Patent · US Expired

Method and apparatus for calculating arterial oxygen saturation based plethysmographs including transients

US5078136A · kind A · utility

269Cited by
6References
14Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 4, 1989
Grant dateJan 7, 1992
Priority date
Expiry dateAug 4, 2009

Classification

  • Technology area (CPC A)Human Necessities
  • CPC primaryA61B5/7207
  • WIPO fieldMedical technology
  • WIPO sectorInstruments

Abstract

A method and apparatus for improving the calculation of oxygen saturation by non-invasive pulse oximeters during transient conditions. Transient conditions introduce artifactual errors into the detected optical signal because of changes in transmittance of the light with localized blood volume changes and as the average background oxygen saturation level of the patient's blood changes. The invention relates to correcting the detected optical pulses by linear interpolation and rate of change techniques or by selective frequency filtering and compensating the detected optical signal using the filtered signal to provide accurate estimates of oxygen saturation during transient conditions.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.