Continuous measurement of cardiac output with the use of stochastic system identification techniques.
The limitations of developing a technique to measure cardiac output continuously are given. Logical explanations are provided for the economic, technical, and physiologic benefits of a stochastic system identification technique for measuring cardiac output. Heat is supplied by a catheter-mounted filament driven according to a pseudorandom binary sequence. Volumetric fluid flow is derived by a cross-correlation algorithm written in the C language. In vitro validation is performed with water in a flow bench. The computed flow (y) compared with the in-line-measured flow (x) yields the linear regression y = 1.024x - 0.157 (r = 0.99). The average coefficient of variation is less than 2% over a volumetric fluid flow range of 2 to 10 L/min.
Yelderman
M
M
InterFlo Medical, Plano, TX 75074.
D000703:Analog-Digital Conversion; D001790:Blood Physiological Phenomena; D001831:Body Temperature / Q000502:physiology; D006328:Cardiac Catheterization; D002302:Cardiac Output / Q000502:physiology; D006358:Hot Temperature; D006801:Humans; D007201:Indicator Dilution Techniques; D008955:Models, Cardiovascular; D008991:Monitoring, Physiologic; D011651:Pulmonary Artery / Q000502:physiology; D012815:Signal Processing, Computer-Assisted; D013269:Stochastic Processes