Abstract:
A precordial overlay and dual backing assembly is expeditiously affixed together in a manner which allows it to be packaged in an unalterable form. When needed to obtain an ECG reading, the assembly is removed from the packaging and the precordial overlay swiftly separated from the dual backing. The dual backing is discarded. The precordial overlay is quickly and accurately positioned on a patient, The precordial overlay of the assembly comprises an elongated band having a first and a second generally rectangular-shaped sections joined together by an intermediate section. All three sections have at least one cut-out to receive an adhesive-backed electrode assembly. The dual backing of the assembly is similarly shaped and comprises a thin intermediate substrate with release agents on each side and a thin lower substrate with a release agent on a top side. The intermediate substrate further has a set of bent-back flaps, each flap positioned to receive an underside of one of the electrode assemblies. The flaps and the release agents of the dual backing allow the precordial overlay to be swiftly disassembled from the dual backing and used to obtain reliable test results in short order.

Description:
FIELD OF THE INVENTION 
     This invention relates to a precordial overlay and dual backing assembly. For particularly, the invention relates to a precordial overlay and backing assembly which is expeditiously affixed together in an unalterable form for packaging purposes, yet swiftly disassembled for use. The precordial overlay is used to quickly and properly position electrodes on a patient as part of a electrocardiographic analysis. 
     BACKGROUND OF THE INVENTION 
     Electrocardiograms, commonly referred to as either ECGs or EKGs, are obtained from a patient as a diagnostic aid. They are often obtained as part of a routine physical exam conducted in a doctor&#39;s office. They are also obtained by emergency medical personnel on-site when responding to emergency runs initiated by a patient or concerned individual. A reliable reading is obtained if the personnel administering the test properly positions electrodes on the patient&#39;s chest. This can be challenging in an emergency situation given the circumstances under which the test is administered. 
     My U.S. Pat. Nos. 5,995,861 and 6,141,575 describe precordial overlays which address the need for a quick and accurate positioning of electrodes on a patient. The precordial overlay is an elongated band shaped for positioning on a patient&#39;s chest and further includes electrodes. The elongated band has cut-outs. A plurality of electrodes are specially configured as slidable electrode assemblies. They are mounted in the cut-outs. The elongated band allows for an approximate positioning of electrodes on the patient&#39;s chest and the manner of mounting allows a sliding of each assembly with its associated electrode to a precise chest location. 
     The patented precordial overlay has gained acceptance in emergency medical units and departments across the country. Greater efficiencies, though, are always desired in manufacturing products and in using products regardless of the industry. Such is the case with my precordial overlay. In accord with this general need, there has now been developed a precordial overlay which is more quickly manufactured in a form which can be packaged and transported. The resultant assembly is unalterable in the package, yet is swiftly disassembled on-site for use. Economic savings are achieved in manufacturing. Time savings are achieved by on-site emergency medical personnel. The savings are achieved without a sacrifice in quality or reliability of the overlay. 
     SUMMARY OF THE INVENTION 
     An assembly comprises a precordial overlay and a dual backing. It is expeditiously affixed together for packaging and transportation purposes in an unalterable form. Yet, it is readily removed from the package and swiftly disassembled for use of the precordial overlay on a patient to obtain reliable ECG test results. The precordial overlay comprises an elongated band with a set of cut-outs and electrode assemblies mounted in the cut-outs. The electrode assemblies have an adhesive on an underside which is needed to hold the electrode in place on a patient&#39;s chest during use. The dual backing of the assembly comprises thin intermediate and lower substrates similarly shaped to the elongated band. The intermediate substrate has release agent on both top and bottom sides and has a set of bent-back flaps positioned to receive the adhesive covered underside of each electrode assembly. The lower substrate has release agent on its top side. When assembled, the adhesive on the electrode assemblies contacts the bent-over flaps of the intermediate substrate and a portion of the lower substrate. The flap configuration and the release agents allow the precordial overlay to be swiftly separated in whole from the dual backing. The precordial overlay can then be used on a patient to obtain a quick and accurate positioning of the electrode assemblies. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of the precordial overlay and dual backing assembly of the invention. 
         FIG. 2  is an exploded view of the assembly of  FIG. 1  showing an elongated band and electrode assemblies of the precordial overlay as well as a thin intermediate substrate with a set of bent-over flaps and a thin lower substrate of the dual backing. 
         FIG. 3  is a side view in section taken along line  3 - 3  of  FIG. 1  showing one of the electrode assemblies in detail. 
         FIG. 4  is an environmental view showing the precordial overlay disassembled from its dual backing and positioned on a patient. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The precordial overlay and dual backing assembly of the invention is efficiently assembled for packaging and transport. The precordial overlay is readily separated from the dual backing. It is then used for quick and proper placement of electrode assemblies on a patient who is having an electrocardiographic test performed. The precordial overlay itself is primarily used by emergency medical personnel who often must quickly obtain an ECG. It can as well be used by medical personnel in a doctor&#39;s office setting as part of a routine physical examination. 
     The precordial overlay and dual backing assembly  10  of the invention is depicted in  FIGS. 1 and 2 . The precordial overlay  11  component includes an elongated band  12  and a set of electrode assemblies  13  while the dual backing  15  component includes a thin intermediate substrate  16  and a thin lower substrate  17 . Generally, the elongated band  12  of the precordial overlay is shaped to overlie a patient&#39;s chest. The electrode assemblies  13  are slidably mounted on the elongated band  12 . The dual backing  15  is for packaging purposes with particular attention given to a need for a swift separation from the precordial overlay  11  without damage. 
     A highly preferred embodiment of the invention is depicted in  FIG. 1 . As apparent, five electrodes are slidably positioned in linear cut-outs while one electrode is slidably positioned in an oval cut-out. The precordial overlay&#39;s configuration allows emergency medical personnel to place the elongated band onto the patient&#39;s chest, as seen in  FIG. 4 , in the correct gross approximate location and then readily fine adjust the individual electrodes&#39; precise chest location. A detailed description now follows of the components of the assembly  10  of the invention. 
     With particular reference to  FIG. 2 , the precordial overlay&#39;s elongated band  12  is thin and substantially flat. It is also sufficiently flexible to follow the contour of a patient&#39;s chest. It has a first generally rectangular-shaped section  20 , a second generally rectangular-shaped section  21  and an intermediate section  22 . The two generally rectangular-shaped sections are off-set from one another and extend in the same longitudinal direction. The intermediate section  22  connects the first and second generally rectangular-shaped sections  20  and  21 . The shape of the band generally coincides with the area of the chest where electrodes must be positioned to obtain a reliable ECG. 
     The exact size of the elongated band is dependent on the size of the patient being tested, taking into consideration sex, age and body weight. Generally, because of the electrodes adjustability as described below, two sizes of the precordial overlay are adequate. A larger size is used for adults and a smaller size is used for children under the age of 14. Routine experimentation only is needed to determine the exact dimensions of the elongated band to meet its stated objectives. 
     The elongated band forming a part of the precordial overlay is made of a non-conductive material. A synthetic polymeric film is preferred because of its low material cost and capability of being given a desired shape by mass production techniques such as die-cutting. The precordial overlay of the invention is disposable primarily because the elongated band is capable of being produced at a reasonable cost. Polyethylene, polypropylene, polyvinylchloride, polyacrylate, polytetrafluoroethylene, nylon and polyester are examples of suitable polymeric films. A polyester film available as Mylar is particularly preferred. 
     Discreet cut-outs are provided in the body of the elongated band to accommodate the electrode assemblies. Six electrode assemblies  13  are slidably mounted in the elongated band  12 . Each of the electrode assemblies includes an electrode identified by its medical nomenclature V 1 -V 6 . 
     Linear cut-outs  25  and  26  in the first generally rectangular-shaped section  20  of the elongated band  12  are configured to receive electrodes V 1  and V 2  and allow their assemblies to laterally slide for precise positioning purposes. The cut-outs  25  and  26  are approximately centered in the first section and run in the same lateral direction. One cut-out can be used in place of the two cut-outs, though is less preferred. Each cut-out  25  and  26  has a length to allow at least about 1.0 inch of electrode lateral movement. Preferably, the cut-outs are each about 1.5 inches to about 2.5 inches long and about 0.25 inches to about 0.5 inches wide. 
     Linear cut-outs  27 ,  28  and  29  in the second generally rectangular-shaped section  21  are configured to receive electrodes V 4 , V 5  and V 6  and their assemblies in a manner which allows them to slide within their respective cut-out until properly positioned for the particular patient. Cut-outs  27 ,  28 , and  29  each has a length to allow at least about 1.0 inch of electrode lateral movement. Preferably, cut-out  27  is about 1.5 inches to about 2.0 inches long. Preferably, cut-out  28  is about 1.5 inches to about 2.5 inches long. Preferably, cut-out  29  is about 1.5 inches to about 5.5 inches long. All three cut-outs are about 0.25 inches to about 0.5 inches wide. Each cut-out allows only limited lateral movement of its associated electrode assembly. One cut-out extending the length of cut-outs  27 - 29  can be used instead of the three cut-outs  27 - 29 . However, the three separate cut-outs are preferred to provide added precision in positioning of each of the electrodes V 4 , V 5  and V 6  and associated assembly. 
     The cut-out  30  in the intermediate section  22  is dimensioned to receive an electrode assembly and slidably hold it in position. The cut-out  30  is generally oval in shape with a major axis length of from about 1.5 inches to about 2.5 inches and a minor axis length of from about 1.0 inches to about 1.5 inches. This relatively small cut-out is sufficient to allow limited movement of the electrode V 3  and its associated assembly in two directions. 
     Preferably, numeric scales  31  are printed onto the elongated band  12  of the precordial overlay. The scales are located just below or above the cut-outs  25  and  26  in the first generally rectangular-shaped section  20  and the cut-outs  27 - 29  in the second generally rectangular-shaped section  21 . The numeric scales are used to record precise electrode placements in case a second reading is needed to verify an initial ECG. 
     The electrode assemblies  13  are specifically designed for use with the precordial overlay  11  of the invention. As best seen in  FIG. 3 , each assembly  13  is designed to remain in a cut-out, while allowing a sliding movement. The assembly  13  depicted includes the electrode V 6  having a conductive metal post  35 , a retention plate  36  and an underlying conductive foam disk  37 . The vertically extending metal post  35  receives a cap head of a lead or wire (not illustrated) which is connected to the electrocardiograph. The height of the electrode V 6  is sufficient to extend up through the cut-out  29  when mounted on the elongated band  12 . The underlying foam disk  37  is used for comfort reasons in that it is the part of the electrode that contacts the patient&#39;s skin during the electrocardiographic test. The disk  37  is saturated with a conducting gel. It can as well be a simple conductive metal disk. 
     Still with reference to  FIG. 3 , the V6 electrode illustrated is mounted on a non-conductive pad  38  for ease of handling purposes. The non-conductive pad is made of a synthetic foam material and has a diameter greater than the width of the cut-out in which it is mounted. It has an adhesive on its underside for adhering to the patient. As best seen in  FIG. 2 , the non-conductive pad has a pull tab  40  extending from one side. The pull tab  40  has no adhesive on its underside. Its purpose is to provide a handle means for the medical personnel using the assembly to grasp and move an electrode assembly from below the elongated band during final patient positioning. 
     An upper clear plastic sheet  41  overlies the pad  38  and surrounds the metal post  35  of the electrode V 6 . Its diameter is greater than the width of the cut-out with which it is associated. The plastic sheet  41  is secured to the electrode, such that its peripheral areas are free or unattached. The plastic sheet&#39;s function is to provide a means to slidably hold its associated electrode V 6  in the cut-out  29 . Preferably, an edge segment  42  of the clear plastic sheet  41  is bent upwardly to serve as a handle to slide the assembly along the cut-out from above the elongated band if desired. 
     lower clear plastic sheet  43  adjacent the upper clear plastic sheet  41  while also overlying the non-conductive pad  38  is preferred for electrodes V 3  and V 6 . The lower plastic sheet  43  is secured to the electrode in a manner similar to the upper plastic sheet  41 . The two clear plastic sheets are about the same in shape and size. The two plastic sheets  41  and  43  in effect trap the electrode within the cut-out while allowing a sliding movement. It should be understood that without the lower plastic sheet  43 , the non-conductive pad  38  can provide the same retention feature. However, the enhanced retention feature of the greater diameter and more rigid lower plastic sheet  43  is preferred at least for electrodes V 3  and V 6 . It has been found the enhanced retention feature is beneficial to the V3 electrode because of its associated relatively larger width cut-out and beneficial to the V6 electrode because of its relatively larger length cut-out. 
     While not apparent in the drawings, it has also been found that for packaging purposes, adhesive tape is used to tape the electrode assembly for electrode V 3  to the elongated band  12 . It is ideally placed under the overlying plastic sheet to contact the top side of the non-conductive pad and the top side of the elongated band. 
     The dual backing  15 , as seen in  FIG. 2 , comprises an intermediate substrate  16  and a lower substrate  17 . Each of the substrates  16  and  17  has substantially the same size and shape as the elongated band  12  of the precordial overlay. All are thin. As evident in  FIG. 1 , the elongated band  12 , the intermediate substrate  16  and the lower substrate  17  are configured substantially the same so that when formed into the assembly of the invention, they appear as three discreet layers, one on top of the other. 
     The intermediate substrate  16  has a release agent on its top side and its bottom side. A double sided silicone coating is preferred. Further, a set of bent backwardly flaps  45  are positioned along the length of the substrate such that each flap underlies one the cut-outs in the elongated band when the components of the invention are assembled together. The flaps  45  are created by die-cutting partial circles in the intermediate substrate and bending backwardly the cut portion at an approximate center line  46  thereof towards the free end  47  of the substrate&#39;s second generally rectangular-shaped section to create an upstanding flap. Preferably, the die-cut extends beyond the approximate center line for enhanced release. It should be apparent that the release agent on the underside of the intermediate substrate is now facing upwardly to receive the adhesive backing of an electrode assembly  13 . 
     The thin lower substrate  17  has a release agent on its top side only. This is needed since the adhesive backing of each electrode assembly extends through the hole left by the bent backwardly flaps and contacts the lower substrate. Preferably, for manufacturing reasons as explained below, a series of vacuum holes  48  extend around its periphery. 
     Grasping tabs  49  and  50  on the intermediate substrate  16  and lower substrate  17 , respectively are both located at the substrates&#39; second generally rectangular-shaped sections free end. They serve as handles to separate the dual backing from the precordial overlay at the appropriate time. 
     In manufacture, the lower substrate is placed in a die of the same shape. A vacuum is drawn to hold it in place. The same vacuum force holds the intermediate substrate directly on top of the lower substrate. With the flaps of the intermediate layer bent backwardly, the electrode assemblies are placed onto the intermediate layer so as to fully cover the top side of the bent-back flap and to overlay the open space created by bending the flap backwardly. The elongated band can now be placed over the electrode assemblies and the upper plastic sheet of each electrode assembly manipulated to extend out through a cut-out and lie flat on the elongated band. 
     The time needed to manufacture the assembly of the invention is substantially reduced, thereby achieving a cost savings. The assembly is in form ready for packaging. The components of the assembly remain together in an unalterable form. 
     Medical emergency personnel first remove the precordial overlay and dual backing assembly from its packaging. The precordial overlay is separated for immediate use by holding the grasping tabs of the dual backing and pulling the elongated band in an opposed direction. The electrode assemblies, one by one, peel away from its respective underlying flap and the lower substrate directly thereunder. It is apparent the bent backwardly flaps facilitate release of the electrode assemblies from the dual backing. They do so in a manner whereby the integrity of the individual electrode assemblies is not compromised. 
     The freed precordial overlay is then placed on a patient using well known anatomical landmarks, e.g. a sternum notch. When properly positioned on the patient&#39;s chest, the cut-outs  25  and  26  in the first section  20  overlie the patient&#39;s fourth rib and the cut-outs  27 - 29  in the second section  21  overlie the patient&#39;s fifth rib. The cut-out  30  in the intermediate section  22  overlies an intercostal area between the fourth and fifth ribs or slightly overlies the fifth rib. It should be apparent that trained medical personnel can very quickly place the precordial overlay on a patient&#39;s chest so that the six cut-outs overlie the correct chest area. It is then just a matter of laterally moving the electrode assemblies  13  so that the electrodes V 1 , V 2 , V 4 , V 5  and V 6  are precisely located as known by the medical personnel. The electrode assembly with electrode V 3  is moved laterally and longitudinally, though the precise positioning is readily accomplished. Another six electrodes used in conventional twelve lead electrocardiographic tests are not shown in  FIG. 4 . As well known, they are individually positioned at more remote body locations as currently done and are not a part of the invention. After use, the precordial overlay is discarded. 
     Having described the invention in its preferred embodiment, it should be clear that modifications can be made without departing from the spirit of the invention. It is not intended that the words used to describe the invention nor the drawings illustrating the same be limiting on the invention. It is intended that the invention only be limited by the scope of the appended claims.