High-resolution temperature sensing for cardiovascular monitoring
High-resolution temperature sensing for cardiovascular monitoring
In current clinical practice, thermodilution is used to derive cardiovascular parameters, like cardiac output, to monitor cardiovascular function in patients. A small volume of cold (typically 10 ml of cold (4◦C) saline) is injected into a peripheral or central vein and is than transported to the heart. With a temperature equipped catheter placed in a systemic – or pulmonary artery, a thermal Indicator Dilution Curve (IDC) yields cardiac output.
With the Amazec system using photonic technology with fibre optic sensors based on Fibre Bragg Grating (FBG) technique, high-resolution temperature sensing (fractions of 0.1 milliKelvin) becomes possible. Using photonic technology additional feature extraction from thermodilution curves becomes feasible. This allows reliable measurement of cardiovascular parameters, such as cardiac output and circulating bloodvolume, that can be used to optimize diagnosis and treatments. Note also that, with high-resolution temperature sensing, multiple IDC’s can be measured after one single injection, with the glass-fiber positioned outside the vascular system (e.g. skin over an artery), resulting in minimal invasive, extremely sensitive registrations of thermal events in arteries or the heart after a single injection of cold bolus.
Right image: A thermodilution curve measureed with Amazec’s high resolution temperature probe in an in vitro setup.
Left image: Matlab simulated thermodilution curve with a healthy heart showing multiple recirculations with a sensor on the skin over the radial artery. (Ton Backx)