Biomaterial Database

Measurement of cardiac output by earpiece dye-dilution method with automatic calibration of dye concentration. 1977

R Katori, and T Hayashi, and K Kanamasa, and K Ishikawa

A non-invasive method for measuring cardiac output by an earpiece dye densitometer was proposed. The densitometer is dichromatic and has an air capsule to make subject's ear bloodless by inflation, so that it can calibrate indocyanine green dye concentration without blood sampling. Duplicate measurements of cardiac output showed a good agreement in 40 cases (r = 0.97, standard deviation (S.D.) = 8.9%), which was comparable to the result of the cuvette method (r = 0.98, S.D. = 8.1%). Simultaneous measurements of cardiac output by the earpiece method (x) and the standard cuvette method (y) revealed a good agreement (r = 0.91, y = 0.96x+0.34, S.D. = 16.4%) in 52 measurements of 25 cases. A similarly good correlation was obtained between the two methods during ergometer exercise in supine position in 5 cases. These suggest that this earpiece dye-dilution method is reliable for cardiac output measurement and advantageous for clinical use because of non-invasive technique.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D008433	Mathematics	The deductive study of shape, quantity, and dependence. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)	Mathematic
D008954	Models, Biological	Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.	Biological Model,Biological Models,Model, Biological,Models, Biologic,Biologic Model,Biologic Models,Model, Biologic
D002302	Cardiac Output	The volume of BLOOD passing through the HEART per unit of time. It is usually expressed as liters (volume) per minute so as not to be confused with STROKE VOLUME (volume per beat).	Cardiac Outputs,Output, Cardiac,Outputs, Cardiac
D003720	Densitometry	The measurement of the density of a material by measuring the amount of light or radiation passing through (or absorbed by) the material.	Densitometries
D004395	Dye Dilution Technique	Method for assessing flow through a system by injection of a known quantity of dye into the system and monitoring its concentration over time at a specific point in the system. (From Dorland, 28th ed)	Dye Dilution Technic,Dilution Technic, Dye,Dilution Technics, Dye,Dilution Technique, Dye,Dilution Techniques, Dye,Dye Dilution Technics,Dye Dilution Techniques,Technic, Dye Dilution,Technics, Dye Dilution,Technique, Dye Dilution,Techniques, Dye Dilution
D004423	Ear	The hearing and equilibrium system of the body. It consists of three parts: the EXTERNAL EAR, the MIDDLE EAR, and the INNER EAR. Sound waves are transmitted through this organ where vibration is transduced to nerve signals that pass through the ACOUSTIC NERVE to the CENTRAL NERVOUS SYSTEM. The inner ear also contains the vestibular organ that maintains equilibrium by transducing signals to the VESTIBULAR NERVE.	Vestibulocochlear System,Vestibulocochlear Apparatus,Apparatus, Vestibulocochlear,Ears,System, Vestibulocochlear
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000328	Adult	A person having attained full growth or maturity. Adults are of 19 through 44 years of age. For a person between 19 and 24 years of age, YOUNG ADULT is available.	Adults