Validation of intramural intestinal microdialysis as a detector of intestinal ischaemia.

摘要

BACKGROUND: The purpose of this study was to validate intestinal microdialysis as a detector of intestinal ischaemia using measurements of glucose, lactate and glycerol from the jejunal wall. METHODS: Based on a previous study, the cut-off levels for the presence of regional intestinal ischaemia were defined for microdialysis glucose, lactate, glycerol and the lactate/glucose ratio. Changes of 60% in the metabolic compounds measured after 100 min were defined as the cut-off level for ischaemia. The cut-off levels were tested in a randomized, single-blinded study. Ten pigs were used; occlusive ischaemia was performed by clamping a segment of the mesentery to the intestine. Four catheters were inserted per pig, two in the ischaemic segment and two in the non-ischaemic segment. All catheters were numbered, randomly allocated and inserted in the intestine by the staff at the institute and unknown to the investigators. RESULTS: One pig was excluded because the clamping was insufficient. Technical problems with the catheters were registered in 15% of cases owing to damage of the microdialysis membrane, dislocation, or incorrect placement. The predictive values of presence of ischaemia for glucose, lactate, glycerol and the lactate/glucose ratio were: 0.91, 1,0.85 and 0.92, respectively. CONCLUSION: Using a 60% cut-off limit measured after 100 min, intestinal ischaemia can be detected and excluded using intestinal microdialysis, but some technical problems remain that need further investigation.