SERUM ENZYME LEVELS DURING INTESTINAL ISCHEMIA

Because the intestinal mucosa is most sensitive to ischemia, serum levels of mucosal enzymes, such as diamine oxidase, may be most likely to indicate intestinal ischemia. Our aim was to compare serum levels of mucosal (diamine oxidase, alkaline phosphatase) and seromuscular (creatinine phosphokinase, lactic dehydrogenase, serum glutamic oxaloacetic transminase) enzymes during intestinal ischemia of varying extent and duration in dogs. Group 1 (n = 6) underwent sham laparotomy. Group 2 (n = 8) had 50% of the small intestine devascularized. Group 3 (n = 8) had the superior mesenteric artery occluded for 2 hours and released. Group 4 (n = 8) had the superior mesenteric artery ligated. Serum samples were obtained before and 2,4,8, and 24 hours after operation, and histologic specimens were examined at 4 hours. Creatinine phosphokinase levels became elevated within 4 hours of ischemic injury in group 2 (223 ± 197 vs. 68 ± 26, p < 0.05) and group 4 (212 ± 136 vs. 76 ± 29, p < 0.05). Significant elevation of serum enzymes levels, except diamine oxidase, occurred in groups 2, 3, and 4 at 24 hours, including those with normal histology after temporary superior mesenteric artery occlusion. Thus seromuscular enzymes, particularly creatinine phosphokinase, were more likely to be elevated during intestinal ischemia. Enzyme levels were not influenced by the extent and reversibility of the ischemic injury.