title: Evaluation of a continuous blood glucose monitoring system using central venous microdialysis.
abstract: BACKGROUND
  Glycemic control in critically ill patients has been shown to be beneficial. In this prospective study, we evaluated the accuracy and technical feasibility of a continuous glucose monitoring system using intravascular microdialysis.
  
  
  METHODS
  Fifty patients undergoing cardiac surgery were monitored using a 4 Fr intravenous microdialysis catheter (Eirus SLC™, Dipylon Medical AB, Solna, Sweden) percutaneously placed with the tip of the catheter positioned in the superior vena cava. The catheter was connected to the Eirus™ monitoring system, and the patients were monitored for up to 48 h postoperatively in the intensive care unit (ICU). As reference, arterial blood samples were taken every hour and analyzed in a blood gas analyzer.
  
  
  RESULTS
  Data were available from 48 patients. A total of 994 paired (arterial blood gas microdialysis) samples were obtained. Glucose correlation coefficient (R2) was 0.85. Using Clarke error grid analysis, 100% of the paired samples were in region AB, and 99% were in region A. Mean glucose level was 8.3 mmol/liter (149 mg/dl), mean relative difference was 0.2%, and mean absolute relative difference was 5%. A total of 99.2% of the paired samples were correct according to International Organization for Standardization (ISO) criteria. Bland-Altman analysis showed that bias ± limits of agreement were 0.02 ± 1.1 mmol/liter (0.36 ± 20 mg/dl).
  
  
  CONCLUSIONS
  Central venous microdialysis using the Eirus monitoring system is a highly accurate and reliable method for continuous blood glucose monitoring up to 48 h in ICU patients undergoing cardiac surgery. The system may thus be useful in critically ill ICU patients.
authors.affiliation: Department of Molecular Medicine and Surgery, Karolinska Institutet, Section of Cardiothoracic Surgery and Anaesthesiology, Karolinska University Hospital, Stockholm, Sweden. fanny.schierenbeck@ki.se
authors.forename: Fanny
authors.initials: F
authors.lastname: Schierenbeck
authors.forename: Anders
authors.initials: A
authors.lastname: Franco-Cereceda
authors.forename: Jan
authors.initials: J
authors.lastname: Liska
mesh_terms: D000368:Aged; D001786:Blood Glucose / Q000032:analysis*; D006348:Cardiac Surgical Procedures; D062905:Central Venous Catheters; D016638:Critical Illness; D005260:Female; D006801:Humans; D008297:Male; D017551:Microdialysis / Q000295:instrumentation* / Q000379:methods*; D008991:Monitoring, Physiologic / Q000295:instrumentation* / Q000379:methods*
chemical_list: D001786:Blood Glucose