Effectiveness and predictability of pleurodesis with the Tachosil® surgical patch compared with talc poudrage: an experimental study

OBJECTIVES: The human fibrinogen/thrombin surgical patch is proposed for videothoracoscopic pleurodesis after recurrent observation in routine clinical practice of site-specific pleuro-pulmonary adhesions. METHODS: A total of 36 experimental videothoracoscopies were performed on 18 pigs, all of which underwent a bilateral sequential procedure. The right or left side was casually approached and two 4.8 × 4.8 cm Tachosil® patches were placed over the dorsal lung surface in the highest antigravitary position through a double-port thoracoscopy. The contralateral side was subsequently entered by a single-port thoracoscopy to perform talc poudrage in accordance with current recommendations (1 g/18 kg). Thoracoscopy and autopsy were performed after 60 days to evaluate the outcome. Pleurodesis was graded on a predefined three-tier scale (none-moderate-firm); specimens were then submitted to the pathologist. The statistical analyses performed were: frequencies distribution, variables association test and hypothesis testing using binomial distribution. RESULTS: Pleurodesis was firm in 15/18 cases (P = 0.004), moderate in 2/18, and none in 1/18 cases with the sealant matrix. Talc pleurodesis was firm in 7/18 cases and moderate in 11/18. No surgical, medical, behavioural or growth disorders were recorded. There was complete correspondence between lung surface covered by the sealant patch and pleural adhesion topography (P < 0.001) and no other sites of adhesion were found at autopsy, whereas talc effect was commonly found to produce random pleural cavity obliteration, most frequently in declivous places, with inhomogeneous pleural adhesion for tissue density and rough/smooth outline (P < 0.001). The pathologist disclosed that talc creates a variable and unpredictable inflammatory background, sometimes severe, with the development of many granulomas. Fibrin sealant patch pleurodesis is caused by connective tissue irrespective of the pleural and pulmonary anatomy. CONCLUSIONS: The fibrin sealant patch is effective in producing localized pleurodesis in swine. The morphology and topography of the adhesions, 2 months after the patch placement, are consistent and more predictable than after talc poudrage. The latter causes a diffuse pleurodesis which is not predictable, with a predominantly gravitational location and produces a much more serious inflammatory response.