US5247932A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Sensor for intrauterine use
Assignee: Nellcor Puritan Bennett LLC
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Filing: 1991-10-11
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Granted: 1993-09-28
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Expires: 2011-10-11
Abstract
Abstract A sensor placement and retention mechanism for use with fetal sensor sites beyond the user's reach are disclosed. The preferred embodiment of this invention is a fetal pulse oximetry sensor having an active face through which a light source and a light detector operate. The sensor includes a handle that facilitates placement of the active face at a sensor site in a preferred region beyond the transcervical region and beyond the reach of the user. A pair of electrodes--one disposed against the fetus' skin and one exposed to the amniotic fluid--are used to confirm that the sensor is firmly in place on the fetus. In an optional sensor retention feature, a self-inflating bladder presses the active face of the sensor against the fetus' skin to optically couple the sensor with the tissue at the sensor site.
Inventors
- 👤 Christopher Chung
- 👤 Eric Johansson
- 👤 Carl Ritson
- 👤 Paul D. Mannheimer
- 👤 Helen M. McNamara
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 04:51
CPC Classifications
A; A61; A61B; A61B5/00; A61B5/145; A61B5/1455; A61B5/1464; A61B5/14542; A61B5/68; A61B5/6846; A61B5/6847; A61B5/6852; A61B5/6853; A61B5/6885
Claims Analysis
Total Claims: 26
Claim 1
Independent Claim
91 words
A pulse oximetry apparatus for use in measuring a blood characteristic in fetal tissue during labor and delivery, the apparatus comprising: a sensor having an active face including a light source and a light detector; a handle means attached to said sensor for accurately placing the active face of the sensor on a site on a fetus beyond the presenting part and beyond the transcervical region; and a self-inflating bladder means attached to said sensor for retaining the active face of the sensor in place on the site on the fetus.
Claim 2
Dependent Claim
91 words
A pulse oximetry apparatus for use in measuring a blood characteristic in fetal tissue during labor and delivery, the apparatus comprising: a sensor having an active face including a light source and a light detector; a handle means attached to said sensor for accurately placing the active face of the sensor on a site on a fetus beyond the presenting part and beyond the transcervical region; and a self-inflating bladder means attached to said sensor for retaining the active face of the sensor in place on the site on the fetus.
Claim 3
Dependent Claim
22 words
The apparatus according to claim 1 wherein the bladder means has a compressible, self-expanding, foam disposed therein for inflating the bladder means.
Claim 4
Dependent Claim
28 words
The apparatus according to claim 1 wherein the bladder means has an opening disposed on a surface thereof for controlling the rate of self-inflation of the bladder means.
Claim 5
Dependent Claim
13 words
The apparatus according to claim 3 wherein the opening is approximately 0.050 inches.
Claim 6
Dependent Claim
106 words
A pulse oximetry apparatus for use in measuring a blood characteristic in fetal tissue during labor and delivery, the apparatus comprising: a sensor having an active face including a light source and a light detector; a handle means attached to said sensor including a sleeve having a predetermined radius of curvature for accurately placing the active face of the sensor on a site of a fetus beyond the presenting part and beyond the transcervical region; and a rod removably insertable into the sleeve, the rod being constructed so that the radius of curvature of the sleeve is altered when the rod is inserted into the sleeve.
Claim 7
Dependent Claim
106 words
A pulse oximetry apparatus for use in measuring a blood characteristic in fetal tissue during labor and delivery, the apparatus comprising: a sensor having an active face including a light source and a light detector; a handle means attached to said sensor including a sleeve having a predetermined radius of curvature for accurately placing the active face of the sensor on a site of a fetus beyond the presenting part and beyond the transcervical region; and a rod removably insertable into the sleeve, the rod being constructed so that the radius of curvature of the sleeve is altered when the rod is inserted into the sleeve.
Claim 8
Dependent Claim
29 words
The apparatus according to claim 5 wherein the rod is constructed so that the radius of curvature of the sleeve increases when the rod is inserted into the sleeve.
Claim 9
Dependent Claim
26 words
The apparatus according to claim 6 wherein the rod is constructed so that the sleeve is substantially straight when the rod is inserted into the sleeve.
Claim 10
Dependent Claim
23 words
The apparatus according to claim 7 wherein the sleeve comprises approximately 0.020 inch steel, and wherein the rod comprises approximately 0.025 inch steel.
Claim 11
Dependent Claim
121 words
A pulse oximetry apparatus for use in measuring a blood characteristic in fetal tissue during labor and delivery, the apparatus comprising: a sensor having an active face including a light source and a light detector; a handle means attached to said sensor for accurately placing the active face of the sensor on a site of a fetus beyond the presenting part and beyond the transcervical region; and contact determining means for determining whether the active face is placed firmly in contact with the site on the fetus, the contact determining means including: a first electrode disposed on the active face of the sensor; a second electrode; and current generating means for generating current between the first electrode and the second electrode.
Claim 12
Dependent Claim
121 words
A pulse oximetry apparatus for use in measuring a blood characteristic in fetal tissue during labor and delivery, the apparatus comprising: a sensor having an active face including a light source and a light detector; a handle means attached to said sensor for accurately placing the active face of the sensor on a site of a fetus beyond the presenting part and beyond the transcervical region; and contact determining means for determining whether the active face is placed firmly in contact with the site on the fetus, the contact determining means including: a first electrode disposed on the active face of the sensor; a second electrode; and current generating means for generating current between the first electrode and the second electrode.
Claim 13
Dependent Claim
26 words
The apparatus according to claim 9 wherein the second electrode is located on a surface of the sensor other than the active face of the sensor.
Claim 14
Dependent Claim
25 words
The apparatus according to claim 10 wherein the second electrode is located on a surface of the sensor opposite the active face of the sensor.
Claim 15
Dependent Claim
48 words
The apparatus according to claim 9 wherein the contact determining means further comprises impedance measuring means, coupled to the current generating means, for measuring the impedance between the first electrode and the second electrode in accordance with the current flowing between the first electrode and the second electrode.
Claim 16
Dependent Claim
31 words
The apparatus according to claim 12 wherein the contact determining means further comprises threshold comparing means, coupled to the impedance measuring means, for comparing the measured impedance to a threshold value.
Claim 17
Dependent Claim
51 words
The apparatus according to claim 13 wherein the contact determining means further comprises contact indicating means, coupled to the threshold comparing means, for providing a signal when the measured impedance exceeds the threshold value for indicating that the active face is placed firmly in contact with the site on the fetus.
Claim 18
Dependent Claim
26 words
The apparatus according to claim 14 wherein the contact indicating means comprises a visual indicator that is activated when the measured impedance exceeds the threshold value.
Claim 19
Dependent Claim
111 words
The apparatus according to claim 14 further comprising: calculating means for calculating a blood oxygen saturation value; signal communicating means, coupled to the light detector and to the calculating means, for communicating signals corresponding to optical data from the light detector to the calculating means; wherein the calculating means includes saturation calculating means for calculating a blood oxygen saturation value using the signals corresponding to the optical data; and wherein the saturation calculating means is coupled to the contact indicating means for altering the calculation of the blood oxygen saturation value in a predetermined manner when the active face is not placed firmly in contact with the site on the fetus.
Claim 20
Independent Claim
106 words
A method of measuring a blood characteristic in fetal tissue during labor and delivery comprising the steps of: inserting a sensor into a mother's uterus, the sensor having an active face; placing the active face of the sensor on a site on a fetus beyond the presenting part and beyond the transcervical region; calculating the blood characteristic; determining whether the active face of the sensor is placed firmly in contact with the site on the fetus; and altering the calculation of the blood characteristic in a predetermined manner if the active face of the sensor is not firmly in contact with the site on the fetus.
Claim 21
Independent Claim
106 words
A method of measuring a blood characteristic in fetal tissue during labor and delivery comprising the steps of: inserting a sensor into a mother's uterus, the sensor having an active face; placing the active face of the sensor on a site on a fetus beyond the presenting part and beyond the transcervical region; calculating the blood characteristic; determining whether the active face of the sensor is placed firmly in contact with the site on the fetus; and altering the calculation of the blood characteristic in a predetermined manner if the active face of the sensor is not firmly in contact with the site on the fetus.
Claim 22
Dependent Claim
33 words
The method according to claim 17 wherein the determining step comprises the step of causing current flow between a first electrode disposed on the active face of the sensor and a second electrode.
Claim 23
Dependent Claim
40 words
The method according to claim 18 wherein the determining step further comprises the step of measuring the impedance between the first electrode and the second electrode in accordance with the current flowing between the first electrode and the second electrode.
Claim 24
Dependent Claim
23 words
The method according to claim 19 wherein the determining step further comprises the step of comparing the measured impedance to a threshold value.
Claim 25
Dependent Claim
43 words
The method according to claim 20 wherein the determining step further comprises the step of providing a signal when the measured impedance exceeds the threshold value for indicating that the active face is placed firmly in contact with the site on the fetus.
Claim 26
Dependent Claim
27 words
The method according to claim 21 wherein the determining step further comprises the step of activating a visual indicator when the measured impedance exceeds the threshold value.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1996-09-27 | 1997-03-29 | 1997-09-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-09-27 | 2001-03-29 | 2001-09-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-09-27 | 2005-03-29 | 2005-09-28 | $7700.00 | Window Closed / Lapsed |