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. 26, 1999
Filed:
May. 01, 1998
Michael J Higgins, Trabuco Canyon, CA (US);
Luong N Phan, Laguna Nigel, CA (US);
Baxter International Inc., Deerfield, IL (US);
Abstract
A system for measuring biological functions of a patient, such as cardiac output, filters noise from a signal provided by a thermistor catheter inserted into the body of the patient. A signal-conditioning cable is disposed between the catheter and an instrument which processes the signal to measure cardiac output. The cable includes circuitry which forms, in combination with a thermistor of the catheter, a low-pass filter for attenuating thermal and high-frequency noise from the signal provided to the instrument. The instrument can more accurately measure cardiac output with the filtered signal than with an unfiltered signal. Although the circuitry which forms the low-pass filter may be combined with the catheter or the instrument, it is preferred to dispose the circuitry in a separate cable to reduce manufacturing costs of the catheter and retrofitting costs of existing instruments.