Int J Colorectal Dis (2011) 26:729–735 DOI 10.1007/s00384-011-1158-z ORIGINAL ARTICLE Collagen fleeces do not improve colonic anastomotic strength but increase bowel obstructions in an experimental rat model Marc H. Schreinemacher & Johanne G. Bloemen & Stijn J. van der Heijden & Marion J. Gijbels & Cornelis H. Dejong & Nicole D. Bouvy Accepted: 1 February 2011 / Published online: 23 February 2011 # The Author(s) 2011. This article is published with open access at Springerlink.com Abstract Purpose To investigate whether a collagen fleece kept in place by fibrin glue might seal off a colorectal anasto- mosis, provide reinforcement, and subsequently improve anastomotic healing. Methods Wistar rats underwent a 1-cm left-sided colonic resection followed by a 4-suture end-to-end anastomosis. They were then randomly assigned to one of three treatment groups: no additional intervention (control, n =20), the anastomosis covered with fibrin glue (fibrin glue, n= 20), the anastomosis covered with a collagen fleece, kept in place with fibrin glue (collagen fleece, n= 21). At either 3 or 7 days follow-up, anastomotic bursting pressure was measured and tissue was obtained for histology and collagen content assessment after which animals were sacrificed. Results Three rats in the control (15%), three in the fibrin glue (15%), and one in the collagen group (4.8%) died due to anastomotic complications (P= 0.497). Anastomotic bursting pressures were not significantly different between groups at 3 and 7 days follow-up (P= 0.659 and P= 0.427, respectively). However, bowel obstructions occurred sig- M. H. Schreinemacher (*) : J. G. Bloemen : S. J. van der Heijden : C. H. Dejong : N. D. Bouvy Department of General Surgery, Maastricht University Medical Centre, P.O. Box 5800, 6200 Maastricht, The Netherlands e-mail: m.schreinemacher@gmail.com M. J. Gijbels Department of Molecular Genetics, Maastricht University Medical Centre, Maastricht, The Netherlands M. J. Gijbels Department of Pathology, Maastricht University Medical Centre, Maastricht, The Netherlands nificantly more often in the collagen group compared to the control group (14/21 vs. 3/20, P= 0.003). Collagen contents were not different between groups, but histology showed a more severe inflammation in the collagen group compared to the other groups at both 3 and 7 days follow-up. Conclusions A collagen fleece kept in place by fibrin glue does not improve healing of colonic anastomoses in rats. Moreover, this technique induces significantly more bowel obstructions in rats, warranting further study before being translated to a clinical setting. Keywords Anastomotic dehiscence . Rat . Fibrin glue . Collagen fleece . Bursting pressure Introduction Clinically significant anastomotic leakages remain a major complication of colorectal surgery. Patients suffering from an anastomotic leakage undergo more radiological inter- ventions, reoperations, and often stay in ICU for prolonged periods of time. Moreover, they experience higher rates of mortality, lower quality of life, and higher rates of local recurrence in malignant disease [1–5]. In the past, there have been many studies—both animal and clinical—on anastomotic leakage prevention. A wide variety of interventions have been investigated aiming at adequate oxygenation and perfusion of the anastomotic region, stimulation of angiogenesis, administration of growth factors, and inhibition of matrix metalloproteinases [6–9]. Other ways to prevent leakages included a more mechanical approach with topically applied sealants and membranes such as fibrin glue and collagen fleeces, respectively. Fibrin sealants are human- and animal- derived tissue adhesive agents that can be used to enhance