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US3618591A
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Cardiac output determination method for use with dye dilution procedures
Assignee: Individual
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Filing: 1969-04-09
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Granted: 1971-11-09
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Expires: 1989-04-09
Abstract
Abstract The disclosure concerns a method and apparatus for quickly determining the area under a dye dilution curve, based upon triangle congruency, for use in rapid determination of cardiac output.
Inventors
- 👤 Edward C Bradley
- 👤 John W Barr
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 17:32
CPC Classifications
A; A61; A61B; A61B5/00; A61B5/02; A61B5/026; A61B5/0275; G; G06; G06G; G06G1/00; G06G1/02; G06G1/10; G06G1/12
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
97 words
In the method of estimating cardiac output by determining blood flow rate from the heart, the steps that include a. suddenly injecting a quantity I of dye into a body blood flow channel, b. determining the peak concentration PC of the dye flowing in the blood in a body vessel, c. determining the time interval T50 that elapses between the occurrences of approximately 50 percent peak concentrations of the dye during increase and decrease of said dye concentrations in that vessel, and d. obtaining a value for said blood flow as a function of I/PC X T50.
Claim 2
Dependent Claim
97 words
In the method of estimating cardiac output by determining blood flow rate from the heart, the steps that include a. suddenly injecting a quantity I of dye into a body blood flow channel, b. determining the peak concentration PC of the dye flowing in the blood in a body vessel, c. determining the time interval T50 that elapses between the occurrences of approximately 50 percent peak concentrations of the dye during increase and decrease of said dye concentrations in that vessel, and d. obtaining a value for said blood flow as a function of I/PC X T50.
Claim 3
Dependent Claim
82 words
The method of claim 1, wherein said step (d) comprises determining a value for flow in ml./min. by evaluation of the expression 51.4 X I/PC X T50 X CF where I is measured in milligrams PC is measured in millimeters T50 is measured in seconds and CF is a calibration factor correlating recorder output with dye concentration in the blood, and said steps (b) and (c) include detecting and recording the concentration of dye in the blood as a function of time.
References Cited (Backward Citations)
US2289110A
Cited
US2772052A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-11-08 | 1975-05-10 | 1975-11-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-11-08 | 1979-05-10 | 1979-11-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-11-08 | 1983-05-10 | 1983-11-09 | $7700.00 | Window Closed / Lapsed |