title: Use of the site of subcutaneous insulin administration for the measurement of glucose in patients with type 1 diabetes.
abstract: OBJECTIVE To simplify and improve the treatment of patients with type 1 diabetes, we ascertained whether the site of subcutaneous insulin infusion can be used for the measurement of glucose. RESEARCH DESIGN AND METHODS Three special indwelling catheters (24-gauge microperfusion [MP] catheters) were inserted into the subcutaneous adipose tissue of subjects with type 1 diabetes (n = 10; all C-peptide negative). One MP catheter was perfused with short-acting insulin (100 units/ml, Aspart) and used for insulin delivery and simultaneous glucose sampling during an overnight fast and after ingestion of a standard glucose load (75 g). As controls, the further two MP catheters were perfused with an insulin-free solution (5% mannitol) and used for glucose sampling only. Plasma glucose was measured frequently at the bedside. RESULTS Insulin delivery with the MP catheter was adequate to achieve and maintain normoglycemia during fasting and after glucose ingestion. Tissue glucose concentrations derived with the insulin-perfused catheter agreed well with plasma glucose levels. Median correlation coefficient and median absolute relative difference values were found to be 0.93 (interquartile range 0.91-0.97) and 10.9%, respectively. Error grid analysis indicated that the percentage number of tissue values falling in the clinically acceptable range is 99.6%. Comparable analysis results were obtained for the two mannitol-perfused catheters. CONCLUSIONS Our data suggest that estimation of plasma glucose concentrations from the glucose levels directly observed at the site of subcutaneous insulin infusion is feasible and its quality is comparable to that of estimating plasma glucose concentrations from glucose levels measured in insulin-unexposed subcutaneous tissue.
authors.affiliation: Department of Internal Medicine, Division of Endocrinology and Nuclear Medicine, Medical University of Graz, Graz, Austria.
authors.forename: Stefan
authors.initials: S
authors.lastname: Lindpointner
authors.forename: Stefan
authors.initials: S
authors.lastname: Korsatko
authors.forename: Gerd
authors.initials: G
authors.lastname: Köhler
authors.forename: Hans
authors.initials: H
authors.lastname: Köhler
authors.forename: Roland
authors.initials: R
authors.lastname: Schaller
authors.forename: Ruthy
authors.initials: R
authors.lastname: Kaidar
authors.forename: Ofer
authors.initials: O
authors.lastname: Yodfat
authors.forename: Lukas
authors.initials: L
authors.lastname: Schaupp
authors.forename: Martin
authors.initials: M
authors.lastname: Ellmerer
authors.forename: Thomas R
authors.initials: TR
authors.lastname: Pieber
authors.forename: Werner
authors.initials: W
authors.lastname: Regittnig
mesh_terms: D000328:Adult; D001786:Blood Glucose / Q000032:analysis*; D001800:Blood Specimen Collection / Q000295:instrumentation / Q000379:methods*; D002408:Catheters, Indwelling; D003922:Diabetes Mellitus, Type 1 / Q000097:blood* / Q000175:diagnosis / Q000188:drug therapy*; D003940:Diagnostic Techniques, Endocrine / Q000295:instrumentation; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D007260:Infusion Pumps; D055104:Infusions, Subcutaneous; D007328:Insulin / Q000008:administration & dosage*; D008297:Male; D008954:Models, Biological; D011379:Prognosis; D013997:Time Factors
chemical_list: D001786:Blood Glucose; D007328:Insulin