Pneumothorax + pleural disease Flashcards
Define simple pneumothorax
Presence of air within the pleural space
Air moves in and out
Define tension pneumothorax
- Presence of air within the pleural space
- Air moves in but NOT out
- Increases pressure in pleural space > pushes onto mediastinum
Types of pneumothorax
Simple
Tension
.
Iatrogenic/trauma
Spontaneous - primary or secondary
What are the types of spontaneous pneumothorax?
- primary: no underlying lung disease
- secondary: with existing lung disease
How is inspiration affected in a patient with a pneumothorax?
- air moves into pleura due to lower pressure
- air in pleura limits expansion of lungs
- causes higher pressure in lungs
- so there is a smaller pressure gradient in lungs compared to outside air
- less air moves into lungs
- inspiration is impaired
Symptoms of pneumothorax
Pleuritic chest pain
Dyspnoea
What is a spontaneous pneumothorax?
Occurs without obvious trauma/iatrogenic
Signs of pneumothorax
Reduced air entry
Hyper resonant
Reduced chest expansion
Diagnosis of pneumothorax
erect chest X ray
CT thorax to detect penumothorax that is too small to be seen on CXR
What are the radiological findings of a simple pneumothorax?
Lung doesn’t fill the whole chest
What would suggest a pneumothorax on percussion of the chest?
Hyper resonant
Management of a pneumothorax
Let the air out:
- needle aspiration
- intercostal chest drain
- pleural vent ambulatory device (outpatient)
.
- smoking cessation
- no flying until 2 week after resolution on CXR
- no scuba diving until reviewed by thoracic surgeons
BTS guidelines for spontaneous pneumothorax management (depending on risk)
- if high risk characteristics e.g hemodynamic instability, hypoxia, underlying lung disease: chest drain
- if symptomatic + of sufficient size: needle aspiration or pleural vent ambulatory device
Outline a pleural vent ambulatory device
- involves a catheter being inserted into the pleural space attached to a device stuck to the upper chest
- the device allows air to exit but not enter
- patients can wear as outpatients until pneumothorax is resolved
Describe the placement of an intercostal tube in the treatment of pneumothorax
- In the triangle of safety: under armpits at side of chest
- Above the rib to avoid damage to intercostal neurovascular bundle
Borders of the triangle of safety
- anteior: posterior border of pectoralis major
- posterior: anterior border of latissimus dorsi
- inferior: 5th intercostal space (in line with nipples)
- in mid axillary line
How do we prevent air entering the drain during treatment of a pneumothorax?
Underwater seal
Hickman valve
Complications of chest drains
- air leaks around drain site
- surgical emphysema: when air collects in SC tissue
Why is a water seal used during chest drains?
To prevent air entering the drain
Describe the clinical features suggestive of a tension pneumothorax
- Pleuritic chest pain
- Dyspnoea
- Tachycardia
- Low BP
- Cyanosis
- Deviated trachea
- Reduced air entry on affected side
Describe the radiological features suggestive of a tension pneumothorax
- Mediastinal shift
- Lung doesn’t fill to edges of ribcage
- tracheal deviation
Treatment of tension pneumothorax
Emergency chest drain
insert a large bore cannula into the 2nd ICS in midclavicular line
How does a pneumothorax cause a collapsed lung?
- Intrapleural pressure equalises with atmospheric pressure
- This changes the pressure differential between intrapulmonary + intrapleural pressure
- lung collapses due to change in trans pulmonary pressure
Define pleural effusion
Excess fluid in the pleura
Define haemothorax
Blood within the pleural space
Define chylothorax
Accumulation of lymph in the pleural cavity
Define parapneumonic effusion
Effusion next to pneumonia in the lung
Define empyema
Collection of pus within the pleural cavity
When should you suspect empyema?
in a patient with improving pneumonia but a new or ongoing fever
What is seen in pleural aspiration of empyema?
- pus
- low pH
- low glucose
- high LDH
Treatment of empyema
chest drain + antibiotics
