Pneumothorax

Question 1

Risk factors and causes for pneumothorax

Answer 1

Pre-existing lung disease
Connective tissue disease: Marfan’s, RA
Ventilation, inc non-invasive
?Endometriosis - can get “catamenial” pneumothorax, i.e. when menstruating

In “healthy people” - being tall + slim, smoking, being young (<40), family history

Chest trauma
Iatrogenic

Question 2

Symptoms of pneumothorax

Answer 2

Sudden onset
Dyspnoea
Pleuritic chest pain
Sweating

Question 3

Signs of pneumothorax

Answer 3

Tachypnoea
Tachycardia
Reduced expansion, hyper resonance to percussion, diminished breath sounds

Question 4

What is the difference between primary and secondary pneumothorax?

Answer 4

Primary = no underlying lung disease, trauma, or precipitating event
Secondary = underlying lung disease

Question 5

Pathogenesis of pneumothorax

Answer 5

It is often spontaneous due to rupture of sub-pleural bullae. Normally, both the alveolar pressure AND atmospheric pressure are both > intrapleural pressure

If a communication develops between an alveolus and the pleural space, or between the atmosphere and the pleural space, gases will follow the pressure gradient and flow into the pleural space.
The thoracic cavity enlarges and the lung becomes smaller.

Question 6

What is pneumothorax?

Answer 6

Gas within the pleural space

Question 7

Causes of iatrogenic pneumothorax?

Answer 7

CVP line insertion, pleural aspiration/biopsy, transbronchial biopsy, liver biopsy, positive pressure ventilation

Question 8

Investigations to confirm diagnosis

Answer 8

Chest radiography
CT chest - used if multiple traumatic injuries, can be useful if underlying resp disease
Chest USS - used in blunt trauma victims
Bronchoscopy

Question 9

Management of primary pneumothorax

Answer 9

If the rim of air is < 2cm and the patient is not short of breath - consider conservative management + discharge

If rim of air >2cm - aspiration, if fails then a chest drain should be inserted

Question 10

Management of secondary pneumothorax

Answer 10

ADMIT ALL FOR AT LEAST 24 HOURS

Chest drain if:
- >50yo
AND Rim of air >2cm
AND/OR SOB

Otherwise and rim of air between 1-2 = aspiration, if fails then insert chest drain

If <1cm, give oxygen and admit for 24 hours.

Question 11

Location for needle aspiration

Answer 11

2nd intercostal space, midclavicular line

Question 12

Chest drain insertion anatomy - ‘safe triangle’

Answer 12

Mid axillary line of the 5th intercostal space.

Bordered by:

• Anterior edge latissimus dorsi
• Lateral border of pectoralis major
• 5th intercostal space
• The apex below the axilla

Question 13

Recurrence rate of pneumothorax

Answer 13

30-50% in primary and even higher in secondary

Question 14

Activities to avoid in young patient with simple pneumothorax

Answer 14

Smoking

Scuba diving

Question 15

Symptoms/signs of tension pneumothorax

Answer 15

Sudden onset of dyspnoea and/or pleuritic chest pain
Reduced expansion, hyper-resonance to percussion, diminished breath sounds on the affected side, trachea deviated away from the affected side, respiratory distress, tachycardia, hypotension, distended neck veins.

Question 16

Explain pathophys of tension pneumothorax

Answer 16

Intrapleural pressure exceeds atmospheric pressure +
results ina ball valve (one way) mechanism that promotes inspiratory accumulation of pleural gases.
The build-up of pressure within the pleural space eventually results in hypoxemia and respiratory failure from compression of the lung. The mediastinum is pushed over into the contralateral hemithorax, kinking and compressing the great veins. Unless the air is rapidly removed, cardiorespiratory arrest will occur.

Question 17

Emergency management of tension pneumothorax

Answer 17

To remove the air, insert a large-bore (14-16G) needle with a syringe, partially filled with 0.9% saline, into the 2nd intercostal space in the midclavicular line. Remove plunger to allow the trapped air to bubble through the syringe until a chest tube can be placed. Alternatively, insert a large-bore Venflon in the same location. –> NEEDLE DECOMPRESSION AND CHEST TUBE INSERTION

Do this BEFORE requesting a CXR.

Insert a chest drain afterwards.