The effect of recombinant growth hormone on the strength of ileal anastomoses in a rat model

OBJECTIVE: In gynecologic surgery, the ileum is the primary site of bowel injury. Recombinant growth hormone (rGH) has been shown to improve the strength of colonic anastomoses in experimental models. The purpose of this study is to evaluate the effect of rGH on small bowel anastomoses, specifically in the ileum. METHODS: Twenty large female rats underwent segmental ileal resections and end-to-end ileoileostomies. The rats were randomized to be treated for 7 postoperative days with either rGH (2.0 mg/kg/day) or placebo starting on the day of surgery. On the seventh postoperative day, a segment of ileum surrounding the anastomosis was resected. The anastomoses were tested for breaking strength on a tensiometer and for tissue concentrations of hydroxyproline. RESULTS: The ileal anastomotic breaking strength in the rGH group was 163.5 ± 6.0 g (mean ± standard error). In the placebo group, the breaking strength of ileal anastomoses was 125.0 ± 3.0 g (P < . 001). No significant difference was demonstrated with respect to the hydroxyproline concentration between the rGH group (15.2 ± 2.0 μg/mg) and the placebo group (14.6 ± 1.0 μg/mg). CONCLUSION: In an animal model, a 31% increase in ileal anastomotic breaking strength was induced by rGH administration. With further research this may translate into decreases in the surgical complications that occur in ileal anastomoses. Furthermore, these serve as preliminary data to a study that evaluates the effect of rGH on ileal anastomoses in radiation-injured bowel.