title: A novel automated discontinuous venous blood monitoring system for ex vivo glucose determination in humans.
abstract: Intensive insulin therapy reduces mortality and morbidity in critically ill patients but imposes great demands on medical staff who must take frequent blood samples for the determination of glucose levels. A solution to this resourcing problem would be provided by an automated blood monitoring system. The aim of the present clinical study was to evaluate such a system comprising an automatic blood sampling unit linked to a glucose biosensor. Our approach was to determine the correlation and system error of the sampling unit alone and of the combined system with respect to reference levels over 12h in humans. Two venous cannulae were inserted to connect the automatic and reference systems to the subjects. Blood samples were taken at 15 and 30 min intervals. The median Pearson coefficient of correlation between manually and automatically withdrawn blood samples was 0.982 for the sampling unit alone and 0.950 for the complete system. The biosensor had a linear range up to 20 mmoll(-1) and a 95% response time of <2 min. Clark Error Grid analysis showed that 96.93% of the data (228 data pairs) was in zone A and 3.07% in zone B. Insulin Titration Error Grid analysis suggested an acceptable treatment in 99.56% of cases. Implementation of a "Keep Vein Open" saline infusion into the automated blood sampling system reduced blood withdrawal failures through occluded catheters fourfold. In summary, automated blood sampling from a peripheral vein coupled with automatic glucose determination is a promising alternative to frequent manual blood sampling.
authors.affiliation: Joanneum Research Forschungsgesellschaft mbH, Institute of Medical Technologies and Health Management, Elisabethstrasse 11a, 8010 Graz, Austria.
authors.forename: R
authors.initials: R
authors.lastname: Schaller
authors.forename: F
authors.initials: F
authors.lastname: Feichtner
authors.forename: H
authors.initials: H
authors.lastname: Köhler
authors.forename: M
authors.initials: M
authors.lastname: Bodenlenz
authors.forename: J
authors.initials: J
authors.lastname: Plank
authors.forename: A
authors.initials: A
authors.lastname: Wutte
authors.forename: J K
authors.initials: JK
authors.lastname: Mader
authors.forename: M
authors.initials: M
authors.lastname: Ellmerer
authors.forename: R
authors.initials: R
authors.lastname: Hellmich
authors.forename: H
authors.initials: H
authors.lastname: Wedig
authors.forename: R
authors.initials: R
authors.lastname: Hainisch
authors.forename: T R
authors.initials: TR
authors.lastname: Pieber
authors.forename: L
authors.initials: L
authors.lastname: Schaupp
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation*; D001774:Blood Chemical Analysis / Q000295:instrumentation* / Q000379:methods; D001786:Blood Glucose / Q000032:analysis*; D002404:Catheterization / Q000295:instrumentation* / Q000379:methods; D004867:Equipment Design; D019544:Equipment Failure Analysis; D017022:Flow Injection Analysis / Q000295:instrumentation* / Q000379:methods; D006801:Humans; D018962:Phlebotomy / Q000295:instrumentation* / Q000379:methods; D015203:Reproducibility of Results; D012371:Robotics / Q000295:instrumentation*; D012680:Sensitivity and Specificity
chemical_list: D001786:Blood Glucose