Patent Publication Number: US-10328254-B2

Title: Uterine electrical stimulation system and method

Description:
RELATED APPLICATIONS 
     This application is a divisional of U.S. patent application 14/609,093, filed Jan. 29, 2015, which is a divisional of U.S. patent application 13/881,812, filed Apr. 26, 2013, which represents the national stage entry of PCT International Application No. PCT/US2011/057856 filed on Oct. 26, 2011, and claims priority under 35 U.S.C. § 119 to U.S. Provisional Patent Application No. 61/407,397 filed on Oct. 27, 2010, all of which are incorporated herein by reference. 
    
    
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH 
     N/A. 
     BACKGROUND OF THE INVENTION 
     The present application is directed to systems and methods for applying stimulating current to a patient for treating insufficient uterine contractions. 
     Postpartum hemorrhage, which is a significant source of maternal morbidity and mortality in modern obstetrics, occurs in up to 18 percent of births (1,2). Even with appropriate management, approximately 3-4 percent of vaginal deliveries result in severe postpartum hemorrhage in the United States and in other developed nations (3), which can result in occult myocardial ischemia, dilutional coagulopathy, and death (4). While sudden death can occur from rapid and uncontrolled postpartum hemorrhage because of brisk blood loss, many deaths are the result of ineffective management of continuous low-level bleeding (5). In less-developed countries and in rural areas of the United States, maternal hemorrhage is a greater issue. For example, in Zimbabwe, hemorrhage is responsible for 25 percent of maternal deaths. Approximately 125,000 women per year die worldwide due to postpartum hemorrhage (6). 
     Uterine atony causes more than 90 percent of cases of postpartum hemorrhage (5). Uterine atony is a loss of tone in the uterine musculature postpartum, resulting in the failure of uterine muscles to contract tonically and stop postpartum bleeding. This may be related to the inability of myometrial cells in some patients to act properly as pacemakers for tonic (or phasic) contractions after delivery (7), or may be related to changes in threshold or resting potentials brought on by the delivery process or by administration of medications (8). 
     Normally, contraction of the uterine muscle compresses the vessels and reduces blood flow after delivery. This increases coagulation, which prevents bleeding. However, lack of uterine muscle contractions can cause an acute postpartum hemorrhage. Many factors can contribute to the loss of uterine muscle tone, including overdistention of the uterus, multiple gestations, polyhydramnios, fetal macrosomia, prolonged labor, oxytocin augmentation of labor, grand multiparity (having given birth 5 or more times), precipitous labor (labor lasting less than 3 hours), magnesium sulfate treatment of preeclampsia, chorioamnionitis, halogenated anesthetics, and uterine leiomyomata (9). 
     Current treatments for preventing blood loss during uterine atony and/or uterine rupture include radical procedures such as surgery, manual massage, which is often minimally effective, and drugs, such as oxytocin, prostaglandins, and ergot alkyloids. Oxytocin and other drug treatment is a common global application, however such treatment is often not well controlled and can have dangerous side effects for both the mother and the fetus. 
     SUMMARY OF THE INVENTION 
     The present invention provides a system for treating insufficient uterine contractions in a patient after labor and delivery. The system includes one or more stimulation electrodes coupled to or positioned along one of a uterus, a cervix, a vaginal wall, and an abdominal wall of a patient to apply stimulating current to the patient in order to treat insufficient uterine contractions, and more specifically, for the patient to produce tonic uterine contractions. The stimulation electrodes can be part of a balloon electrode array device, a ring electrode array device, an electrode probe device, and/or a mesh electrode array device. The system can also include electronics for generating and providing the stimulating current to the stimulation electrodes. Some aspects of the invention also provide a connector and cable device for coupling the stimulation electrodes to the electronics. 
     In one aspect of the invention, a balloon electrode array device includes at least one balloon, an access tube extending into the at least one balloon, a plurality of lead wires routed through the access tube and into an inside portion of the balloon, and a plurality of electrodes. Each one of the plurality of electrodes is coupled to one of the plurality of lead wires, and the plurality of electrodes extend from the inside portion of the balloon to an outer surface of the balloon. 
     In another aspect of the invention, a mesh electrode array device includes a non-conductive mesh material with a plurality of segments and nodes of intersection of the plurality of segments. The mesh electrode array device also includes a plurality of electrodes, where each one of the plurality of electrodes is coupled to one of the nodes of intersection, and a plurality of lead wires. Each one of the plurality of lead wires is coupled to one of the plurality of electrodes. 
     Other aspects of the invention include an electrode probe device and a ring electrode array device. The electrode probe device includes a substantially cylindrical probe with a first end and an opposite second end, at least one electrode positioned adjacent to the first end, and at least one lead wire electrically coupled to the at least one electrode. The ring electrode array device includes a flexible ring, a plurality of electrodes affixed to an outer surface of the flexible ring, and a plurality of lead wires electrically coupled to the electrodes. 
     In yet another aspect of the invention, a connector device includes an electronics connector plug capable of being releasably coupled to a system that produces stimulating current and configured to receive the stimulating current from the system. The connector device also includes a lead wire connector plug capable of being releasably coupled to an electrode device and configured to deliver the stimulating current to the electrode device, and a flexible, electrically insulated cable electrically connecting the electronics connector plug and the lead wire connector plug. 
     The foregoing and other aspects and advantages of the invention will appear from the following description. In the description, reference is made to the accompanying drawings which form a part hereof, and in which there is shown by way of illustration a preferred embodiment of the invention. Such embodiment does not necessarily represent the full scope of the invention, however, and reference is made therefore to the claims and herein for interpreting the scope of the invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  illustrates different types of observable uterine contractile events. 
         FIG. 2  is a graph illustrating a measured electrical power of contracting uterine muscles at different action potential frequencies. 
         FIG. 3  is a graph illustrating forces exerted by contracting uterine muscles over time when stimulating current is applied at different pulse frequencies. 
         FIG. 4  is a schematic of an in vitro setup for stimulating uterine tissue and measuring resulting contractile activity. 
         FIG. 5  is a graph illustrating a contractile recording of rat uterine tissue when varying pulse frequency in applied stimulation current. 
         FIG. 6  is a graph illustrating a contractile recording of human uterine tissue, when varying pulse frequency in applied stimulation current. 
         FIG. 7  is a graph illustrating a contractile recording of human uterine tissue, when varying train duration in applied stimulation current. 
         FIG. 8  is another graph illustrating contractile recordings of human uterine tissue, including a control trace and a test trace, when varying train duration in applied stimulation current. 
         FIG. 9  is another graph illustrating contractile recordings of human uterine tissue, when varying pulse frequency outside conventional parameters in applied stimulation current, in accordance with the present invention. 
         FIG. 10  is a schematic view of a system for use with the present invention. 
         FIG. 11  is a front cross-sectional view of a uterus. 
         FIG. 12A  is a side cross-sectional view of a uterus normally contracting post-partum. 
         FIG. 12B  is a side cross-sectional view of a ruptured uterus, which is not contracting post-partum due to uterine atony. 
         FIG. 12C  is a side cross-sectional view of a ruptured uterus being stimulated by the system of  FIG. 10 . 
         FIG. 13  is a side view of a balloon electrode array device for use with the present invention. 
         FIG. 14A  is a front cross-sectional view of the balloon electrode array device of  FIG. 13  in an inflated state. 
         FIG. 14B  is a front cross-sectional view of the balloon electrode array device of  FIG. 13  in a deflated state. 
         FIG. 15A  is a side view of a ring electrode array device for use with the present invention. 
         FIG. 15B  is a front cross-sectional view of the ring electrode array device of  FIG. 15A . 
         FIG. 16A  is a side views of the ring electrode array device of  FIG. 15A , including applicators. 
         FIG. 16B  is a side view of the ring electrode array device of  FIG. 15A , including applicators. 
         FIG. 17A  is a perspective views of an electrode probe device for use with the present invention. 
         FIG. 17B  is a perspective views of an electrode probe device for use with the present invention. 
         FIG. 17C  are perspective views of an electrode probe device for use with the present invention. 
         FIG. 18A  is a mesh structures of a mesh electrode array device for use with the present invention. 
         FIG. 18B  is a mesh structures of a mesh electrode array device for use with the present invention. 
         FIG. 19  illustrates side views of electrodes for use with the present invention. 
         FIG. 20A  is a perspective views of a mesh electrode array device for use with the present invention. 
         FIG. 20B  is a perspective views of a mesh electrode array device for use with the present invention. 
         FIG. 20C  is a perspective views of a mesh electrode array device for use with the present invention. 
         FIG. 21A  is a perspective view of a connector and cable device for use with the present invention. 
         FIG. 21B  is a perspective view of another connector and cable device for use with the present invention. 
         FIG. 22A  is a front views of pin connector arrays of the connector and cable device of  FIGS. 21A and 21B . 
         FIG. 22B  is a front views of pin connector arrays of the connector and cable device of  FIGS. 21A and 21B . 
         FIG. 23A  is a schematic views of a connector pin of the pin connector arrays of  FIGS. 22A and 22B . 
         FIG. 23B  is a schematic views of a connector pin of the pin connector arrays of  FIGS. 22A and 22B . 
         FIG. 24A  is a perspective view of a male connector pin for use with the pin connector arrays of  FIGS. 22A and 22B . 
         FIG. 24B  is a perspective view of a female connector pin for use with the pin connector arrays of  FIGS. 22A and 22B . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Before any embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including,” “comprising,” or “having” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. Unless specified or limited otherwise, the terms “mounted,” “connected,” “supported,” and “coupled” and variations thereof are used broadly and encompass both direct and indirect mountings, connections, supports, and couplings. Further, “connected” and “coupled” are not restricted to physical or mechanical connections or couplings. Where appropriate, the terms “stimulation” and “stimulated” are understood to refer to electrical stimulation and electrically stimulated, respectively. 
     The following discussion is presented to enable a person skilled in the art to make and use embodiments of the invention. Various modifications to the illustrated embodiments will be readily apparent to those skilled in the art, and the generic principles herein can be applied to other embodiments and applications without departing from embodiments of the invention. Thus, embodiments of the invention are not intended to be limited to embodiments shown, but are to be accorded the widest scope consistent with the principles and features disclosed herein. The following detailed description is to be read with reference to the figures, in which like elements in different figures have like reference numerals. The figures, which are not necessarily to scale, depict selected embodiments and are not intended to limit the scope of embodiments of the invention. Skilled artisans will recognize the examples provided herein have many useful alternatives and fall within the scope of embodiments of the invention. 
     Some embodiments of the invention provide a system and method of treating uterine atony by administering electrical stimulation to the uterus. The electrical stimulation to the uterus can result in uterine muscle contractile activity, which can aid in decreasing and/or stopping uterine bleeding. 
     There are several different types of observable uterine contractile events. As shown in  FIG. 1 , some uterine contractile events can include spontaneous phasic contractions (spontaneous contractions which are short in duration and occur without outside stimulation), short stimulated phasic contractions (stimulated contractions which are shorter in duration and stop at or before the time stimulation is stopped), long stimulated phasic contractions (stimulated contractions which are longer in duration and stop immediately after the time stimulation is stopped), and tonic contractions (sustained contractions which persist long after stimulation is stopped). During labor and delivery, the human uterus exhibits spontaneous phasic contractions that produce associated electrical action potential frequencies in the range of 0.0 Hertz (Hz) to about 3.0 Hz. In addition, to a lesser degree, the human uterus also exhibits spontaneous phasic contractions during menstrual cycles in non-pregnant women. As shown in  FIG. 2 , electrical power output of human uterine spontaneous phasic contractions is mostly concentrated at less than 1.0 Hz. Very little electrical power is observed in higher frequencies than the above described range. 
     Current stimulation systems are used for stimulating the uterine tissue with similar frequencies as those seen naturally, using an external power source to induce contractions in laboring women who experience insufficient contractions to adequately deliver a baby. For example, U.S. Pat. No. 6,356,777, the entire contents of which is incorporated herein by reference, specifies the use of electrical stimulating frequencies in the 0.0 Hz to about 5.0 Hz range for controlling phasic contractions. The uterus responds favorably to such electrical stimulation signals by exhibiting stimulated phasic contractions, like those occurring naturally during labor and delivery, as shown in  FIG. 3 . 
       FIG. 3  illustrates uterine muscle activity over time when a stimulation current is applied. As shown in  FIG. 3 , uterine muscle action returns to baseline immediately after the current is switched off when using frequencies up to about 5 Hz. In some instances, the maximal contractile activity begins to fall well before the current is turned off, which is indicative of stimulated phasic contractile activity. The stimulated phasic contractile activity shown in  FIG. 3  can be considered short stimulated phasic contractions, as the stimulation duration is substantially small (e.g., less than about 3 minutes) and the stimulation frequency lies within the conventional uterine stimulation frequency range. In some embodiments, short stimulated phasic contractions can be specified as having a minimal duration time of about 30 seconds and a maximum duration time of about 3 minutes. Uterine muscle stimulation within these established ranges and the resulting phasic contractile activity are not thought to be useful for stopping uterine blood loss in the case of uterine rupture and postpartum hemorrhage. 
       FIG. 4  illustrates an in vitro setup  10  for stimulating uterine tissue and measuring resulting contractile activity. The setup includes one or more strips  12  (i.e., strips of uterine muscle tissue) outfitted with a plurality of stimulation electrodes  14  at each end (i.e., through suturing) isolated in a bath  16  of Krebs solution. Electrode lead wires  18  are Teflon-coated so as to act as insulation from the Krebs solution to prevent shorting of electrical current. The setup  10  also includes a source  20  for providing electrical stimulation with varying parameters. Tension force of the strips are recorded using a transducer (e.g., force gauge  21 ) and a computer obtains force data sensed by the transducer for analysis and display. The following paragraphs describe force data obtained from setups similar to that described with reference to  FIG. 4 , using tissue of pregnant patients in labor or after delivery. 
       FIG. 5  illustrates resulting force data from a test strip  12  of rat uterine tissue, when varying the stimulation current frequency (at 1 Hz, 2 Hz, 3 Hz, and 5 Hz), with stimulation voltage and train duration fixed. Each frequency tested produced a visible contractile response, resulting in short stimulated phasic contractions.  FIG. 6  illustrates resulting force data from a test strip  12  of human uterine tissue, with stimulation current frequency varied (at 1 Hz, 2 Hz, and 5 Hz), with stimulation voltage and train duration fixed. Each frequency tested produced a short stimulated phasic contraction.  FIG. 7  illustrates resulting force data from a test strip  12  of human uterine tissue, with stimulation current train duration varied (at 1 second, 2 seconds, 3 seconds, 5 seconds, and 10 seconds), with stimulation voltage and frequency fixed. No noticeable response was seen from 1-second and 2-second train durations. However, train durations of 3 seconds, 5 seconds, and 10 seconds produced short stimulated phasic contractions. The short stimulated phasic contractions shown in  FIGS. 5-7 , while useful for inducing or augmenting labor in women whose uterine function is insufficient for successful labor and delivery, are not useful for stopping blood loss during uterine atony and postpartum hemorrhage. 
       FIG. 8  illustrates resulting force data from test and control strips  12  of human myometrial tissue that were obtained from a term patient (39 weeks gestation) who demonstrated insufficient contractile activity during labor. Electrical stimulation at about 10 volts in pulses of about 2 Hz were applied to the test strip  12 . The pulses were run for a 5 minute duration (period  1 ), a 10 minute duration (period  2 ), and a 20 minute duration (period  3 ).  FIG. 8  shows spontaneous phasic contractile activity in the control strip  12  (top trace, no outside electrical stimulation provided), and spontaneous phasic contractile activity as well as stimulated phasic contractile activity in the test strip  12  (bottom trace, outside electrical stimulation provided by the source  20 ). The test strip  12  produced stimulated phasic contractile activity during period  1 , period  2 , and period  3  as a result of direct electrical stimulation of the test tissue. The duration of the stimulated phasic contractile activity was in direct proportion to the duration of the electrical stimulation current applied, and when the electrical stimulation current was turned off, the test strip force measurement returned fully to baseline, illustrating complete relaxation of the tissue. 
     The stimulated phasic contractile activity shown in  FIG. 8  can be considered long stimulated phasic contractions, as the stimulation duration is longer than about 3 minutes and the stimulation frequency lies within the conventional uterine stimulation frequency range. In some embodiments, long stimulated phasic contractions may be effective for reducing bleeding during postpartum hemorrhage and uterine atony, however, the amount of electrical energy required, and the length of time that the uterine tissue is exposed to such energy, may be too large to be of practical value in other embodiments. 
       FIG. 9  illustrates resulting force data from two test strips  12  of human uterine tissue, with electrical stimulation frequencies varied (at 6 Hz, 10 Hz, 20 Hz) and with electrical stimulation current pulse train duration varied (at 60 seconds, 120 seconds, 300 seconds, 1200 seconds). Spikes shown in  FIG. 9  indicate uterine muscle contractions. The spikes labeled “P” indicate initial preparatory contractions. The spikes labeled “S” indicate spontaneous uterine phasic contractions. The solid bars under the long spikes indicate the time periods during which electrical stimulation currents were applied to the uterine muscles. These time durations of electrical stimulation are indicated above the long spikes (in seconds) following the letter “E”. While frequencies greater than or equal to about 5.0 Hz lie outside of the established range of frequencies normally associated with uterine electrical activity, they are capable of producing a muscle response in the form of sustained uterine contractions. These contractions can be considered tonic contractions (a type not observed during labor and delivery or using electrical stimulation on the uterus within established frequencies). As shown in  FIG. 9 , these tonic contractions remain forceful well after the treatment has stopped (i.e., after the applied electrical current has been turned off). In some embodiments, these tonic contractions (i.e., forceful and sustained contractions) or tetanic contractions (i.e., tonic contractions which remain maximally, or near-maximally, forceful) can be very useful for stopping blood loss during uterine atony and uterine rupture. 
     Tonic contractile events are not possible to achieve using conventional electrical stimulation parameters (i.e., 0.0 Hz to about 5.0 Hz), which only seem capable of producing phasic contractions of the type observed during labor and delivery. Also, presently available drugs and systems, including oxytocin, are not capable of producing sustained, forceful contractions after treatment with them has completed. In some embodiments, only tonic contractions, achieved using frequencies at or above about 5.0 Hz, can be useful for contracting the uterus during critical bleeding in women with uterine atony and/or uterine rupture. These types of contractions can help reduce the bleeding to allow doctors enough time to stabilize the patient with other methods (e.g., to suture the uterus if needed without having to perform more radical surgery, like a hysterectomy), or can help stop the bleeding completely on their own. 
       FIG. 10  illustrates a system  22  according to one embodiment of the invention. The system  22  can stimulate uterine muscles into tonic contractions using frequencies greater than about 5.0 Hz. The system  22  can be used to stimulate muscles of the uterus in a way that does not affect other organs and can be accurately regulated and controlled, unlike oxytocin or other conventionally-used drugs. The system  22  can be used on a patient, such as a female post-partum, and can be controlled by a user, such as a physician or medical staff member. For example, the system  22  can input innocuous electrical pulses into the patient&#39;s uterus with sufficient effect to incite postpartum tonic or tetanic contractions in order to help treat uterine atony and postpartum hemorrhage. In some embodiments, the system  22  can include a control module  24 , a current source  26 , an isolation unit  28 , a constant maximum current unit  30 , a biphasic converter  32 , a set of lead wires  34 , and a set of electrodes  36 . 
     The control module  24  can contain computing capability, software, and memory. The control module  24  can be set using interface controls  33 , such as dials, switches and/or auxiliary inputs, to perform preprogrammed stimulation tasks, including commanding the current source  26  to output stimulation current of selected frequency, amplitude, pulse width, and train duration automatically for selected periods of time. The control module  24  can also be operated manually by the user, in which the user can determine and set one or more output stimulation currents of desired frequencies, amplitudes, pulse widths, and train durations as needed spontaneously (i.e., in real time or in near-real time). For example, the control module  24  can be operated automatically or manually to produce a stimulation current which can cause tonic or tetanic contractions of the patient&#39;s uterine muscle, and the user has the capability to adjust the stimulation current parameters (i.e., frequencies, amplitudes, pulse widths, and/or train durations) in real time or near-real time during observation of the patient&#39;s uterus. 
     In one embodiment, the control module  24  can automatically or manually operate multiple stimulation outputs of the current source  26  independently or in unison with varying or similar current frequencies, amplitudes, pulse widths, and train durations. As a result, the control module  24  can provide stimulation currents directly to the uterus or through various organs, such as the cervix, vaginal wall and/or abdominal wall separately, simultaneously, or sequentially, or can provide stimulation currents to various parts of the uterus separately, simultaneously, or sequentially. 
     In one embodiment, pre-recorded uterine electrical traces, obtained from normally contracting patients and saved digitally, can be stored in the control module  24  to be used, in turn as the electrical current trace patterns for commanding the current source  26  to output identical stimulation current to patients with abnormal uterine activity, such as patients with insufficient or absent contractile activity during postpartum hemorrhage. In addition, artificially generated current traces, saved digitally, with known frequencies, amplitudes, pulse widths, and train durations, can be stored in the control module  24  to be used as the electrical current trace patterns for commanding the current source  26  to output identical stimulation current to patients with abnormal uterine activity during postpartum hemorrhage. 
     In another embodiment, the control module  24  can automatically regulate and modify the electrical current output produced by the current source  26  based on input from electrical contractile activity of the patient&#39;s uterus, which can be transmitted to the control module  24  via pick-up wires, a signal conditioner, and/or after-conditioning wires (not shown). The control module  24  can regulate and modify the produced electrical current by changing the electrical stimulation pulse-width, current amplitude, pulse train duration, and/or the pulse frequency according to a pre-programmed algorithm. 
     In some embodiments, the control module  24  can include a display  37  (as shown in  FIG. 10 ), such as a video display, a digital display, light-emitting diode (LED) display, etc., to display the stimulation output currents produced for the user to read or assess. The control module  24  can be coupled to the current source  26  by wires, direct electrical coupling, or another suitable coupling. For example, in one embodiment, the control module  24  can communicate with the current source  26  via a wireless connection, such as Bluetooth®. 
     The current source  26  can generate the output stimulation current. In one embodiment, the electrical stimulation current settings can be adjusted manually at the current source  26  by the user using interface controls  35 , such as dials, switches or other devices. In another embodiment, the electrical stimulation settings can be controlled by the control module  24  (e.g., as preprogrammed settings or by the user using the interface controls  33 , as described above), and output to the current source  26 . As described above, in some embodiments, the current source  26  can output multiple electrical stimulation currents either directly to the uterus or indirectly to the uterus via the cervix, the vaginal wall and/or the abdominal wall separately, simultaneously, or sequentially, as commanded by the control module  24 , or the current source  26  can output multiple electrical stimulation currents to various locations of the uterus separately, simultaneously, or sequentially. 
     In some embodiments, there can be a constant two-way communication between the current source  26  and the control module  24 , so that the current source  26  can receive commands from the control module  24  and the control module  24  can receive actual output current values from the current source  26 . 
     In some embodiments, the current source  26  can be capable of generating an output current between about 0.01 milliamperes and about 100.00 milliamperes (with possible voltages between about 0.0001 volts and about 100 volts). Pulse widths of the current can be adjusted between about 0.1 millisecond and about 1000 milliseconds. Frequencies of the current can be adjusted from about 0.1 Hertz to about 30 Hz or greater, or about 100 Hz or greater. Pulse train durations can be adjusted from about 1 second to about 10,000 seconds. In addition, output currents can be sinusoidal so as to reduce tissue damage and maximize effect (10). In one embodiment, the current source  26  can produce a maximal “jolt” of uterine electrical stimulation energy equivalent to between about 1 Joule and about 120 Joules of electrical energy in a short duration between about 1 millisecond and about 1000 milliseconds. Further, the electrical stimulation current output from the current source  26  can be sensed, measured, or detected by either the current source  26  or the control module  24  and can be automatically shut off if current values are determined to be dangerous or outside prescribed, programmed, or set values. 
     The isolation unit  28  can prevent ground loop currents from affecting the patient. In one embodiment, isolation is accomplished through optical isolation. In other embodiments, induction or other methods of isolation can be used by the isolation unit  28 . 
     The constant maximum current unit  30  can allow the user to regulate the amount of maximum current that the patient&#39;s uterus receives. The constant maximum current unit  30  can prevent tissue damage due to extreme current fluctuations as tissue resistance varies (11), and can be set (either in a discrete or continuous fashion) to or between values well below human threshold for human feeling (e.g., about 0.01 milliamperes) and values uncomfortable for humans (e.g., about 100 milliamperes). In one example, the constant maximum stimulation current can be set at a value which maximizes current input without damaging tissue and with minimal discomfort to the patient (e.g., about 4 milliamperes). 
     The biphasic converter  32  can alternate the polarity of current pulses produced by the current source  26  after having moved through the isolation unit  28  and the constant maximum current unit  30  in order to further prevent adverse effects on the patient&#39;s tissues. The biphasic converter  32  can insure that the total energy delivered at the tissue site, as integrated over time, has a net value of zero. This can reduce the possibility of heating and subsequent damage to the patient&#39;s tissues ( 11 ,  12 ). 
     The lead wires  34  can transmit the output current from the biphasic converter  32  to the electrodes  36 . In one embodiment, the lead wires  34  can be those manufactured by Advantage Medical Cables or similar devices. In some embodiments, the system  22  can include between one and fifty lead wires  34 . For example, different lead wires  34  can carry different types or strengths of currents that incite, induce, or augment a tonic contraction at different times in different parts of the uterus, as preprogrammed or set by the user (e.g., to stimulate various parts of the patient&#39;s uterus separately, simultaneously, and/or sequentially). In some embodiments, the lead wires  34  can be insulated. 
       FIG. 11  illustrates a patient&#39;s uterus  38 , ovaries  40 , fallopian tubes  42 , a uterine body (or intrauterine cavity)  44 , a cervix  46 , a vagina  48 , a fundus  50  (i.e., top portion) of the uterus, and a distal portion  52  of the uterus. The electrodes  36  can be attached to or near the uterus  38  in a specific orientation and at specific locations that will have the best effect upon uterine contractility for the patient, as determined by the user. In one example, the electrodes  36  can be placed upon the vaginal wall  48  and/or the cervix  46 . In another example, the electrodes  36  can be placed at locations across the fundal portion  50  and distal portion  52  of the uterus  38 . Also, the electrodes  36  can be mounted externally to the patient&#39;s abdominal surface. 
     The electrodes  36  can be attached to the patient&#39;s abdominal surface and/or uterus  38  using biocompatible glue or tissue adhesive, or by suction or other self-affixing electrodes. In one embodiment, the electrodes  36  can be standard silver chloride (AG2Cl) electrodes, EEG electrodes, suction electrodes, or needle electrodes. In some embodiments, the system  22  can include between one and fifty electrodes  36  (e.g., equal to the number of lead wires  34 ). Different electrodes  36  can be positioned at various locations in or around the patient&#39;s uterus  38 , where some or each of the electrodes  36  causes tonic and/or phasic effects according to the electrical stimulus applied through them. For example, one or several electrodes  36  can act as a local pacemaker for eliciting contractions, while one or several other electrodes  36  can cover one or many different portions of the uterus  38  for eliciting global tonic or tetanic contractions. In addition, in some embodiments, the electrodes  36  can consist of platinum-iridium metals, so as to reduce the possibility of tissue lesions ( 12 ). 
       FIGS. 12A-12C  illustrate a patient&#39;s uterus  38  in three different conditions.  FIG. 12A  shows a naturally contracting uterus  38  post-partum. Forceful and spontaneous tonic contractions can prevent blood loss.  FIG. 12B  shows a uterus  38  which is not contracting postpartum due to uterine atony. The lack of tonic contractile activity allows the uterus to bleed out, threatening the life of the patient.  FIG. 12C  shows the uterus  38  with atony and uterine rupture treated effectively (i.e., forcefully contracted) using electrical tonic stimulation. As shown in  FIG. 12C  the uterus  38  has been outfitted with electrodes  36  (trans-vaginally) so that the system  22  can output stimulated current (i.e., through the lead wires  34 ) for tonic activity using electrical frequencies greater than or equal to about 5 Hz. The artificially-stimulated tonic contractions can help reduce, stop and/or manage the blood loss. In one embodiment, the stimulated current can be output to the patient for a duration greater than about 10 seconds. In some embodiments, the pulse train durations can be up to about 30 minutes long. 
     In addition, the system  22  can be used in conjunction with other devices, methods, systems, and treatments for postpartum hemorrhage, uterine atony, and bleeding or coagulation problems, including but not limited to oxytocin, prostaglandins, misoprostol, prepidil, ergot alkyloids, tamponades, balloon tamponades, sponges, clamps, manual uterine massage and manipulation, sutures, bio-compatible adhesives, cauterization, and/or pharmaceutical coagulants. 
     In some embodiments, the system  22  can include one or more devices for positioning the electrodes  36  within a patient&#39;s uterus, as described below. For example, in some embodiments, the system  22  can include a balloon electrode array device  54 , as shown in  FIGS. 13-14B , outfitted with the lead wires  34  and the electrodes  36 . The balloon electrode array device  54  can be used to assist with reducing blood flow from the uterus  38  during postpartum hemorrhage through mechanical pressure as well as electrical stimulation (i.e., using stimulation frequencies greater than or equal to about 5 Hz for inducing tonic or tetanic contractions). Also, in some embodiments, the balloon electrode array device  54  can be used to assist with inducing contractions in laboring women (i.e., using conventional stimulation frequencies for inducing stimulated phasic contractions). 
     The balloon electrode array device  54  can include a balloon, or concentric balloons, which can be inserted trans-vaginally and trans-cervically. The balloon electrode array device  54  can be inflatable (in order to apply mechanical pressure to the inside wall of the uterus  38 ) and can alternatively or simultaneously apply electrical stimulation to contract uterine muscle and/or arteries. The inflation of the balloon can provide a reliable contact of the attached stimulating electrodes  36  to the internal surface of the uterus  38 . In one embodiment, the balloon electrode array device  54  can be a dual balloon electrode array and internal pressure intrauterine device, as shown in  FIG. 13 . In one embodiment, the balloon electrode array device  54  can include an outer balloon  56 , an inner balloon  58 , a set of insulated lead wires  34 , a semi-rigid core  60 , an inflation/wiring access tube  62 , a set of electrodes  36 , and a drainage tube (not shown). 
     In some embodiments, the outer balloon  56  can be made of latex, rubber, silicone, or another biocompatible stretchable polymer or plastic. The outer balloon  56  can be fitted on its outer surface with an arrangement of one or more electrodes  36 , which can be distributed evenly about a portion of the outer surface, as shown in  FIG. 13 . The number of electrodes  36  can be varied in different embodiments. A conductive portion of the electrodes  36  can protrude through the outer surface to an inner surface of the outer balloon  56 . 
     In some embodiments, the inner balloon  58  can be made of the same material as the outer balloon  56  (e.g., latex, rubber, silicone, or another biocompatible stretchable polymer or plastic). The inner balloon  58  can be airtight and watertight and can be inflated with an inflating material such as a liquid or a gas (e.g., saline, water, or air), as shown in  FIG. 14A . Inflation of the inner balloon  58  can cause the outer balloon  56  to also expand. In one embodiment, the balloon electrode array device  54  does not include the inner balloon  58 , and the outer balloon  56  can be watertight, airtight, and inflatable (i.e., as a single balloon electrode array and internal pressure intrauterine device). 
     The set of insulated lead wires  34  can equal the number of electrodes  36 , with each individual lead wire  34  carrying electrical stimulation current to an individual electrode  36  fitted in, on, and/or through the outer balloon  56 . In one embodiment, each lead wire  34  can be connected to its respective electrode  36  via the conductive portion of the electrode  36  protruding through the outer balloon  58 . In addition, the set of lead wires  34  can be positioned in between the inner balloon  58  and the outer balloon  56  (i.e., along the outside of the inner balloon  58  and on the inside of the outer balloon  56 ), so that the lead wires  34  do not come into contact with the patient&#39;s uterus  38 . 
     The semi-rigid core  60  can be rigid enough to facilitate the insertion of the device  54  through the vaginal canal, through the cervix, and into the intrauterine cavity (i.e., in a deflated state, as shown in  FIG. 14A ), but not so rigid as to cause the balloon electrode array device  54  to perforate the uterine tissue when inserted into the uterus  38 . In some embodiments, the semi-rigid core  60  can be hollow, flexible tubing made of rubber, plastic, Tygon®, or other similar materials. Also, in one embodiment, the balloon electrode array device  54  is capable of being placed into the uterus manually by hand without requiring the semi-rigid core  60 . 
     The inflation/wiring access tube  62  can serve as a conduit for introducing the inflating material into the inner balloon  58  (or the outer balloon  56  in some embodiments) and for at least partially routing the set of lead wires  34  from the balloon electrode array device  54  to an external electrical current and voltage source (e.g., indirectly to the current source  26  through the biphasic converter  32  of the system  22 , as described above). The drainage tube (not shown) can be used for monitoring and measuring blood flow from the uterus  38 . In some embodiments, the balloon electrode array device  54  may not include the drainage tube. 
     As described above, electrical muscle stimulation can provide a way to specifically apply different contractile effects locally on the uterus  38 . The balloon electrode array device  54  (or the other electrode array devices described below) can be used with the system  22  to aid in stimulating uterine contractions at a controllable rate and a controllable strength, as determined by the user, for example, to help produce more contractions or more powerful contractions for efficient and safer deliveries for women in labor or to help incite life-saving uterine contractions in critical hemorrhaging patients after delivery to help treat uterine atony. In the case of hemorrhage and uterine atony, the applied pressure to the cervical area  46 , vaginal area  48  and/or intrauterine cavity  44  as a result of inflating the outer balloon  60  can act as an external aid to help control bleeding while the stimulation currents can help incite the patient&#39;s natural response to control bleeding (i.e., through tonic contractions of the uterine muscles). Further, in some embodiments, the balloon electrode array device  54  can be used to aid in cervical ripening to help induce labor. The inflated balloon electrode array device  54  can apply pressure to the cervix  46  to help soften the cervix and incite dilation. 
     In some embodiments, the system  22  can include a ring electrode array device  64 , as shown in  FIGS. 15A-16B . The ring electrode array device  64  can be a flexible ring outfitted with lead wires  34  and electrodes  36  and inserted trans-vaginally for assisting with reducing blood flow from the uterus  38  during postpartum hemorrhage through electrical stimulation (i.e., using stimulation frequencies greater than or equal to about 5 Hz for inducing tonic or tetanic contractions). Also, in some embodiments, the ring electrode array device  64  can be used to assist with inducing contractions in laboring women (i.e., using conventional stimulation frequencies for inducing stimulated phasic contractions). 
     The ring electrode array device  64  can include a ring  66 , a set of electrodes  36 , and a set of insulated lead wires  34 . The ring  66  can comprise ring-shaped or torus-shaped rubber, latex, silicone, Tygon®, or a similar medical grade flexible material which is biocompatible. The set of electrodes  36  can be affixed to the outer surface of the ring  66 , or embedded within or incorporated into the ring material so that the electrodes  36  are exposed at an outer surface of the ring  66 . The lead wires  34  can be completely external to the ring material or partly affixed to or embedded in the ring material. In some embodiments, the set of lead wires  34  can be separately coupled directly to the system  22  (e.g., to the biphasic converter  32 ). In other embodiments, the set of lead wires  34  can be separately coupled to a lead cable connector  68 , as shown in  FIG. 15A , which can be permanently or releasably coupled to the system  22 . For example, the ring electrode array device  64  can be disposable so that, after stimulation, the lead wires  34  can be disconnected from the lead cable connector  68  and the entire device  64  disposed of. 
     In other embodiments, some or all of the lead wires  34  can be bundled into an applicator  70 , as shown in  FIGS. 16A and 16B , and coupled to the system  22  (either directly or via the lead cable connector  68 ). The applicator  70  can be a rigid or semi-rigid cylindrical probe (made of metal, rigid plastic, etc.) and, in some embodiments, can be coupled to the ring  66 . The applicator  70  can be permanently coupled to the ring  66  (e.g., by an affixing structure  71 , as shown in  FIG. 16B ) or can be detached from the ring  66  and removable. In addition, in one embodiment, the ring  66  can be collapsed into the applicator  70  or around an outside portion of the applicator  70 . For example, the ring can be collapsed into the applicator  70  and the lead wires  34  can be bundled into the applicator  70  for ease of insertion trans-vaginally. If the applicator  70  is not used, the ring  66  can be inserted manually by hand, for example by first collapsing the ring  66  manually. 
     The ring  66  can be positioned in the vaginal canal against the cervix  46  or fornix during application of electrical stimulation (i.e., using stimulation frequencies greater than or equal to about 5 Hz) in order to allow electrical current to flow between adjacent electrodes  36 , and indirectly through the uterus  38  and/or through the uterine artery, thus initiating contractile activity of the uterus  38  or arteries sufficient to reduce bleeding (e.g., during uterine atony or postpartum hemorrhage). If the applicator  70  is permanently coupled to the ring  66 , as shown in  FIG. 16B , it can remain within the vaginal canal during electrical stimulation of the electrodes  36 . If the applicator  70  is detachable from the ring  66 , as shown in  FIG. 16A , it can be removed prior to electrical stimulation, if desired. In some embodiments, the device  64 , including the applicator  70 , can be disposable. In other embodiments, at least some components of the device  64 , such as the applicator  70 , can be sterilizable for multiple uses. 
     In addition, the ring electrode array device  64  can be capable of delivering medication (i.e., via absorption) to the uterus  38  or surrounding tissue, simultaneous to the uterine electrical stimulation. The medication can be impregnated into and gradually released from the ring  66 . 
     In some embodiments, the system  22  can include an electrode probe device  72 , as shown in  FIGS. 17A-17C . The electrode probe device  72  can be a rigid or semi-rigid cylindrical probe  74 , outfitted with the electrodes  36  at one end and the connecting lead wires  34  within the probe  74  extending out at another end and inserted trans-vaginally for assisting with reducing blood flow from the uterus  38  during postpartum hemorrhage through electrical stimulation (i.e., using stimulation frequencies greater than or equal to about 5 Hz for inducing tonic or tetanic contractions). Also, in some embodiments, the electrode probe device  72  can be used to assist with inducing contractions in laboring women (i.e., using conventional stimulation frequencies for inducing stimulated phasic contractions). 
     The electrode probe device  72  can include a probe  74  comprising rubber, latex, Tygon®, metal, plastic, or a similar material, generally in the shape of a hollow or substantially solid cylinder. The electrode probe device  72  can include electrodes  36  affixed to an outer surface end of the probe  74 . The electrodes  36  can be embedded within or incorporated into the probe  74  so that the electrodes  36  are exposed at the outer surface end of the probe  74 . In addition, the electrode probe device  72  can include insulated lead wires  34  for transmitting electrical current to the electrodes  36 . The lead wires  34  can be partially coupled to or embedded in the probe  74 . For example, the lead wires  34  can be routed through a hollow tube within the probe  74  so that one end of each lead wire  34  is attached to an electrode  36  and another end of each lead wire  34  is coupled to an electrical lead cable (e.g., similar to the lead cable connector  68 , as shown in  FIG. 15A , connected to the system  22 ). In addition, all or at least some of the lead wires  34  can be bundled together and routed through a hollow tube within the probe  74 . 
     The electrode probe device  72  can be positioned through the vaginal canal so that the electrodes  36  are positioned against or into the tissues of the cervix or fornix, or through the cervix  46  into the uterine cavity and positioned directly against or into the inner uterine wall. Application of electrical stimulation (i.e., using stimulation frequencies greater than or equal to about 5 Hz) can allow electrical current to flow between adjacent electrodes  36 , and thus flow indirectly or directly through the uterus and/or through the uterine artery, thus initiating contractile activity of the uterus or arteries sufficient to reduce bleeding (e.g., during uterine atony or postpartum hemorrhage). 
     In some embodiments, the entire device  72  can be disposable. In other embodiments, at least some components of the device  72  can be sterilizable for multiple uses. In one embodiment, as shown in  FIG. 17A , the probe  74  can include a single spiral electrode  34  protruding from one end, and lead wires  34  routed through a hollow portion of the probe  74 . In another embodiment, as shown in  FIG. 17B , the probe  74  can include one or more “bar” or “rod” electrodes  36  protruding from one end. In yet another embodiment, as shown in  FIG. 17C , the probe  74  can include one or more “barb” or “needle” electrodes  36  protruding from one end. In some embodiments, multiple probes  74  can be used simultaneously, as needed, to apply sufficient electrical current in a sufficient number of locations on the uterus, cervix, or fornix in order to produce an adequate uterine contractile response. 
     In addition, the electrode probe device  72  can be capable of delivering medication (i.e., via injection) to the uterus  38  or surrounding tissue, simultaneous to the uterine electrical stimulation. 
     In some embodiments, the system  22  can include a mesh electrode array device  76 , as shown in  FIGS. 18A-20C . The mesh electrode array device  76  can comprise an array of electrodes  36  in the form of a “net,” “web,” or “mesh”  78  of electrically non-conductive, flexible, and/or stretchable material supporting the conductive electrode elements  36  and/or conductive lead wires  34 . The mesh electrode array device  76  can be inserted trans-vaginally for assisting with reducing blood flow from the uterus  38  during postpartum hemorrhage through electrical stimulation (i.e., using stimulation frequencies greater than or equal to about 5 Hz for inducing tonic or tetanic contractions). Also, in some embodiments, the mesh electrode array device  76  can be used to assist with inducing contractions in laboring women (i.e., using conventional stimulation frequencies for inducing stimulated phasic contractions). 
     The non-conductive mesh material  78  can provide a framework to non-conductively connect or link each electrode  36  to one or more other electrodes  36 . The non-conductive mesh material  78  can be a supporting substrate having one or more segments constructed of flat, rounded, cylindrical, and/or other-shaped material. In some embodiments, the non-conductive mesh material  78  can comprise silicone, latex, rubber, plastic, nylon, etc., so that the device  76  can stretch and twist effectively in multiple directions. In addition, the non-conductive mesh material  78  can be fabricated to include a constant or variable framework or base structure, including square, hexagonal, triangular, and/or other mesh shapes, as shown in  FIGS. 18A and 18B . 
     The mesh electrode array device  76  can expand (e.g., substantially open up, unfold, stretch out, etc.) to a size sufficient to cover, envelope, or encircle the uterus  38 . The device  76  can expand into a general sphere, general ovoid, or general cigar shape, having dimensions between about 5 centimeters major or minor diameter up to about 50 centimeters major or minor diameter. For example, in one embodiment, the device  76  can be fabricated to form-fit snugly around the entire outer surface of a uterus  38  before and/or after delivery of the fetus by cesarean-section. In addition, the non-conductive mesh material  78  can include gaps, slits, or other openings positioned therein in order to accommodate uterine arteries and various ligaments when deployed onto the uterus  38 . The device  76  can also be specifically fabricated in various sizes in order to accommodate, as appropriate, either a small, medium, or large size uterus  38 . 
     The electrodes  36  can be positioned along and within the non-conductive mesh material  78  at nodes of intersection of the strands or segments and/or along the length of the strands or segments. The electrodes  36  can include materials which are electrically conductive, such as metal, graphite, ceramic, polymer, or other rigid or semi-rigid and conductive substances. In some embodiments, as shown in  FIG. 19 , each electrode  36  can include a tip  80  and a housing  82  coupled together mechanically or chemically. The tip  80  (e.g., a conductive portion) can be connected to or positioned on the uterine tissue for passing electrical current thereto, and the housing  82  (e.g., an electrically non-conductive portion) can be coupled to the non-conductive mesh material  78 . The housings  82  can include a rigid or semi-rigid electrically non-conductive material, such as plastic, rubber, polymer, etc., and can include passages, gaps, grooves, and/or ridges through which or into which the lead wires  34  can pass to electrically connect with the tips  80 . As shown in  FIG. 19 , the electrodes  36  can include one or more shapes, such as needles, spikes, point, nubs, grommets, nipples, disks, or any other form, feature, or shape to provide sufficient electrical conductivity and connectivity between the electrodes  36  and the uterine tissue, and to transmit electrical current to/from the electrodes  36  and uterine tissue. The above-described shapes of electrodes  36  can be incorporated into one or more of the devices  54 ,  64 ,  72 ,  76  in some embodiments. 
     The mesh electrode array device  76  can include sufficient tensile strength and elastic force so that a physician can fully and manually deploy it around and onto the uterus  38  with relative ease by hand with minimal risk of injury to the patient and to the physician during handling and deployment. In addition, the electrodes  36  can be oriented in such a way within and on the non-conductive mesh material  78  so that the tips  80  are directed toward the uterine tissue when the device  76  is deployed (e.g., placed onto and expanded around the outer surface of the uterus  38 , for example during cesarean section). More specifically, the mesh electrode array device  76  can include sufficient tensile strength and elastic force so that when the device  76  is deployed, the electrodes  36  will rest firmly against the outer surface of the uterus  38 , or so that portions of the electrodes  36  will penetrate through an outer membrane of the outer surface of the uterus  38  (e.g., when using needle-shaped or other pointed-tip types of electrodes  36 ). 
     In some embodiments, the mesh electrode array device  76  can include pairs of electrodes  36  (e.g., each pair including a positive electrode and a negative electrode), with each pair of electrodes  36  capable of transmitting an individual, distinct electrical current through the uterine tissue. The electrodes can receive electrical stimulation current (e.g., can be electrically activated by and fed electrical stimulation current from the system  22 ) via two or more lead wires  34  (e.g., at least one positive lead wire  34  and at least one negative lead wire  34 ). 
     For example, the designated positive electrodes  36  (e.g., from the electrode pairs) can receive electrical stimulation current from a single main positive voltage lead wire  34 , and the designated negative electrodes  36  can receive electrical stimulation current from a single main negative voltage lead wire  34 , as shown in  FIG. 20A . In another example, the designated positive electrodes  36  can receive electrical stimulation current from different positive voltage lead wires  34 , which are branched off from the single main positive voltage lead wire  34 , and the designated negative electrodes  36  can receive electrical stimulation current from different negative voltage lead wires  34 , which are branched off from the single main negative voltage lead wire  34 , as shown in  FIG. 20B . In yet another example, the designated positive electrodes  36  can receive electrical stimulation current from separate, individual positive voltage lead wires  34 , and the designated negative electrodes  36  can receive electrical stimulation current from separate, individual negative voltage lead wires  34 , as shown in  FIG. 20C . 
     In some embodiments, at least some portions of the electrodes  36  (e.g., the tips  80  or other portions) of the above-described devices  54 ,  64 ,  72 ,  76 , can be fitted with, covered by, coated with, or impregnated with conductive epoxy, medication, friction-reducing compounds, or other substances for improving the electrical conductivity between the electrode  36  and the uterine tissue, for treating the patient or the uterus, for improving the effect of electrical stimulation of the uterus  38 , for improving uterine contractility, and/or for enhancing the ease with which electrodes  36  are applied to or into the uterine tissue. In addition, at least some portions of the electrodes  36  (e.g., the tips  80  or other portions) can be fitted with, covered by, coated with, or impregnated with insulating epoxy, friction-reducing compounds, or other substances (e.g., polytetrafluoroethylene, or PTFE, resin) for eliminating or reducing electrical conductivity and contact between such portions of the electrodes  36  and the uterine tissue. 
     In addition, in some embodiments, the electrodes  36  of the above-described devices  54 ,  64 ,  72 ,  76  can be temporarily covered by tabs, covers, or safety guards (not shown) for protecting the patient and user from punctures or cuts during handling prior to or during deployment of the devices  54 ,  64 ,  72 ,  76 . The safety guards can individually be removed manually upon, after, or prior to deploying the device, and can be replaced, if desired. 
     In some embodiments, the above-described devices  54 ,  64 ,  72 ,  76  or other external, internal, or transvaginally, transcervically, percutaneously, or transabdomoinally placed needles, catheters, probes, electrodes or electrode arrays may be outfitted with the cable connector  68  or a similar device in order to be coupled to the system  22  for receiving electrical stimulation current (e.g., from the biphasic converter  32 ) via a connector and cable device  84 , as shown in  FIGS. 21A-23B . The device  84  can include a lead wire connector plug  86 , an electronics connector plug  88 , and a flexible, electrically insulated cable  90 . 
     In one embodiment, the electronics connector plug  88  can connect to the biphasic converter  32  for receiving electrical stimulation current. In another embodiment, components of the system  22  (e.g., the control module  24 , the current source  26 , the isolation unit  28 , the constant maximum current unit  30 , the biphasic converter  32 ) can be housed in a single electronics box (not shown) and the electronics connector plug  88  can be connected to the electronics box for receiving electrical stimulation current. The electrical stimulation current can be routed from the electronics connector plug  88  to the lead wire connector plug  86  via the cable  90 . In some embodiments, the plugs  86  and  88 , and the cable  90  can be permanently coupled as a single unit. In other embodiments, the plugs  86  and  88 , and the cable  90  can be releasably coupled together, for example so that some portions can be disposable and some portions can be sterilizable (e.g., using radiation, gas, and/or heat). 
     In some embodiments, the lead wire connector plug  86  and/or the electronics connector plug  88  can comprise conventional connector plugs, such as DIN connectors, BNC connectors, coaxial connectors, banana connectors, LEMO connectors, etc., for connecting to the lead wires  34  and/or the electronics box, respectively. In some embodiments, the lead wire connector plug  86  and/or the electronics connector plug  88  can comprise a pin connector array, as described below. For example,  FIG. 21A  illustrates the lead wire connector plug  86  and the electronics connector plug  88  as a generic connector and a pin connector array, respectively.  FIG. 21B  illustrates both the lead wire connector plug  86  and the electronics connector plug  88  as pin connector arrays. 
     The pin connector array can include a plurality of pin connectors, as shown in  FIGS. 22A and 22B . In one embodiment, each pin connector can comprise an irregular, symmetric hexagonal shape, as shown in  FIG. 23A . For example, the hexagonal shape can take the form of an equilateral triangle of length L, with wedges (length ¼L) at each vertex of the equilateral triangle removed, as shown in  FIG. 23B . In other embodiments, the pin connectors can comprise other shapes. 
     The pin connectors can be positioned relative to each other on the pin connector array in one or more arrangements, as shown in  FIGS. 22A and 22B . For example, the “flip flop” arrangement illustrated in  FIG. 22B  can be substantially shorter than the “in-line” arrangement illustrated in  FIG. 22A . In addition,  FIGS. 22A and 22B  show 10 pin connectors in each pin connector array. In some embodiments, the pin connector arrays can include one to fifty or more pin connectors. 
     In one embodiment, the electronics box and/or the lead wires  34  can include corresponding male connectors for receiving the pin connectors (e.g., female connectors) of the plugs  86 ,  88 . In another embodiment, the electronics box and/or the lead wires  34  can include corresponding female connectors for receiving the pin connectors (e.g., male connectors) of the plugs  86 ,  88 . In either embodiment, the male connectors can include a cylindrical pin protruding from the general center of the hexagonal shaped connector, as shown in  FIG. 24A . The pin can include an outside diameter between about 1.245 millimeters and about 1.255 millimeters in some embodiments. The female connectors can include mating cylindrical holes for the cylindrical pins of the male connectors, as shown in  FIG. 24B . The holes can include an inner diameter between about 1.245 millimeters and about 1.255 millimeters in some embodiments. In addition, the pin connectors can be plastic, while the protruding pins can be metallic and the holes can include metallic internal sleeves. The pins and internal sleeves can also comprise other conductive materials in some embodiments. In addition, the pin connector arrays or the individual pin connectors can include one or more locking mechanisms. In one embodiment, the locking mechanism, either on the plastic or the conductive portions of the pin connectors, can substantially lock the pin connector arrays in place when the female connectors and the male connectors are connected. Once connected, the female connectors and the male connectors can be broken or disabled when separated, ensuring one-time use of the pin connector arrays. 
     In some embodiments, the cable  90  can include a plurality of electrically conductive materials or wires (e.g., metal, carbon-based elements, etc.). The electrically conductive wires can be substantially flexible and bunched, threaded, braided, or twisted through the cable  90 . The electrically conductive wires can be electrically insulated externally by materials such as plastic, rubber, silicone, or other non-conductive media. Each hole in the pin connector array (of the female connectors) at the plug  86  can be associated with a separate electrically conductive wire, which can be connected to an associated pin or sleeve (of the male connectors or the female connectors, respectively) at the plug  88 . 
     In some embodiments, the connector and cable device  84  can include electrical circuitry, computer software or hardware, logic circuits, instructions, codes, and/or programs stored in memory and executable by the electrical circuitry, which can serve one or more of following functions: measuring or communicating electrical impedance values (in the patient, between electrodes  36 , and/or between the patient and electrodes  36 ); determining or communicating the electrical or physical integrity of the cable  90 , the plugs  86 ,  88 , and/or any of the electrodes  36 ; communicating an embedded serial code, license code, model number, or other electronically stored or coded information about the connector and cable device  84  to the electronics in the system  22 ; and preventing the operation of providing electrical stimulation current if cable or plug portions become detached, separated, broken, compromised, or otherwise altered, or if the serial code is not correct or identifiable by the system  22 . 
     The present invention has been described in terms of one or more preferred embodiments, and it should be appreciated that many equivalents, alternatives, variations, and modifications, aside from those expressly stated, are possible and within the scope of the invention. 
     The entire disclosure of each patent and publication cited herein is incorporated by reference, as if each such patent or publication were individually incorporated by reference herein. Unless defined otherwise, technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Singleton et al., Dictionary of Microbiology and Molecular Biology 3rd ed., J. Wiley &amp; Sons (New York, N.Y. 2001); March, Advanced Organic Chemistry Reactions, Mechanisms and Structure 5th ed., J. Wiley &amp; Sons (New York, N.Y. 2001), and Sambrook and Russel, Molecular Cloning: A Laboratory Manual 3rd ed., Cold Spring Harbor Laboratory Press (Cold Spring Harbor, N.Y. 2001), provide one skilled in the art with a general guide to many of the terms used in the present application. 
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