Update on the role of intrapleural fibrinolytic therapy in the management of complicated parapneumonic effusions and empyema.

A parapneumonic effusion is the collection of exudative fluid in the pleural space associated with a concurrent pulmonary infection. Parapneumonic effusions account for approximately one-third of all effusions, and about 40% of patients with pneumonia develop a concomitant effusion. Patients with pneumonia who develop an effusion have an increased risk of morbidity and mortality. Some of the excess mortality is due to mismanagement of the parapneumonic effusion. Bacterial and white cell metabolism can rapidly turn a simple exudative parapneumonic effusion into a multiloculated purulent empyema with low pH and high lactate dehydrogenase levels. The optimal approach to treating parapneumonic effusions and pleural empyemas remains controversial. Accepted management consists of systemic antibiotics and drainage of the pleural cavity, which is achieved by either medical chest tube drainage or surgery. Several investigators have studied the efficacy and safety of intrapleural fibrinolytics in the treatment of pleural effusion and empyema. Intrapleural instillation of fibrinolytic agents is undertaken to dissolve fibrinous clots and membranes, to prevent fluid sequestration, and hence to improve drainage. Recombinant deoxyribonuclease has been reported to improve drainage in a single patient who did not respond to fibrinolytic therapy.