734 Limitations apply to this study. Firstly, we defined bursting pressure as the primary outcome. Bursting pressure has been commonly linked with the occurrence of anastomotic complications such as abscess formation and leakage. Still, these complications can also occur irrespective of improved bursting pressure, for instance after irradiation [35]. In addition, bursting pressures are believed to be associated with collagen content. Yet, growth factor- induced proliferation and migration of cells might improve bursting pressure even without improving collagen content [36]. However, we did not use any radiation or growth factors in this study, limiting this potential source of bias and underlining the applicability of our primary outcome. Another possible limitation is the definition of an obstruction. In accordance with specific studies on this subject, we chose the clinical finding of a more than twofold distended bowel proximal to the anastomosis. This is in accordance with values found in an experimental obstruction model [37]. Nevertheless, even though a certain degree of constriction occurs at the anastomotic level, it is not clear whether it reaches a critical point at which symptoms occur [12]. With respect to this, the time of follow-up is of interest as well. Finally, translation of these experimental data to the human situation might be limited as parameters such as susceptibility to infections and the relation between the dimensions of colon and collagen fleece may apply. It could also be true that in a relatively small animal model such as this, the manipulations needed for application of the fleece induce more trauma than in a larger model. Therefore, we feel that further evaluation, for instance in a sufficiently powered pig model, is mandatory before routine application in a clinical setting. 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