Apparatus and method for measuring cardiac output
US5423326A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 14, 1993 |
| Grant date | Jun 13, 1995 |
| Priority date | — |
| Expiry date | May 14, 2013 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61B5/7257
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
The present invention reliably computes cardiac output with a noninvasive procedure. The system measures the electrical impedance of a patient's body, during a time interval of interest. The system then obtains frequency transforms of various time segments of the first derivative of the impedance signal. Each such transform is integrated over a frequency range of interest, and the values of the integrals are plotted as a function of time. The graph so derived has characteristic extrema which can be used to identify critical points in the impedance derivative signal. These critical points can be used to determine parameters which are used in a calculation of stroke volume and cardiac output.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.