title: Evaluation of a continuous blood glucose monitoring system using a central venous catheter with an integrated microdialysis function.
abstract: BACKGROUND
  Glycemic control in critically ill patients has been the topic of an interesting debate during the last decade. An accurate continuous glucose monitoring system is essential to better understand this field. This prospective study thus evaluates the accuracy and technical feasibility of a continuous glucose monitoring system using intravascular microdialysis.
  
  
  METHODS
  Thirty patients undergoing cardiac surgery were monitored using a triple-lumen central venous catheter (Eirus TLC; Eirus Medical AB, Solna, Sweden) with an integrated microdialysis function. The catheter functions as a central venous catheter, enabling blood sampling and administration of infusions and medication while simultaneously providing continuous glucose monitoring. The patients were monitored for up to 48 h postoperatively. As reference, arterial blood gas samples were taken every hour and analyzed in a blood gas analyzer.
  
  
  RESULTS
  Six hundred seven paired samples were obtained for analysis. Using Clarke Error Grid analysis, 100% of the paired samples were in Zones A+B, and 97% were in Zone A. Mean difference (bias) was -0.12 mmol/L, and mean absolute relative difference was 5.6%. Of the paired samples, 97.5% were correct according to International Organization for Standardization criteria. Bland-Altman analysis showed bias ± limits of agreement were -0.12 ± 0.7 mmol/L. No hypoglycemic episodes were observed.
  
  
  CONCLUSIONS
  Central venous microdialysis is an accurate and reliable method for continuous blood glucose monitoring up to 48 h in patients undergoing cardiac surgery. With the microdialysis function integrated in a central venous catheter, no extra device for the continuous glucose monitoring is required. The system may be useful in critically ill patients.
authors.affiliation: Section of Cardiothoracic Surgery and Anesthesiology, Department of Molecular Medicine and Surgery, Karolinska Institutet, 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: Öwall
authors.forename: Anders
authors.initials: A
authors.lastname: Franco-Cereceda
authors.forename: Jan
authors.initials: J
authors.lastname: Liska
mesh_terms: D000368:Aged; D001784:Blood Gas Analysis / Q000379:methods*; D001786:Blood Glucose / Q000378:metabolism*; D006348:Cardiac Surgical Procedures; D062905:Central Venous Catheters / Q000706:statistics & numerical data; D016638:Critical Illness; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D007362:Intensive Care Units; D008297:Male; D017551:Microdialysis / Q000295:instrumentation / Q000379:methods*; D008875:Middle Aged; D008991:Monitoring, Physiologic / Q000379:methods*; D019095:Point-of-Care Systems; D011184:Postoperative Period; D011446:Prospective Studies; D013548:Sweden / Q000453:epidemiology
chemical_list: D001786:Blood Glucose