Medical Device Insertion

Abstract

Devices and methods for inserting at least a portion of a medical device in a patient are provided. Embodiments include medical device insertions that employ a plurality of insertion stages. Also provided are systems and kits for use in analyte monitoring.

What is claimed is: 
     
         1 . A method of positioning an analyte sensor, comprising:
 positioning a portion of an analyte sensor removably coupled to a sensor introducer at a first depth below a skin surface at a first velocity; and   positioning the portion of the analyte sensor without the sensor introducer at a second depth at a second velocity;
 wherein the cross-sectional area of an incision at the first depth made by the sensor introducer is greater than the cross-sectional area of the incision made by the analyte sensor at the second depth. 
   
     
     
         2 . The method of  claim 1 , wherein positioning the portion of the analyte sensor at the first depth includes piercing the skin surface at a first angle relative to the skin surface. 
     
     
         3 . The method of  claim 2 , wherein the first angle includes one of a 90 degrees relative to the skin surface or less than 90 degrees relative to the skin surface. 
     
     
         4 . The method of  claim 1 , wherein the first velocity and the second velocity are different, and further, wherein the first depth and the second depth are different. 
     
     
         5 . The method of  claim 1 , wherein the first depth is not deeper than the epidermis. 
     
     
         6 . The method of  claim 1 , wherein the analyte sensor comprises a plurality of electrodes including a working electrode, wherein the working electrode comprises an analyte-responsive enzyme and a mediator, and further, wherein at least one of the analyte-responsive enzyme and the mediator is chemically bonded to a polymer disposed on the working electrode. 
     
     
         7 . The method of  claim 6 , wherein at least one of the analyte-responsive enzyme and the mediator is crosslinked with the polymer. 
     
     
         8 . A method, comprising:
 piercing a skin surface to a first depth at a first velocity to position a portion of an analyte sensor at the first depth, wherein an incision at the first depth has a first incision cross-sectional area; and   displacing the portion of the analyte sensor to a second depth at a second velocity, wherein an incision at the second depth has a second incision cross-sectional area,
 wherein the first incision cross-sectional area is greater than the second incision cross-sectional area. 
   
     
     
         9 . The method of  claim 8 , wherein tissue trauma at the second depth is less than the tissue trauma at the first depth. 
     
     
         10 . The method of  claim 8 , wherein the analyte sensor is in fluid contact with interstitial fluid at the second depth. 
     
     
         11 . The method of  claim 8 , wherein the analyte sensor comprises a plurality of electrodes including a working electrode, wherein the working electrode comprises an analyte-responsive enzyme and a mediator, and further, wherein at least one of the analyte-responsive enzyme and the mediator is chemically bonded to a polymer disposed on the working electrode. 
     
     
         12 . The method of  claim 11 , wherein at least one of the analyte-responsive enzyme and the mediator is crosslinked with the polymer. 
     
     
         13 . A method, comprising:
 actuating a sensor insertion device to incise a skin surface with a sensor introducer and to insert a portion of an analyte sensor through the incised skin surface into subcutaneous tissue;
 wherein at least two different selected velocities are used to incise the skin surface and to insert the portion of the analyte sensor into the subcutaneous tissue; and further 
 wherein the width of an incision created by incising the skin surface using the sensor introducer is greater than a width of a subsequent incision created within the skin surface incision by driving the portion of the analyte sensor into the subcutaneous tissue. 
   
     
     
         14 . The method of  claim 13 , wherein at least one velocity differs from a second velocity by about 25% to about 90%. 
     
     
         15 . The method of  claim 13 , wherein a velocity to incise the skin surface is in the range from about 4 m/s to about 8 m/s. 
     
     
         16 . The method of  claim 13 , wherein a velocity to insert the analyte sensor through the incised skin surface into subcutaneous adipose tissue is in the range from about 0.025 m/s to about 0.5 m/s. 
     
     
         17 . The method of  claim 13 , wherein the skin surface is incised to a first depth and the analyte sensor is inserted to a second depth, wherein the second depth is greater than the first depth. 
     
     
         18 . The method of  claim 13 , wherein the analyte sensor comprises a plurality of electrodes including a working electrode, wherein the working electrode comprises an analyte-responsive enzyme and a mediator, and further, wherein at least one of the analyte-responsive enzyme and the mediator is chemically bonded to a polymer disposed on the working electrode. 
     
     
         19 . The method of  claim 18 , wherein at least one of the analyte-responsive enzyme and the mediator is crosslinked with the polymer.