System and method of delivering local anesthesia

Abstract

A catheter and introducer needle assembly is provided including a catheter adapter at its proximal end. The catheter adapter includes a side port in fluid communication with the catheter. A septum is located in the proximal end of the catheter adapter proximal of the side port. The introducer needle is connected at its proximal end to a needle hub and includes at least one notch formed therein in communication with the introducer needle lumen. The notch is formed in the needle such that blood can flow into the open distal end of the needle, through the lumen in the needle and through the notch into the catheter lumen (specifically, the annular space between the outside of the introducer needle and the inside of the catheter and catheter adapter). Thereafter, the blood can flow through the annular space and then through the side port and extension tube that extends from the catheter adapter. Similarly, liquids delivered to the side port flow to the annular space between the needle and the catheter, through the notch into the lumen within the needle, and out of the tip of the needle. Liquid anesthesia thus can be delivered to the patient's tissue surrounding the needle tip be delivering the liquid through the side port. An electrical connection may be provided to the needle via the needle hub to. carry an electrical charge to the patient's tissue. After withdrawing the needle from the catheter, the catheter remains in place, with the tip of the catheter disposed in the tissue being anesthetized. The clinician may provide additional anesthesia via the catheter through the extension tube set.

1 . A method for delivering anesthesia including: 
 providing a needle with a notch, a tip and a central bore passing through the needle and creating a fluid flow path between the notch and the tip, wherein the needle is formed of a material capable of conducting an electrical charge;    providing a catheter having a proximal end and a distal end disposed slidingly about the needle such that an annular space is formed between at least a portion of the needle and the catheter and the tip of the needle extends out of the distal end of the catheter;    wherein the needle and catheter form a catheter assembly;    inserting the catheter assembly into tissue to be anesthetized;    delivering an electrical charge to the needle, whereby the tissue in contact with the tip receives the charge; and    delivering anesthesia into the annular space such that anesthesia flows through the annular space, through the notch, through the central bore and out the tip of the needle.    
     
     
         2 . The method of  claim 1  further including: 
 withdrawing the needle from the catheter; and    delivering additional anesthesia, at selected times, to the tissue through the catheter.    
     
     
         3 . The method of  claim 2  wherein a catheter hub is provided connected to the catheter, the method further including affixing the catheter hub to the patient.  
     
     
         4 . The method of  claim 3  wherein wings are attached to the catheter hub and the hub is attached to the patient by taping at least the wings to the patient's skin.  
     
     
         5 . The method of  claim 3  wherein an extension tube is attached to the hub, and wherein anesthesia is delivered to the hub via the extension tube.  
     
     
         6 . The method of  claim 1  wherein the catheter is translucent or transparent.  
     
     
         7 . The method of  claim 1  wherein the notch is disposed near the tip of the needle within the catheter.  
     
     
         8 . The method of  claim 1  wherein a catheter hub is provided attached to the catheter and wherein the catheter hub has a side port such that a fluid path is formed between the side port and the catheter.  
     
     
         9 . The method of  claim 8  wherein the catheter forms a seal with the needle near the tip distal to the notch.  
     
     
         10 . The method of  claim 1  wherein the notch is disposed within the catheter adapter,  
     
     
         11 . The method of  claim 1  wherein the needle, excluding its tip, is coated with a lubricant that is an electrical insulator.  
     
     
         12 . A catheter and introducer needle assembly for use in delivering anesthesia to human tissue including: 
 a catheter having a proximal end and a distal end, which catheter is formed of a material that is an electrical insulator;    catheter adapter in fluid communication with the catheter and having a proximal end and a distal end connected to the proximal end of the catheter, the catheter adapter including a side port in fluid communication with the catheter adapter;    a source of anesthesia selectively engaged to the side port;    an introducer needle having a proximal end and a distal end disposed inside the catheter;    a needle hub having a proximal end and a distal end connected to the proximal end of needle; and    an elastomeric septum disposed in the catheter adapter and located proximal of the side port.    
     
     
         13 . The catheter and introducer needle assembly of  claim 12  further comprising a needle shield removably engaged to the catheter adapter for engaging the tip of the needle as it is withdrawn from the septum.  
     
     
         14 . The catheter and introducer needle assembly of  claim 12  wherein the introducer needle defines a notch therein defining a notch distance between a proximal end of the notch and the distal end of the introducer needle, and the septum is equal to or longer than the notch distance.  
     
     
         15 . The catheter and introducer needle assembly of  claim 12  further comprising an electrical lead connected to the needle.  
     
     
         16 . A method for delivering anesthesia including: 
 providing a needle formed of a material capable of conducting an electrical charge;    providing a catheter having a proximal end and a distal end slidingly disposed about the needle such that the tip of the needle extends out of the distal end of the catheter;    providing a closed system access in fluid communication with the catheter;    wherein the needle and catheter form a catheter assembly;    inserting the catheter assembly into tissue to be anesthetized;    delivering an electrical charge to the needle, whereby the tissue in contact with the tip receives the charge delivering fluid to the catheter via the closed system access port.    
     
     
         17 . A method for delivering anesthesia including: 
 providing a needle with a notch, a tip and a central bore passing through the needle and operably connecting the notch and the tip;    providing a catheter having a proximal end and a distal end disposed slidingly about the needle such that an annular space is formed between at least a portion of the needle and the catheter and the tip of the needle extends out of the distal end of the catheter;    wherein the needle and catheter form a catheter assembly;    inserting the catheter assembly into tissue to be anesthetized; and delivering anesthesia into the annular space such that anesthesia flows through the annular space, through the notch, through the central bore and out the tip of the needle.    
     
     
         18 . A method for delivering anesthesia including: 
 providing a needle with a notch, a tip and a central bore passing through the needle and creating a fluid flow path between the notch and the tip, wherein the needle is formed of a material capable of conducting an electrical charge;    providing a catheter having a proximal end and a distal end disposed slidingly about the needle such that an annular space is formed between at least a portion of the needle and the catheter and the tip of the needle extends out of the distal end of the catheter and the notch is disposed within the catheter;    wherein the catheter electrically insulates the needle excluding the tip; wherein the needle and catheter form a catheter assembly;    inserting the catheter assembly into tissue to be anesthetized;    delivering an electrical charge to the needle, whereby the peripheral nerve tissue near the tip receives the charge, thereby exciting the enervated tissue, causing a response and thereby identifying the location of the nerve; and    delivering anesthesia into the annular space such that anesthesia flows through the annular space, through the notch, through the central bore and out the tip of the needle.    
     
     
         19 . A catheter and introducer needle assembly for use in delivering anesthesia to human tissue including: 
 a catheter having a proximal end and a distal end;    a catheter adapter in fluid communication with the catheter, the catheter adapter having a seal;    a closed system access port operably attached to the catheter adapter such that the closed system access port is in fluid communication with the catheter adapter;    an introducer needle having a proximal end and a distal end slidingly disposed inside the catheter, wherein a portion of the needle is disposed within the seal; and    a needle hub having a proximal end and a distal end connected to the proximal end of needle; and    an electrical lead operably connected to the needle;    wherein, when the introducer needle is withdrawn from the catheter adapter, the seal prevents fluid flow through the seal.    
     
     
         20 . The catheter and introducer needle assembly of  claim 19  wherein the seal includes a septum disposed in the catheter adapter and located proximal of the catheter.  
     
     
         21 . The catheter and introducer needle assembly of  claim 19  wherein the needle includes a central bore extending to the distal end of the needle, and a notch disposed in the needle in fluid communication with the central bore.  
     
     
         22 . A catheter and introducer needle assembly for use in delivering anesthesia to human tissue including: 
 a catheter having a proximal end and a distal end;    a catheter adapter in fluid communication with the catheter;    an access port operably attached to the catheter adapter such that the access port is in fluid communication with the catheter adapter;    an introducer needle having a proximal end, a distal end and a notch, the needle being slidingly disposed within the catheter; and    a needle hub having a proximal end and a distal end connected to the proximal end of needle; and    an electrical lead operably connected to the needle;    wherein, when the introducer needle is withdrawn from the catheter adapter, a seal is formed to prevent fluid flow through the seal.    
     
     
         23 . The catheter and introducer needle assembly of  claim 22  wherein the needle is disposed within the access port before it is withdrawn from the catheter adapter.