Pleural disease Flashcards
What is a pleural effusion?
Collection of fluid in the pleural cavity
Fluid can be of what two types?
How do these differ?
- Transudative - lower protein count (<3g/dL)
- Exudative - high protein count (>3g/dL)
Cause of exudative effusion
Inflammation
Results in protein leaking out of the tissues in to the pleural space
List 4 Exudative causes of pleural effusion
- Lung cancer
- Pneumonia
- Rheumatoid arthritis
- Tuberculosis
Cause of transudative effusion
Related to fluid moving across into the pleural space
List 4 Transudative causes of pleural effusion
- Congestive cardiac failure
- Hypoalbuminaemia
- Hypothroidism
- Meig’s syndrome
What criteria allows differentiation of a transudate vs exudate
In what instance is it used?
Light’s criteria
Should be used on if the protein level is between 25-35 g/L
Explain lights criteria
An exudate is likely if at least one of the following are met:
- pleural fluid protein divided by serum protein >0.5
- pleural fluid LDH divided by serum LDH >0.6
- pleural fluid LDH more than two-thirds the upper limits of normal serum LDH
What is Meig’s syndrome?
Right sided pleural effusion with ovarian malignancy
How does a pleural effusion present?
- SOB
- Dullness to percussion over the effusion
- Reduced breath sounds
- Tracheal deviation away from the effusion if large
Investigations for a pleural effusion?
Highlight the first line
- Chest X-ray
- USS: for aspiration
- Contrast CT: to identify cause
List 4 X-ray findings which may be seen in a pleural effusion
- Blunting of the costophrenic angle
- Fluid in the lung fissures
- Meniscus
- Tracheal and mediastinal deviation
What size needle and syringe should be used in aspiration of a pleural effusion?
21G needle and 50ml syringe
What should be tested in a Pleural aspiration
- pH
- protein
- lactate dehydrogenase (LDH)
- cytology and microbiology
What should be tested in a Pleural aspiration
- pH
- protein
- lactate dehydrogenase (LDH)
- cytology and microbiology
List 2 ddx for low glucose on pleural aspiration
RA or TB
List 2 ddx for raised amylase on pleural aspiration
- Pancreatitis
- Oesophageal perforation
List 3 ddx for heavy blood staining on pleural aspiration
- Mesothelioma
- PE
- TB
Treatment of a pleural effusion?
- Conservative management for small effusions
- Pleural aspiration for larger effusions (temporary relief)
- Chest drain (to drain effusion and prevent reoccurrence)
What is Empyema
An infected pleural effusion
List 4 findings on pleural aspiration which indicate Empyema?
- Pus
- Acidic pH (pH < 7.2)
- low glucose
- high LDH
How is Empyema treated?
Chest drain to remove the pus and antibiotics
What is a pneumothorax?
When air gets into the pleural space, separating the lung from the chest wall
Typical patient in exams is a tall, thin young man presenting with sudden breathlessness and pleuritic chest pain, possibly whilst playing sports
List 4 causes of a penumothorax
- Spontaneous
- Trauma
- Iatrogenic ie. lung biopsy, mechanical ventilation or central line insertion
- Lung pathologies ie. asthma or COPD
What is the investigation of choice for a simple pneumothorax?
Erect chest x-ray
What would be seen on x-ray in a simple pneumothorax?
Area between lung tissue and the chest wall where there are no lung markings
Line demarcating the edge of the lung
According the the BTS guidelines, how can the size of a pneumothorax be measured on x-ray?
Involves measuring horizontally from the lung edge to the inside of the chest wall at the level of the hilum
What investigation may be used if a pneumothorax is too small to be seen on x-ray?
CT thorax
Can also be used to accurately assess the size of the pneumothorax
How is the management of a pneumothorax be divided?
- No shortness of breath and less than a 2cm rim of air on the chest x-ray
- Shortness of breath and/or more than a 2cm rim of air on the chest x-ray
Treatment if there is no SOB and < 2cm rim of air on the chest x-ray?
- No treatment required, will spontaneously resolve
- Follow up in 2-4 weeks is recommended
Treatment if there is SOB and/or > 2cm rim of air on the chest x-ray?
- Aspiration followed by reassessment
- If aspiration fails twice, a chest drain is required
In what instances may a chest drain be required as first line management?
- Unstable patients
- Bilateral or secondary pneumothoraces
Chest drains are inserted in the “triangle of safety”
List the boarders of this
- 5th intercostal space
- Midaxillary line
- Anterior axillary line
Where is the needle inserted in relation to the rib?
Just above the rib to avoid the NV bundle
List 2 key complications of a chest drain
- Air leaks at drain site (indicated by persistent fluid bubbling, esp on coughing)
- Surgical emphysema when air collects in the subcutaneous tissue
