EFFECTS OF EARLY POSTOPERATIVE 5-FLUOROURACIL AND AGING ON THE HEALING CAPACITY OF EXPERIMENTAL INTESTINAL ANASTOMOSES

Background Results from a previous study suggested that advanced age d oes not affect early repair of experimental intestinal anastomoses; Th e present study aimed to establish whether anastomotic healing is impa ired more easily in old animals by immediate postoperative chemotherap y. Methods Young adult (2-3 months) and old (27-30 months) rats underw ent resection and anastomosis of both ileum and colon. Within each age group, subgroups received intraperitoneal saline or 5-fluorouracil in a dose of 15 or 20 mg per kg per day from the day of operation onward s. After 7 days, anastomotic healing was assessed by wound strength an d collagen deposition in the wound area. Results No differences were f ound between young and old control groups. The higher dose of fluorour acil induced severe loss of strength with concomitant reduction of wou nd collagen, which was similar in both age groups (ileum: from 52(13) to 24(8) volume per cent in young animals and from 56(10) to 20(9) vol ume per cent in old animals; colon: from 58(10) to 37(18) volume per c ent in young animals and from 65(5) to 30(17) volume per cent in old a nimals). The lower dose of fluorouracil induced a significantly greate r loss of strength, measured as the bursting pressure, in the old anim als (150(49) versus 201(59) mmHg in colon of young rats). Conclusion I n this model early anastomotic repair in older animals proceeds normal ly under optimal conditions, but it is more easily disturbed in the pr esence of fluorouracil.