11. Pneumothorax

Question 1

what is pneumothorax

Answer 1

air in pleural space

Question 2

what are the different causes of pneumothorax

Answer 2

Air from lung: 1. primary spontaneous - most common in young, tall thin males. Most cases thought to involve rupture of small subpleural bulla (air-filled sac) 2. secondary spontaneous - underlying lung problem that increases pressure in lung or weakens lung wall, eg COPD, asthma, bronchiectasis 3. iatrogenic (e.g. high pressure ventilation) Air through chest wall 1. trauma 2. iatrogenic (e.g. insertion of CVP line in neck, fine needle aspiration of breast)

Question 3

what is a tension pneumothorax

Answer 3

any size of pneumothorax causing mediastinal shift and cardiovascular collapse

Question 4

what causes a pneumothorax to be “tension”

Answer 4

i. development of one way valve that allows air entry into pleural space on inspiration but not air exit on expiration… ii. increase intrapleural pressure… iii. mediastinal shift and kinking of cardiac vessels… iv. decresaed venous return and cardiac output… v. hypoxaemia and haemodynamic compromise… vi. death

Question 5

name 2 symptoms of pneumothorax

Answer 5

1. acute onset dyspnoea 2. acute onset pleuritic chest pain

Question 6

name 3 signs of pneumothorax

Answer 6

1. hyper-resonance on percussion 2. decreased chest wall movement 3. decreased breath sounds on auscultation

Question 7

which additional signs/symptoms suggest tension pneumothorax

Answer 7

• resp. distress / tachypnoea - tachycardia / hypotension - tracheal shift

Question 8

how should pneumothorax be managed

Answer 8

1. cannula insertion: 2nd IC space mid-clavicular line 2. chest drain: 5th IC space mid-axillary line

Question 9

is this a pneumothorax or tension pneumothorax - explain why

Answer 9

pneumothorax:

• visible pleural edge
• lung markings not visible beyond this point

(but no mediastinal shift)

Question 10

is this a pneumothorax or tension pneumothorax - explain why

Answer 10

tension pneumothorax

• visible pleural edge
• lung markings not visible beyond this point
• • mediastinal shift away from pneumothorax