US5453576A
Expired / Lapsed
US
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Cardiovascular measurements by sound velocity dilution
Assignee: Transonic Systems Inc
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Filing: 1994-10-24
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Granted: 1995-09-26
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Expires: 2014-10-24
Abstract
Abstract An apparatus and method for measuring hemodynamic parameters includes a sound velocity sensor coupled to at least one of an arterial or venous portion of a blood system. An indicator medium is injected into the blood system upstream of the sensor to dilute the bloodstream, and the sensor detects the dilution through changes in measured sound velocity. The changes are recorded and used to determine hemodynamic parameters.
Inventors
- 👤 Nikolai M. Krivitski
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 11:54
CPC Classifications
A; A61; A61B; A61B5/00; A61B5/02; A61B5/026; A61B5/0275; A61M; A61M1/00; A61M1/36; A61M1/3621; A61M1/3653; A61M1/3656; A61M1/3658; A61M1/3659; A61M1/3661; A61M1/14; A61M1/16; A61M1/3669; A61M2205/00; A61M2205/33; A61M2205/3368
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
172 words
Apparatus for measuring blood parameters, comprising: a blood system, having an upstream end and a downstream end and including an arterial portion and a venous portion connected to carry blood between said upstream and said downstream end; a sound velocity sensor coupled to at least one of said arterial and venous portions of said blood system for detecting the velocity of sound in blood flowing within said at least one portion; an injection port in said blood system upstream of said sound velocity sensor; an indicator injectable through said injection port to produce an indicator bolus in blood flowing in said system, said indicator bolus having sound velocity characteristics different from sound velocity characteristics of blood flowing within said blood system in the absence of said indicator to thereby dilute said blood sound velocity characteristics; means responsive to said sensor for detecting said bolus in said bloodstream and for producing and recording curves representing said diluted sound velocity characteristics; and means for determining selected blood characteristics from said sound velocity dilution characteristics.
Claim 2
Dependent Claim
172 words
Apparatus for measuring blood parameters, comprising: a blood system, having an upstream end and a downstream end and including an arterial portion and a venous portion connected to carry blood between said upstream and said downstream end; a sound velocity sensor coupled to at least one of said arterial and venous portions of said blood system for detecting the velocity of sound in blood flowing within said at least one portion; an injection port in said blood system upstream of said sound velocity sensor; an indicator injectable through said injection port to produce an indicator bolus in blood flowing in said system, said indicator bolus having sound velocity characteristics different from sound velocity characteristics of blood flowing within said blood system in the absence of said indicator to thereby dilute said blood sound velocity characteristics; means responsive to said sensor for detecting said bolus in said bloodstream and for producing and recording curves representing said diluted sound velocity characteristics; and means for determining selected blood characteristics from said sound velocity dilution characteristics.
Claim 3
Dependent Claim
26 words
The apparatus of claim 1, further including a sound amplitude sensor connected to at least one of said arterial and venous portions of said blood system.
Claim 4
Dependent Claim
26 words
The apparatus of claim 1, further including an electrical impedance sensor connected to at least one of said arterial and venous portions of said blood system.
Claim 5
Dependent Claim
25 words
The apparatus of claim 1, further including an optical sensor connected to at least one of said arterial and venous portions of said blood system.
Claim 6
Dependent Claim
25 words
The apparatus of claim 1, further including a thermal sensor connected to at least one of said arterial and venous portions of said blood system.
Claim 7
Dependent Claim
38 words
The apparatus of claim 1, wherein said sound sensor is connected to said venous portion of said blood system, and wherein said injection port is in said arterial portion, whereby solution clearance is determinable from said dilution curves.
Claim 8
Dependent Claim
34 words
The apparatus of claim 1, wherein said sound sensor is connected to said arterial portion of said blood system and wherein said injection port is in said venous portion, whereby solution clearance is determinable.
Claim 9
Dependent Claim
24 words
The apparatus of claim 1, wherein said injection port is so located as to cause all of said indicator bolus to pass said sensor.
Claim 10
Dependent Claim
38 words
The apparatus of claim 1, further including a catheter in at least one of said arterial and venous portions of said blood system, said catheter incorporating said sensor and said injection port for intravascular measurement of blood parameters.
Claim 11
Dependent Claim
14 words
The apparatus of claim 9, further including a sound amplitude sensor on said catheter.
Claim 12
Dependent Claim
13 words
The apparatus of claim 10, further including a temperature sensor on said catheter.
Claim 13
Dependent Claim
32 words
The apparatus of claim 11, wherein said catheter is located in said arterial portion of said blood system, and wherein said injection port is in said venous portion of said blood system.
Claim 14
Dependent Claim
14 words
The apparatus of claim 11, further including an electrical impedance sensor on said catheter.
Claim 15
Dependent Claim
13 words
The apparatus of claim 11, further including an optical sensor on said catheter.
Claim 16
Dependent Claim
38 words
The apparatus of claim 1, wherein said blood system includes a blood vessel forming a part of the cardiovascular system of a patient, and wherein said sensor is exterior to said vessel for perivascular measurement of blood parameters.
Claim 17
Dependent Claim
27 words
The apparatus of claim 1, wherein said blood system includes extracorporeal tubing, and wherein said sensor is exterior to said vessel for clamp-on measurement of blood parameters.
Claim 18
Dependent Claim
31 words
The apparatus of claim 1, wherein said sound sensor is coupled to said arterial portion of said blood system and further including a blood flow sensor coupled to said arterial system.
Claim 19
Dependent Claim
19 words
The apparatus of claim 17, wherein said injection port is connected to said venous portion of said blood system.
Claim 20
Dependent Claim
20 words
The apparatus of claim 18, further including a dilution sensor coupled to one of said arterial portion and venous portion.
Claim 21
Dependent Claim
46 words
The apparatus of claim 1, wherein said sound velocity sensor is coupled to said venous portion of said blood system and further including a second sound velocity sensor closely matched to said first-named sound velocity sensor and coupled to said arterial portion of said blood system.
Claim 22
Dependent Claim
34 words
The apparatus of claim 20, further including a first dilution sensor coupled to said arterial portion of said blood system and a second dilution sensor coupled to said venous portion of said blood system.
Claim 23
Dependent Claim
16 words
The apparatus of claim 21, wherein said first and second dilution sensors are electrical impedance sensors.
Claim 24
Dependent Claim
15 words
The apparatus of claim 21, wherein said first and second dilution sensors are optical sensors.
References Cited (Backward Citations)
US3640271A
Cited
US4391124A
Cited
US4434648A
Cited
US4856321A
Cited
US4777958A
Cited
US5230341A
Cited
US5312550A
Cited
US5312550B1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1998-09-25 | 1999-03-27 | 1999-09-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-09-25 | 2003-03-27 | 2003-09-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-09-25 | 2007-03-27 | 2007-09-26 | $7700.00 | Window Closed / Lapsed |