INTESTINAL ANASTOMOTIC HEALING AT VARYING TIMES AFTER IRRADIATION

The use of preoperative and intraoperative irradiation as surgical adj uncts in cancer management has led to concerns regarding post-operativ e wound healing. The optimum time to construct an intestinal anastomos is after irradiation has not been determined, The aim of this study wa s to evaluate anastomotic wound healing at varying times after irradia tion. One hundred eighty-seven male Sprague-Dawley rats were randomize d into seven experimental groups. Group I (control) had a sutured anas tomosis and no irradiation. Groups II-VII received a single dose of 20 Gy intraoperatively. In group II, a sutured anastomosis incorporating irradiated bowel was performed immediately after irradiation, Groups III-VII underwent a second laparotomy to undergo a sutured anastomosis with irradiated bowel at 2 days, 1 week, 2 weeks, 3 weeks, and 4 week s after irradiation, The rats were sacrificed 7 days after the anastom osis was created and the segment of terminal ileum containing the anas tomosis was harvested, Tensile strength, hydroxyproline content, and m odified Black irradiation damage scores were determined: [GRAPHICS] Th e increasing modified Black scores reflect the progressive nature of i rradiation damage over time, Increasing hydroxyproline content is seen after irradiation but this does not imply increasing wound strength. There was a return of tensile strength to normal levels by 2 weeks. Th ese findings suggest that normal wound healing can be expected if a mi nimum of 2 weeks elapses between irradiation and intestinal anastomosi s. (C) 1996 Academic Press, Inc.