Effect of local and remote ischemia-reperfusion injury on healing of colonic anastomoses

Background. Although the effect of locally applied ischemia-reperfusion (I- R) injury on gastrointestinal anastomoses has been studied, to our knowledg e there is no previous study that investigates the effect of remote I-R inj ury on gastrointestinal anastomotic healing: The aim of this study was to i nvestigate and compare the effects of local I-R injury and remote I-R injur y on the healing of colonic anastomoses. Methods. Anastomosis of the right colon was performed in 30 mts that were d ivided into 5 groups. Group 1 was the control group. In Group 2, I-R was ap plied to the colonic segment containing the anastomosis. Unilateral lower e xtremity I-R, unilateral renal I-R, and segmental small intestinal T-R was applied to the rats in Groups 3, 4, and 5, respectively, at the same time a s colonic anastomosis. On the fourth postoperative day, animals were killed and bursting pressure and tissue hydroxyproline concentration of the anast omoses were analyzed and compared. Results. The mean bursting pressure values were: 143 mm Hg in Group 1, 40.8 mm Hg in Group 2, 82.8 mm Hg in Group 3 46.1 mm Hg in Group 4, and 52.3 mm Hg in Group 5 (P <.0001; 1-way analysis of variance). Mean tissue hydroxyp roline concentration values were: 5.3 mu g/mg in Group 1, 1.6 mu g/mg in Gr oup 2, 2.2 mu g/mg in Group 3 1.3 mu g/mg in Group 4, and 1.5 mu g/mg in Gr oup 5 (P <.0001, I-way analysis of variance). Bursting pressure and tissue hydroxyproline concentration values had a good correlation r = 0.86, P <.00 1, Pearson correlation analysis). Conclusions. This study showed that I-R injury is a systemic phenomenon, an d remote organ I-R can significantly delay anastomotic healing. This has to be kept in mind when constructing an intestinal anastomosis in the presenc e of focal or remote I-R injury.