Transcatheter instillation of urokinase into loculated pleural effusion: Analysis of treatment effect

Abstract

OBJECTIVE. Our objective was to evaluate the usefulness of intracavitary instillation of urokinase in the treatment of loculated pleural effusion. SUBJECTS AND METHODS. We analyzed CT and sonographic scans of 31 patients with loculated effusion with intracavitary urokinase. When the drainage was less than 100 ml/day, urokinase was instilled through the catheter until the drainage was less than 50 ml/day. Response to the treatment was assessed on follow-up chest radiographs and classified into three groups: completely effective (lung expansion >80%), partially effective (20-80%), and effective (<20%). The sonographic pattern of pleural fluid was classified as anechoic, linear septated, or honeycomb, and thickness of the parietal pleura was measured on CT scans. RESULTS. Of the 16 patients in whom treatment was completely effective, sonography showed an anechoic appearance in 12 and a linear septated appearance in four, and the thickness of the parietal pleura on CT scans was 2 mm in six, 3 mm in seven, and 4 mm in three. Of the nine patients in whom treatment was partially effective, sonography showed an anechoic appearance in six and linear septated appearance in three, and the thickness of the parietal pleura on CT scans was 3 mm in five and 4 mm in four. Of the six patients in whom treatment was ineffective, sonography showed a linear appearance in one and a honeycomb appearance in five, and thickness of the parietal pleura on CT scans was 3 mm in one, 4 mm in two, 5 mm in one, and 6 mm in two. CONCLUSION. Urokinase instillation through a percutaneous catheter was effective in the treatment of loculated pleural effusion in most patients was not effective in patterns whose pleural fluid had a honeycomb appearance on sonography or whose parietal pleura had a thickness of more than 5 mm on CT scans.