Initial Management of Trapped Lung

Understanding Trapped Lung

The European Respiratory Society recommends the initial management of trapped lung to be the placement of an indwelling pleural catheter (IPC) for symptomatic relief, providing effective palliation with minimal hospitalization and avoiding futile attempts at pleurodesis in a lung that cannot expand, as stated by the European Respiratory Journal 1, 2
Trapped lung occurs when the lung cannot fully expand to fill the hemithorax due to a fibrous visceral pleural peel from remote inflammation, preventing apposition of visceral and parietal pleura, according to the European Respiratory Journal 2

The European Respiratory Society and European Association for Cardio-Thoracic Surgery guidelines recommend IPCs as the first-line intervention for trapped lung, based on evidence of symptomatic benefit, including symptomatic improvement in >94% of patients across five studies totaling 133 patients, as reported in the European Respiratory Journal 1, 2
IPCs provide higher effusion control rates compared to talc pleurodesis, and better dyspnea-free exercise scores, with a significant reduction in hospitalization time, as stated in the European Respiratory Journal and Thorax 2, 3

The use of IPCs in trapped lung patients results in symptomatic benefit in the vast majority of patients, with common complications including pain, local cellulitis, catheter blockage, infection, or fracture, and rare but serious complications like empyema, as reported in the European Respiratory Journal and Thorax 2, 3

Pleurodesis is contraindicated in trapped lung, as it will fail due to the inability of the visceral and parietal pleura to appose, and attempting pleurodesis in trapped lung subjects patients to unnecessary procedures, prolonged hospitalization, and significant pain without therapeutic benefit, as stated in the European Respiratory Journal and Thorax 2, 3

Video-assisted thoracoscopic partial pleurectomy/decortication (VAT-PD) can be considered in highly selected patients, though evidence is limited, and pleuroperitoneal shunts are an alternative option but have high complication rates, as reported in the European Respiratory Journal and Thorax 1, 2, 3
Intrapleural fibrinolytic therapy via IPCs in trapped lung remains investigational, with limited evidence, as stated in the European Respiratory Journal 1

The American Thoracic Society recommends thoracentesis as the initial step for symptomatic patients with pleural effusions to both relieve dyspnea and determine the effect on symptoms 4
Malignancy should be considered and a diagnostic thoracentesis performed in any individual with a unilateral effusion, especially in a patient who may be at higher risk for malignancy 5
Standard pleural fluid tests should include: cell count and differential, protein, LDH, glucose, pH, and cytology 5
If diagnosis remains unclear after initial thoracentesis, consider CT scan of the chest (with pleural contrast in venous phase) if not already performed 6
Medical thoracoscopy may be indicated if diagnosis remains elusive, as it reduces undiagnosed effusions to less than 10% compared to >20% with fluid analysis and closed needle biopsy alone 7

For malignant effusion, if dyspnea is relieved by thoracentesis, consider pleurodesis or indwelling pleural catheter for recurrent effusions 4
Complete lung expansion should be demonstrated before attempting pleurodesis 8
Before attempting pleurodesis for malignant effusions, complete lung expansion should be demonstrated 8
If contralateral mediastinal shift is not observed with a large pleural effusion, consider endobronchial obstruction or trapped lung 8
Bronchoscopy is indicated when endobronchial lesions are suspected due to hemoptysis, atelectasis, or large effusions without contralateral mediastinal shift 7
If dyspnea is not relieved by thoracentesis, investigate other causes such as lymphangitic carcinomatosis, atelectasis, thromboembolism, or tumor embolism 8