Management of Small Left Pneumothorax

Diagnosis and Initial Assessment

The treatment of a small left pneumothorax depends on whether it is primary or secondary, as this distinction determines whether observation alone is safe or active intervention is mandatory, according to the American Thoracic Society 1.

For minimally symptomatic primary pneumothorax, observation with outpatient management is appropriate, with no hospital admission required, as recommended by the British Thoracic Society 2, 3.
No intervention is needed for 70-80% of small primary pneumothoraces, as they resolve spontaneously, with a low recurrence rate, according to the British Thoracic Society 3.
The American College of Chest Physicians recommends that patients with primary pneumothorax who are discharged should be given clear written instructions to return immediately if breathlessness develops 3.

Observation alone is only acceptable for extremely limited cases of secondary pneumothorax: pneumothorax <1 cm depth or isolated apical pneumothorax in completely asymptomatic patients, as stated by the American Thoracic Society 1, 3.
The European Respiratory Society recommends that all other small secondary pneumothoraces require active intervention, such as aspiration or chest drain, due to the underlying lung disease creating poor respiratory reserve 1, 3.

For primary pneumothorax requiring intervention, simple aspiration should be attempted first, which succeeds in 59-83% of cases, according to the British Thoracic Society 2, 4.
The American College of Chest Physicians recommends using a small-bore catheter for the aspiration procedure and re-aspiration if the first attempt fails and <2.5 liters were aspirated 4, 5.
For secondary pneumothorax, simple aspiration has much lower success rates (33-67%) and should only be attempted in highly selected patients, as stated by the American Thoracic Society 1, 2.

If aspiration fails or the patient has secondary pneumothorax, a small-bore chest tube (10-14F initially) should be inserted, as recommended by the European Respiratory Society 6, 1.
The American College of Chest Physicians recommends attaching the chest tube to either a Heimlich valve or water seal device and using high-flow oxygen to increase pneumothorax reabsorption rate four-fold 1, 4.

The British Thoracic Society recommends administering high-flow oxygen (10 L/min) to all hospitalized patients to increase pneumothorax reabsorption rate four-fold, with caution in COPD patients who may be CO2 retainers 3, 1, 4.
Natural reabsorption without oxygen is only 1.25-1.8% of hemithorax volume per 24 hours, meaning a 15% pneumothorax takes 8-12 days to resolve, according to the American Thoracic Society 3, 1.

The American College of Chest Physicians recommends not relying solely on pneumothorax size to guide treatment, as clinical symptoms trump radiographic size, and not attempting observation for secondary pneumothorax unless it meets strict criteria 3, 1, 5.
The European Respiratory Society recommends not discharging patients with secondary pneumothorax after successful aspiration without 24-hour hospitalization and not applying suction immediately after chest tube insertion, waiting 48 hours for persistent air leak before adding suction 2, 1, 6.