Pleural and chest wall disease

Question 1

Complete the diagram on how the chest moves in inspiration

Answer 1

Question 2

How does expiration occur?

Answer 2

Expiration is passive

Elastic recoil

Natural elasticity of the lungs, which tend to collapse if they are not held against the thoracic wall

Question 3

How does air enter the lungs?

Answer 3

To take a breath in, the external intercostal muscles contract.

rib cage moves up and out, diaphragm moves down at the same time

negative pressure within the thoracic cavity

Lungs are held to the thoracic wall by the pleural membranes, and so when rib cage moves up and out, lungs expand outwards

Negative pressure within the lungs -> air moves in through the upper and lower airways

Question 4

What are the 2 causes of altered respiratory mechanics?

Answer 4

Chest wall (Kyphoscoliosis)

Respiratory muscle weakness

Question 5

What is the pleura?

Answer 5

The pleura is a thin tissue covered by a layer of cells (mesothelial cells) that surrounds the lungs and lines the inside of the chest wall

Question 6

What are the 2 layers of the pleura?

Answer 6

Two layers – parietal and visceral pleura. Space between these two layers is the pleural space

Two sides are completely separate

Question 7

What pressure is the pleural space and why?

Answer 7

Pleural space is normally at negative (subatmospheric) pressure

◦This keeps the lungs inflated

Question 8

What is pleural fluid and what is its role?

Answer 8

Normal pleural space only has a few mls of fluid

Helps lubricate the normal movement of the lungs during breathing

Pleural fluid forms a <1mm film

Fluid contains protein and small numbers of cells: Lymphocytes, macrophages, mesothelial cells

pH ~ 7.6

Question 9

How thick is the pleura?

Answer 9

Pleura is 0.3-0.5 mm thick

Question 10

What happens when fluid or air move into the pleural space?

Answer 10

effusion or pneumothorax

Pleural effusion – fluid in the pleural space

Pneumothorax – air in the pleural space

Question 11

What are the effects of pleural effusion/pneumothorax?

Answer 11

This accumulation of positive pressure within the pleural space leads to partial or complete collapse of the underlying lung

Question 12

What are the types of pleural effusion?

Answer 12

◦Pleural infection/Empyema

◦Malignant Pleural Effusion

◦Heart failure

◦Haemothorax

Question 13

What are the presenting features of a pneumothorax?

Answer 13

Breathless

Chest pain

Cough

History / family history

Raised respiratory rate, May have low oxygen saturations

If unwell with tension pneumothorax – may be very unwell/peri arrest

On examination: Reduced breath sounds, increased percussion note, reduced expansion, tracheal deviation

Abnormal CXR

Question 14

What does this show?

Answer 14

Pneumothorax

Question 15

What are the subtypes of pneumothorax?

Answer 15

Tension pneumothorax -> ‘one way valve’

Primary/Secondary/Traumatic/ Iatrogenic (caused by hospital)

Question 16

What is a primary spontanious pneumothorax?

Answer 16

Occurs in healthy young tall males individuals

Apical bleb

More common in smokers (especially cannabis smoking)

Tension – rarely occurs

Managed according to the size and symptoms of the patient

Won’t always need a drain or admission

Question 17

What is a secondary pneumothorax?

Answer 17

◦Background of known lung disease eg: COPD, bronchiectasis, ILD etc

◦Mostly will need a drain

◦Tension more common

Question 18

What are the possible outcomes in the BTS guidelines for manageing spontanious pneumothoraxes?

Answer 18

Discharge

Aspirate

Admit

Chest drain

Question 19

When is pleurodesis performed?

Answer 19

Primary

◦54% recurrence in the first 4 years

◦20-30% recurrence in first 2 years

◦Recurrent primary – Surgical / medical thoracoscopy and pleurodesis

Secondary

◦Attempt pleurodesis after the first episode as the recurrence rate is high

Question 20

What are the treatment options for recurrent primary pneumothorax?

Answer 20

Recurrent primary – Surgical / medical thoracoscopy and pleurodesis

Question 21

What advice is given to pneumothorax patients?

Answer 21

No deep sea diving ever ( any sudden change in pressure risk is higher)

Normal swimming and diving to less than ten feet depth is fine.

Air travel – one week after full re-expansion of the lung.

Coast guards, Naval officers, air force etc will need to change jobs.

High Altitude sports and travel should be done with caution and should be discouraged

Stop smoking

Question 22

How do pleural effusions occur?

Answer 22

Small volume of lubricating fluid is maintained via a delicate balance of hydrostatic and oncotic pressure, and lymphatic drainage

Disturbances in any of these mechanisms may lead to pathology and cause a pleural effusion

Question 23

What are the clinical features of a pleural effusion?

Answer 23

◦SOB, cough, pleuritic chest pain

◦Reduced breath sounds, “Dull” to percussion on examination

Question 24

What does this show?

Answer 24

Pleural effusion

Question 25

What are the causes of pleural effusion?

Answer 25

1. Acute Vs Chronic, Benign Vs Malignant
2. Altered permeability of the pleural membranes e.g. inflammation, infection, cancer
3. Reduced oncotic pressure (low albumin) e.g. renal disease, liver cirrhosis
4. Increased capillary hydrostatic pressure e.g. Heart failure
5. Decreased lymphatic drainage or blockage e.g. malignancy, trauma
6. Increased peritoneal fluid e.g liver cirrhosis, peritoneal dialysis
7. Commonest causes are heart failure, pneumonia and malignancy

Question 26

Name some examples of infective, benign and malignant causes of pleural effusion.

Answer 26

Infection

◦Bacterial

◦Tuberculous

◦Fungal

◦Viral

Benign

◦High oncotic pressure – heart failure, fluid overload

◦Low protein state – nephrotic syndrome, protein losing enteropathy, chronic liver disease

◦Autoimmune disease – Rheumatoid arthritis, SLE

◦Reactive-PE, Dresslers syndrome

Malignant

◦Primary - Mesothelioma

◦Secondary

• Most common – primary lung, breast. Gyneacological, heamotological, renal, GI tract

Question 27

Pleural infections are uncommon.

True or false?

Answer 27

False

Common

Question 28

• More than 30% of patients with _________ either die or require surgery.
• 20% 1 year mortality (this has been fairly consistent)

Answer 28

Pleural infection

Question 29

What are the risk factors for pleural infection?

Answer 29

◦Diabetes

◦Immunosuppression (steroids)

◦Alcohol, IVDU

◦Poor oral hygiene and aspiration (anaerobic).

◦Iatrogenic e.g. previous pleural procedure

◦Trauma

◦Recent hospitalization

Question 30

What does pleural effusion seen on CXR with systemic features of infection such as fever, raised CRP/WCC suggest?

Answer 30

Pleural infection

Question 31

How is pleural infection diagnosed?

Answer 31

Take a pleural fluid sample

Question 32

What are predictors of a worse outcome with pleural infection?

Answer 32

◦pH <7.2 High LDH

◦Low glucose (<2/3rd of serum glucose)

◦Positive culture

◦Loculations (seen on ultrasound or CT)

Question 33

What are the 3 types of parapneumonic effusions?

Answer 33

Uncomplicated parapneumonic effusion

◦Resolve on treatment of the underlying pneumonia, may not need to be drained

Complicated parapneumonic effusion

◦Bacterial invasion into the pleural space

◦Fibrin deposition may form locules/septations

◦Patient will likely need a drain

Empyema

◦Frank pus within the pleural cavity

◦May organise with thickening of the pleural surface preventing lung re-expansion and impairing lung function.

Question 34

How are patients with pleural infection managed?

Answer 34

Accurate diagnosis

Control infection

◦Choosing correct antibiotics

Drainage of infected material

◦Chest Drain (under ultrasound, with consent and when safe to do so)

◦Management of the chest drain is key!

◦The aim is to REMOVE INFECTION from the pleural space, so avoid blockages.

Question 35

Why does malignant effusion significantly impact quality of life?

Answer 35

Malignant effusion has high recurrence rate

Median life expectancy for Malignant effusion due to any cause – 6 months

Impact on wider health economy - Average LOS 4 to 6 days

Question 36

What are the clinical features of malignant effusions?

Answer 36

Mostly unilateral

Massive unilateral effusion are usually not benign

Often present with breathlessness

Cough

Hypoxia

Mostly they are hemorrhagic

Question 37

How are malignant effusions managed?

Answer 37

Minimally invasive and reduced number of interventions

Options available:

◦Aspiration – >90% recurrence rate

◦Chest drain +/- pleurodesis – 60-70% success

◦Indwelling pleural catheter

◦Thoracoscopic drainage + pleurodesis

Question 38

Why are indwelling pleural catheters the best option for malignant effusions?

Answer 38

Avoids patient admission to hospital.

Suitable for long term drainage

Improves quality of life

50% spontaneous pleurodesis

Question 39

What is talc pleurodesis?

Answer 39

Pleurodesis - sticking together pleura

‘Medicated’ talc

Creates a talc ‘slurry’ (a bit like glue) to stick the pleura together

Works in about 70%

Question 40

When is talc pleurodesis used?

Answer 40

Talc pleurodesis for Pleural Effusions (without infection)

To prevent recurrence

Question 41

What are the dangers of talc pleurodesis?

Answer 41

Lung needs to be reinflated, and output <200ml/24hr

Drain can’t be blocked! Drain needs to not fall out!

Pain, fever

Question 42

Which surgical procedures are used for pleurodesis?

Answer 42

VATS Pleurodesis

Medical Thoracoscopy (can do talc pleurodesis)

Question 43

What is a haemothorax?

Answer 43

NOT a bloody effusion (HCT >50%)

Question 44

What are the causes of a haemothorax?

Answer 44

Traumatic

Iatrogenic

Aortic dissection

Question 45

How are haemothorax’s treated?

Answer 45

◦resuscitate

◦urgent drainage (“surgical” drain)

◦Consider VATS