Pneumothorax Flashcards
What is a tension pneumothorax?
Tissue forms a one way valve allowing air into the pleural cavity but preventing its escape
Build up of pressure pushes mediastinum to opposite side which results in obstruction of venous return to the heart
What does the pleural cavity normal contain?
Serious fluid that allows lubrication of lungs against chest wall to prevent friction
Why is there negative pressure in the pleural cavity?
Vacuum assists lung expansion on inspiration
What are ‘secondary’ prior events?
E.g. COPD or previous chest surgery
Signs
Tachypnoea Bruising Tenderness over ribs Trachea deviated away from pneumothorax Surgical emphysema – crunching Decreased lung expansion Increased percussion sounds Decreased breath sounds Raised central venous pressure Hypotension Hypoxia
What is surgical emphysema?
Air enters the skin of the chest wall
Symptoms
Chest pain
Shortness of breath
Prior events
When does a pneumothorax become ‘large’?
> 2cm between lung margin and chest wall
Can you fly after a pneumothorax?
non-traumatic: CXR must confirm resolution before flight
Traumatic: time period of 2 weeks after full radiographic resolution
risk of recurrence does not decline for a year
What can cause a primary spontaneous pneumothorax?
Smoking
Family history
(can be small and resolve themselves)
What is pleurodesis?
Sticking the lung to the chest wall if there is a significant risk of repeated episodes of pneumothorax
What is the risk of recurrence after the first spontaneous pneumothorax? after the second?
10%
40%
Why do spontaneous penumothoraces usually arise?
Rupture of small sub pleural blebs - thin walled spaces containing air.
