the symptoms are mild and approximately half of patients will present after more than 2 days of symptoms. Onset is not usually associated with physical exertion.

Secondary Pneumothoraces

The symptoms of a secondary spontaneous pneumothorax are often more severe than those associated with a primary pneumothorax because lung function may already have been compromised by the underlying pathological process.

The symptoms will vary depending on the cause. Still, the primary complaint is that of breathlessness which is often out of proportion to the size of the pneumothorax radiologically.

Unlike symptoms, the examination findings in primary spontaneous pneumothoraces are affected by the size of the pneumothorax. A small pneumothorax can be impossible to identify on clinical examination. If the pneumothorax is large, some of the features listed below may be present.

Possible clinical findings in a patient with a large spontaneous pneumothorax:

  • Tachycardia
  • Tachypnoea
  • Reduced breath sounds on the affected side
  • Reduced chest expansion on the affected
  • Hyper-resonance on the affected side
  • Decreased tactile/vocal fremitus on the affected side

The diagnosis is usually confirmed radiologically, following which specific information should be sought in order to guide management, advice and appropriate patient disposition/follow-up.

Patient information to guide management

Information required for planning management and follow up for a patient with a spontaneous pneumothorax*

  • Age of the patient
  • Does the patient feel breathless?
  • Determine if the pneumothorax is primary or secondary by reviewing the patient’s:
    • Past medical history and medication
    • History of presenting complaint (specifically ask about trauma)
    • Chest radiograph
  • History of previous pneumothorax (side, size and treatment)
  • Classify the size of the pneumothorax from the chest radiograph
    • <2 cm
    • >2 cm as measured from the lung margin to the chest wall at the level of the hilum or apex.
  • Duration of symptoms
  • Smoker (and how many cigarettes they smoke per day)
  • Family history of pneumothorax
  • Vocation
  • Plans for holidays/hobbies involving flying or SCUBA diving
  • Currently menstruating?

*This list is a guide and not considered comprehensive. Treatment may need to precede history if the patient is unstable.

Tension Pneumothorax

If the pleural leak exerts a one-way valve effect then a tension pneumothorax can develop. The recognition and management of this complication is discussed later in the session.

Radiograph Investigations

The most useful investigation is the erect PA chest radiograph despite the fact that it tends to under-estimate the size of a pneumothorax by virtue of it being a 2-dimensional image of a 3-dimensional structure.

Historically, pneumothoraces were described in subjective terms, such as ‘small rim’, ‘moderate’ and ‘halfway to the heart border’. In 2023 the British Thoracic Society (BTS) advised that with pneumothorax of sufficient size intervention depends on clinical context but, in general, usually ≥ 2cm laterally or apically on CXR, or any size on CT scan which can be safely accessed with radiological examination.

The rationale for using 2 cm as the cut-off for indicating a large pneumothorax is that this approximates the point at which up to half of the lung volume has been lost.

Guidance from The American College of Chest Physicians

The American College of Chest Physicians (ACCP) advocate measuring the apex-to-copula distance and judges any distance greater than 3 cm to represent a large pneumothorax. The use of a fixed landmark, the cupola (apex of the dome of the thoracic cavity) offered a more reproducible measurement for clinicians in comparison to the rather vague ‘lung edge to chest wall’ 2003 recommendation of the BTS. However, the 2023 BTS guidelines clarified the measurement at the level of both hilum and apex, usually ≥ 2cm laterally or apically on CXR.


Drawing a distinction between large and small pneumothoraces helps facilitate clinical decision making. Tools that quantitatively calculate pneumothorax percentage from PA radiographs are less useful clinically but may be employed in research.

A PA chest x-ray is the baseline investigation for identifying pneumothorax. The diagnosis is made by visualising the visceral pleura (lung edge) separated from the thoracic cage with no visible lung marking between the two. Small pleural effusions are seen in up to 50% of cases.

If clinical suspicion is high, and the PA radiograph is equivocal, a lateral decubitus film demonstrating a visceral pleural line in the retrosternal position or overlying the vertebrae, parallel to the chest wall, may identify occult pneumothoraces in a small number of cases.

However, the increased availability and sensitivity of CT has led to requests for lateral views becoming increasingly rare.

The main indication for performing additional views would be where a secondary pneumothorax is suspected as identification of even a small pneumothorax in this setting may significantly influence management. Expiratory films add little to the PA radiograph and are not routinely recommended.

Pneumothorax Mimics

The PA radiograph has a sensitivity of ~80-85% at identifying small pneumothoraces [17]. The diagnosis is made by the visualising the visceral pleura (lung edge) separated from the thoracic cage with no visible lung marking between the two. Small pleural effusions are sometimes seen.

The following are recognised as potential mimics of pneumothoraces [8]:

  • Medial border of the scapula
  • The outline of the oxygen reservoir bag or associated tubing
  • Clothing
  • Bedsheets
  • Companion shadows (visible subcostal groove usually ribs 1 and 2)
  • Skin folds
  • Post-pleurectomy scarring/suture material

If there is a presence of lung markings beyond the line in question, repeating the films with possible artefacts removed or comparison to previous films usually clarifies the situation.

Other Investigations

In addition to the PA chest radiograph, there are a number of other investigations available [9].


CT is considered the gold standard for identifying pneumothoraces but the radiation exposure is only justified in cases where radiographs are difficult to interpret or specific drain placement is required e.g. bullous lung disease, loculated pneumothoraces, surgical emphysema.


Ultrasounds show promise with reports of sensitivities at identifying pneumothoraces in trauma and post procedure (e.g. lung biopsy) patients of ~95%. However, it is highly user dependent and for patients with suspected spontaneous pneumothoraces, radiography has the advantage of identifying unexpected causes of pleuritic pain e.g. infection, carcinoma. Having said this, with the increasing use of ultrasound in Emergency Medicine, in the hands of an experienced user it can now reliably detect pneumothorax better than an anteroposterior chest radiograph.

Arterial gas monitoring

Arterial gas monitoring may demonstrate hypoxia but the information gained is unlikely to alter the management plan. An exception is when supplemental oxygen is being administered to patients with pneumothoraces secondary to COPD.


Management depends upon:

  • Whether the patient is symptomatic
  • Whether the pneumothorax is primary or secondary
  • The size of the pneumothorax on the PA radiograph

The guidance below is based on the BTS guidelines (2023). Different guidelines have been adopted by other international bodies [21].

Symptomatic patients and those admitted for observation should have high-flow oxygen administered (15 L/min via a non re-breathe mask with a reservoir). Inhalation of high concentrations of oxygen reduces the total pressure of gases in pleural capillaries by lowering the partial pressure of nitrogen (Henry’s Law). This increases the pressure gradient between the pleural cavity and pleural capillaries and results in increased absorption of air from the pleural cavity. Compared to breathing room air, a pneumothorax will resolve four times faster if the patient is on high-flow oxygen [11]. For patients with COPD, fixed concentration oxygen should be administered.

Learning bite

A pneumothorax will resolve up to four times faster if high flow oxygen is administered.
Entonox® diffuses into air spaces and can convert an uncomplicated pneumothorax into a tension pneumothorax. It should not be used for analgesia in this setting.

Minimal Symptoms

Patients with small spontaneous primary pneumothoraces and minimal symptoms (80% of whom will have no ongoing air leak) can be discharged with written advice and organised follow-up.

Without supplemental oxygenation, spontaneous pneumothoraces resolve at a rate of approximately 2% of the hemi-thorax volume per day [12,13].

A 1 cm pneumothorax (~15% pneumothorax) would be expected to fully resolve in approximately 10 days.

A 2 cm pneumothorax (~30-50% pneumothorax) may take 2-3 weeks to fully resolve.

Patients with spontaneous secondary pneumothoraces less than 1 cm in size and minimal symptoms do not require drainage in the emergency department but should be admitted for observation and supplemental oxygenation.

Learning bite

Never discharge a patient from the Emergency Department with a diagnosis of a secondary pneumothorax. As a minimum, supplemental oxygen and a 24 hour observation period is recommended.

Spontaneous Pneumothorax with Significant Symptoms

Primary and secondary pneumothoraxes require intervention as breathlessness reflects the risk of tension pneumothorax.

The 2023 BTS guidelines combined the management of patients with primary and secondary pneumothoraxes into a single algorithm. These guidelines categorise patients aged over 50 with significant smoking histories as having secondary pneumothoraxes.

Learning bite

Patients aged over 50 with significant smoking histories should be managed as though their pneumothorax is secondary in origin.

Pneumothorax Pathway [21]


Simple (needle) aspiration

Needle aspiration is a technique that allows aspiration of air via the chest wall without insertion of a chest drain (thoracostomy tube).


Overall, for primary spontaneous pneumothoraces, the initial success rate of the procedure is no different to that of chest drainage (60-70%). Successful aspiration is associated with a much higher likelihood of discharge than chest drain insertion and fewer complications have been reported.

Following successful aspiration, patients with primary pneumothoraces should have a short period of observation in the ED before discharge.

Recurrence rates are similar at 7 days and 1 year compared to thoracostomy tube insertion. [14]

Needle aspiration is no longer recommended for secondary pneumothorax as per 2023 BTS guidelines. [21]

BTS Guidelines

The BTS guidelines recommend use of a cannula no greater than 16G in diameter for aspiration though evidence that larger cannulae are more likely to cause a persistent pleural leak is limited. It should be remembered that narrower cannulae are also shorter and may not be long enough to reach the thoracic cavity in larger patients.

Insertion point

Insertion point for needle aspiration


The insertion point is the 2nd intercostal space in the mid-clavicular line. The second intercostal space is found by locating the end of the 2nd rib medially where it attaches at the manubrio-sternal angle. The rib space below the 2nd rib is the 2nd intercostal space. An alternative site is in the ‘safe triangle’. We describe this on the next page.


  • Inform the patient about the planned procedure and obtain written consent
  • Position the patient in a slightly reclined position
  • Identify the insertion point (mid-clavicular line in the 2nd intercostal space) and mark with a pen
  • Put on a gown and sterile gloves, clean the area with antiseptic solution and apply drapes
  • Using an aseptic technique, infiltrate a few millilitres of 1% lidocaine subcutaneously
  • Insert a commercially available kit or a size 14g cannula (attached to a 10 ml syringe containing sterile normal saline) through the chest wall at the insertion point, in a horizontal plane.
  • Aspiration of air confirms correct placement
  • Remove the trochar
  • Attach the cannula to a short connecting piece of tubing and a 3-way connector
  • Aspirate via a 50 ml syringe, turn the tap and dispel the air into the atmosphere
  • Turn the tap again and aspirate another 50 ml from the pleural cavity
  • Continue until the patient coughs, 2.5 litres have been aspirated or no more air can be aspirated
  • Repeat the chest radiograph
  • If the procedure is successful, the cannula should be removed and a small occlusive dressing placed over the insertion site
  • If the procedure is unsuccessful proceed to insertion of a thoracostomy tube.

Needle Aspiration of Pneumothorax by the NEJM (Video) [16]

Key points

  • Failure to attach the cannula to a connecting piece of tubing increases the likelihood of tube kinking or ‘accidental removal’
  • A minimum of two persons are required for this procedure, one to manually secure the cannula and turn the connector, the other to perform the aspiration
  • This is a time consuming procedure (50 times x 50 ml) but success rates are relatively high
  • Beware of turning the tap the wrong way and inserting air into the pleural cavity
  • The syringe gets very warm from the friction and increasing effort is required with each aspiration.

Intercostal Chest Drain (Thoracostomy Tube)

Historically, the treatment for a large pneumothorax was insertion of a large drain (e.g. 28FG) through an incision in the chest wall.

During the last decade there has been a move towards inserting smaller drains percutaneously. Small drains (e.g. 8-14FG) have been shown to be associated with fewer complications (particularly subcutaneous emphysema) without prolonging time to resolution [17].

Small drains may be associated with a higher failure rate when draining very large pneumothoraces but currently this evidence is limited. In obese patients, the Seldinger technique may not be technically possible as the needle may be too short to traverse the chest wall. Whichever technique is used, insertion in the ‘safe triangle’ attempts to avoid injury to the long thoracic nerve and lateral thoracic artery, which sit in the mid-axillary line.

Safe Triangle

The triangle is formed by the anterior border of latissimus dorsi posteriorly, the lateral aspect of pectoralis major anteriorly, and the 6th rib inferiorly forming an apex below the axilla. In young, thin males the nipple will lie in the 5th intercostal space. Insertion of the drain just above the underlying rib minimises the risk of injury to the intercostal bundle.

Seldinger technique

  • Inform the patient about the planned procedure and obtain written consent
  • Position the patient reclined at approximately 45 degrees with their hand placed behind their head
  • Identify the insertion point (just anterior to the mid-axillary line in the 5th intercostal space) and mark the with a pen
  • Put on a gown and sterile gloves, clean the area with anti-septic solution and apply drapes
  • Using an aseptic technique, infiltrate 1% lidocaine (maximum 0.3mls/kg of 1% lidocaine) subcutaneously and down to the pleura
  • Insert the needle from the drain kit (attached to the provided syringe) slowly through the chest wall, just above the underlying rib, in a horizontal plane
  • Stop advancing the aspiration needle when aspiration of air confirms correct placement
  • Thread the guidewire through the needle
  • Remove the aspiration needle
  • Gently dilate the track with the dilators provided (sometimes a small nick needs to be made in the skin with a scalpel to facilitate this)
  • Feed the drain over the guide wire (usually to about 12 cm in adults)
  • Remove the guidewire and the tube obturator
  • Fogging of the tube suggests correct placement
  • Connect the tube to an underwater drainage system (below the level of the patient). An assistant should hold the drain at this stage to prevent the drain coming out before suturing
  • Bubbling on patient coughing and a fluid swing confirms drain placement
  • Secure with a stay suture (BTS guidance)
  • Place a clear dressing over the insertion site
  • Secure the drain to the chest wall with an ‘omental tag‘ (BTS guidance)
  • Repeat the chest radiograph


During the procedure, holding the dilators close to the chest wall should prevent excessive force of insertion or ‘a sudden give’. These are solid objects and on the left side the apex of the heart lie close to the insertion point. The BTS cautions that the dilator should not be inserted more than 1 cm deep to the skin.

Seldinger drain kit contents



Both techniques are low- risk in experienced hands. However, the National Patient Safety Agency has issued specific recommendations following reports of 12 deaths and 15 cases of serious harm associated with drain insertion between 2005 and 2008, most attributed to the dilator/trochar [18].

Recognised complications include:

  • Drain blockage (8.1%)
  • Malposition (0.6%)
  • Empyema (0.2%)
  • Injury (0.2%) – visceral (lung, heart, liver, spleen), nerve (intercostal, long thoracic or sympathetic (Horner’s syndrome)), artery (lateral thoracic, internal mammary)
  • Re-expansion pulmonary oedema R.P.O 0.6%

Learning bite

Chest drain insertion is potentially dangerous.
Twenty seven cases of death or serious harm were reported as a result of chest drain insertion in the UK between 2005 and 2008. This is probably a conservative figure. This procedure should only be performed by a person trained and signed off as competent to do so.

Tension Pneumothorax: Introduction

The incidence of tension pneumothoraces resulting from primary and secondary spontaneous pneumothoraces is unknown, but many case reports have been published, exceeding reports of those associated with trauma. However, it is likely that the latter are significantly under-reported.

Traditional teaching has described a tension pneumothorax as an expanding pneumothorax resulting from a one-way valve effect of a pleural breach, which results in hyper-resonance on the affected side, mediastinal shift (deviated trachea) and reduced cardiac output (hypotension) secondary to kinking of the great vessels. The risk of death whilst awaiting a chest radiograph has been considered so high that decompression with a cannula (2nd intercostal space in the mid-clavicular line) has been advocated if the diagnosis is even considered and a radiograph demonstrating a tension pneumothorax is one that ‘should not have been done’.

Leigh-Smith and Harris have challenged the historically taught classical presentation and management of a tension pneumothorax [19]. Chest pain, respiratory distress, tachycardia and reduced air entry on the side of the tension pneumothorax are commonly present. Conversely, tracheal deviation, hypotension, neck vein distension and hyper-resonance are the exception rather than the rule (<25% cases) and when present represent the more extreme end of the spectrum associated with imminent arrest [20]. In spontaneous tension pneumothoraces, respiratory arrest from hypoxia usually precedes cardiac arrest [19].

Fig 1: The never event – a chest radiograph demonstrating a tension pneumothorax

Learning bite

Less than 25% of cases will have the ‘classical features’ of neck vein distension, tracheal deviation, hyper-resonance and cardiovascular instability.

Tension Pneumothorax: Management

In view of the fact that clinical signs may differ little from a pneumothorax that is not under tension, it is recommended that stable patients in the ED should have urgent chest radiographs performed in the resuscitation room rather than undergoing ‘blind emergency needle decompression’, which is not without complication.

Mediastinal shift may be seen in severe cases, but the most common radiological feature found with tension pneumothoraces is widened rib spaces and a flattened hemi-diaphragm on the affected side. Leigh-Smith and Harris have proposed the following criteria for when decompression of a suspected pneumothorax should be performed before an urgent radiograph [19].

  • SpO2< 92% on O2
  • Systolic BP< 90 mmHg
  • Respiratory rate <10
  • Decreased level of consciousness on O2
  • Cardiac arrest

Finally, the potentially catastrophic belief that the ‘absence of a hiss’ on needle decompression rules out a tension pneumothorax has been categorically shown to be false. Although presence of a hiss and clinical improvement almost certainly confirms the diagnosis, the absence of a hiss may be due to the cannula being too short, kinked or blocked. Studies on trauma patients (though not directly comparable) have found that a 14g cannula placed in the second intercostal space would be too short to penetrate the parietal pleura in up to one-third of patients. This method can be quick and effective but failure of decompression in a peri-arrest patient should be followed by creating an open thoracostomy in the 5th intercostal space.

Learning bite

‘Absence of a hiss’ does not exclude a tension pneumothorax. The cannula may be too short, kinked or blocked.

Referral to a respiratory specialist

The BTS recommends that patients admitted with a pneumothorax should be referred to a respiratory physician within 24 hours.

Chest drain suction

The routine use of suction is not recommended.

Chest drain suction (high volume, low pressure) should be considered when lung re-expansion has not occurred 48 hours after chest drain insertion.

Failure of the lung to re-expand after chest drain insertion is suggestive of an ongoing air leak. Earlier application of suction is not recommended because of concerns over precipitating re-expansion pulmonary oedema, which conveys a significant mortality risk. The lung capillaries become ‘leaky’ following a pneumothorax and application of additional mechanical stresses can result in oedema.

There is often no ongoing air leak in spontaneous pneumothoraces and lower mechanical stresses will be caused by aspiration or thoracostomy tube insertion without suction. Re-expansion pulmonary oedema is more common in patients under 30 years old, those with late presentation of a pneumothorax and those with large pneumothoraces.

Referral to a cardiothoracic surgeon

The following criteria are accepted as indications for seeking a cardiothoracic opinion:

  • Second ipsilateral pneumothorax
  • First contra-lateral pneumothorax
  • Bilateral spontaneous pneumothorax
  • Persistent air leak or failure of lung re-expansion 5 days after chest drain insertion
  • Spontaneous haemothorax
  • Professions at risk (e.g. pilots, divers)
  • Pregnancy

The risk of pneumothorax recurrence increases in pregnancy and conveys a significant risk to both mother and foetus.

Most air leaks will resolve after two weeks but the risk of infection of prolonged drainage may outweigh the low morbidity rate associated with surgical intervention, which has the added benefit of significantly reducing the future recurrence rate.

Learning bite

A second pneumothorax, whether ipsilateral or contralateral, is an indication for referral to a thoracic surgeon.

Surgical options include:

  • Open thoracotomy, resection of pleural blebs and pleurectomy: This is considered the gold standard in preventing recurrences, with a failure rate of less than 1%
  • Open thoracotomy, resection of pleural blebs and pleural abrasion/pleurodesis: The recurrence rate is approximately 2%
  • Video assisted thorascopic surgery (VATS):This technique is becoming increasingly popular as it is associated with a shorter hospital stay and less postoperative pain. The recurrence rates of >5% mean that it cannot be recommended for patients wishing to dive
  • Chemical pleurodesis: This is an option for patients that refuse surgery or are considered poor surgical candidates. Tetracycline, or talc, can be administered via the chest drain. The failure rate is approximately 10%.


Follow up

Patients discharged from the ED following a spontaneous pneumothorax should ideally be reviewed by a respiratory physician after 2 weeks. In practice, it may be impossible to access specialist clinics in the recommended timeframe. If this is the case, then the patient should be advised to initially return to the ED, at 2 weeks, for a repeat chest radiograph and senior doctor review pending specialist review.

If the pneumothorax is recurrent, or the patient has a high risk vocation, referral for a cardiothoracic outpatient appointment is appropriate.


All patients discharged following a pneumothorax should be given verbal and written advice to immediately return to the ED should they become breathless.

Other advice should also be given on the following:


Smokers should be advised to quit and seek assistance from their GP to successfully achieve this.

Learning bite

Men who smoke more than 20 cigarettes a day have 100 times the risk of developing a pneumothorax compared to men that don’t smoke.


Changes in atmospheric pressure can rapidly convert simple pneumothoraces to tension pneumothoraces with catastrophic consequences. The BTS Air Travel Working Party recommends that patients should be advised to avoid flying for at least a week after a chest radiograph has confirmed complete resolution of their spontaneous pneumothorax, or until they have recovered from a definitive surgical procedure aimed to prevent pneumothorax recurrence. The previous advice to avoid flying for 6 weeks is not supported by existing evidence. It is advised that 2 weeks should have elapsed following confirmed resolution if the pneumothorax was traumatic in origin, which corresponds to the advice issued by the UK Civil Aviation Authority.

Learning bite

Patients should be advised to avoid flying for at least a week after a chest radiograph has confirmed complete resolution of their spontaneous pneumothorax.


The British Thoracic Society Fitness to Dive Group recommends that underwater diving should be permanently avoided after a pneumothorax, unless the patient has had bilateral open surgical pleurectomy.

Learning bite

Underwater diving should be permanently avoided after a pneumothorax, unless the patient has had bilateral open surgical pleurectomy.

There are a number of pitfalls that can occur during treatment of pneumothoraces:

  • Failure to identify a pneumothorax as secondary and thus following the wrong BTS management algorithm
  • Discharging a patient with a secondary pneumothorax from the ED
  • Belief that ‘the absence of a hiss’ on attempted needle decompression excludes a tension pneumothorax
  • Use of excessive force when inserting track dilators and chest drains
  • Insertion of chest drains outside of the ‘safe triangle‘
  • Failure to give patients advice on smoking cessation
  • Failure to advise patients against flying and diving
  • Failure to organise review of discharged patients
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