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:
Feb. 26, 1991
Filed:
Sep. 01, 1989
Stephen R Ash, Lafayette, IN (US);
Terrance G Echard, West Lafayette, IN (US);
Ash Medical System, Incorporated, West Lafayette, IN (US);
Abstract
Method and apparatus for determining the flow rate of blood passing between a patient and an extracorporeal therapy instrument. The flow measurement apparatus includes a delivery unit for producing a saline bolus interface at a first position of a measurement channel having a predetermined volume between the first and second position. A sensor unit included in the apparatus detects the saline bolus interface as it passes the second position in the channel. An output signal from the sensor unit along with an indication of the production of the saline bolus interface is utilized by a control unit to determine the blood flow rate. The control unit of the apparatus utilizes instantaneous and average blood flow algorithms to calculate instantaneous and average blood flow rates based on the time interval associated with the production of the saline bolus interface and its progression to a predetermined position in the measurement channel. Successive interfaces are also produced in the blood flow to derive an average blood flow rate.