Apparatus and Method for Limiting Access to a Drug Pump Septum
Publication Date: 2003-Sep-25
The IP.com Prior Art Database
A keying system is used to permit entry of a needle into one septum (opening) in a drug delivery catheter and prevent entry of the needle in another septum (opening) of a drug reservoir. The drug delivery catheter and drug reservoir are parts of a medical device such as a drug infusion pump. Specific needles are "keyed" to a counterpart septum so that each needle can only be inserted into its counterpart septum. Each septum may have notches or shapes in the inner wall and each counterpart needle will have a longitudinal matching groove or grooves that allow entry of the needle into its counterpart septum. This keying system prevents accidentally delivery of fluids into a wrong fluid chamber or delivery line.
Implantable drug infusion pumps are becoming more prevalent in the treatment of chronic pain and movement disorders. These pumps commonly are designed with two septa or openings, one septum may be used to fill the drug reservoir and the other septum may be used to access the drug delivery catheter. Access to the catheter may be needed for diagnostic purposes, for administering secondary drugs or for clearing a blocked catheter. If a physician were to accidentally inject a drug into the catheter septum rather than the intended reservoir, the patient may be seriously harmed by the uncontrolled delivery of the drug. It is also desirable to prevent an accidental entry of a needle into the drug reservoir when the intention is, instead, to access the catheter port. Therefore, there is a need to selectively discriminate the entry of a needle into one septum from entry into another septum.
The solution to the above-described problem is to provide septa (openings) that permit only specifically conformed needles having predetermined notches that “key” or match the corresponding protrusions in each septum. This matched notching system allows only a needle with a predetermined notch shape or pattern to enter the corresponding septum.
FIGS. 1A and 1C show an example system, wherein a first septum 10 and a second septum 40 are placed in different locations of a drug infusion pump 100. FIG. 1A shows a first septum (opening) 10 having two inward notches 20 and 30. The notches 20 or 30 shown are in the shape of rectangular inwardly directed notches. It can be appreciated that the notch shapes can be other shapes, for instance, triangles or semi-circles.
FIG. 1B shows a picture of a needle 5 with an optional tip 7 and lumen opening 8 and a longitudinal groove 35. This groove must be sized to be larger than notch 30 so that the needle 5 may be inserted through the septum 10. In addition, the needle 5 must have a longitudinal groove (not shown) on the other...