Pneumothorax Flashcards
what is the pleural cavity
the potential space between the visceral and parietal pleural
what is pneumothorax
the presence/ accumulation of air or gas in the pleural cavity which can impair oxygenation and ventilation
etiological classification of pneumothorax
1st spontaneous
2nd spontaneous
traumatic
iatrogenic
1st spontaneous
- no underlying lung pathology evident
*more common in tall men aged 20- 4- years who smoke
*probably due to rupture of apical subpleural blebs/ bullae
2nd spontaneous
*pleural rupture due to underlying disease: emphysema, cystic fibrosis etc.
* infection through cavitating pneumonia e.g. Staphylococcus/ TB/ abscess
traumatic
penetrating/ blunt
iatrogenic
after pleural biopsy or aspiration, transbronchial biopsy, percutaneous lung biopsy, subclavian vein central line insertion, mechanical ventilation with high airway pressures
clinical presentation of pneumothorax
depends on the type of pneumothorax, and can be asymptomatic to potentially life- threatening
history on a patient with pneumothorax
patient can present with sudden onset SOB and/or chest pain
hallmarks physical exam findings on a patient with pneumothorax
decreased air entry on the affected side
hyper-resonance with percussion
investigations: CXR
look for hyperlucency of one lung field. be careful in COPD patients, it may bullous
small= visible rim <2cm measured a hilum
large=visible rim> 2cm measured at hilum
what does the management of a pneumothorax depend on
*spontaneous or not
*if spontaneous, is it primary or secondary
*symptomatic or not
*size of pneumothorax
management options
observation
aspiration
placement of an intercostal drain
indication for ICD placement
a. tension pneumothorax
b. primary pneumothorax with failed aspiration
c. secondary pneumothoraces in symptomatic patient> 50 yrs
d. associated blood/water/ pus
e. mechanically ventilated patients with pneumothorax
f. for interhospital transfer if a pneumothorax is present
g. traumatic pneumothorax
h. bilateral pneumothoraces
indication for aspiration
a. primary pneumothoraces not suitable for observation and no indication for ICD placement
b. small secondary pneumothoraces in minimally SOB patients <50 yrs of age
needle aspiration techniques
- patient must be admitted for 24 hrs on high flow O2
- it should be done under local anesthetic, until resistance is felt or patient coughs excessively
*it can be repeated
*repeat CXR 6hrs later
indications for in patient observation
All patient that do not meet criteria for needle aspiration or ICD placement need to be admitted for monitoring for 6 hours. This is done if the pneumothorax is small and the patient is not symptomatic. The patient is observed for 6 hours while placed on oxygen. A repeat CXR is done 6 hours later. If no expansion and patient has no symptoms and they are able to return to the hospital, they can be discharged.
use of face mask oxygen
· O2 accelerates the reabsorption of pneumothoraces up to 4 fold.
· Most of the pneumothorax is nitrogen (N2).
· O2 ↓ the partial pressure of N2 in the blood, thus ↑ the gradient for its reabsorption.
what is tension pneumothorax
Tension pneumothorax is the progressive build-up of air within the pleural space due to a ‘one-way-valve’ effect.
- Progressive build-up of pressure in the pleural space pushes the mediastinum to the opposite hemithorax and obstructs venous return to the heart.
- This leads to cardiovascular instability and will eventually lead to cardiac arrest if not treated promptly.
neuro clinical features of tension pneumothorax
Confusion, restlessness
resp clinical features of tension pneumothorax
- Extreme tachypnoea + hypoxia +/- cyanosis
- Uneven chest rise
- Tracheal shift to the opposite side
- Affected side hyperresonant with ↓ air entry
cvs clinical features of tension pneumothorax
- Diaphoresis, ↑JVP, tachycardia, Hypotension, Shock
(↑ intrathoracic pressure → ↓ venous return to the heart → ↓ cardiac output)
management of tension pneumothorax
- DON’T WAIT !!
- O2
- NEEDLE THORACOSTOMY
- Insert the largest available IV cannula perpendicular to the chest wall in the 2nd ICS mid-clavicular line on the side of the pneumothorax. Air should rush out..
Intercostal drain as soon as possible
