Systemic distribution of talc after intrapleural administration in rats.

STUDY OBJECTIVES: Many reports have shown the efficacy of talc to induce an effective pleurodesis. However, there is little information about the side effects related to this sclerosing agent. The objective of this experimental study is to recognize the systemic distribution of talc after its instillation into the pleural space of rats. DESIGN: Forty animals were assigned to receive talc through a catheter placed in a left minimal thoracotomy. They were randomly divided in two groups: group 1 received 20 mg of talc and group 2 received 10 mg in the same total volume of 1 mL of saline solution. Half of the animals in each group were killed 24 h and the other half 48 h after the procedure. BAL was collected and histologic sections of both lungs, chest wall, liver, kidneys, spleen, heart, and brain were examined. Crystals were tracked using polarized light and we have used a "birefringent particles index of deposition" in an attempt to quantify the amount or talc encountered in different organs. RESULTS: Talc crystals were found in every organ of all animals studied (100%). There was no statistical difference either on the dose of talc used or in the time of death. The amount of talc was statistically different in the organs, which made us divagate about a route of absorption. CONCLUSIONS: We conclude that there is a progressive deposition of talc particles in the organs examined after its administration into the pleural space of normal rats. This report suggests that there is a rapid absorption of talc through the pleural surface and that the systemic distribution thereafter is not dose related. Further studies are necessary to assess the amount of crystals and the clinical correlation to these findings.

Thoracoscopy in children and adolescents.

STUDY OBJECTIVES: Present the feature characteristics of the use and findings of thoracoscopy in children and adolescents. DESIGN: From February 1983 to February 1996, 77 thoracoscopic procedures were done on patients ranging in ages from 5 months to 18 years (mean, 9.8 years). Two-thirds (66.2%) were male. They were divided into three groups (1, 2, and 3) based on age (up to 2, from 2 to 8, and older than 8 years), predominance of certain diseases in these ages, and the size of the instruments utilized. They were operated on using general anesthesia with Carlens' mediastinoscope routinely used in 64 (83%) and videothoracoscopy in 13 (17%). The chief indication for therapeutic thoracoscopy was treatment of empyema, while for diagnostic thoracoscopy it was pleural biopsy and diagnosis of pleural effusions. RESULTS: In group 1, thoracoscopy was solely for the treatment of pleural disorders. In group 2, it was for the treatment of pleuropulmonary diseases. Group 3 behaved almost like adults, with broad diagnostic and therapeutic indications for thoracoscopic procedure. CONCLUSIONS: Thoracoscopy, which is a useful diagnostic and therapeutic procedure, has secured an important place in pediatric surgical practice.