Reusable medical electrode having disposable electrolyte carrier

Abstract

A medical electrode particularly suited for use as an EEG electrode comprises initially separated electrode conductor and electrolyte carrier components which are united prior to use of the electrode. The electrolyte carrier component comprises a disposable adhesive patch adhered to a disposable sponge member soaked with an electrolyte. The electrode conductor component comprises a reusable conductor ring having an affixed lead wire terminating with a plug-in device for effecting attachment to a monitoring instrument. Prior to use the electrolyte carrier components are stored in one or more evaporation resistant tray devices.

Having thus described my invention, I claim: 
     
       1. A medical electrode comprising a disposable portion and a reusable portion, said disposable portion comprising a shaped absorbent body soaked with an electrolyte and a pliant sheet member having an adhesive layer on one side thereof, said adhesive layer adhering an end of said body to said one side of said sheet member, said body protruding outwardly from said adhesive layer, said reusable portion comprising terminal means for transmitting electrical signals and readily separable from said disposable portion, said terminal means having an inside wall embracing and substantially surrounding said shaped body. 
     
     
       2. The medical electrode of claim 1 wherein said shaped body is a cylindrical body and said end adhered to said adhesive layer is disposed at one end of said cylindrical body. 
     
     
       3. The medical electrode of claim 2 wherein said terminal means uninterruptedly surrounds said cylindrical body. 
     
     
       4. The medical electrode of claim 3 wherein said terminal means comprises a ring portion having an outward projection from said adhesive layer of said sheet member which is less than the outward protrusion of said shaped body from such adhesive layer. 
     
     
       5. The medical electrode of claim 1 wherein said sheet member is an oblong sheet member. 
     
     
       6. The medical electrode of claim 5 wherein said oblong sheet member is elliptically shaped. 
     
     
       7. The medical electrode of claim 1 wherein said sheet member is a vinyl plastic sheet member. 
     
     
       8. The medical electrode of claim 1 wherein said inside wall is a metal wall. 
     
     
       9. The medical electrode of claim 8 wherein said metal wall is silver metal. 
     
     
       10. The medical electrode of claim 8 wherein the metal of said wall is chloridized. 
     
     
       11. The medical electrode of claim 1 wherein said sheet member has an edge margin surrounding said protruding body and spaced from said protruding body. 
     
     
       12. The medical electrode of claim 11 wherein a portion of said adhesive layer disposed between said shaped body and said edge margin adheres to a portion of said terminal means. 
     
     
       13. The medical electrode of claims 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 or 12 wherein said sheet member is moisture impervious. 
     
     
       14. The medical electrode of claim 13 wherein said sheet member is imperforate. 
     
     
       15. In the method of preparing a patient for monitoring electrical signals available at the body of the patient the steps comprising connecting a distal end portion of a lead wire to a monitoring instrument, connecting a proximal end portion of said lead wire to electrode terminal means for transmitting electrical signals, adhesively attaching a shaped absorbent body to an adhesive coating on a patch member, soaking said shaped body with an electrolyte, inserting said electrolyte soaked body in said electrode terminal means, and placing said soaked body in contact with the body of the patient by adhesively affixing the adhesive coating on said patch member over said terminal means to the patient. 
     
     
       16. The method of claim 15 wherein the placement of said soaked body in contact with the body of the patient comprises the additional steps of parting the hair of the patient, positioning a portion of the lead wire connected to said electrode terminal means along the part formed by parting the patient's hair, and pressing said adhesive patch member over said lead wire and onto the patient's hair to secure said electrolyte soaked body and said electrode terminal means to the body of the patient. .Iadd. 
     
     
       17.  In combination: a one-piece, imperforate and moisture impervious pliant plastic sheet;   an adhesive layer completely coating one side of said sheet;   an aggregate comprising an electrolyte and a shaped body for containing said electrolyte, said body having a planar end surface facing toward said sheet and said body being adhered to a part of said adhesive layer which is spaced from the margin of said sheet by engagement of the entirety of said planar surface with said part; and   relatively moisture impevious means providing a support having a supporting surface, said supporting surface being adhesively engaged to peripheral portions of said adhesive layer surrounding said part,   said sheet and said adhesive layer thereby cooperating with said support-providing means to seal said aggregate from the atmosphere surrounding said support-providing means. .Iaddend. .Iadd.   
     
     
       18.  In a medical electrode of the type comprising a disposable portion and a reusable portion; the improvement wherein said reusable portion comprises metal terminal means connected to an insulated lead means for attachment to peripheral equipment; and   said disposable portion comprises:   a. a one-piece, imperforate and moisture impervious pliant plastic sheet;   b. an adhesive layer completely coating one side of said sheet; and   c. an aggregate comprising an electrolyte and a shaped body for containing said electrolyte, said body having a planar end surface facing toward said sheet and said body being adhered to a part of said adhesive layer which is spaced from the margin of said sheet by engagement of the entirety of said planar surface with said part;   said reusable portion being so constructed that said terminal means may be located between said adhesive layer and the skin of a patient in engagement with said aggregate with a portion of said lead means located between said adhesive layer and the skin of the patient. .Iaddend. .Iadd.   
     
     
       19.  Apparatus for assembling a medical electrode on the skin of a patient comprising: A. means providing a relatively moisture impervious support having a supporting surface;   B. a disposable assembly removably supported by said means providing a support comprising: a. a one-piece, imperforate and moisture impervious pliant plastic sheet;   b. an adhesive layer completely coating one side on said sheet;   c. means forming a shaped body adhered to a part of said adhesive layer separated from the margin thereof for containing an electrolyte, peripheral portions of said adhesive layer surrounding said electrolyte containing means being engaged with said supporting surface so that said sheet and said adhesive layer cooperate with said support providing means to seal said electrolyte containing means from the atmosphere surrounding said support providing means; and     C. a reusable portion comprising an insulated lead wire having a metallic terminal which is uninsulated so that said disposable assembly may be removed from said support providing means and placed over the skin of a patient with said terminal covered by said sheet and also engaging said electrolyte containing means to form an electrode held to the skin of a patient by said adhesive layer. .Iaddend. .Iadd.20. A method of assembling a medical electrode onto the skin of a patient comprising the steps of:   providing a disposable assembly comprising means forming an imperforate pliant sheet of moisture impervious plastic having an adhesive layer completely coating one side thereof and further comprising means forming a shaped body adhered to a part of said adhesive layer separated from the margin thereof for containing an electrolyte;   mounting said disposable assembly onto means providing a relatively moisture impervious support with said disposable assembly removably attached to said support providing means by a marginal portion of said adhesive layer surrounding said part of said adhesive layer;   removing said disposable assembly from said support providing means when the medical electrode is to be assembled onto the skin of a patient; and   adhering said disposable assembly in contact with the skin of the patient by engaging said marginal portion of said adhesive layer to the skin with an uninsulated terminal of an insulated layer wire engaging said electrolyte containing means and held between said sheet forming means and the patient's skin. .Iaddend.