Implications of an intracorporeal glucose sensor in the management of diabetic patients.

Long-term hyperglycemia is the main cause of diabetic late complications (angiopathy, neuropathy). The problem of lifelong management of diabetes is to guarantee near-normal glycemia. Since the introduction of self-monitoring of blood glucose by means of extracorporeal devices on the basis of strips, an important improvement of metabolic management of diabetic patients has become possible. In order to further improve the control of glycemia, the following steps of an evolving system of electrochemical glucose sensing and monitoring should be envisaged: (1) fast-acting extracorporeal glucometers for incidental analyses, (2) intracorporeal sensors for short-term but easily repeated use to follow any kind of open-loop insulin therapy and to provide appropriate hypoglycemia-warning signals, (3) intracorporeal sensors as an essential part of automated feedback-controlled systems for insulin delivery. Approximately 4000 patients per million of the population might benefit from the latter version of intracorporeal glucose sensors. In closed-loop blood glucose control, however, pathophysiological problems may arise from the sole application of negative feedback control in the glucose-insulin algorithm.