Influence of Preoperative Feeding on the Healing of Colonic Anastomoses in Malnourished Rats

Background: Malnutrition influences healing of gastrointestinal anastomoses. The authors hypothesize that colonic anastomotic healing is decreased by malnutrition and might be improved by preoperative feeding. Methods: Eighty adult male Wistar rats were divided into 4 groups: (1) control rats 1 (C1), fed regular chow ad libitum for 21 days; (2) malnourished pair‐fed rats (M), fed 50% of the food ingested by the control rats for 21 days; (3) preoperative nutrition rats (PRE), fed 50% of the average of the controls for 21 days and then fed preoperative nutrition with regular chow ad libitum for 1 week before the operation; and (4) control rats 2 (C2), fed regular chow ad libitum for 28 days. On days 21 (C1 and M) and 28 (PRE and C2), rats underwent 2 colonic transections and, subsequently, 2 end‐to‐end anastomoses. Rats were killed on postoperative day 5. The anastomoses were ressected for tensile strength and histological analysis. Results: PRE rats showed increased maximal tensile strength vs the M group (0.09 ± 0.01 vs 0.15 ± 0.01; P < .05) and similar values of maximal tensile strength as the controls (0.15 ± 0.01 vs 0.15 ± 0.02; P = .91). Collagen type I was higher in controls vs the PRE group (6.13 ± 0.39 vs 4.90 ± 1.53; P < .05); nevertheless, the PRE group showed higher collagen type I than M rats (4.90 ± 0.36 vs 3.83 ± 0.35; P < .05). Conclusions: Preoperative feeding for 7 days increases the maximal tensile strength, as well as the percentage area of mature collagen, approaching similar values as the control group.