Method and apparatus for respiratory gas analysis employing measurement of expired gas mass
US6506608B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Aug 20, 2001 |
| Grant date | Jan 14, 2003 |
| Priority date | — |
| Expiry date | Aug 20, 2021 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T436/207497
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The oxygen and carbon dioxide content of expired respiratory gas is determined by measuring the mass and volume of the expired breath. From the composition of the inspired gas which may either be assumed or measured, the mass of the inspired volume may be determined, and since the inspired and expired breaths contain the same mass of nitrogen, the oxygen and carbon dioxide content of the expired breath may be determined. Measurements of temperature and humidity may be required to account for temperature and humidity changes between the inhalation and the exhalation or the inhaled gas may be adjusted in temperature and humidity to equalize the inhaled and exhaled temperature and humidity conditions. The mass and volume of the expiration and the volume mass of the inhalations are determined by an ultrasonic transit time system and a gas density sensor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.