EFFECT OF PNEUMOTHORAX ON PLEURODESIS INDUCED WITH TALC IN RABBITS

Objective: The purpose of this study was to determine if a small pneum othorax would influence the pleurodesis resulting from talc instillati on. Methods: Sixty rabbits received an intrapleural injection of 400 m g/kg talc slurry. One half also received 10 mL of air intrapleurally a fter the talc. Ten rabbits in each group were killed 2, 14, and 28 day s after instillation. Results: Two days after the injection, the mean volume of air in the animals that had received the air was 7.5+/-0.4 m L. There was no air present in any other rabbits. The volume of pleura l fluid and the pleural fluid glucose, protein, cell count, and differ ential were similar in both groups on day 2, while the LDH level was s ignificantly higher in the air group (p<0.05), The degree of gross adh esions and microscopic fibrosis was similar in both groups and increas ed with time, Conclusions: A small pneumothorax does not decrease the efficacy of talc pleurodesis in our experimental model. These results suggest that the presence of a small amount of intrapleural air is not a contraindication to talc pleurodesis in humans.