Polylactic acid and polyethylene glycol prevent surgical adhesions

Re-mediastinoscopy could be risky because of adhesions from the previous mediastinoscopy. The aim of this study was to evaluate the efficacy of a bio-resorbable barrier on adhesion formation in a re-mediastinoscopy rat model. Mediastinal dissection similar to mediastinoscopy was done in twenty-eight rats and a polymeric film comprising of polylactic acid and polyethylene glycol (Repel-cv®, SyntheMed Inc., NJ, USA) was placed on trachea in the study groups. Group 1 (sham, sacrificed at day 30), Group 2 (single barrier, sacrificed at day 30), Group 3 (single barrier, sacrificed at day 60), Group 4(double layer barrier, sacrificed at day 60). Mediastinal adhesions, degree of inflammation, vascular proliferation, foreign body reaction and fibroblast proliferation was compared. Macroscopic dissection showed significantly dense adhesions in Sham Group and Group 3 (p < 0.05). Histopathologic examination showed that there was a significant difference between groups when the foreign body reaction and fibroblast proliferation was evaluated (p0.05). This unique experimental study showed that adhesion barrier was effective as single layer application at day 30 and double layer application at day 60. At clinical conversion, by the application of barrier, the formation of adhesions might be decreased to provide a safe re-mediastinoscopy (Tab. 2, Fig. 4, Ref. 23).