Esophagogastric anastomotic wound healing in rats

Esophagectomy with esophagogastric anastomosis is commonly complicated by anastomotic dehiscence. Although this is a major problem in clinical esophageal surgery, laboratory investigation of esophagogastric anastomotic wound healing has been hampered by the lack of a practical rodent model. Problems with aspiration pneumonia and anastomotic strictures hindered our previous studies in the rat. Other researchers have turned to large animal experiments, or used various upper gastrointestinal pseudoanastomotic techniques in rodents. None of these approaches has proved satisfactory. We developed a technique of side-to-side esophagogastric anastomosis in the rat, and then studied normal esophagogastric anastomotic healing in this model. Anastomoses were performed in 24 rats. Anastomotic breaking strength and hydroxyproline concentration were measured 1 and 2 weeks after surgery. Anastomotic breaking strength was 3.78 +/- 1.18 N at 1 week and 4.83 +/- 0.91 N after 2 weeks (p < 0.03). Anastomotic tissue hydroxyproline concentration was 370.6 +/- 31.2 nmol/mg at 1 week and 462.1 +/- 69.7 nmol/mg after 2 weeks (p < 0.001). Many of the problems encountered in esophagogastric anastomotic studies in the rat have been overcome using this new model.