Editing Pneumothorax (section)

== '''Aetiological classification''' ==

=== '''Spontaneous''' ===

** Primary spontaneous
*** Definition
**** Spontaneous pneumothorax in a patient without an immediately obvious underlying lung disease
*** Risk factors
**** Occurs between 20-30yo, mostly men
**** Smoking
**** Ectomorphic habitus
**** Genetics
**** Nitrous oxide canisters - inhaled under pressure
*** Pathophysiology
**** Rupture of small subpleural blebs (<2cm collections of air contained within visceral pleura), mostly found at apex of upper or lower lobes
**** Blebs result from ruptured alveoli - well-demarcated from normal lung, being located between elastic interna and externa of the visceral pleura
**** May be associated with apical fibrosis
**** PSP can also occur in the absence of blebs
** Secondary spontaneous PTX
*** Aetiology
**** COPD (marker of severe disease with poor prognosis)
**** Bullous disease
**** Cystic fibrosis (marker of advanced disease)
**** Pneumocystis-related
**** Congenital cysts
**** IPF
**** Pulmonary embolism
**** Asthma
**** TB and other mycobacterial infections
**** Other infections
**** AIDS
**** Bronchogenic carcinoma
**** Metastatic lung disease (especially metastatic sarcoma)
**** Radiotherapy
**** Marfan syndrome
**** EDS
**** Histiocytosis X
**** Sarcoidosis
**** Scleroderma
**** Lymphangiomyomatosis
**** Pregnancy - usually around 26 weeks
*** Management
**** Refer to respiratory physician if not already known
** Catamenial (occurs with 48-72 hours of onset of menstruation; part of thoracic endometriosis syndrome (TES) and in fact the most common presentation of that syndrome)
*** TES - haemothorax, haemoptysis, lung nodules. Growth of endometrial glands and stroma in the lungs, pleura, diaphragm and tracheobronchial tree. Mostly unilateral right PTX.
** Neonatal

=== '''Traumatic''' ===

** Generally sharp stumps of fractured ribs directed inwards, which can also cause HTX.
** Barotrauma from diving

=== '''Iatrogenic''' ===

** Mechanical ventilation
** Needle puncture (thoracentesis, FNA lung nodule, central line insertion
** Post-surgical