pneumothorax Flashcards
definition
= accumulation of air in pleural spcae with 2ry lung collapse
how is it classified
closed- intact chest wall + air leaks from lung into pleural cavity
open- defect in chest wall allow communication between peumothrax + exterior- may be sucking
simple- non expanding collection of air around lung. no shift of heart or mediastinal structures.
tension- air enters pleural cavity via one way valve due to eg. lung laceration + cannot escape=> can get mediastinal compression. pos pressure ventilation may worsen/cause this.
spontaneous [non traumatic] -can be 1ry/2ry
traumatic - can be iatrogenic/accidental
- iatrogenic= invasive medical procedures eg. CV cannulation, pleural tap or biopsy, FNA, liver biopsy
- accidental- direct chest wall injury/laceration/fractured ribs
3 overall causes of pneumothorax
spontaneous
trauma
iatrogenic
spontaneous causes of pneumothorax
spontaneous 1ry
= no underlying lung disease
young thin men [ruptured subpleural bulla], smokers.
spontaneous 2ry
= underlying lung disease eg
COPD
marfans, ehler’s danlos
Pulm fibrosis, sarcoidosis
trauma causes of pneumothorax
penetrating
blunt injury
rib fractures
iatrogenic causes of pneumothorax
subclavian CVP line insertion
pos pressure ventilation
transbronchial biopsy
liver biopsy
s/s
symptoms
- sudden onset
- dyspnoea
- pleuritic chest pain
- tension- resp distress, cardiac arrest
signs
- chest: [VERB}
- decreased expansion
- resonant percussion
- decreased breath sounds
- decreased VR
- tension: high JVP, mediastinal shift, high HR, low BP
- crepitus: surgical emphysema
ix
- ABG: HYPOXIA
- hypoxaemia is greater in cases of SSP
- not required if the oxygen saturations are adequate (>92%) on breathing
- US =specific features on ultrasound scanning are diagnostic of pneumothorax but is mainly used in the management of supine trauma patients
- CXR
- presence of a white visceral pleural line separated from the parietal pleura and chest wall by a collection of gas, resulting in a loss of lung markings in this space is a hallmark of the condition
- mediastinal shift away from pneumothorax
tension pneumothorax mx
- reuscitate pt
- no cxr
- large bore venflon [cannula] intro 2nd ics mid clavic line
- insert intercostal chest drain [ICD]
traumatic pneumothorax mx
- reuscitate pt
- analgesia- morphine
- 3 sided wet dressing if sucking [acts as a flap valve]
= air allowed to escape from ptx during expo but to not enter on inspo
- now immediately place ICD!
1ry/2ry spontaneous pneumothorax mx
Primary pneumothorax
Recommendations include:
- if the rim of air is < 2cm and the patient is not short of breath then discharge should be considered
- otherwise aspiration should be attempted
- if this fails (defined as > 2 cm or still short of breath) then a chest drain should be inserted
- patients should be advised to avoid smoking to reduce the risk of further episodes - the lifetime risk of developing a pneumothorax in healthy smoking men is around 10% compared with around 0.1% in non-smoking men
Secondary pneumothorax
Recommendations include:
- if the patient is > 50 years old and the rim of air is > 2cm and/or the patient is short of breath then a chest drain should be inserted.
- otherwise aspiration should be attempted if the rim of air is between 1-2cm. If aspiration fails (i.e. pneumothorax is still greater then 1cm) a chest drain should be inserted. All patients should be admitted for at least 24 hours
- if the pneumothorax is less the 1cm then the BTS guidelines suggest giving oxygen and admitting for 24 hours
- regarding scuba diving, the BTS guidelines state: ‘Diving should be permanently avoided unless the patient has undergone bilateral surgical pleurectomy and has normal lung function and chest CT scan postoperatively.’