INSTRUCTION

Examine this patient's chest.

SALIENT FEATURES

History

· Sudden onset or rapidly progressive dyspnoea.

· Ipsilateral acute pleuritic pain - the pain is either sharp or a steady ache.

· A small pneumothorax may be asymptomatic.

· Obtain history of recent pleural aspiration or insertion of subclavian line (J R Soc Med 1997: 90: 319-21), recent surgery to

head and neck, abdominal procedures using bowel or peritoneal distension.

· History of asthma, COAD, ARDS, pneumonia, trauma to chest.

· History of Marfan's syndrome.

· History of HIV.

· History of positive pressure ventilation.

Examination

· Decreased movement of the affected side.

· Increased percussion note.

· Trachea may be central (small pneumothorax) or deviated to the affected side (underlying collapse of lung) or the opposite side

(large pneumothorax).

· Increased vocal resonance with diminished breath sounds.

Proceed as follows:

· Look for clues regarding aetiology:

-Pleural aspiration site.

-Infraclavicular region for a bruise from the central line.

-Comment if the patient is thin or has marfanoid features.

Inhaler or peak flow meter by the bedside (asthma, COAD).

· Tell the examiner that you would suspect tension pneumothorax when there is tachycardia (>135 beats/minute), hypotension

and pulsus paradoxus.

DIAGNOSIS

This patient has diminished breath sounds and hyper-resonant note on R/L side of the chest (lesion) due to pneumothorax

secondary to Marfan's syndrome (aetiology), and is not breathless at rest (functional status).

Read recent review: N Engl J Med 2000; 342: 868-74.

QUESTIONS

What do you understand by the term 'pneumothorax'?

Air in the pleural cavity.

How would you investigate this patient?

· CXR, both inspiratory and expiratory phases. In critically ill patients pneumo-thorax is suspected when (a) the costophrenic

angle extends more inferiorly than usual due to air- the 'deep sulcus sign' (Radiology 1980; 136: 25-7), (b) liver appears more

radiolucent due to air in the CP angle, or on the left side, when the air will outline the medial aspect of the hemidiaphragm

under the heart.

· Blood gases if the patient is breathless: hypoxaemia depending on the shunting,

whereas hypercapnia does not develop.

ADVANCED-LEVEL QUESTIONS

How would you grade the degree of collapse?

British Thoracic Society grading:

· Small: where there is a small rim of air around the lung.

· Moderate: when the lung is collapsed towards the heart border.

· Complete: airless lung, separate from the diaphragm (aspiration is necessary).

· Tension: any pneumothorax with cardiorespiratory distress (rare and requires immediate

drainage).

How would you manage this patient?

· Small pneumothoraces (less than 20% in size) spontaneously resolve within

weeks.

· Larger ones (irrespective of size) with normal lungs are managed by simple aspir-ation rather than an intercostal tube as the

initial drainage procedure. Aspiration is less painful than intercostal drainage, leads to a shorter admission and reduces the

need for pleurectomy with no increase in recurrence rate at 1 year.

· When there is rapid re-expansion following simple aspiration, an intercostal tube with underwater seal drainage is used. The

tube should be left in for at least 24 hours. When the lung re-expands, clamp the tube for 24 hours. If repeat radio-graphy

shows that the lung remains expanded, the tube can be removed. If not, suction should be applied to the tube. If it fails to

resolve within I week, surgical pleurodesis should be considered. Video-assisted thoracoscopic surgery with several chest ports

allows clear visualization of the pleural cavity for resection of bullae and pleurodesis.

What are the causes of pneumothorax?

· Spontaneous (usually in thin males).

· Trauma.

· Bronchial asthma.

· COAD - emphysematous bulla (JAMA 1975; 234: 389-93).

· Carcinoma of the lung.

· Cystic fibrosis.

· TB (the original descriptions of pneumothorax were commonly associated with

TB, JAMA 1931; 96: 653-7).

· Mechanical ventilation.

· Marfan's syndrome, Ehlers-Danlos syndrome.

· Catamenial pneumothorax, i.e. pneumothorax that occurs in association with menstruation.

How would you perform a pleurodesis?

By injecting talc into the pleural cavity via the intercostal tube.

In which patients would you avoid doing a pleurodesis?

In patients with underlying cystic fibrosis. These patients may require lung trans-plantation in the future and pleurodesis may make

this procedure technically not feasible.

When would you suspect a tension pneumothorax?

Tension pneumothorax should be suspected in the presence of any of the following:

· Severe progressive dyspnoea.

· Severe tachycardia.

· Hypotension.

· Marked mediastinal shift.

When should open thoracotomy be considered?

It should be considered if one of the following is present:

· A third episode of spontaneous pneumothorax.

· Any occurrence of bilateral pneumothorax.

· Failure of the lung to expand after tube thoracostomy for the first episode.

O.K. Williamson (1866-1941), an English physician, described the Williamson sign, i.e. blood pressure in the leg is lower than that in

the upper limb on the affected side in pneumothorax.