Pneumothorax Flashcards
Define Pneumothorax
Air enters and accumulates in the pleural space
Primary: without clinically apparent pulmonary disease
Secondary: occurs as a complication of an underlying pulmonary disease e.g. COPD, asthma, thoracic endometriosis
Aetiology of Pneumothorax
Often spontaneous due to sub-pleural bulla
Alveolar pressure > intrapleural pressure so any communication between alveolus and pleural space means gas will follow the pressure gradient
Caused by:
Trauma
Iatrogenic (subclavian CVP line insertion, pleural aspiration/biopsy, transbronchial biopsy, liver biopsy)
What is a tension pneumothorax
Medical emergency that occurs when intrapleural pressure exceeds that of atmospheric pressure (especially in expiration)
The build up of pressure results in hypothermia and respiratory failure due to lung compression
Risk factors for Pneumothorax
Smoking
Male
Tall and slender
Family history
Primary: young <40
Secondary: >55
Recent invasive medical procedure or chest trauma
Acute severe asthma or COPD
TB
Cystic fibrosis
Carcinoma
Sarcoidosis
Marfan’s, Ehler’s Danlo’s
Symptoms of Pneumothorax
Asymptomatic
OR
Sudden onset:
Dyspnoea
Pleuritic chest pain
Signs of Pneumothorax
Ipsilateral:
Reduced breath sounds
Hyperinflation of the hemithorax -> reduced epxansion
Hyper-resonance on percussion
Hypoxia
Tension: tracheal deviation away
Investigations for Pneumothorax
CXR: area devoid of obvious lung markings, visible rim between lung margin and chest wall
Clotting studies and INR: before chest drain insertion
ABG: (If sats <92 on air) -> resp. Alkalosis, acute respiratory acidosis
USS: absence of lung sliding, “A line sign”, “Lung point”, “Barcode sign”
CT: visible pleural line, atelectasis of the lung or hyper-expansion of ipsilateral hemithorax, signs of underlying lung disease
Do NOT delay tension pneumothorax treatment
Management of primary Pneumothorax
No or minimal symptoms → discharge with follow up every 2-4 days
Air <2cm on CXR + symptoms → ? high risk characteristics →
- Discharge + OPD review
- Ambulatory device (rocket pleural vent)
- Needle aspiration
SOB OR rim of air >2cm on CXR:
Needle aspiration using 16-18G cannula
Repeat CXR to see if rim is <2cm
If not → chest drain insertion
Follow up OPD 2-4 weeks
Management of secondary Pneumothorax
SOB and/or rim of air >2cm on CXR
Chest drain insertion
Rim of air 1-2cm on CXR
1. Aspirate <2.5L using 16-18G cannula
2. Repeat CXR
3. Rim >1cm → chest drain insertion + oxygen + admit
4. Rim <1cm → high flow oxygen and admit
What indicates surgery for patients with Pneumothorax
Bilateral Pneumothorax
Lung fails to expand within 48hours of drain
Persistent air leak
2 or more previous events on the same side
History on the other side
Management for tension Pneumothorax
Call cardiac arrest team
Insert large bore (14-16G) needle with a syringe partially filled with 0.99% saline into the 2nd ICS in the MCL on the suspected side
Remove the plunger to allow trapped air to bubble through the syringe until a chest drain can be placed
OR
Insert large bore Venflon in the same location
Complications of Pneumothorax
Re-expansion pulmonary oedema
Talc pleurodesis-related ARDS
Tension: great vein compression -> cardiorespiratory arrest
Prognosis for Pneumothorax
Primary: higher risk of recurrence (30-50% ipsilateral), higher risk of contralateral primary spontaneous pneumothorax
Secondary: greater risk of recurrence, typically secondary spontaneous pneumothoraces
High-risk characteristics for pneumothorax
haemodynamic compromise (suggesting a tension pneumothorax)
significant hypoxia
bilateral pneumothorax
underlying lung disease
≥ 50 years of age with significant smoking history
haemothorax
Advice after treatment for pneumothorax
Avoid smoking
Do not fly for 2 weeks after successful drainage
Diving should be permanently avoided unless the patient has undergone bilateral surgical pleurectomy and has normal lung function and chest CT scan postoperatively
