The effect of ischaemia on anastomotic wound healing in the rat stomach

Dehiscence of oesophagogastrostomy anastomoses is a major cause of mortality after oesophagectomy. Clinical research suggests that gastric ischaemia is an important etiological factor, but little experimental work has been done. The stomach, as opposed to the oesophagus, is the ischaemic component of oesophagogastrostomy anastomoses. Therefore, a small animal model was developed to study the effect of ischaemia on gastric anastomotic wound healing. 40 rats underwent gastrotomy. In 20 experimental group rats, the left gastric artery was ligated. Anastomotic bursting pressure and wound hydroxyproline concentration were measured at 3 and 6 days after surgery. Gastrotomy wound bursting pressure at 3 days was significantly higher in control rats (29.5+/-11.8 mm Hg) than in experimental rats (13.5+/-5.5 mm Hg, p<0.001). At 6 days, wound bursting pressure in control rats (81.2+/-14.2 mm Hg) was not significantly higher than in experimental rats (67.4+/-26.9 mm Hg, p<0.17). There were no instances of gastrotomy dehiscence in control rats; dehiscence occurred in two of the experimental animals (p=0.24). Wound hydroxyproline concentration was not significantly different in control and experimental animals. In this rat model of moderate gastric ischaemia, ischaemia reduced the early mechanical strength of gastric anastomoses.