Lecture 16: Pneumothorax and pleural effusion

Question 1

What is a pneumothorax?

Answer 1

Air within the pleural cavity
-if you get a disruption of the pleura, air flows from a higher pressure outside the chest, to the negative pressure in pleural cavity
=lung collapse

Question 2

What is the difference between simple and tension pneumothorax?

Answer 2

Simple: rim of air in the pleural cavity which doesn’t cause any impairment (haemodynamically stable patients)

Tension: hypotensive, tachycardic, causes haemodynamic instability. Caused by one way flow of air

Question 3

What is the difference between primary and secondary pneumothorax?

Answer 3

Primary: no underlying lung pathology
Risk factors- male, young, family history of pneumothorax, smoking

Secondary: underlying lung pathology e.g. COPD, asthma, bronchiectasis, lung cancer, infections, RA

Question 4

What are the causes of pneumothorax?

Answer 4

Spontaneous- due to subpleural blebs/bulla bursting (air filled sacs)
Iatrogenic- insertion of central lines/pacing wires
Trauma- severe chest wall injury (stab/gunshot), rib fractures (puncture the visceralpleura)

Question 5

What are the different types of pneumothorax?

Answer 5

Tension VS Simple

• simple can be subdivided into Primary (usually spontaneous) VS Secondary
• primary and secondary can turn into tension pneumothorax

Question 6

What are the presenting symptoms and signs of simple pneumothorax?

Answer 6

• chest pain (pleuritic- breathing in you get a stabbing pain, as air rushes in irritating the pleural lining)
• sometimes SOB
• history of trauma/lung disease
• tracheal deviation normal
• chest movement reduced on affected side due to collapsed lung
• percussion is hyper-resonant on affected side
• ausciltation can’t hear breath sounds on affected side due to collapsed lung

Question 7

What are the radiological findings of a simple pneumothorax?

Answer 7

• can see collapsed lung borders
• absent lung markings
• hyper-lucent (appears darker)

Question 8

How do you treat simple pneumothorax?

Answer 8

• conservative treatment (for small pneumothorax)
• pleural aspiration (needle into cavity to drain air)
• chest drain insertion (ultrasound guided)

Question 9

How do you insert a chest drain?

Answer 9

In the safe triangle
Borders
Superior: base of axilla
Inferior: 6th rib/5th intercostal space
Anterior: lateral edge of pec major
Posterior: lateral edge of latissimus dorsi

End of chest drain is put into an underwater seal

Question 10

What is an underwater seal?

Answer 10

Exhales
-air leaves and comes out as bubbles and leaves the bag to open air
Inhales
-negative pressure inside pleural cavity, the water level rise, this prevents air entering

Question 11

How does a tension pneumothorax occur?

Answer 11

• when patient exhales, the air doesn’t leave, as the pleural lining acts as a valve and allows only a one way flow of air
• causes a build up of air
• compress on IVC/SVC which reduces blood flow to heart= tachycardic, low bp, cyanotic, hypoxaemic

Question 12

What are the presenting signs and symptoms of a tension pneumothorax?

Answer 12

Similar to simple pneumothorax, but also:

• respiratory distress
• cyanosis
• marked tachycardia
• marked hypoxaemia

Tracheal deviation- away from affected side
Chest movement- reduced on affected side
Auscultation- absent on affected side due to collapsed lung
No time to do percussion/resonance findings

Question 13

How do you treat a tension pneumothorax?

Answer 13

Emergency needle decompression

-second intercostal space in the mid-clavicular line

Question 14

Where does the first rib lie?

Answer 14

Just below the clavicle

Question 15

What is a pleural effusion?

Answer 15

Excess fluid in the pleural cavity (imbalance between rate of production from systemic capillaries and absorption via lymphatic system)

Question 16

What is a simple effusion?

Answer 16

When the fluid is pleural fluid (can be transudate/exudate)

Question 17

What other fluids can fill the pleural cavity?

Answer 17

Haemothorax: blood e.g. trauma
Chylothorax: lymph
Empyema: pus e.g. secondary to resistant infection

Question 18

What are the presenting signs and symptoms of a pleural effusion?

Answer 18

• SOB gradual onset
• pleuritic chest pain due to irritation of pleural lining

Tracheal deviation: away from affected side (only on a large pleural effusion)
Chest movement: reduced on affected side
Percussion: ‘stony’/dull on affected side
Breath sounds: reduced/absent on affected side
Vocal resonance: reduced on affected side

Question 19

What do you see upon radiological findings for a pleural effusion?

Answer 19

Meniscal line- top of fluid line

Question 20

What causes simple effusion?

Answer 20

Transudate:
-congestive cardiac failure
-hypoproteinaemia (fluid leaves capillaries): nephrotic syndrome/liver cirrhosis
Exudate:
-infection (TB/pneumonia)
-lung malignancy
-pulmonary infarction

Question 21

What causes haemothorax and chylothorax?

Answer 21

Trauma

Question 22

How do you further investigate a simple pleural effusion?

Answer 22

Pleural aspiration using ultrasound

-send fluid off for protein/glucose levels, LDH (lactate dehydrogenase), pH, gram stain

Question 23

How do we figure out whether the fluid in a simple effusion is transudate or exudate?

Answer 23

Light's criteria
Transudate:
-not many protein molecules
Exudate:
-lots of protein molecules passing through capillaries

Question 24

How do you treat pleural effusion?

Answer 24

Depends on cause

• in very symptomatic patients, chest aspiration may be needed
• recurrent effusions may require: IPC (indwelling pleural catheter for intermittent drainage), pleurodesis (obliteration of pleural cavity)