US5964703A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Extravasation detection electrode patch
Assignee: ACIST Medical Systems Inc
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Filing: 1997-10-24
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Granted: 1999-10-12
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Expires: 2017-10-24
Abstract
Abstract A medical extravasation device has an electrode patch that can attach to the skin for sensing electrical information. Tissue impedance is calculated from the electrode patch signals. The patch has elongate pick-up electrodes inboard of elongate energizing electrodes. The measuring zone determined by the elongate space between the pick-up electrodes enhances sensitivity and specificity. The presence of an extravasation is determined by interpreting the tissue impedance measurement. The method for determining the extravasation includes a first step of determining a pre-injection baseline measurement of the tissue impedance. Then, the tissue impedance is monitored during the procedure itself. A predetermined amount of change in tissue impedance is determined to indicate an extravasation.
Inventors
- 👤 Jack Goodman
- 👤 Arthur Zimmet
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 15:56
CPC Classifications
A; A61; A61B; A61B5/00; A61B5/05; A61B5/053; A61B5/0535; A61M; A61M5/00; A61M5/14; A61M5/168; A61M5/16831; A61M5/16836
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
212 words
An electrode patch for use in a non-invasive device for detecting extravasation that may occur when a needle with a tip is inserted into a patient in order to introduce fluid into the vascular system of a patient, comprising: a body of the patch adapted to be affixed to the skin of a patient, an outer pair of elongated electrodes and an inner pair of elongate electrodes, the length of each of said electrodes being deployed along the body of said patch, said inner pair of electrodes being spaced from one another on either side of a center line, said inner pair defining a measuring zone, said measuring zone being shaped and dimensioned to encompass a needle tip within said zone, said zone being small enough to optimize sensitivity, said inner pair being long enough to facilitate placement of the patch over a needle tip inserted into a patient, each of said outer pair of electrodes being outward, relative to said center line, of a respective one of said inner electrodes, energization of said outer electrodes, when said patch is affixed to the skin of a patient, providing a field which induces a signal in said inner electrodes that is a function of the impedance of the tissue in said measuring zone.
Claim 2
Dependent Claim
212 words
An electrode patch for use in a non-invasive device for detecting extravasation that may occur when a needle with a tip is inserted into a patient in order to introduce fluid into the vascular system of a patient, comprising: a body of the patch adapted to be affixed to the skin of a patient, an outer pair of elongated electrodes and an inner pair of elongate electrodes, the length of each of said electrodes being deployed along the body of said patch, said inner pair of electrodes being spaced from one another on either side of a center line, said inner pair defining a measuring zone, said measuring zone being shaped and dimensioned to encompass a needle tip within said zone, said zone being small enough to optimize sensitivity, said inner pair being long enough to facilitate placement of the patch over a needle tip inserted into a patient, each of said outer pair of electrodes being outward, relative to said center line, of a respective one of said inner electrodes, energization of said outer electrodes, when said patch is affixed to the skin of a patient, providing a field which induces a signal in said inner electrodes that is a function of the impedance of the tissue in said measuring zone.
Claim 3
Dependent Claim
51 words
The patch of claim 1 wherein each of said electrodes further includes a first portion which is relatively short as compared to said elongate portion of each electrode, said relatively short first portions of said electrodes define a coupling region which can be connected to a single clip containing electrical contacts.
Claim 4
Dependent Claim
38 words
The patch of claim 1 wherein each of said elongate electrodes are substantially the same length and wherein each of said outer pair of electrodes is adjacent to and spaced from one of said inner pair of electrodes.
Claim 5
Dependent Claim
71 words
The patch of claim 3 wherein each of said elongate electrodes has a total length of about 3 inches, and a width of about 3/16th of an inch, and wherein said inner pair of electrodes is spaced apart by about 0.75 inches and said outer pair of electrodes is spaced apart by about 1.5 inches, and where said inner pair of electrodes is centralized relative to said outer pair of electrodes.
Claim 6
Dependent Claim
20 words
The patch of claim 4 wherein said body is about two inches in width and about three inches in length.
Claim 7
Dependent Claim
12 words
The patch of claim 1 wherein said electrodes are silver/silver chloride strips.
References Cited (Backward Citations)
US4010749A
Cited
US4534756A
Cited
US4729385A
Cited
US4898576A
Cited
US4743228A
Cited
US4877034A
Cited
US5353802A
Cited
US5246008A
Cited
US5334141A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2002-10-11 | 2003-04-12 | 2003-10-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-10-11 | 2007-04-12 | 2007-10-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-10-11 | 2011-04-12 | 2011-10-12 | $7700.00 | Window Closed / Lapsed |