Outcomes of an algorithmic approach to management of pneumothorax complicating thermal ablation of pulmonary neoplasms

Purpose: To investigate the outcomes of an algorithm for treatment of pneumothorax in association with radiofrequency (RF) and microwave (MW) ablation of pulmonary neoplasms. Materials and Methods: This retrospective study included data from 248 ablation sessions for lung tumors in 164 patients (92 men; mean age, 59.7 y ± 9.8): 200 RF ablations (80.6%) and 48 MW ablations (19.4%). Pneumothorax was classified as mild, moderate, or severe. Twelve patients developed mild pneumothorax and were observed for further complications, and 33 developed moderate or severe pneumothorax and were managed with percutaneous aspiration of the pneumothorax. The decision to abort or continue ablation was determined based on clinical response to percutaneous aspiration, clinical distress, and feasibility of applying the applicator within the lesion. Results: Incidence of pneumothorax was 18.1% (45 of 248 sessions), with four (8.9%) occurrences during MW ablation and 41 (91.1%) during RF ablation. Pneumothoraces were mild in 12 sessions (26.7%), moderate in 27 (60%), and severe in six (13.3%). Complete evacuation of the pneumothorax was achieved in 25 of 33 sessions (75.8%). Intercostal tube drainage was indicated in eight sessions (24.2%), including six severe and two moderate pneumothoraces. Pneumothorax evolved immediately after thoracic puncture in 10 patients. Ablation therapy was aborted in two sessions in which severe pneumothorax occurred, and an intercostal chest tube was inserted. Conclusions: Mild pneumothorax can be managed by close observation without interruption of ablation therapy. Manual evacuation was an effective strategy for management of moderate pneumothorax and allowed for adequate positioning of the electrode, but did not suffice for severe and progressive pneumothorax, which required placement of an intercostal chest tube. © 2011 SIR.