Management of Secondary Pneumothorax

Initial Assessment and Treatment

The American College of Chest Physicians recommends that all patients with secondary pneumothorax require active intervention and hospitalization, with chest tube drainage as the primary treatment for most cases, given the high failure rate of simple aspiration and the significant risk of respiratory compromise in patients with underlying lung disease 1, 2
Clinical stability must be assessed immediately using specific criteria: respiratory rate <24 breaths/min, heart rate 60-120 beats/min, normal blood pressure, room air oxygen saturation >90%, and ability to speak in complete sentences, as recommended by the American College of Chest Physicians 1, 3
Administering high-flow oxygen (10 L/min) immediately to all hospitalized patients increases pneumothorax reabsorption rate four-fold, though use caution in COPD patients who may be CO2 retainers, according to the British Thoracic Society 2, 4, 5
Any breathless patient requires immediate intervention regardless of pneumothorax size on chest radiograph, as stated by the British Thoracic Society 2, 4

Pneumothorax size determines treatment approach, with small pneumothorax defined as <2 cm rim between lung margin and chest wall (or <3 cm apex-to-cupola distance per ACCP criteria) and large pneumothorax defined as ≥2 cm rim (or ≥3 cm apex-to-cupola distance), as recommended by the American College of Chest Physicians and the British Thoracic Society 1, 2, 3
Simple aspiration may be attempted only in highly selected patients, such as those <50 years old, minimally breathless, and with pneumothorax <2 cm, with a success rate of only 33-67% in secondary pneumothorax, according to the British Thoracic Society 2, 6
Chest tube drainage is the definitive treatment for large secondary pneumothorax, with insertion of small-bore catheter (≤14F) or moderate-sized chest tube (16F-22F) and attachment to either Heimlich valve or water seal device, as recommended by the American College of Chest Physicians 1, 3

For small secondary pneumothorax (<2 cm) with minimal symptoms, observation alone is only appropriate for very limited cases, such as pneumothorax <1 cm depth or isolated apical pneumothorax in completely asymptomatic patients, according to the British Thoracic Society 2, 4
Hospitalization is mandatory even for observed cases, and all other small secondary pneumothoraces require active intervention, as stated by the British Thoracic Society 2, 4
For large secondary pneumothorax (≥2 cm) - clinically stable, chest tube drainage is the definitive treatment, with insertion of small-bore catheter (≤14F) or moderate-sized chest tube (16F-22F) and attachment to either Heimlich valve or water seal device, as recommended by the American College of Chest Physicians 1, 3
For large secondary pneumothorax - clinically unstable, immediate hospitalization with chest tube insertion is required, with use of 16F-22F chest tube or small-bore catheter depending on degree of instability, according to the American College of Chest Physicians 1, 3

Simple aspiration has much lower success rates in secondary pneumothorax (33-67% vs 59-83% in primary), making chest tube drainage the preferred initial approach for most patients, as stated by the British Thoracic Society 6
Age >50 years dramatically reduces aspiration success to only 19-31%, making chest tube insertion the clear choice in older patients, according to the British Thoracic Society 6
Underlying lung disease creates poor respiratory reserve, making observation inappropriate except in the most minimal cases, as stated by the British Thoracic Society 2, 4
Duration of symptoms >24 hours does not alter treatment recommendations, and chest tubes should remain in place until lung fully expands against chest wall and air leaks resolve, as recommended by the American College of Chest Physicians 1, 3
Natural reabsorption rate is only 1.25-1.8% of hemithorax volume per 24 hours, meaning a 15% pneumothorax takes 8-12 days to resolve without intervention, according to the British Thoracic Society 2, 5