Use of urokinase in childhood pleural empyema.

Urokinase is an enzyme with a fibrinolytic effect that facilitates pleural empyema drainage through a chest tube. The aim of this study was to assess the risk of pneumothorax, the need for pleural debridement surgery, the persistence of fever, and the number of days in hospital in a group of children with parapneumonic pleural empyema treated with urokinase. This was an uncontrolled retrospective study on children suffering from parapneumonic empyema. Data collected on 17 children treated with urokinase were compared with 11 children treated prior to the advent of urokinase (the "historic" group). The urokinase was instilled in the pleural cavity over a period ranging from 2-8 days, amounting to a median total dose per kilogram of body weight of 18,556 IU (range, 7,105-40,299). Surgical treatment of the empyema involved drainage tube placement and/or debridement of the pleural cavity. Three children developed pneumothorax during their hospital stay, and one more case occurred 6 months after the child had recovered from his empyema; there were 3 cases of pneumothorax during the acute phase in the "historic" group (P = 0.54). Five children in the urokinase group were debrided and 12 were only drained, as opposed to 9 and 2, respectively, in the "historic" group (P = 0.02). The overall hospital stay was 17 days for the urokinase group, and 24 for the "historic" group (P = 0.02). No bleeding or other major complications were reported in the group treated with urokinase. In conclusion, urokinase treatment does not carry a risk of pneumothorax, while it does reduce hospital stay and the need for pleural debridement.