title: Evaluation of unmeshed and 1:1 meshed AlloDerm bolsters for stapled rectal anastomoses in a porcine model.
abstract: BACKGROUND
  The major morbidity of colorectal anastomoses is leaks. The concept of staple-line reinforcement is a growing area of interest. In this study, we evaluated the feasibility and effect of utilizing AlloDerm to bolster end-to-end stapled rectal anastomoses in a porcine model.
  
  
  METHODS
  A total of 30 female 45-kg domestic pigs were studied, and each served as its own control by creating a bolstered and unbolstered anastomosis in each animal. All anastomoses were created with a 29-mm end-to-end stapling device. Bolstered anastomoses were randomized to proximal and distal positions along the rectum, and each rectorectal anastomosis was separated by an average of 10 cm. In 20 pigs, an unmeshed bolster of a 0.5-0.7-mm thickness was used. The remaining 10 pigs had a 1:1 meshed bolster that was 0.34-0.51 mm thick. The animals were survived for 14 days. Barium enemas were then performed and the two anastomotic sites harvested, and each anastomosis underwent burst testing. The internal diameter of each anastomosis was measured and a biochemical analysis was performed for matrix metalloproteinase (MMP), elastin and collagen content.
  
  
  RESULTS
  The unmeshed bolstered anastomoses burst fewer times than the unbolstered anastomoses (P=0.004) and had higher burst pressures (P=0.023), though their anastomotic circumferences were smaller (P=0.007). Meshed bolsters offered no strength advantage to anastomoses and were significantly (P=0.009) smaller than unbolstered anastomoses in the same animal. No difference in elastin, collagen, or MMP content was observed between bolstered and unbolstered groups. No animals had clinical or radiographic leaks.
  
  
  CONCLUSIONS
  The routine use of unmeshed and 1:1 meshed AlloDerm bolsters is safe and does not appear to inhibit healing in elective colorectal surgery on healthy subjects. AlloDerm may have a role as a tissue bolster in select patients who are more prone to develop anastomotic leaks.
authors: Department of Surgery/Section of Colon and Rectal Surgery, Washington University School of Medicine, St. Louis, Missouri 63110, USA. stewartd@wudosis.wustl.edu
authors: David
authors: D
authors: Stewart
authors: Juan
authors: J
authors: Perrone
authors: Richard
authors: R
authors: Pierce
authors: Barry
authors: B
authors: Starcher
authors: Dongli
authors: D
authors: Mao
authors: Margaret
authors: M
authors: Frisella
authors: Kathryn
authors: K
authors: Cook
authors: James
authors: J
authors: Fleshman
authors: Steve
authors: S
authors: Hunt
mesh_terms: D000714:Anastomosis, Surgical / Q000379:methods*; D000818:Animals; D003094:Collagen / Q000032:analysis; D004549:Elastin / Q000032:analysis; D005260:Female; D020782:Matrix Metalloproteinases / Q000032:analysis; D011183:Postoperative Complications / Q000517:prevention & control; D011474:Prosthesis Design; D011897:Random Allocation; D012007:Rectum / Q000601:surgery*; D017768:Skin, Artificial; D013537:Sutures; D013552:Swine
chemical_list: C440568:Alloderm; D003094:Collagen; D004549:Elastin; D020782:Matrix Metalloproteinases