|Número de publicación||USRE28990 E|
|Tipo de publicación||Concesión|
|Número de solicitud||US 05/547,716|
|Fecha de publicación||5 Oct 1976|
|Fecha de presentación||6 Feb 1975|
|Fecha de prioridad||4 Dic 1972|
|Número de publicación||05547716, 547716, US RE28990 E, US RE28990E, US-E-RE28990, USRE28990 E, USRE28990E|
|Inventores||Edward H. Hon, Robert W. Hon|
|Cesionario original||Corometrics Medical Systems, Inc.|
|Exportar cita||BiBTeX, EndNote, RefMan|
|Citas de patentes (24), Otras citas (15), Citada por (36), Clasificaciones (15)|
|Enlaces externos: USPTO, Cesión de USPTO, Espacenet|
This applicaton is a continuaton-in-part of U.S. Pat. application Ser. No. 108,034, filed Jan. 20, 1971.Iadd., now abandoned.Iaddend..
The present invention relates to an improved bipolar electrode structure adapted to be inserted through the vagina and cervix of a woman in labor, into contact with the fetus. The electrode structure is designed to be operatively connected to an amplifier and a cardiotachometer for recording the fetal electrocardiogram and heart rate during labor and delivery.
It has long been recognized that monitoring fetal heartbeat is a most important procedure during the conduct of labor. Various types of methods and apparatuses for performing this monitoring function have been designed in recent years. The most successful and practical techniques are those employing electrodes which are attached to the fetus.
One such technique is described in Volume 35, No. 1, of Obstetrics and Gynecology, January 1970 issue, pages 111-113. The technique there described utilizes a vaginal endoscope and specially designed forceps to apply a silver electrode to the fetal scalp.
A second type of electrode structure for recording fetal heartbeat is described in Volume 16, No. 5 of Obstetrics and Gynecology, November 1960 edition, pages 567-570, The electrode structure there described is a unipolar structure comprising a spring steel clip adapted to be closed by a sliding plastic sleeve to engage the fetal scalp or buttocks.
The foregoing electrode structures give rise to several problems which the structure of the present invention is designed to overcome. Both the "forceps-endoscope" and the "sliding sleeve-clip" types of electrodes cannot be applied until the mother's cervix has dilated to about 2.0 cm, and thus cannot ordinarily be applied during the very early stages of labor.
Another disadvantage associated with the foregoing types of electrodes is that both include clips which must be squeezed onto the fetal epidermis. These clips are extremely thin and brittle and are often cracked or damaged by mechanical stresses during application. Such cracks create electrical "noise" in the electrocardiogram system during the fetal heartbeat monitoring operation, and thus interfere with such monitoring studies.
The foregoing types of electrodes are also relatively difficult to apply and remove. The "forceps-endoscope" system reqires a specially designed lighting apparatus which must be used to insure proper application of the electrode.
In view of the foregoing, it is an object of the present invention to provide a vaginal electrode structure which overcomes the foregoing problems associated with the prior art electrode structures.
A further object of the present invention is to provide an improved, durable, vaginal electrode structure which can be quickly and effectively applied to the fetus during a relatively early stage of labor, and which can be quickly and easily removed.
FIG. 1 is a sectional side elevational view of the forward portion of a first preferred embodiment of the electrode structure of the present invention, with the various parts thereof positioned as they would be prior to use.
FIG. 2 is a perspective view of the holder member, first electrode, retaining coil and the forward end of the driving tube of the electrode structure shown in FIG. 1.
FIG. 3 is a sectional side elevational view of the rear portion of the electrode structure shown in FIGS. 1 and 2.
FIG. 4 is a sectional side elevational view showing the electrode structure of FIGS. 1-3 with a modified form of the second electrode.
FIGS. 5, 6 and 7 are diagrammatic views illustrating the manner in which the improved electrode structure of the present invention is applied to a fetus.
FIG. 8 is a perspective view of a second preferred embodiment of an electrode structure constructed according to the teachings of the present invention, wherein the retaining coil serves as the first electrode and wherein the first and second electrodes are mounted on the same holder.
FIG. 9 is a sectional side elevational view of the electrode structure shown in FIG. 8 with the various parts thereof positioned as they would be prior to use.
FIG. 10 is a side elevational view, partly in section, showing the electrode unit rotated 90 degrees from the position illustrated in FIG. 9.
Referring now to the drawings, the electrode structure 10 illustrated in FIGS. 1, 2 and 3 comprises a guide tube 12 having an open forward end through which a holding member 14 is movable, and an open rear end through which electrode wires 16, 18 extend. The guide tube 12 is curved .Iadd.and form-sustaining .Iaddend.(see FIGS. 5-7) to facilitate insertion of the tube through the vagina and cervix of a woman in labor.
One of the wires 16 extends through the holding member 14 and is electrically connected to a pointed electrode 20 which is preferably made of silver-silver chloride. The desirability of using a silver-silver chloride electrode is discussed in some detail in Volume 30, No. 2 of Obstetrics & Gynecology, August 1967 issue, pages 281-286. The electrode 20 is preferably crimped on the forward end of wire 16, as at 22 (FIG. 1) and soldered thereto to insure a good electrical connection.
An insulating sleeve 24 covers the juncture of the first wire 16 and the first electrode 20. Epoxy adhesive 26 fills and seals the annular space between the insulation 17 of wire 16 and the interior wall of the holder 14, behind the sleeve 24. The epoxy 26 also covers and seals the rear end of the holder 14.
Epoxy adhesive is also provided in the annular space 28 between the electrode 20 and the interior wall of tube 24, in the annular space 30 between the wire 16 and the interior wall of the tube 24, in the annular space between the wire insulation 17 and the interior wall of tube 24, and in the annular space 36 between the exterior wall of tube 24 and the interior wall of the holder 14. The epoxy adhesive at these locations insures a good seal from the forward end of the holder 14.
The forward end 40 of the holder 14 has a retaining coil 42 mounted thereon by means of a suitable adhesive 44 (e.g., epoxy). The retaining coil 42 (which may be plastic, metal or any other suitable material) is provided with a pointed forward end 46 to pierce the fetal epidermis. When the holding member 14 and the retaining coil 42 are rotated the retaining coil will "screw" into the fetus and bring the first electrode 20 into engagement with the fetal epidermis with the pointed tip 47 piercing the epidermis. The forward end 40 of the holder 14 acts as a "stopper" which limits the distance which the tip 47 of the first electrode 20 can travel into the fetus. The distance between the pointed end 46 of the retaining coil 42 and the forward end 40 of the holder member 14 is relatively small (e.g., about 1/16 of an inch).
As best shown in FIG. 2, the rear portion 49 of the holder member 14 is provided with a plurality of radially outwardly extending, circumferentialy spaced wings of fins 50,50,50,50, which are adapted to be releasably engaged by circumferentially spaced slots 52,52,52,52, in the forward end 53 of a flexible driving tube 54. .Iadd.The guide tube 12 is more rigid than the flexible driving tube 54 so that the guide tube will maintain its curved configuration when the flexible driving tube is rotated within it. .Iaddend.
The flexible driving tube 54 (preferably made of plastic) extends through the curved guide tube 12 for rotating the holder 14 and the retaining coil 42. As noted above, rotation of the holder 14 by the flexible driving tube 54 is accomplished via the slots 52 in the forward end 53 of the driving tube and the fins 50 on the holder. It should be noted that the driving connection between the fins 50 and the slots 52 is relatively "loose" so that the driving tube 54 will "slip" around the holder fins 50 when the holder meets with a relatively slight amount of resistance to rotation. Thus, when the holder 14 meets with resistance to rotation (e.g., when the first electrode 20 has pierced the fetal epidermis and the forward end of the holder has come into contact with the fetus), continued rotation of the driving tube 54 will not drive the retaining coil or first electrode further into the fetus. This "loose driving connection" may be accomplished by making the fins 54 or the driving tube segments 56 between the slots 52 "soft" or pliable enough so that they will bend and "slip" relative to one another when the holder 14 resists rotation.
Referring to FIG. 1, it will be seen that the forward end of the second conductor 18 terminates within the guide tube 12 substantially behind the holder 14. A silver-silver chloride electrode coil 60 is crimped (as at 62, FIG. 1) and soldered onto the forward end of the second conductor 18. The coil .[.20.]. .Iadd.60 .Iaddend.is the second electrode in the system and also functions to hold the conductors 16, 18 adjacent to one another.
A plastic insulating sleeve 64 is provided around the juncture of the electrode coil 60 and the second conductor 18 to eliminate or minimize any electrical noise which otherwise might be created if the juncture of the conductor 18 and the electrode coil 60 were exposed to vaginal fluids when the system is in use.
Epoxy adhesive is preferably provided between the interior wall of the insulating sleeve 64 and the rear end of the coil electrode 60 to seal the forward end of the insulating sleeve. Epoxy adhesive is also preferably provided between the conductor 18 and the interior wall of the insulating sleeve 64 (as at 66, FIG. 1), and between the interior wall of the insulating sleeve 64 and the insulation cover 19 on the second conductor 18 to seal these junctures.
In FIG. 4, an alternative structure for the second electrode is shown. In the FIG. 4 embodiment the second electrode 160 is in the form of a sleeve which is crimped and soldered onto the forward end of the second conductor 18 and an insulating sleeve 164 encloses both of the conductors 16, 18. Epoxy adhesive is preferably provided in the FIG. 4 structure to seal the juncture between the electrode sleeve 160 and the conductor 18 from vaginal fluids.
As best shown in FIG. 1, the electrode structure 10 of the present invention is packaged so that the retaining coil 42 and the first electrode 20 are well behind the forward end of the guide tube 12, thereby protecting the retaining coil and electrode from damage prior to use.
As best shown in FIG. 5, the rear ends of the wires 16, 18 are folded back and inserted between the rear end of the curved guide tube 12 and the rear portion of the flexible driving tube 54. A wedge 80 (FIGS. 5 and 7) may be inserted in the rear end of the driving tube 54 to .[.prevent relative sliding movement between the flexible driving tube and the wires 16, 18..]. .Iadd.wedge the wires 16 and 18 against the interior surface of the driving tube 54. Since wire 16 is secured to the holder 14, if the wires are pulled, the fins 50 are urged toward slots 52 of the driving tube. Accordingly, if the wires 16 and 18 are held with the fins 50 engaging slots 52 of the driving tube, the wires then aid in locking the holder and driving tube together during insertion of the electrode. .Iaddend.
The method of using the electrode structure 10 of the present invention is illustrated diagrammatically in FIGS. 5, 6 and 7.
With the first and second electrodes, 20 and 60, disposed within the guide tube 12, the doctor inserts the forward end of the curved guide tube through the mother's vagina 82 and cervix 84 until the forward end of the guide tube makes contact with the fetal head 86 (or other portion of the fetus), as shown in FIG. 5. The doctor then removes the folded-back ends of the wires 16, 18 from between the rear ends of the guide tube 12 and the driving tube 54 to permit relative sliding movement between these tubes. While holding the forward end of the guide tube 12 stationary, the doctor then pushes the rear end of the flexible driving tube 54 forwardly until the retaining coil 42 makes contact with the fetal epidermis (FIG. 6). An indicator mark 88 (FIGS. 5-7) may be provided on the driving tube 54 to visually warn the doctor when the retaining coil 42 has passed beyond the forward end of the guide tube 12.
When the doctor feels or sees that the retaining coil 42 has contacted the fetal epidermis 86, he rotates the flexible driving tube 54 (e.g., about one full turn) while maintaining the forward end of the guide tube 12 against the fetal head. This will screw the retaining coil 42 into the fetal epidermis and drive the pointed end of the first electrode 20 into the epidermis (see FIG. 6). It will be appreciated that the flexible construction of the driving tube 54 permits it to slide and rotate in the curved guide tube 12.
The wedge 80 is then removed from the rear end of the driving tube 54 to .[.permit relative sliding movement between the wires 16, 18 and.]. .Iadd.release wires 16 and 18 with respect to driving tube 54 and thereby permit disengagement of the interlocking fins 50 and slots 52 by withdrawal of .Iaddend.the driving tube. The doctor then removes his fingers from the mother's vagina 82, grasps the outer ends of the driving tube and the guide tube, and slides these tubes (as a unit) off of the wires 16, 18 leaving only the electrodes 20 and 60, and the very thin wires 16, 18 within the mother.
The outer ends of the wires 16, 18 are then connected to suitable apparatus (not shown) for monitoring fetal heartbeat.
FIGS. 8-10 illustrate a second preferred embodiment of the electrode structure of the present invention wherein the first electrode serves as the retaining coil and the second electrode is mounted on the holder member and serves as the fin means which cooperates with the slots in the forward end of the flexible driving tube to provide the driving connection between the holder and the driving tube.
Referring to FIG. 9, the electrode structure 210 comprises a curved .Iadd., form-sustaining .Iaddend.guide tube 212 having an open forward end through which a holder member 214 is adapted to pass. The holder member 214 has a spiral electrode 220 mounted in its forward end and a generally flat electrode 222 mounted in its rear end. .Iadd.
As shown in FIG. 9, the diameter of the cylindrical holder member 214 approximates the inner diameter of guide tube 212. Consequently, the holder member prevents lateral movement of the electrode coil 220 (relative to the guide tube) while the coil is being attached to the fetus. Moreover, the length of the holder member 214 is such that when the spiral electrode 220 extends just beyond the end of the guide tube 212 (for attachment to the fetus), the cylindrical holder member within the guide tube prevents skewing of the coil. These features help to reduce the possibility of injury to the fetus when the electrode is being applied. .Iaddend.
A first electrode wire 216 extends through the rear end of the holder member 214 and is electrically connected to the rear end of spiral electrode 220. A second electrode wire 218 also extends through the rear end of holder member 214 and is electrically connected to the forward end of the second electrode 222.
Both electrodes, 220 and 222, are preferably constructed of stainless steel and are soldered to their respective electrode wires, 216 and 218. The holder member 214 is made of an insulative material, such as plastic, and electrically isolates the electrodes 220 and 222 from one another.
A flexible driving tube 254 is slidably and rotatably disposed in the curved guide tube 212 for rotating the holder 214 to screw the spiral electrode 220 into a fetal epidermis. As best shown in FIG. 8, the forward end of the driving tube 254 is provided with a pair of slots 252, 252 which are adapted to receive the rearwardly extending portion of the plate electrode 222. When the slots 252, 252 on the forward end of the holder 214 engage the plate electrode 222 the holder 214 and the spiral electrode 220 may be rotated by rotating the flexible driving tube 254.
The electrode wires, 216 and 218, extend rearwardly through the rear portion (not shown) of the driving tube 254 and the rear portion (not shown) of the guide tube 212 for connection to a suitable apparatus (not shown) for monitoring fetal heartbeat.
The electrode structure 210 is used in the same manner as described above and illustrated in FIGS. 5-7 in connection with the structure of FIGS. 1-7. In use, with the spiral electrode 220, holder 214 and plate electrode 222 disposed within the curved guide tube 212, behind the forward end thereof, the doctor inserts the forward end of the guide tube 212 through the woman's vagina and cervix until the forward end of the guide tube makes contact with the fetal head (or other portion of the fetus) in the same manner as described above in connection with the electrode structure 10 illustrated in FIGS. 1-7. The doctor then holds the forward end of the guide tube 212 stationary and pushes the rear end of the flexible driving tube 254 forwardly until the spiral electrode 220 makes contact with the fetal epidermis.
When the doctor feels or sees that the spiral electrode 220 has contacted the fetal epidermis, he rotates the flexible driving tube 254 while maintaining the guide tube 212 against the fetal head to screw the spiral electrode 220 into the fetal epidermis.
It is intended that the present invention be limited only by the scope of the appended claims.
|Patente citada||Fecha de presentación||Fecha de publicación||Solicitante||Título|
|US2102270 *||29 Nov 1935||14 Dic 1937||Mortimer N Hyams||Electrosurgical device|
|US2839049 *||25 Mar 1954||17 Jun 1958||Maclean Kenneth S||Abrasive cytologic brush|
|US2890266 *||1 Mar 1955||9 Jun 1959||Minnesota Mining & Mfg||Wire-connector|
|US3087486 *||5 Mar 1959||30 Abr 1963||Cenco Instr Corp||Cardiac electrode means|
|US3120227 *||8 Jul 1960||4 Feb 1964||Robert J Braunlin||Method for obtaining a fetal electrocardiogram|
|US3216424 *||5 Feb 1962||9 Nov 1965||Chardack William M||Electrode and lead|
|US3222755 *||2 Ago 1961||14 Dic 1965||Grass Albert M||Method of assembling an electrode|
|US3253595 *||7 Ago 1963||31 May 1966||Cordis Corp||Cardiac pacer electrode system|
|US3326207 *||10 Jul 1964||20 Jun 1967||James J Egan||Electrocardiac instrument for testing unborn infants|
|US3348548 *||26 Abr 1965||24 Oct 1967||Chardack William M||Implantable electrode with stiffening stylet|
|US3410269 *||27 Dic 1965||12 Nov 1968||Gambrell James B||Obstetrical instrument for puncturing the amniotic membranes|
|US3416534 *||11 Abr 1966||17 Dic 1968||Gen Electric||Body organ electrode|
|US3420223 *||31 Dic 1964||7 Ene 1969||Nasa||Electrode for biological recording|
|US3472234 *||15 Ago 1967||14 Oct 1969||Gen Electric||Body organ electrode|
|US3474791 *||24 Mar 1966||28 Oct 1969||Brunswick Corp||Multiple conductor electrode|
|US3494364 *||9 Nov 1967||10 Feb 1970||Weck & Co Inc Edward||Handle component for electro-surgical instrument|
|US3533403 *||10 May 1967||13 Oct 1970||Woodson Riley D||Combination heart catheter and electrode|
|US3580242 *||1 Abr 1968||25 May 1971||George E La Croix||Fetal scalp electrode unit|
|US3737579 *||19 Abr 1971||5 Jun 1973||Medtronic Inc||Body tissue electrode and device for screwing the electrode into body tissue|
|US3750650 *||13 Dic 1971||7 Ago 1973||Hewlett Packard Gmbh||Double spiral electrode for intra-cavity attachment|
|US3800784 *||11 Jul 1972||2 Abr 1974||Medicor Muevek||Medical instrument for examining a fetus during delivery|
|US3835864 *||21 Sep 1970||17 Sep 1974||Rasor Ass Inc||Intra-cardiac stimulator|
|US3844292 *||9 Jun 1972||29 Oct 1974||Medtronic Inc||Intravascular lead assembly|
|DE2004422A1 *||31 Ene 1970||5 Ago 1971||Siemens Ag||Injector for egg electrodes|
|1||*||Caldeyro-Barcia et al., - Digest - 1961, International Conference on Medical Electronics, p. 1.|
|2||*||Hon et al., "American Journal of Obstetrics & Gynecology", vol. 79, No. 5, May 1960, pp. 1012-1023.|
|3||*||Hon et al., "Obstetrics & Gynecology", vol. 40, No. 3, Sept. 1972, pp. 362-365.|
|4||*||Hon, "American Journal of Obstetrics & Gynecology", vol. 86, No. 6, July 15, 1963, pp. 772-784.|
|5||*||Hon, "Connecticut Medicine", vol. XXIV, No. 5, May 1960, pp. 289-293.|
|6||*||Hon, "Obstetrics & Gynecology", vol. 30, No. 2, Aug. 1967, pp. 281-286.|
|7||*||Hon, "The Yale Journal of Biology & Medicine", vol. 32, No. 5, April 1960, pp. 397-399.|
|8||*||Hon, "The Yale Journal of Biology & Medicine", vol. 39, No. 1, Aug. 1966, pp. 54-58.|
|9||*||Hunter, Jr. et al., "Obstetrics & Gynecology", vol. 16, No. 5, Nov. 1960, pp. 567-570.|
|10||*||Japanese Article - No translation or citation given.|
|11||*||Junge, "Geburtshilfe und Frauenheilkeit," vol. 29, pp. 129-133, 1969.|
|12||*||Kuahama et al., "Japanese Journal of Medical Electronics & Biomedical Journal," vol. 5, No. 3, 7/67, pp. 199-201.|
|13||*||La Croix, "Michigan Medicine", Aug. 1968, pp. 976-979.|
|14||*||Ruttgers et al., article - no citation given, pp. 654-660.|
|15||*||Smyth, The Lancet, June 6, 1933, pp. 1124-1126.|
|Patente citante||Fecha de presentación||Fecha de publicación||Solicitante||Título|
|US4974593 *||24 Nov 1989||4 Dic 1990||Ng Raymond C||Holder apparatus for transducer applicable to human body|
|US5012811 *||20 Dic 1988||7 May 1991||American Home Products Corporation||Fetal electrode product with protective cap|
|US5135006 *||24 Jul 1990||4 Ago 1992||Susan Bellinson||Method and apparatus for monitoring descent of fetus|
|US5150709 *||11 Feb 1991||29 Sep 1992||Neward Theodore C||Spiral electrode with contact retainer|
|US5168876 *||26 Feb 1991||8 Dic 1992||American Home Products Corporation||Connector device for use in monitoring fetal heart rate|
|US5199432 *||30 Oct 1990||6 Abr 1993||American Home Products Corporation||Fetal electrode product for use in monitoring fetal heart rate|
|US5205288 *||7 Oct 1991||27 Abr 1993||American Home Products Corporation||Fetal electrode product with female socket connector and connector device with male plug connector each for use in monitoring fetal heart rate|
|US5222498 *||3 Ago 1992||29 Jun 1993||Neward Theodore C||Spiral electrode with contact retainer|
|US5257627 *||14 Nov 1991||2 Nov 1993||Telmed, Inc.||Portable non-invasive testing apparatus|
|US5265613 *||3 Abr 1992||30 Nov 1993||Telmed, Inc.||Portable non-invasive testing apparatus with logarithmic amplification|
|US5373843 *||24 Dic 1992||20 Dic 1994||Corometrics Medical Systems, Inc.||Connector device for use in monitoring fetal heart rate|
|US5377677 *||23 Sep 1993||3 Ene 1995||Graphic Controls Corporation||Packaging system for a fetal electrode|
|US5388579 *||23 Sep 1993||14 Feb 1995||Graphic Controls Corporation||Fetal electrode product with channeled drive mechanism and improved torque characteristics|
|US5411024 *||15 Dic 1993||2 May 1995||Corometrics Medical Systems, Inc.||Fetal pulse oximetry sensor|
|US5419322 *||22 Jul 1993||30 May 1995||Joseph; Barry M.||Internal apparatus for continuous electrical and oximetric intrapartum monitoring of the fetus|
|US5423314 *||2 Ago 1993||13 Jun 1995||Hewlett Packard Company||Introduction apparatus for a fetal scalp electrode|
|US5474065 *||4 Abr 1994||12 Dic 1995||Graphic Controls Corporation||Non-invasive fetal probe|
|US5489294 *||1 Feb 1994||6 Feb 1996||Medtronic, Inc.||Steroid eluting stitch-in chronic cardiac lead|
|US5551424 *||7 Jun 1995||3 Sep 1996||Phox Medical Optics, Inc.||Fetal probe apparatus|
|US5615674 *||22 Mar 1995||1 Abr 1997||Hewlett-Packard Company||Clamping contact connection|
|US5632274 *||6 Dic 1994||27 May 1997||Corometrics Medical Systems||Connection arrangement for monitoring fetal heart rate|
|US5665477 *||7 Jun 1995||9 Sep 1997||Graphic Controls Corporation||Hydrogel adhesive for attaching medical device to patient|
|US5671736 *||17 Oct 1995||30 Sep 1997||Graphic Controls Corporation||Fetal electrode product with easy-to-handle connector|
|US5680859 *||11 Oct 1995||28 Oct 1997||Graphic Controls Corporation||Integrated introducer and drive rod positioning system for a fetal spiral electrode|
|US5833622 *||31 Oct 1996||10 Nov 1998||Graphic Controls Corporation||Non-invasive fetal probe having improved mechanical and electrical properties|
|US6356778||8 Mar 2000||12 Mar 2002||Ge Medical Systems Information Technologies, Inc.||Connector assembly for fetal scalp electrode|
|US6363272||4 Oct 2000||26 Mar 2002||Ge Medical Systems Information Technologies, Inc.||Connector for fetal probe|
|US6421549||14 Jul 2000||16 Jul 2002||Providence Health System-Oregon||Adaptive calibration pulsed oximetry method and device|
|US6760609||15 Jul 2002||6 Jul 2004||Providence Health System - Oregon||Adaptive calibration pulsed oximetry method and device|
|US7336985||30 Sep 2004||26 Feb 2008||Clinical Innovations, Llc||Fetal heart rate electrode assembly, connector for same, cable assembly, system, and methods of use|
|US20050137486 *||30 Sep 2004||23 Jun 2005||Wallace Wm. D.||Fetal heart rate electrode assembly, connector for same, cable assembly, system, and methods of use|
|DE4228351C1 *||26 Ago 1992||7 Abr 1994||Hewlett Packard Gmbh||Foetal scalp electrode insertion appliance - has bayonet fixing for electrode head to insertion tube|
|EP0004510A1 *||20 Mar 1979||3 Oct 1979||ANVAR Agence Nationale de Valorisation de la Recherche||Measuring device for physiological signals to be placed on or inside a part of the body|
|EP0092982A2 *||21 Abr 1983||2 Nov 1983||American Home Products Corporation||Detection of fetal death|
|EP0113253A2 *||29 Dic 1983||11 Jul 1984||Rocket of London Limited||Medical instrument|
|WO1989009024A1 *||31 Mar 1989||5 Oct 1989||Susan A Bellinson||Method and apparatus for fetal descent monitoring|
|Clasificación de EE.UU.||600/376|
|Clasificación internacional||A61B5/0444, A61B5/0448, A61B5/0408, A61N1/05|
|Clasificación cooperativa||A61B5/0408, A61B5/0448, A61B5/4362, A61B5/0444, A61N1/05|
|Clasificación europea||A61B5/43F6E, A61B5/0408, A61B5/0448, A61B5/0444, A61N1/05|