Methods: A total of 21 male New Zealand-type albino rabbits with an average weight of 3433 grams, were used in the study. One rabbit was used for blood supply. The other 20 rabbits were divided into four groups, including the control group, the heterologous blood group, the rifamycin group, and the talc group. Distilled water, heterologous fresh blood, rifamycin, and sterile liquid talc were administered through the catheter to the left hemithorax of rabbits. The rabbits were sacrificed using high-dose anesthesia on day 28. The pleural spaces were grossly assessed for evidence of pleurodesis and microscopic thickness of the pleura, and evidence of inflammation and fibrosis were examined. The degree of pleurodesis was rated on a scale of 0 to 4.

Results: No statistically significant differences were observed between the control and heterologous blood groups at the macroscopic and microscopic level (p>0.05). The degree of pleurodesis in the talc and rifamycin groups was higher than in the control and heterologous blood group (p=0.04). No significant difference was observed between the talc and rifamycin groups in terms of macroscopic and microscopic examination (p>0.05). The median values of fibrosis thickness of the control, heterologous blood, rifamycin, and talc groups were 10 (10-29), 26 (10-71), 312 (264-351) and 304 (238-331) μm, respectively.

Conclusion: The efficacy of rifamycin pleurodesis in rabbits was microscopically and macroscopically similar to the talc group and superior to the control and heterologous blood group.