Leakage of Colon Anastomoses: Development of an Experimental Model in Pigs

Abstract

Background: In order to investigate anastomotic leakage, a number of experimental animal studies have been previously carried out. Due to the low frequency of spontaneous anastomotic leakages, there have been studies on gastrointestinal anastomoses with iatrogenically produced leakages. A leakage model has only been developed in one gastric bypass study. The aim of the present study was to develop a leakage model of pig colon anastomoses. This type of study has never been performed before. Materials and Methods: Anastomosis was performed in 22 pigs. In all anastomoses a standardized rupture in the anastomotic line was made. The rupture ranged from 5 mm in the first group of pigs, increasing subsequently to 21 mm in the last group. Autopsy was performed after 7 days. The end points were macroscopic leakage and fecal peritonitis. Results: 6 out of the 6 pigs with a 21-mm rupture developed leakage and fecal peritonitis. In the groups with smaller ruptures, most of the pigs did not develop any signs of leakage or fecal peritonitis. The difference is significant. The group of pigs with peritonitis had significantly fewer adhesions to the anastomoses than the group without peritonitis. Conclusion: A model of anastomotic leakage on pig colon is developed with creation of a 21-mm rupture in the anastomotic line.

Circular anastomotic experimental fibrin sealant protection in deep colorectal anastomosis in pigs in a randomized 9-day survival study

“…This rate is within the range of literature-reported clinical situations in patients [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19] and could be reduced significantly by a circumferential extraluminal experimental fibrin sealant to the site of the circular anastomosis.…”

“…In this respect, Flodeen [29] analyzed 45 patients with EAL and LAL after LAR for rectal cancer. In this trial, 60 % (n=27) of symptomatic leakage was diagnosed during the initial hospital stay on median of eight postoperative days (3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18). However, 40 % (n=18) were diagnosed after discharge from hospital on a median of 22 postoperative days (33-172).…”

Choosing the Best Animal Species to Mimic Clinical Colon Anastomotic Leakage in Humans: A Qualitative Systematic Review

“…However, using the pig is limited by the cost of the animals, anesthesia during operation and monitoring equipment and facility demands [13]. Constructing a clinical leakage model in pigs resembling insufficient technique is possible as done by Nordentoft and Sorensen [40]. However, the method of creating leakage with large visible holes in the anastomosis upon construction might not closely resemble the mechanism in the clinical setting and a leakage rate of 100% rules out the possibility of detecting effects of interventions, which may potentially increase the anastomotic leakage rate.…”

“…Nordentoft and Sorensen [40] developed clinical leakage placing tubes with different diameters inside the anastomoses, leaving a defect behind in the suture line. All animals were sacrificed if showing signs of illness and the remaining part of the animals were sacrificed 7 days postoperatively.…”

Anastomotic Sealing by Extracellular Matrices (ECM) Improves Healing of Colonic Anastomoses in the Critical Early Phase

“…In rodent and porcine models, even primary dehiscent colonic anastomoses failed to reproduce the natural history of anastomotic leakage and its serious consequences comparable to the human scenario. [26][27][28] Therefore, if tested in animal models, other criteria need to be utilized to determine the effectiveness of anastomotic sealing in colonic healing. In this regard, besides macroscopic examination, anastomotic healing was evaluated by histological examination, applying an established scoring system for colonic wound healing.…”