title: Real-Time Monitoring of Critical Care Analytes in the Bloodstream with Chemical Sensors: Progress and Challenges.
abstract: We review approaches and challenges in developing chemical sensor-based methods to accurately and continuously monitor levels of key analytes in blood related directly to the status of critically ill hospitalized patients. Electrochemical and optical sensor-based technologies have been pursued to measure important critical care species in blood [i.e., oxygen, carbon dioxide, pH, electrolytes (K(+), Na(+), Cl(-), etc.), glucose, and lactate] in real-time or near real-time. The two main configurations examined to date for achieving this goal have been intravascular catheter sensors and patient attached ex vivo sensors with intermittent blood sampling via an attached indwelling catheter. We discuss the status of these configurations and the main issues affecting the accuracy of the measurements, including cell adhesion and thrombus formation on the surface of the sensors, sensor drift, sensor selectivity, etc. Recent approaches to mitigate these nagging performance issues that have prevented these technologies from clinical use are also discussed.
authors.affiliation: Department of Biomedical Engineering, Michigan Technological University, Houghton, Michigan 49931-1295; email: mcfrost@mtu.edu.
authors.forename: Megan C
authors.initials: MC
authors.lastname: Frost
authors.forename: Mark E
authors.initials: ME
authors.lastname: Meyerhoff
mesh_terms: D015374:Biosensing Techniques / Q000379:methods*; D001774:Blood Chemical Analysis / Q000295:instrumentation*; D003422:Critical Care; D006801:Humans; D008991:Monitoring, Physiologic / Q000295:instrumentation*
keywords: carbon dioxide; electrolytes; ex vivo sensors; glucose/lactate; in vivo sensors; oxygen; pH