Subcutaneous injection set for use with a reservoir that has a septum

Abstract

An infusion set includes a needle hub with a needle to be inserted in a through passageway of the cannula housing through a sealing surface of a soft cannula. The infusion set includes a guide for centering the needle relative to the cannula sealing surface, a dirt trap, and the through passageway, as well as a locking device for locking the cannula housing and the needle hub together to prevent inadvertent disengagement. The guide includes co-operating guide pins and guide openings and a draft angle on the needle hub. The pins are located on each side of the needle and the through passageway. The connecting tube includes an inner tube of polyethylene and shrink fitted tubing at each end suitable for a solvent bonding layer. The composite can be reinforced with monofilament strands sandwiched between the two tubular layers to prevent kinking, or the inner tube can be formed in a triangular shape. The triangular shape composite is incased in a thin polyester shrink tube.

What is claimed is:  
     
         1 . A medication infusion set comprising: 
 a base tube having an exterior surface, a proximal end, a distal end, and an inner lumen extending between the proximal and distal ends, the base tube formed of a material selected from the group consisting of polyethylene and polypropylene;    a rigid cannula having a proximal end, a distal end, and a lumen extending between the proximal and distal ends, the cannula proximal end positioned in the base tube lumen; and    a tube of a heat shrinkable material positioned on the base tube exterior surface at least in a region of the base tube in which the cannula is inserted, the heat shrinkable tube having been heat shrunk to the exterior of the base tube and compressing the base tube and the cannula together to form a seal.    
     
     
         2 . A medication infusion set in accordance with  claim 1 , further comprising: 
 a connector including a cylindrical collar having a hollow interior, a closed end, and an open end, the distal end of the rigid cannula extending through the collar closed end and into the hollow interior; and    a solvent based adhesive bonding the connector to the heat shrunk tube.    
     
     
         3 . A medication infusion set in accordance with  claim 1 , further comprising: 
 a soft cannula having a proximal end, a distal end, and a lumen extending between the proximal end and distal ends, the soft cannula proximal end in fluid communication with the base tube distal end.    
     
     
         4 . A medication infusion set in accordance with  claim 1 , wherein the heat shrinkable material is selected from the group consisting of PVC, polyester, and PTFE.  
     
     
         5 . A medication infusion set in accordance with  claim 1 , further comprising at least one filament between the heat shrunk tube and the base tube and extending along the base tube.  
     
     
         6 . A medication infusion set in accordance with  claim 1 , wherein the base tube has a triangular cross-sectional shape.  
     
     
         7 . An infusion device comprising: 
 a housing including a proximal end, a distal end, two lateral sides, and a bore extending between the proximal end and the distal end;    a soft cannula having a proximal end, a distal end, and a lumen extending between the proximal end and the distal end, the cannula positioned in part in the housing bore with the cannula distal end outside of the housing;    a locking device attached to a lateral side of the housing, the locking device including a locking finger and a lever, the lever extending distally and the locking finger extending proximally, the locking finger including a distally facing surface.    
     
     
         8 . An infusion device in accordance with  claim 7 , wherein the housing bore includes a proximal opening, and further comprising a dust door positioned adjacent to the bore proximal opening, the dust door formed of a resilient and flexible material, the dust door including a planar sheet having at least one slit through the sheet to form at least two flaps.  
     
     
         9 . An infusion device in accordance with  claim 7 , wherein the soft cannula lumen has a first inner diameter and a second smaller inner diameter, the second inner diameter being in a region adjacent the cannula proximal end.  
     
     
         10 . An infusion device in accordance with  claim 7 , wherein the soft cannula further comprises an exterior surface and a bead extending from the exterior surface between the proximal and distal ends.  
     
     
         11 . A connecting device comprising: 
 a hub including a proximal end face, a distal end face, two lateral sides, and a bore extending between the proximal end and the distal end;    a rigid cannula including a proximal end, a distal end, and a lumen extending between the proximal end and the distal end, the rigid cannula mounted in the hub bore with the rigid cannula distal end exterior of the hub;    a pin extending distally from the hub distal end face and offset laterally from the rigid cannula;    a proximally facing surface on one of the lateral sides positioned between the proximal end face and the distal end face.    
     
     
         12 . A connecting device in accordance with  claim 11 , further comprising a length of tubing having a proximal end, a distal end, and a lumen extending between the proximal end and the distal end, the tubing distal end positioned in the hub bore and in fluid communication with the rigid cannula lumen.  
     
     
         13 . A connecting device in accordance with  claim 11 , wherein the pin is a first pin, and further comprising a second pin extending distally from the hub distal end face and offset laterally from the rigid cannula and from the first pin.  
     
     
         14 . A process of forming a medical infusion set, comprising the steps of: 
 inserting an end of a rigid cannula into the lumen of a length of tubing;    heat shrinking a tube of heat shrinkable material over the portion of the tubing in which the end of the rigid cannula is positioned to compress the tubing onto the rigid cannula.    
     
     
         15 . A process in accordance with  claim 14 , wherein the tubing is formed of a material selected from the group consisting of polyethylene and polypropylene.  
     
     
         16 . A process in accordance with  claim 14 , wherein the heat shrinkable material is selected from the group consisting of PVC, polyester, and PTFE.  
     
     
         17 . A process in accordance with  claim 14 , further comprising: 
 solvent bonding a connector to the heat shrunk tube, the connector including a collar through which the another end of the rigid cannula extends.