Objective: to investigate peripheral metabolism in the leg during bypass surgery for chronic ischaemia.
Patients and methods: in eight patients, microdialysis catheters were placed in the anterior and posterior tibial muscles, subcutaneously in the leg and, for reference, subcutaneously in the pectoral region. Tissue glucose, glycerol and lactate levels were measured between induction of anaesthesia and the first postoperative day.
Results: glucose levels increased postoperatively at all four sites. Glycerol levels decreased during the day of surgery. Glycerol was significantly lower in the leg than in the pectoral region. Muscle lactate increased after anaesthesia, but before proximal clamping, and no further significant intra-operative increase was observed. Post-operatively, lactate decreased to baseline levels. Subcutaneous lactate levels followed the changes observed in muscle but did not reach statistical significance.
Conclusion: bypass surgery for chronic ischaemia temporarily worsens ischaemic metabolism in the leg.