3 - pneumothorax Flashcards
definition of pneumothorax
accumulation of air in pleural space: secondary lung collapse
etiology of pneumothorax: 4?
rupture of visceral pleura with secondary air leak from lung. rupture of trachea/bronchus. rupture of esophagus. loss of integrity of chest wall.
classification of pneumothorax.
spontaneous (can be primary or secondary). traumatic. iatrogenic
physiology of pneumothorax
pressure is more negative at top than at base of lung. if air enters pleural cavity, lung collapses = decrease compliance = decrease FRC = decrease ventilation = decrease oxygenation
tension pneumothorax: severity? what happens?
life threatening. one way flow of air due to ball valve = progressive increase in pressure within pleural space = shifts mediastinum, can decrease venous return to heart = obstructive shock.
clinical symptoms and signs of pneumothorax
sudden chest pain and shortness of breath. tachynpea, tachycardia. hypotension. elevated JVP. decreased breath sounds. hyper resonance. tracheal deviation.
histopathology: blebs? bullae?
blebs = small, subpleural collection of air resulting from ruptured alveoli. bullae = large air filled spaces within lung associated with any form of emphysema (like a collection of blebs)
primary spontaneous pneumothorax: caused by? seen in who? recurrence? % tension?
rupture of subpleural blebs. in young, tall pts, males > females. recurrence 25% after 1, 50% after 2, 80% after 3. 5% are tension pneumos.
how to diagnose PSP
with symptoms and signs, and do an x ray: PA film with inspiratory AND expiratory views (because expiratory view can help accentuate)
how to manage PSP?
in a select few can observe. mostly will do a tube thoracostomy. might consider chemical pleurodesis or surgical management.
chemical pleurodesis: what? when to do?
induces pleural fibrosis and adhesions. only if pt refuses surgery or is high risk
when to do surgery for PSP?
first episode if: prolonged airleak, non re expansion, bilateral, tension, hemopheumothorax, occupational hazard, absence of facilities. will do it for a second episode for sure
what happens during surgery for a PSP?
resect blebs, then obliterate pleural space: can do an apical pleurectomy, or pleural abrasion (creates scar tissue = less likely to get tension pneumo if you get a another pneumothorax)
secondary sponatneous pneumothorax: in who? mortality?
in older patients with underlying pulmonary disease: like diffuse emphysema, bullous disease. higher mortality
most common cause of SSP? what happens? management?
COPD: rupture of bulla. usually with chest tube. might do surgery depending on comorbidity, more common to do chemical pleurodesis
