Pneumothorax rates in CT-Guided lung biopsies: a comprehensive systematic review and meta-analysis of risk factors

Objective: This systematic review and meta-analysis investigated risk factors for pneumothorax following CT-guided percutaneous transthoracic lung biopsy. Methods: A systematic search of nine literature databases between inception to September 2019 for eligible studies was performed. Results: 36 articles were included with 23,104 patients. The overall pooled incidence for pneumothorax was 25.9% and chest drain insertion was 6.9%. Pneumothorax risk was significantly reduced in the lateral decubitus position where the biopsied lung was dependent compared to a prone or supine position [odds ratio (OR):3.15]. In contrast, pneumothorax rates were significantly increased in the lateral decubitus position where the biopsied lung was non-dependent compared to supine (OR:2.28) or prone position (OR:3.20). Other risk factors for pneumothorax included puncture site up compared to down through a purpose-built biopsy window in the CT table (OR:4.79), larger calibre guide/ needles (<= 18G vs >18G: OR 1.55), fissure crossed (OR:3.75), bulls crossed (OR:6.13), multiple pleural punctures (>1 vs 1: OR:2.43), multiple non-coaxial tissue sample (>1 vs 1: OR 1.99), emphysematous lungs (OR:3.33), smaller lesions (<4 cm vs 4cm: OR:2.09), lesions without pleural contact (OR:1.73) and deeper lesions (>= 3cm vs <3cm: OR:2.38). Conclusion: This meta-analysis quantifies factors that alter pneumothorax rates, particularly with patient positioning, when planning and performing a CT-guided lung biopsy to reduce pneumothorax rates. Advances in knowledge: Positioning patients in lateral decubitus with the biopsied lung dependent, puncture site down with a biopsy window in the CT table, using smaller calibre needles and using coaxial technique if multiple samples are needed are associated with a reduced incidence of pneumothorax.