Pleural and chest wall disease Flashcards
Complete the diagram on how the chest moves in inspiration
How does expiration occur?
Expiration is passive
Elastic recoil
Natural elasticity of the lungs, which tend to collapse if they are not held against the thoracic wall
How does air enter the lungs?
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
What are the 2 causes of altered respiratory mechanics?
Chest wall (Kyphoscoliosis)
Respiratory muscle weakness
What is the pleura?
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
What are the 2 layers of the pleura?
Two layers – parietal and visceral pleura. Space between these two layers is the pleural space
Two sides are completely separate
What pressure is the pleural space and why?
Pleural space is normally at negative (subatmospheric) pressure
◦This keeps the lungs inflated
What is pleural fluid and what is its role?
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
How thick is the pleura?
Pleura is 0.3-0.5 mm thick
What happens when fluid or air move into the pleural space?
effusion or pneumothorax
Pleural effusion – fluid in the pleural space
Pneumothorax – air in the pleural space
What are the effects of pleural effusion/pneumothorax?
This accumulation of positive pressure within the pleural space leads to partial or complete collapse of the underlying lung
What are the types of pleural effusion?
◦Pleural infection/Empyema
◦Malignant Pleural Effusion
◦Heart failure
◦Haemothorax
What are the presenting features of a pneumothorax?
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
What does this show?
Pneumothorax
What are the subtypes of pneumothorax?
Tension pneumothorax -> ‘one way valve’
Primary/Secondary/Traumatic/ Iatrogenic (caused by hospital)
What is a primary spontanious pneumothorax?
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
What is a secondary pneumothorax?
◦Background of known lung disease eg: COPD, bronchiectasis, ILD etc
◦Mostly will need a drain
◦Tension more common
What are the possible outcomes in the BTS guidelines for manageing spontanious pneumothoraxes?
Discharge
Aspirate
Admit
Chest drain
When is pleurodesis performed?
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
What are the treatment options for recurrent primary pneumothorax?
Recurrent primary – Surgical / medical thoracoscopy and pleurodesis
What advice is given to pneumothorax patients?
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
How do pleural effusions occur?
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
What are the clinical features of a pleural effusion?
◦SOB, cough, pleuritic chest pain
◦Reduced breath sounds, “Dull” to percussion on examination
What does this show?
Pleural effusion
What are the causes of pleural effusion?
- Acute Vs Chronic, Benign Vs Malignant
- Altered permeability of the pleural membranes e.g. inflammation, infection, cancer
- Reduced oncotic pressure (low albumin) e.g. renal disease, liver cirrhosis
- Increased capillary hydrostatic pressure e.g. Heart failure
- Decreased lymphatic drainage or blockage e.g. malignancy, trauma
- Increased peritoneal fluid e.g liver cirrhosis, peritoneal dialysis
- Commonest causes are heart failure, pneumonia and malignancy
Name some examples of infective, benign and malignant causes of pleural effusion.
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
Pleural infections are uncommon.
True or false?
False
Common
- More than 30% of patients with _________ either die or require surgery.
- 20% 1 year mortality (this has been fairly consistent)
Pleural infection
What are the risk factors for pleural infection?
◦Diabetes
◦Immunosuppression (steroids)
◦Alcohol, IVDU
◦Poor oral hygiene and aspiration (anaerobic).
◦Iatrogenic e.g. previous pleural procedure
◦Trauma
◦Recent hospitalization
What does pleural effusion seen on CXR with systemic features of infection such as fever, raised CRP/WCC suggest?
Pleural infection
How is pleural infection diagnosed?
Take a pleural fluid sample
What are predictors of a worse outcome with pleural infection?
◦pH <7.2 High LDH
◦Low glucose (<2/3rd of serum glucose)
◦Positive culture
◦Loculations (seen on ultrasound or CT)
What are the 3 types of parapneumonic effusions?
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.
How are patients with pleural infection managed?
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.
Why does malignant effusion significantly impact quality of life?
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
What are the clinical features of malignant effusions?
Mostly unilateral
Massive unilateral effusion are usually not benign
Often present with breathlessness
Cough
Hypoxia
Mostly they are hemorrhagic
How are malignant effusions managed?
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
Why are indwelling pleural catheters the best option for malignant effusions?
Avoids patient admission to hospital.
Suitable for long term drainage
Improves quality of life
50% spontaneous pleurodesis
What is talc pleurodesis?
Pleurodesis - sticking together pleura
‘Medicated’ talc
Creates a talc ‘slurry’ (a bit like glue) to stick the pleura together
Works in about 70%
When is talc pleurodesis used?
Talc pleurodesis for Pleural Effusions (without infection)
To prevent recurrence
What are the dangers of talc pleurodesis?
Lung needs to be reinflated, and output <200ml/24hr
Drain can’t be blocked! Drain needs to not fall out!
Pain, fever
Which surgical procedures are used for pleurodesis?
VATS Pleurodesis
Medical Thoracoscopy (can do talc pleurodesis)
What is a haemothorax?
NOT a bloody effusion (HCT >50%)
What are the causes of a haemothorax?
Traumatic
Iatrogenic
Aortic dissection
How are haemothorax’s treated?
◦resuscitate
◦urgent drainage (“surgical” drain)
◦Consider VATS
