DOXYCYCLINE PLEURODESIS IN RABBITS - COMPARISON OF RESULTS WITH AND WITHOUT CHEST TUBE

We have reported previously that there is a, high incidence of hemotho rax and substantial mortality in rabbits that are given tetracycline d erivatives intrapleurally. However, such complications have not been r eported in humans when pleurodesis is attempted with tetracycline deri vatives, One primary difference in the two situations is that a chest tube is placed only in humans, The objective of this study was to eval uate the hypothesis that chest tube placement would prevent the develo pment of hemothoraces and lead to better pleurodesis in rabbits given doxycycline intrapleurally. Eighty New Zealand White male rabbits rece ived doxycycline, 20 mg/kg, in a total volume of 2 mt. One half of the rabbits were randomized to receive a chest tube at the time of the in jection and were subjected to pleural fluid aspiration twice daily, Th e remaining rabbits (control group) received no chest tube and no aspi ration, Ten rabbits from each group were killed on days 4, 7, 14, and 28, The intrapleural injection of doxycycline induced the production o f large exudative effusions, The insertion of chest tubes prevented th e development of hemothorax (0/20 in chest tube group, 15/20 in contro l group, p<0.001). The insertion of chest tubes was also associated wi th a significant reduction in mortality and a significant improvement in pleurodesis. When pleurodesis is attempted in rabbits with intraple ural doxycycline, the insertion of a chest tube will prevent hemothora x and lead to a better pleurodesis.