Search Images Maps Play YouTube News Gmail Drive More »
Sign in
Screen reader users: click this link for accessible mode. Accessible mode has the same essential features but works better with your reader.

Patents

  1. Advanced Patent Search
Publication numberUS3273559 A
Publication typeGrant
Publication dateSep 20, 1966
Filing dateAug 28, 1963
Priority dateAug 28, 1963
Publication numberUS 3273559 A, US 3273559A, US-A-3273559, US3273559 A, US3273559A
InventorsEvans Henry Lee
Original AssigneeConductron Corp
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Method and apparatus for monitoring the approach of birth
US 3273559 A
Abstract  available in
Images(1)
Previous page
Next page
Claims  available in
Description  (OCR text may contain errors)

H. L. EVANS Sept. 20, 1966 METHOD AND APPARATUS FOR MONITORING THE APPROACH OF BIRTH Filed Aug. 28, 1965 R Z 0 8% M J 4 %06 R W %IIMMMT$ k i m z "KL M M T:

M0 /o R A 4 .0 H4

INVENTOR.

#549 if il /9N5 BY M, M

United States Patent 3,273,559 METHOD AND APPARATUS FOR MONITORING THE APPROACH OF BIRTH Henry Lee Evans, Ann Arbor, Micln, assignor to Conductron Corporation, Ann Arbor, Mich, a corporation of Delaware Filed Aug. 28, 1963, Ser. No. 305,149 7 Claims. (Cl. 128-2) This invention relates to a monitoring device and has more particularly to do with a device for monitoring the dilatation of the female cervix during labor and just prior to the actual birth of an infant. The device is so arranged that it eliminates the necessity for the attending physician making personal manual examination of the dilatation from time to time. Thus, it assists materially in contributing to the comfort of the mother during the final hours of labor and also provides a continuous indication of dilatation which assists in the avoidance of complications associated with precipitous birth that may occur during the time between the examinations by the physiclan.

It is common practice in the treatment of expectant mothers to judge the time of birth by the so-called expan sion or dilatation of the cervix and the present invention relates to a measuring means which can, without discomfort to the patient, be observed in a suitable instrument near the patient.

It is a further object to provide a means for suitably mounting monitoring devices which requires a minimum of equipment and discomfort to the patient.

Other objects and features of the invention relating to details of construction and operation will be apparent in the following description and claims.

Drawings accompany the disclosure and the various views thereof may be briefly described as:

FIGURE 1 illustrates a circuit diagram in block form showing the various elements of the apparatus.

FIGURE 2 illustrates the monitoring elements.

FIGURE 3 is a view showing the manner in which the monitoring elements are mounted on the lips of the cervix.

FIGURE 4 is a sectional view of the mounting clip taken on line 4-4 of FIGURE 5.

FIGURE 5 is a sectional view -of a mounting clip taken on line 5-5 of FIGURE 4.

In the female anatomy, the uterus or womb positioned above the vaginal cavity has a lower half or neck portion which is called the cervix. This is the area of the opening of the womb; and, during pregnancy, as child birth approaches, this opening gradually enlarges or dilates and the degree of dilatation is indicative of the descent of the child toward the cervical opening. The womb opening has lip portions referred to at and 12 in FIG- URE 3 in spaced relation, and on these lip portions are mounted expansion clips 14 and 16 having bifurcate gripping portions 18 pivoted at 20 with actuating handle portions 22 which are provided with re-entrant curved portions 24 to permit gripping and handling by forceps shown diagrammatically at 26. The bifurcate gripping portions 18 are provided with small projections in the form of teeth 28 to insure a firm location on the lip of the cervix. The nature of this portion of the body is such that these clips may be applied without discomfort to the patient.

A suitable coil spring 30 serves to hold the portions 18 in gripping relation and these parts are all made of a corrosion resistant material such as stainless steel which can be suitably sterilized. A small open-ended cylinder 32 is supported by apertured ears 34 on a transverse pivot pin 36 which serves as a pivot for the opposed portions of the clips 14 and and also as a location for the spring 30. The cylinder 32 is provided to carry the monitoring devices which form a part of the indicator circuit. These devices can consist of cylindrically shaped capsules 40 and 42 as shown in FIGURE 2. One capsule 40 can carry what is called a ferrite load and the dimension of this capsule can be approximately .5 centimeter in diameter and 1.5 centimeters in length. This ferrite load can be in the nature of a small cylinder of ferrite material in sintered form, for example, which has the properties of ferrite required in the circuit to be described, i.e., a high permeability or high Q rating. The capsule 42 can contain a miniaturized Hartley oscillator using a transistor as the active element with a coaxial output lead wire 44, this capsule being approximately .5 centimeter in diameter and 2 centimeters in length.

The tuned LC tank circuit of the oscillator is the heart of the device because it is in effect the measuring element and it includes an air-wound inductance in capsule 42 and the high permeability or high Q ferrite core in capsule 40. The combined inductance of the air core plus the ferrite determines, in conjunction with a fixed capacitor in the tank circuit, the frequency of oscillation of the Hartley oscillator circuit.

The ferrite 49 is attached by clip 14 to one of the cervical lips 10 and the air core 42 is attached by clip 16 to the other lip 12 as shown in FIGURE 3, the two units being initially adjacent and in close proximity with one another in the normal undilated condition of the cervix. As the two units are separated by dilatation, the inductance of the combination will decrease, and the frequency of oscillation will increase. The change of frequency in the output signal of the oscillator can be readily determined as a function of the known displacement of the two units and a separation indicator can be coupled to the oscillator output by suitable circuitry as described hereinafter to visually indicate the progress of the dilatation. The co-axial cable 44 will connect the active unit 42 inside the mother with the external telemetering equipment but it will be seen that only the slender coaxial cable 44 need extend through the Vagina and that there is no electrical wiring connection whatsoever between the two elements 40 and 42.

Cable 44 will carry direct current to the transistor and serve as the output lead to transmit the oscillator frequency to the counting device. The co-axial cable offers the advantage of a noise shielded signal path and small size, for example, 2 mms. diameter. It can be covered with an insert material, such as, for example, rayolin NF, which is stable from negative 55 to degrees centigrade, and thus lends itself to easy sterilization.

The output of the oscillator is fed to a waveshaping circuit to generate well-defined zero crossings of the output frequency, and this signal will in turn drive a monostable multivibrator. The output pulse amplitude will be constant, and the duration of the pulse less than the highest expected frequency. If the average value of the train of pulses is determined, it is found to be proportional to the input frequency, and this average value can be displayed on a meter calibrated to indicate displacement.

In FIGURE 1, the ferrite load 40' is shown in spaced relation to the Hartley oscillator 42 which is connected by the coaxial cable 44 to a waveshaper 46 having a suitable direct current supply. The waveshaper is connected to the monostable multivibrator 48 and this is connected to a separation indicator 50 of a visual nature, such as a needle or a dial.

The units used internally of the patient are preferably mechanically stabilized by encapsulation in irradiated polyolefin which can be heat shrunk to provide maximum holding of the elements without any volatile glues or solvents. The units will then be dip coated in a heat curable latex compound to provide a smooth closed cell surface that can be easily modified to expose the holding attachments and still provide a sealed capsule that can be sterilized prior to insertion. The co-axial cable cover also bonds well to latex and as previously indicated, can be sterilized. The output cable 44 may have a convenient quick disconnect plug at a suitable location exterior to the patient so that she may disconnect it from the indicator mechanism and move about if necessary.

What is claimed is:

1. A system for indicating the approach of childbirth in a female mammal comprising an electrical circuit including first and second elements physically and mechanically independent of each other adapted for insertion in the vaginal cavity of the female and co-operable electrically with each other to control a measurable parameter of said circuit as a function of the proximity of said elements to each other, means associated with said elements adapted to removably attach said first element to one lip of the cervical opening of the female and said second element to the other lip with no physical or mechanical association between the elements, and telemetering means located externally of the female and coupled to said electrical circuit for translating varia- :ions in said parameter into a signal for indicating the spacing of said cervical lips from each other.

2. A method for monitoring the imminent approach of :hildbirth in a female mammal comprising the steps of attaching a magnetically permeable element to one lip 3f the cervical opening of the female, attaching an in- :luctor element to the other lip of said opening, said elernents being physically and mechanically independent of each other, passing an electrical current through said inductor to generate a magnetic field encompassing said :lement in all positions of said lips, and translating :hanges in the inductance of said inductor caused by changes in the proximity of said element to said inductor into an electrical signal indicative of the spacing of said lips from each other.

3. A method for monitoring the imminent approach of childbirth in a female mammal which comprises the steps of associating, with the spaced lips of the cervix, first and second elements of an electrical inductance :ircuit co-operable with each other but physically detached from each other to control a measurable param- :ter of said circuit as a function of the proximity of said elements to each other and coupling in said circuit a telemetering means located externally of the body for translating variations in said parameter into a signal for indicating the spacing of said cervical lips.

4. An apparatus for indicating the approach of childbirth in a female mammal which comprises resiliently expandable clamping means for attachment to the opposed cervical lips of the female, means on said clamping means remotely operable manually to permit attachment and detachment, first and second elements adapted for insertion into the vaginal cavity carried respectively by said clamping means and physically independent of each other, an electrical circuit incorporating said elements to create a measurable parameter as a function of the proximity of said elements to one another, and telemetering means located externally of the female and coupled to said electrical circuit for translating variations in said parameter into a signal for indicating the spacing of said cervical lips from each other.

5. A device as defined in claim 4 in which only one of said elements is physically connected in said circuit.

6. A device as defined in claim 4 in which each of said elements is encapsulated in a waterproof, relatively inert material to permit sterilization.

'7. A device as defined in claim 4 in which said clamping means each comprise jaw-like members pivoted to each other, spring means to bias said members toward each other, and opposed extensions on said members to permit manipulation thereof to a proper clamping position.

References Cited by the Examiner UNITED STATES PATENTS 2,239,330 4/1941 Lorand 128-2 2,652,825 9/1953 Rauh 128Z 2,831,478 4/1958 Uddenberg 1282 2,824,220 2/1960 Von Micsky l28361 FOREIGN PATENTS 17,220 9/1900 Great Britain.

RICHARD A. GAUDET, Primary Examiner.

LOUIS R. PRINCE, Examiner.

S. BRODER, Assistant Examiner.

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US2239330 *Feb 11, 1938Apr 22, 1941Lorand SandorRecording device
US2652825 *Dec 9, 1949Sep 22, 1953Elmer M RauhMedical diagnostic instrument
US2824220 *Nov 25, 1953Feb 18, 1958Aeronautical Comm Equipment InRadio transmitter tuner
US2831478 *Oct 31, 1955Apr 22, 1958Thoren Herbert AlfredApparatuses for observing and measuring of pressures within organs of the human body
GB190017220A * Title not available
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3583389 *Jun 25, 1968Jun 8, 1971Ndch & CoMethod of detecting approaching birth in mammals
US3905356 *May 15, 1974Sep 16, 1975Edward N DuranSubminiature insertable force transducer
US3940803 *May 6, 1974Mar 2, 1976Battelle Memorial InstituteMethod and system for control of a powered prosthetic device
US4028687 *Sep 8, 1975Jun 7, 1977Matsushita Electric Industrial Co., Ltd.Method and apparatus for delivery alarm for livestock animals
US4141345 *Jan 5, 1977Feb 27, 1979National Research Development CorporationCervical dilation measurement instruments
US4141349 *Nov 3, 1976Feb 27, 1979Agence Nationale De Valorisation De La Recherche (Anvar)Process and device for the in vivo measurement of bone consolidation
US4217575 *Feb 28, 1978Aug 12, 1980Rene LoretteParturition warning devices
US4232686 *Feb 2, 1978Nov 11, 1980Kammlade Jr William GMethod and apparatus for indicating the onset of parturition
US5279309 *Jul 27, 1992Jan 18, 1994International Business Machines CorporationSignaling device and method for monitoring positions in a surgical operation
US5402801 *Apr 28, 1994Apr 4, 1995International Business Machines CorporationSystem and method for augmentation of surgery
US5445166 *Apr 6, 1994Aug 29, 1995International Business Machines CorporationSystem for advising a surgeon
US5630431 *Oct 11, 1994May 20, 1997International Business Machines CorporationSystem and method for augmentation of surgery
US5695500 *Apr 6, 1994Dec 9, 1997International Business Machines CorporationSystem for manipulating movement of a surgical instrument with computer controlled brake
US5950629 *Apr 28, 1994Sep 14, 1999International Business Machines CorporationSystem for assisting a surgeon during surgery
US6231526Dec 8, 1999May 15, 2001International Business Machines CorporationSystem and method for augmentation of surgery
US6267769Apr 9, 1998Jul 31, 2001Regents Of The Universitiy Of MinnesotaTrajectory guide method and apparatus for use in magnetic resonance and computerized tomographic scanners
US6500210Dec 10, 1996Dec 31, 2002Seattle Systems, Inc.System and method for providing a sense of feel in a prosthetic or sensory impaired limb
US6547782Aug 11, 2000Apr 15, 2003International Business Machines, Corp.System and method for augmentation of surgery
US6752812Nov 21, 2000Jun 22, 2004Regent Of The University Of MinnesotaRemote actuation of trajectory guide
US7235084Jun 20, 2002Jun 26, 2007Image-Guided Neurologics, Inc.Deep organ access device and method
US7366561Apr 4, 2001Apr 29, 2008Medtronic, Inc.Robotic trajectory guide
US7497863Dec 4, 2004Mar 3, 2009Medtronic, Inc.Instrument guiding stage apparatus and method for using same
US7527601Dec 29, 2005May 5, 2009Intrapartum Ventures, LlcCervimeter
US7559935Feb 20, 2003Jul 14, 2009Medtronic, Inc.Target depth locators for trajectory guide for introducing an instrument
US7636596Dec 20, 2002Dec 22, 2009Medtronic, Inc.Organ access device and method
US7637915Jul 20, 2004Dec 29, 2009Medtronic, Inc.Trajectory guide with instrument immobilizer
US7654970Jan 16, 2008Feb 2, 2010Intrapartum, LlcCervical dilation measurement apparatus
US7658879May 4, 2006Feb 9, 2010Medtronic, Inc.Trajectory guide with angled or patterned guide lumens or height adjustment
US7699854May 4, 2006Apr 20, 2010Medtronic, Inc.Trajectory guide with angled or patterned guide lumens or height adjustment
US7704260Dec 6, 2004Apr 27, 2010Medtronic, Inc.Low profile instrument immobilizer
US7713216Apr 10, 2006May 11, 2010Intrapartum, LlcMethod for cervical dilation and/or measurement
US7744606Dec 4, 2004Jun 29, 2010Medtronic, Inc.Multi-lumen instrument guide
US7749176Apr 2, 2008Jul 6, 2010Intrapartum, LlcCervical dilation measurement apparatus
US7803163Oct 28, 2005Sep 28, 2010Medtronic, Inc.Multiple instrument retaining assembly and methods therefor
US7811239Apr 11, 2006Oct 12, 2010Intrapartum, LlcCervical dilation measurement apparatus
US7815651Jun 25, 2007Oct 19, 2010Medtronic, Inc.Device for immobilizing a primary instrument and method therefor
US7828809Jun 26, 2007Nov 9, 2010Medtronic, Inc.Device for immobilizing a primary instrument and method therefor
US7833231Jun 25, 2007Nov 16, 2010Medtronic, Inc.Device for immobilizing a primary instrument and method therefor
US7857820Jun 26, 2007Dec 28, 2010Medtronic, Inc.Sheath assembly for an access device and method therefor
US7867242Jan 7, 2009Jan 11, 2011Medtronic, Inc.Instrument for guiding stage apparatus and method for using same
US7896889Feb 20, 2003Mar 1, 2011Medtronic, Inc.Trajectory guide with angled or patterned lumens or height adjustment
US7981120Apr 23, 2007Jul 19, 2011University Of South FloridaTrajectory guide with angled or patterned guide lumens or height adjustment
US8083753Oct 16, 2007Dec 27, 2011Medtronic, Inc.Robotic trajectory guide
US8116850Nov 9, 2009Feb 14, 2012Medtronic, Inc.Organ access device and method
US8192445Nov 17, 2009Jun 5, 2012Medtronic, Inc.Trajectory guide with instrument immobilizer
DE4313843A1 *Apr 27, 1993Nov 24, 1994Stm Medtech StarnbergVorrichtung zur endoskopischen Exploration des Körpers
WO1998009565A1 *Sep 5, 1997Mar 12, 1998Lee A BlumenfeldMethod and apparatus for monitoring cervical diameter
Classifications
U.S. Classification600/588, 606/119
International ClassificationA61B5/03, A61B5/107
Cooperative ClassificationA61B5/435, A61B5/1076
European ClassificationA61B5/107J, A61B5/43F6A