Kenneth Wayne Craig

US Patent:

48692530, Sep 26, 1989

Filed:

Aug 18, 1986

Appl. No.:

6/897662

Inventors:

Kenneth C. Craig - Bellevue WA
Karl F. Gauglitz - Kirkland WA
G. Michael Losh - Mercer Island WA
Lee R. Mason - Issaquah WA
Richard C. Nova - Kirkland WA
James W. Taylor - Bothell WA
Stephen J. Prosser - Lynnwood WA

Assignee:

Physio-Control Corporation - Redmond WA

International Classification:

A61B 500

US Classification:

128633

Abstract:

The present invention discloses a method and apparatus for indicating perfusion and oxygen saturation trends in oximetry. In transmittance and reflectance oximetry, LEDs (40, 42) are typically employed to expose tissue to light at two different wavelengths. The light transmitted through, or reflected by, the tissue is received by a detector (38) where signals proportional to the intensity of light are produced. These signals are then processed by oximeter circuitry (14, 16) to determine oxygen saturation, pulse rate, and perfusion. Displays (20) are provided including a display (132, 134) of the change in the oxygen saturation during a specified interval. This display may include first (132) and second (134) trend indication displays that indicate when the oxygen saturation has either been increasing or decreasing at a rate in excess of some predetermined level. Preferably, these displays are triangular, upwardly and downwardly directed light-emitting diodes. A digital display (138) of the change in oxygen saturation may also be provided.