THE ULM-ZUCKER-UHR-SYSTEM AND ITS CONSEQUENCES

The ''Ulm Zucker Uhr System'' comprises a microdialysis probe, a biose nsor (Glucosensor Unitec Ulm s.c.), a sender transferring telemetrical ly the glucose concentrations, and a receiving indicator. The ''Zucker Uhr'' or ''Sugar Watch'' looks and operates like a normal wrist watch . We now present the functioning pre-prototype of the first portable s ystem, which 1) is continuously measuring in s.c. tissue the Tissue Gl ucose (TG.) concentration in the intercellular fluid on-line enzymatic ally by combining an enzymatic and an electrochemical (amperometric) t echnique, 2) is transferring in the patient via the ''Zucker Uhr'' onc e per minute the actual tissue glucose concentration, i.e. 1,440 value s/24 hours or even 2880 values/48 hours, 3) is actually alarming the p atient by optical and acoustic means, when the tissue glucose is too h igh (hyperglycemia) or too low (hypoglycemia), 4) is storing digitally all values and, therefore, permitting the dialogue between doctor and patient as to his diabetes control in view of his 24 h glucose profil e, which is visual on a computer screen. The advantage for the patient is on the one hand the elimination of the multiple pricking in the fi nger tips for providing capillary blood, and on the other hand, permit ting the preview of the limitation and perhaps the complete eliminatio n of the microangiopathy of the retina, kidneys and nervous system. Th e trend of the T.G. decreases is readily recognizable, which indicates immediately the dangerous hypoglycemia. Likewise, over 48 hours, the hyperglycemic periods are transmitted and recorded which are not measu red and reflected by the Hb(A1) and HbA(1c) conventional measurements. The three periods of development of the system are seen in 1) the pro viding of complete information as to the T.G. profile under conditions of daily life (on-line home monitoring), with ready warning before hy poglycemia, and at the same time permitting the complete control of th e sugar metabolism actually and as documentation, 2) the partial regul ation in the control of the insulin infusion via pumps by the sugar pr ofile in the tissue, and 3) the complete glucose controlled insulin in fusion in a portable device, which contains the sensor and the insulin pump. Problems still exist regarding the self-implantable microdialys is probe and the provision of electrical energy, independent from the network for 24-48 hours, the calibration operated by the patient himse lf, and the miniaturization of the whole system.