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.