Pleural and Chest Wall disease Flashcards
Pleura
Covered by a layer of mesothelial cells
Pleural space normally at negative pressure and has a few mls of fluid for lubrication
Pleura is 0.3-0.5mm thick, but fluid forms a <1mm film
Fluid contains lymphocytes, macrophages and mesothelial cells (pH 7.6)
Fluid/air can move into pleural space - effusion/pneumothorax
This accumulation of positive pressure within pleural space -> partial or complete collapse of underlying lung
Pneumothorax
Air in pleural space
Entry of air creates positive pressure -> collapse of lung
Tension pneumothorax -> one way valve
Primary/secondary/traumatic/iatrogenic (caused by procedures/doctors)
1) Primary Spontaneous Pneumothorax
2) Secondary Pneumothorax
1) Occurs in healthy young tall males Apical blep More common in smokers (esp cannabis) Tension - rarely occurs Managed according to size and symptoms of patient Won't always need a drain/admission 2) background of known lung disease (COPD, bronchiectasis, ILD) Mostly will need a drain Tension more common
Follow up and Advice
Primary - 54% recurrence in first 4 years, recurrent primary - surgical/medical thoracoscopy and pleurodesis
Secondary - attempt pleurodesis after the first episode as the recurrence rate is high
Advice: no deep sea diving, coast guards/naval officers/air force should change jobs, high altitude sports and travel done with caution, stop smoking, diving less that 10 feet depth is fine
Pleural Effusions
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
Clinical features: SOB, cough, pleuritic chest pain, reduced breath sounds, dull to percuss
Causes of Pleural Effusion
Acute vs chronic / benign vs malignant
Altered permeability of pleural membranes (infection, inflammation, cancer)
Reduced oncotic pressure - low albumin (renal disease, liver cirrhosis)
Increased capillary hydrostatic pressure (HF)
Decreased lymphatic drainage or blockage (malignancy, trauma)
Increased peritoneal fluid (liver cirrhosis, peritoneal dialysis)
Commonest causes: HF, pneumonia, malignancy
- infection - benign (high oncotic pressure: HF/fluid overload - low protein state, autoimmune disease, reactive PE, Dresslers syndrome) - malignant
Pleural Infection
Risk factors: diabetes, immunosuppression, alcohol, IVDU, poor oral hygiene, aspiration, iatrogenic, trauma.
Seen of CXR with systemic features of infection (fever, raised CRP, WCC) - take pleural fluid sample.
Predictors of worse outcome: pH <7.2, high LDH, low glucose, positive culture, loculations (seen on u/s or CT)
Spectrum of Parapneumonic effusions
Uncomplicated parapneumonic effusion: resolve on treatment of underlying pneumonia, may not need to be drained
Complicated parapneumonic effusion: bacterial invasion into pleural space, fibrin deposition may form locules/septations, patient will likely need a drain
Empyema: frank pus within pleural cavity, may organise with thickening of pleural surface preventing lung re-expansion and impairing lung function
Malignant Effusion
High recurrence rate
Median life expectancy - 6 months
Impact on wider health economy
Mostly unilateral
Massive unilateral effusion are usually not benign
Often present with breathlessness, cough and hypoxia
Mostly they are haemorrhagic
Management: minimally invasive and reduced number of interventions - aspiration, chest drain +/- pleurodesis, indwelling pleural catheter (avoids admission to hospital, suitable for long term drainage), thoracoscopic drainage + pleurodesis
Talc Pleurodesis for Pleural effusions
To prevent recurrence
Mediated talc
Creates a talc slurry to stick the pleura together
Works in 70%
Lungs need to be reinflated, and output <200ml/24 hrs
Drain cannot be blocked - needs to not fall out
Pain/fever
Haemothorax
Not a bloody effusion (HCT >50%)
Traumatic/iatrogenic
Aortic dissection
Depending on cause: resuscitate, urgent drainage, consider VATS
