Pneumothorax after small-bore catheter placement for malignant pleural effusions.

OBJECTIVE: The objective of this study was to evaluate the incidence and significance of pneumothorax after small-bore chest tube placement for symptomatic malignant pleural effusions.

SUBJECTS AND METHODS: Over a 2-year period, 90 patients with a known primary malignant tumor and symptomatic pleural effusion were referred to the radiology service at Duke University Medical Center. All patients underwent placement of a small-bore chest tube with fluid drainage in preparation for intrapleural sclerotherapy. Two of these patients were excluded because of coexisting empyema (n=1) and thoracentesis (n=1). The remaining 88 patients (30 men and 58 women; 26-86 years old [mean, 60 years old], who had 90 chest tubes placed, formed our study group. The incidence, duration, and clinical significance of their pneumothoraces and the amount of pleural effusion drained were recorded.

RESULTS: Among the 88 patients with 90 chest tubes, 27 patients with 28 chest tubes (31%) were found to have pneumothorax after the procedure. For 23 patients with 24 chest tubes, pneumothorax was evident on chest radiographs taken immediately after tube insertion and fluid drainage. Four patients with four chest tubes were found to have pneumothorax on chest radiographs taken the next day. No significant difference in the amount of fluid drained during the procedure was noted for patients with or without pneumothorax (831 ml versus 853 ml). No relationship between the size of each pneumothorax and the size of each drainage catheter was seen. The duration of pneumothorax ranged from 2 hr to 18 days (average, 3.5 days). Resolution of pneumothorax was seen in 22 (79%) of 28 cases; the remaining six cases of pneumothorax (21%) were stable, and the patients showed eventual fluid reaccumulation after chest tube removal and no sclerotherapy. No patient developed tension pneumothorax, respiratory distress, or other complications.

CONCLUSION: Pneumothorax should be recognized as a common finding after chest tube placement and immediate fluid drainage for malignant pleural effusions. We suggest that this finding is related to rapid removal of fluid from a relatively stiff, noncompliant lung. Patients whose lungs do not fully re-expand in several days will probably not benefit from sclerotherapy. Their tubes may be removed without risk of an enlarging tension pneumothorax.