PLEURODESIS - STATE-OF-THE-ART

Pleurodesis aims to achieve a symphysis between parietal and visceral pleural surfaces, in order to prevent accumulation of fluid or air in the pleural space, Its major indications are malignant effusions and p neumothorax, and a re-expandable lung is essential for the success of the technique, Moreover, expectation of a reasonably long survival is important before attempting pleurodesis.A successful lung re-expansion is unlikely if the pleural pressure falls more than 20 cmH(2)O . L-1 of fluid removed, because there is a central bronchial obstruction or the lung is trapped by tumour and/or fibrin, Pleural fluid pH (<7.20) is a good indicator of the presence of trapped lung; moreover, a succe ssful pleurodesis is less likely when pH is low, and this parameter is also a good predictor for survival of the patients, Among the many sc lerosing agents that have been used for pleurodesis, talc has achieved the best results, with an average success rate of approximately 90%. The cellular and biochemical mechanisms involved in pleurodesis may be specific to the agent used, however, they may all follow a common fin al pathway leading to activation of the pleural coagulation cascade, t he appearance of fibrin networks, and the proliferation of fibroblasts , The details of these mechanisms are still unclear and need to be fur ther elaborated.