Method and apparatus for invasively measuring cardiac output by detecting temperature differences of blood heated by radiation
US5954659A · kind A · utility
Inventors
Key dates
| Filing date | Feb 16, 1996 |
| Grant date | Sep 21, 1999 |
| Priority date | — |
| Expiry date | Feb 16, 2016 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61B5/028
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
A cardiac output measurement device volumetrically heating a predefined quantity of blood flowing through a heart by arbitrarily applying a containable energy field to the blood using a thermodilution catheter having an emitter that uniformly emits electromagnetic radiation. Blood temperature is measured at the pulmonary artery by a sensor that provides a signal representing the temperature of the mixed blood to a controller. The controller determines the flow rate, or cardiac output, by performing a heat balance analysis based upon the applied power and resultant blood temperature. The cardiac output measurement device includes a catheter having an emitter and, preferably, a temperature sensor located at its distal end. The catheter is coupled to a laser or other energy source capable of generating containable electromagnetic radiation, such as an ultraviolet or microwave energy source. Significantly, for the preferred laser source, the emitter is a diffuser that uniformly emits the laser-generated energy into a predetermined volume of flowing blood. A temperature measuring system of the controller receives temperature signals from the sensor and generates a resultant temporal tem…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.