The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 03, 2000
Filed:
Jul. 23, 1998
Robert Gail Billings, Salt Lake City, UT (US);
Justin S Clark, Salt Lake City, UT (US);
Ke-shieng Yang, Sandy, UT (US);
Jon Neese, Holladay, UT (US);
Allan L Kaminsky, Holladay, UT (US);
Microcor, Inc., Salt Lake City, UT (US);
Abstract
The hematocrit of blood (i.e., the percentage of whole blood volume occupied by red blood cells) perfusing a finger is determined by stimulating the finger with two current frequencies, one relatively high (e.g., 10 MHZ) and the other relatively low (e.g., 100 KHz). Voltages induced in the finger in response to the two current frequencies are then captured and separated into baseline and pulsatile components. The hematocrit is determined as a function of the ratio of the high frequency pulsatile component to the low frequency pulsatile component, multiplied by the ratio of the square of the low frequency baseline component to the square of the high frequency baseline component. The signal-to-noise ratio of the captured voltages can be enhanced by the application of external pressure to the finger, such as by applying a pressure cuff to the finger.