Patent Publication Number: US-11648344-B2

Title: Infusion set improvements

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. application Ser. No. 15/619,912, filed Jun. 12, 2017, which is a continuation of U.S. application Ser. No. 14/822,539, filed Aug. 10, 2015, now U.S. Pat. No. 9,675,750, which is a continuation of U.S. application Ser. No. 13/959,102, filed Aug. 5, 2013, now U.S. Pat. No. 9,101,704, which is a continuation of Ser. No. 11/235,843, filed on Sep. 27, 2005, now U.S. Pat. No. 8,500,054, which claims priority to U.S. Provisional Application Ser. No. 60/613,556 filed on Sep. 27, 2004, each of which is incorporated herein by reference in its entirety. 
    
    
     TECHNICAL FIELD 
     The present invention relates to methods and objects directed to improving the use of infusion sets to deliver fluids to a patient, for example the delivery of insulin to a patient suffering from diabetes. More particularly, the invention relates to methods and objects of adjusting the length of tubing used in an infusion set. 
     BACKGROUND ART 
     Infusion sets are typically used to transfer fluids from a source to a patient. An infusion set typically includes a cannula assembly that may be made up of a cannula which is inserted into a patient with the use of a needle, and a cannula body which is used to hold the upstream end of the cannula. The needle is typically removed before fluid may be transferred through the cannula. The cannula body may be used to secure the cannula to a patient&#39;s body in a specific position. The cannula is attached to a tube, usually a flexible tube, which conducts fluid from a source to be transferred to the body. 
     Infusion sets may present a number of user-oriented, operational problems due to the competing interests of providing a device capable of being used by many, while being tailored to an individual&#39;s needs. 
     In one aspect of infusion sets, the length of a tube used in an infusion set must be able to reach a distance between the insertion site of the cannula and the source of the infused fluid. The tubes are typically flexible, allowing for convenience in handling by users. In the instance when a source is a portable source that may be worn by a patient, the length of tube necessary depends upon the relative positions of the source and the insertion site, which may be a function of the size of the patient. As well, patients may wish to alter the position where they wear the source and/or the insertion site depending upon individual circumstances. Tube suppliers manufacture various lengths of tubes. However, requiring patients to purchase various lengths of tubing depending upon their needs, and requiring suppliers to stock every length of tubing desired may be impractical. Patients who use tubes that are too long may insure that an adequate length is available, but risk entangling the excess tube in stray objects or potentially dislodging the 
     cannula assembly or fluid source if the excess tubing snags. 
     In general, a need exists to improve the design of infusion sets to address this problem. 
     SUMMARY OF THE INVENTION 
     Embodiments of the invention utilizing a tube length adjuster may be directed toward adjusting an unstored length of a tube used to carry fluids from a source to a patient. The adjuster may be capable of storing a portion of tubing within its structure, and leaving an unstored length of exposed tubing. Thus, the effective length of tubing connecting a source and an insertion point, using some embodiments of the invention, is approximately the length of unstored tubing plus some length defined by the physical dimension of the adjuster. The adjuster may allow a user to adjust the length of unstored tubing depending upon the needs of the user. 
     A tube length adjuster, according to embodiments of the invention, includes a storage module for storing a portion of excess tubing length, relative to the desired effective tube length. Such an adjuster may be utilized in a method of adjusting an unstored length of tubing used to transfer fluid to a living body according to another embodiment of the invention. The method includes the steps of providing an adjuster; providing a tube for transferring at least some fluid; removably attaching the tube to the adjuster; and storing a portion of the tube on the storage module to adjust the unstored length of tube. Alternatively, the method may include the step of fixing the unstored length of the tube. 
     In accordance with embodiments of the invention an adjuster is provided for adjusting the unstored length of tubing used to transfer at least some fluids from a source to a user. Preferably, the user wraps the unstored tubing around the storage module until the user achieves the desired length. Additionally, the adjuster may include features to maintain the length of stored tubing around the adjuster and/or enable the secure attachment or placement of the adjuster. 
     In accordance with other embodiments of the present invention, a user may attach the tubing to the adjuster and rotates, winds, spins or stores the tubing inside the storage module. 
     The user may then fix the length of the unstored tubing by securing the tubing and/or closing the unstorage module. Furthermore, the storage module may have friction structures incorporated into the housing to secure the tubing. To unsecure the tubing the user disengages the tubing from the friction structure. 
     In accordance with yet other embodiments of the invention, the tubing may be retractably guided into the storage module. Similarly, the user may fix the length of the unstored tubing by securing the tubing, engaging a friction structure, or closing the storage module. When a different length of tubing is required, a tug on the tubing can retract the tubing from the storage module. 
     Some embodiments of the invention are directed toward improvements in the use of infusion sets for injecting fluids into patients. Such infusion sets are typically designed for injecting fluids into human beings, but can also be utilized in conjunction with other mammals, animals, and other living beings. The embodiments of the invention directed to adjusting the unstored length of a tube are not restricted to tubing of a particular length or diameter. In addition, the embodiments of the invention are not necessarily restricted to uses of adjusting the length of tubing used to transfer fluids to patients. Some embodiments of the invention may be utilized in other applications in which adjusting the length of flexible tubing is advantageous. 
     As is readily apparent to those skilled in the art, a variety of different arrangements of different structures, including arrangements not mentioned herein, may be utilized to create adjusters capable of being used with the method described above. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The foregoing features of the invention will be more readily understood by reference to the following detailed description, taken with reference to the accompanying drawings, in which: 
         FIG.  1 A  schematically shows a tube length adjuster, in accordance with an embodiment of the present invention; 
         FIG.  1 B  schematically shows a tube length adjuster having a fastener, in accordance with an embodiment of the invention; 
         FIG.  1 C  schematically shows the tube length adjuster of  FIG.  1 B  with the fastener wrapped around the tubing; 
         FIGS.  2 A- 2 D  illustrate a sequence of attaching tubing to a tube length adjuster, in accordance with an embodiment of the present invention; 
         FIGS.  3 A- 3 B  schematically show a tube length adjuster having a case that opens, in accordance with an embodiment of the present invention; 
         FIG.  4 A  schematically shows an exploded side of a tube length adjuster, in accordance with an embodiment of the present invention; 
         FIG.  4 B  schematically shows a top view of the tube length adjuster shown in  FIG.  4 A ; 
         FIG.  5 A  schematically shows a top view of a tube length adjuster having a rotatable wheel, in accordance with an embodiment of the present invention; 
         FIG.  5 B  schematically shows a top view of the tube length adjuster shown in  FIG.  5 A , in accordance with an embodiment of the present invention; 
         FIG.  5 C  schematically shows an isometric view of the tube length adjuster shown in  FIG.  5 A , in accordance with an embodiment of the present invention; 
         FIGS.  6 A- 6 F  illustrate a sequence of attaching tubing to a tube length adjuster for storage, in accordance with an embodiment of the present invention; 
         FIG.  7 A- 7 D  show an exploded view and the mechanism of a tube length adjuster having a variable internal path for holding tubing, in accordance with an embodiment of the present invention; 
         FIGS.  8 A and  8 B  schematically show a tube length adjuster with variable internal length, in accordance with an embodiment of the present invention; 
         FIGS.  9 A- 9 C  schematically show a tube length adjuster having tracks of sliders configured to move in a circular path, in accordance with an embodiment of the present invention; 
         FIGS.  10 A- 10 C  schematically show a tube length adjuster with a variable internal path, in accordance with an embodiment of the present invention; and 
         FIGS.  11 A- 11 C  schematically show a tube length adjuster having a rotatable shaft and handle, in accordance with an embodiment of the present invention in use. 
     
    
    
     DETAILED DESCRIPTION OF SPECIFIC EMBODIMENTS 
       FIGS.  1 A- 1 C  show various embodiments of a tube length adjuster, all of which are in accord with embodiments of the invention. The adjuster  500  includes a storage module  510  for storing excess tube length by wrapping the tube  530  around the module  510 , and a fastening device such as friction structures  521 ,  522  for maintaining the length of stored tubing around the adjuster  500 . Using the embodiment shown in FIG. IA, the tubing  530  is removably attached to the adjuster using one of the friction structures  521 ,  522 , and the length of unstored tubing is fixed by attaching the tube  530  to the unused friction structure after a portion of tubing  530  is wrapped around the module  510 . In another embodiment of the invention, a fastening device such as a fastener  521 A may be attached to the module  510  as shown in FIG. IB. The fastener  521 A may be wrapped around the tubing stored around the module  510 , to fix the length of the unstored tubing as shown in  FIG.  1 C . The fastener  521 A may be molded as part of the module  510  to form a unitary unit or separately attached to the module after manufacturing the module. When the adjuster with the fastener is molded as a unitary structure, preferably, the fastener is overmolded after the module is molded. Although two examples of fastening devices are shown, a person of skill in the art will recognize that other fastening devices may be used. Such fasteners, although not shown, are within the scope of the invention. 
     Other types of tube length adjusters may be used in conjunction with the method. Some examples of such adjusters are shown in  FIGS.  2 - 4   , all of which are in accord with embodiments of the invention.  FIGS.  2 A- 2 D  depict an adjuster  600  with a storage module including an inner hub sandwiched between two halves  611 ,  612 . One half has a pair of notches  620  for removably attaching tubing  630 . Thus a method of adjusting the length of tubing includes the steps of: removably attaching the tubing  630  in one of the notches  620  (as shown in  FIG.  2 A ); storing the tubing  630  by wrapping the tubing  630  around the hub and between the halves  611 ,  612  to adjust the unstored tubing to a desired length (as shown in  FIGS.  2 B and  2 C ); and fixing the length of the unstored tubing by attaching the tubing  630  in the remaining open notch  620  (as shown in  FIG.  2 D ). 
       FIGS.  3 A and  3 B  depict another adjuster in accord with the invention. As shown in  FIG.  3 A , the adjuster includes at least a pair of hubs  713  which are exposed when the adjuster is opened by lifting open a first half  711  of a case of the adjuster from the second half  712 . The halves  711 ,  712  may optionally be attached by a hinge-like structure as shown in  FIG.  3 A . The hinge-like structure may be any shape. Tubing  730  may be stored by the adjuster by wrapping the tubing  730  about at least a hub  713  to adjust the unstored length. Preferably, the adjuster has a pair of hubs  713  for adjusting the length of the unstored tubing. The first half  711  may be attached to the second half  712  after the wrapping is complete to fix the length of the unstored tubing, as shown in  FIG.  3 B . As shown in  FIGS.  3 A and  3 B , a pair of openings  729  may be included in the adjuster. 
       FIGS.  4 A and  4 B  depict another embodiment of the present invention that may be used to adjust the length of unstored tubing.  FIG.  4 A  shows an exploded view of an adjuster  800 , which includes the elements of a bottom half,  815  with a circular hub  816  and a friction notch  821  to thread one end of the tube; a top half  810  with a notch-opening  822  for threading the tube out of the adjuster  800 , and a cap  840  for locking the positions of the two halves  810 ,  815  in place. With the two halves  810 ,  815  separated, the tube may be attached to the bottom notch  821  to removably attach the tube to the adjuster  800 . Next, a portion of the tube may be stored by wrapping the tube around the hub  816  to adjust the length of unstored tubing. The top half  810  may then be placed over the bottom half  815 , with the loose end of tube threaded through the notch-opening  822 . Finally, the cap  840  may be used to lock the halves in place, as shown in  FIG.  4 B , thus fixing the length of the unstored tubing. An alternative way of adjusting the unstored length of tubing is by rotating the first half  810  while keeping the second half  815  relatively stationary. As described above, the user can thread the tubing through the notch-opening  822  and place the cap  840  to secure it in place, when the desired length is reached. 
       FIGS.  5  and  6    show two other embodiments of adjusters, which may be used to practice the method of adjusting an unstored length of tubing.  FIG.  5 C  depicts a rotatable wheel  910  attached to a body  940 , the rotatable wheel  910  acting as the storage module and having a hub  911 . As shown in  FIG.  5 A , the rotatable wheel  910  includes a notch  920  that may act as a entry point for tubing  930  into the adjuster; the notch  920  may also serve to removably attach the tubing  930 . The wheel  910  may be rotated to store tubing  930  by wrapping the tubing  930  around the hub  911 , and adjusting a length of unwrapped tubing, as shown in  FIG.  5 B . Rotation of the wheel  910  may be achieved by a handle coupled to the wheel  910  through the body  940  to allow easy rotation by hand. Alternatively, the wheel  910  may be rotated by a spring, preferably a torsional spring, with the spring coupled to the wheel  910  such that the wheel  910  tends to rotate and wrap tubing  930  around the hub  911 . When the spring constant of the spring is of sufficient magnitude, the tension in the tubing  930  induced by the spring may be used to fix the length of unstored tubing. The use of a torsional spring may advantageously allow the release of the stored tubing, if an excessive force is applied to the unstored tubing. The release of the stored tubing may relieve the force applied to the unstored tubing. Generally, storing the tubing may also provide additional safety by preventing a cannula assembly from being inadvertently removed from a patient by snagged tubing. Alternatively, a lock mechanism, such as a frictional structure, as described earlier, may be used to fix the length of the unstored tubing in a more secure manner. 
       FIGS.  6 A- 6 F  depict another adjuster with a rotatable member  1010 . The storage module, shown in  FIGS.  6 A- 6 F  is coupled to the rotatable member  1010  and includes a raised hub structure  1020  for removably attaching a tube  1030  by threading the tube  1030  within the hub structure  1020  as shown in  FIG.  6 A . The hub structure may include a plurality of posts. Preferably, the hub structure has at least two posts. Rotation of the member  1010  results in two ends of the tubing  1030  simultaneously being wrapped around the hub structure  1020 , as depicted in  FIGS.  6 B and  6 C . The storage module is enclosed in a case made of two halves  1010 ,  1011 , one half  1010  being the rotatable member coupled to the storage module and the other half with the raised hub structures. The halves  1010 ,  1011  may be separated while the tubing  1030  is removably attached to the hub structure  1020 , and coupled when tube storage occurs, as shown in  FIGS.  6 D and  6 F . Rotation of the rotatable members  1010  or  1011  stores a portion of the tubing by wrapping the tubing around the storage module. Rotation of the member  1010  or  1011  may be performed manually, such as by hand or automatically, by using a spring such as a torsional spring, as described in the description of the embodiment shown in  FIG.  5   . In an embodiment with manual rotation, a handle may be coupled to or molded as part of the rotatable member  1010  or  1011 . The halves  1010 ,  1011  may have at least an opening  1040  for tubing  1030  to enter and exit the casing. Preferably, the halves have a pair of openings as shown in  FIG.  6 B . 
     In another embodiment of the invention shown in  FIGS.  7 - 10   , a tube length adjuster is presented with a variable internal path for holding tubing. An exploded view of one example of such an adjuster is shown in  FIGS.  7 A- 7 D . The adjuster shown in  FIG.  7 A  includes a case and a storage module. The case has two halves  1110 ,  1115 , one half having an opening  1116  for allowing tubing to enter and exit the case. The storage module includes a slider  1120  for moving within two tracks  1122 . The slider includes two rollers  1121  for aiding movement of the slider  1120  and tubing within the case. 
     As shown in  FIG.  7 B , the tubing  1130  is inserted into the case through the opening  1116 , and secured within the case by the slider  1120  and a guide  1117  coupled to the case bottom  1115 . The position of the slider  1120  and guide  1117  define a path for tubing within the case. As shown in  FIG.  7 C , as the slider  1120  is moved along the tracks  1122  in the direction  1150 , the tubing path length within the case changes, allowing for more tubing  1130  to be stored in the case. The rollers  1121  allow tubing  1130  to move in and out of the case, depending upon the position of the slider  1120 , as shown in  FIGS.  7 C and  7 D . Now referring to  FIGS.  7 A and  7 D , the top cover  1110  has a slot  1111  for allowing user access to the slider  1120  to move the slider  1120  within the tracks  1122  as shown in  FIG.  7 D . A locking mechanism may be included to fix the length of tubing taken up within the case. 
       FIGS.  8 A and  8 B  show another example of tube length adjuster with variable internal length. In  FIG.  8 A , an internal view of the adjuster where a plurality of sliders  1220 , each slider  1220  having a track  1221  in the casing, is depicted along with a set of stationary guides  1215 . Although, the housing of the adjuster is depicted as flat, a person of skill in the art would recognize shown in  FIG.  8 A , tubing  1230  may be loaded into the casing, squeezed between the guides  1215  and sliders  1220 . The guides  1215  may include a roller annularly positioned around the guide  1215  to enhance tubing motion around the post  1215 . Likewise, the sliders  1220  may also include an annular roller. The tubing  1230  may be removably attached to the case  1250 . Now referring to  FIG.  8 B , the sliders  1220  may be moved within the their respective tracks  1221 , to alter the internal path and thus length of tubing present within the casing. The sliders  1220  may be moved independently of each other (as shown in  FIG.  8 B ), or be coupled in some manner to move simultaneously. A lock for at least one of the sliders  1220  may also be utilized to fix the length of tubing within the case. 
       FIGS.  9 A- 9 C  depict an adjuster in accord with an embodiment of the invention. The adjuster in  FIGS.  9 A- 9 C  is operational similar to the adjuster in  FIGS.  8 A and  8 B , except that the tracks  1323  of the sliders  1320  in  FIGS.  9 A- 9 C  are configured to move in a circular path, in any direction, as opposed to the straight line path of  FIGS.  8 A and  8 B . As depicted in  FIG.  9 A , tubing  1330  may be mounted between the sliders  1320  and guides  1315  through an opening  1350  in the adjuster. The opening  1350  may also act as a friction structure to allow removable attachment of the tubing  1330  at that location.  FIG.  9 B  depicts the configuration of the tubing  1330  after slider  1321  has been moved clockwise through its track.  FIG.  9 C  depicts the configuration of the tubing  1330  after sliders  1321  and  1322  have been moved clockwise through their tracks. 
       FIGS.  1 OA- 1 OC  depict components of another adjuster with a variable internal path for tubing in accord with an embodiment of the invention. A set of sliders  1421 ,  1422 ,  1423 ,  1424  are arranged in series to travel in a train along a track  1427  as shown in  FIGS.  1 OA and  1 OB . The sliders  1421 , 1422 , 1423 , 1424  may be coupled together such that the movement of one slider induces movement in the other sliders. As shown in  FIG.  10 A , the sliders are flexibly coupled with a flexible tether  1426 . A person skilled in the art will recognize other mechanisms for achieving the coupling. Still referring to FIG. IOA, each slider  1421 ,  1422 ,  1423 ,  1424  may utilize a roller  1425  to aid movement of the tubing along its surface. Now referring to  FIG.  10 B , tubing  1430  may be inserted around one slider  1422  adjacent to an end of the slider train  1421 . As shown in FIG. IOC, the slider at the head of the train  1421  may be moved along a track  1427  in direction  1450  to increase the length of tubing stored within the adjuster. One possible track configuration is a spiral as shown in  FIG.  1 OC . Alternatively, any track configuration may be used to store the tubing. Preferably, the track is configured to provide a compact and efficient storage in the available compartment (As shown in  FIG.  1 OC , the sliders  1421 , 1422 , 1423 ,  1424  may be moved by moving the head slider  1421 , by use of a turnable handle coupled to the slider train, or the use of an elastic member that is biased in a particular direction to attain its equilibrium position. The track  1427  and sliders  1421 ,  1422 ,  1423 ,  1424  may be configured such that tubing  1430  has a tendency to adhere to one side wall  1431  of the adjuster, thus fixing the tube  1430 . The tube  1430  may be released from the adjuster by either pulling on the free end of the tubing or moving the opposite end of the slider train  1424  in the opposite direction of  1450 , to free tubing. 
     As documented by the examples shown in  FIGS.  7 - 10   , one skilled in the art will readily recognize that embodiments of the invention may utilize any number of sliders, designed to travel in any number of tracks in any given orientation in order to create path lengths within a case to adjust the unexposed length of tubing. The guides used in such embodiments of the invention may have a variety of shapes and sizes, and one or more may be utilized with various embodiments. Movement of the sliders may be by user manipulation of individual, or a set of coupled, sliders, use of a mechanical crank coupled to one or more sliders, or the use of an elastic member with a tendency to bias movement of the sliders in a direction to lengthen the variable internal path. In the latter case, the unstored length of tubing is fixed when the tension in the tubing is balanced by the force induced by the elastic member. 
     An alternate embodiment of the invention is shown by the tube length adjuster in  FIGS.  11 A- 11 C . As shown in  FIG.  11 A , the adjuster includes a rotatable shaft  1520  and a handle  1510 . The rotatable shaft  1520  includes a tube guide  1525 , as shown in  FIG.  11 C , which is capable of winding tubing  1530  around the shaft  1520  while it rotates. The handle  1510  includes an opening  1515  for allowing tube  1530  to be threaded out of the handle  1510 , a structure for removably attaching the tube (such as a friction structure), and a hollow region with a spiral notch. The spiral notch has an axis parallel to the axis of the shaft  1520  and is in contact with the rotatable shaft  1520 . By moving the handle  1510  in a direction  1550  parallel to the direction of the axis of the shaft  1520 , the shaft  1520  rotates and tubing  1530  is wound around the shaft and stored. A lock is optionally utilized to lock the handle position and fix the length of tubing not wound around the shaft. In an alternate embodiment, the spiral notch may be ratcheted to allow controlled wind-up of tubing  1530  without a lock mechanism. 
     Although various exemplary embodiments of the invention, and examples thereof, have been disclosed, those skilled in the art will recognize that various changes and modifications can be made which will achieve some of the advantages of the invention without departing from the true scope of the invention. Furthermore, attachment features such as straps including fasteners, velcro, buttons, snaps, clips and other attachment means may be included with the present invention to facilitate the attachment or placement of the present invention on the user.