Management of Small Pneumothoraces

Initial Assessment and Classification

The British Thoracic Society recommends that a 10 mm pneumothorax be classified as "small" and managed conservatively with observation and high-flow oxygen for minimally symptomatic patients, regardless of whether it is primary or secondary pneumothorax 1
Determining primary vs. secondary pneumothorax, symptom severity, and hemodynamic stability are critical first steps in management, with consideration of underlying lung disease such as COPD, emphysema, or interstitial lung disease 1, 2

For primary pneumothorax, conservative management is recommended for minimally symptomatic or asymptomatic patients, representing a shift from older guidelines that focused on size-based interventions 1, 3
Outpatient management is acceptable for patients with minimal symptoms, good social support, and reliable follow-up, with clear written instructions to return immediately if breathlessness worsens 1

Administering oxygen at 10-15 L/min via reservoir mask accelerates pneumothorax reabsorption up to four-fold, from 1.25-1.8% per day to approximately 4.2% per day 4, 2
Target oxygen saturation should be 94-98% in patients without COPD and 88-92% in patients with moderate-to-severe COPD or history of hypercapnic respiratory failure 4

Proceed to aspiration or chest tube if the patient develops worsening breathlessness or respiratory distress, pneumothorax progresses on serial chest radiographs, or no improvement after 24-48 hours of observation 1, 2
Simple aspiration is first-line treatment for primary pneumothorax requiring intervention, while chest tube placement may be more appropriate for secondary pneumothorax given lower success rates with aspiration 3

Serial chest radiographs are necessary to assess for progression during observation, with monitoring of respiratory rate, oxygen saturation, vital signs, and mental status changes 2, 4