Abstract:
Ergonomic syringe systems provide attachments that may be used to allow users to dispense or draw in fluid with increased operator comfort and reduced risk of repetitive strain injuries. The disclosure describes supports for holding syringes that permit one-handed operation, handles that are removably attachable to syringe plungers and hand supports that are removably attachable to syringe barrels.

Description:
REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims priority from U.S. application No. 61/488,258, filed 20 May 2011, and entitled ERGONOMIC SYRINGE ADAPTER and U.S. application No. 61/536,643 filed 20 Sep. 2011 and entitled ERGONOMIC SYRINGE ADAPTER both of which are hereby incorporated herein by reference for all purposes. For purposes of the United States of America, this application claims the benefit under 35 U.S.C. §119 of U.S. application No. 61/488,258, filed 20 May 2011, and entitled ERGONOMIC SYRINGE ADAPTER and U.S. application No. 61/536,643 filed 20 Sep. 2011 and entitled ERGONOMIC SYRINGE ADAPTER both of which are hereby incorporated herein by reference for all purposes. 
     
    
     TECHNICAL FIELD 
       [0002]    This invention relates to syringes. Specific embodiments provide apparatus for facilitating operation of syringes. An example embodiment provides a chemotherapy treatment chair having an arm rest and a syringe holder positioned to support a syringe while a medical professional operates the syringe to inject chemotherapy drugs into a patient. Other embodiments provide grips/adapters that may be mounted to the barrel and/or plunger of a syringe to provide a more ergonomic way to use the syringe. 
       BACKGROUND 
       [0003]      FIG. 1  shows a typical prior art syringe  10 . Syringe  10  comprises a body or barrel  12  and a plunger  14 . A sealing piston  15  is engaged in a bore of barrel  12  so that advancing the plunger  14  toward a tip  16  of the syringe causes ejection of fluids from the syringe through an opening  17  on the distal end of the syringe. Syringe  10  may comprise a fitting, for example, a Luer lock fitting or any other suitable fitting for coupling syringe  10  to a needle, tube or other conduit for carrying the fluid expelled from syringe  10 . 
         [0004]    Syringes like syringe  10  are designed to be held in one hand by a user who presses their thumb on a pad  19  on the end of plunger  14  and who holds tabs  20  which project on either side of barrel  12  with the first and second fingers of the hand holding the syringe. The user can then advance the plunger by pressing with their thumb. The user can monitor the progress of the injection (e.g. determine how much fluid has been injected) with reference to graduations or other indicia  18  on barrel  12 . Barrel  12  is typically made of a translucent or transparent plastic, glass, or other suitable material such that the position of piston  15  can be viewed through all or a portion of barrel  12 .  FIG. 1A  shows a syringe being used in a conventional manner to inject fluids into a patient. 
         [0005]    Some patients are treated for cancer using periodic injections of chemotherapy drugs. The chemotherapy drugs are typically injected by a medical professional who monitors to ensure that the injection is going well. In many cases chemotherapy requires injections of relatively large volumes of drugs. Some such chemotherapy drugs are toxic and/or corrosive. It can be important not to inject the drugs too quickly into the patient. As a result of the above, medical personnel who inject chemotherapy drugs may spend a significant portion of each day holding relatively heavy syringes while maintaining constant thumb pressure to inject chemotherapy drugs at an appropriate rate into the patients they are helping to treat. This can result in repetitive strain injuries or other injuries to the health care providers. 
         [0006]    The inventors have conducted an ergonomic assessment of the task performed by chemotherapy nurses. This assessment revealed that administration of chemotherapy drugs via syringe (20 ml or greater size) results in a significant risk for injury to the hands/fingers, wrist, forearm and elbow of the chemotherapy nurses. This is likely due to prolonged hand grip force combined with awkward hand/finger postures. Extended use of syringes can result in significant injury to operators of syringes in other fields as well. 
         [0007]    Another group of professionals who make extensive use of syringes are pharmacy personnel who may be charged with loading multiple syringes with drugs. Pharmacy personnel have reported injuries of the wrist, hand, elbow (medial and lateral sides), and shoulder. These injuries may result in symptoms such as pain, tenderness, stiffness, tingling, and muscle spasms. Many pharmacy personnel experience pain or discomfort in one or more of the following areas: hand, wrist, forearm, elbow, shoulder. This pain or discomfort is often related to the actions of withdrawing solutions (pulling plunger of syringe) and injecting solutions (depressing plunger of syringe). 
         [0008]    Risk factors for injuries related to the repetitive use of syringes include: repetitive and forceful gripping combined with awkward hand and wrist postures when pre-filling syringes; awkward and static shoulder posture when holding vials during the syringe pre-filling procedures; and awkward and repetitive hand and wrist postures combined with forceful gripping when injecting solutions into saline-filled IV bags. 
         [0009]    Patents and applications relating to syringes and attachments for syringes include the following:
   US 2012/0041388;   US 2011/0137260;   US 2011/0092952;   US 2009/0093787;   US 2007/0052409;   US 2004/0039345;   U.S. Pat. No. 7,118,556;   U.S. Pat. No. 6,616,634;   U.S. Pat. No. 6,368,308;   U.S. Pat. No. 6,312,410;   U.S. Pat. No. 5,584,814; and,   U.S. Pat. No. 5,554,132.   
 
         [0022]    There remains a need for methods and apparatus which can alleviate the risk of injury from prolonged use of syringes. There is a particular need for such apparatus and methods that can be implemented at relatively low cost. 
       SUMMARY 
       [0023]    This invention has a range of aspects that may be used together in various combinations or independently. One aspect provides supports for supporting syringes in use. The supports may facilitate one-handed operation of supported syringes and may be adjustable for operator comfort and safety. Another aspect provides attachment handles that may be affixed to a syringe plunger to facilitate safe and comfortable operation of the syringe. Another aspect provides grips that are affixable to the barrels of syringes to facilitate safe and comfortable operation of the syringe. 
         [0024]    One aspect provides an apparatus for supporting a syringe. The apparatus comprises a base configured for mounting to a support, a coupling configured for removable attachment to a proximal end of a plunger of the syringe; and, an arm connecting the coupling to the base. A user can operate the syringe with one hand by moving a barrel of the syringe relative to the base. The base may be a attachable to a table, tray, arm, or the like or may be incorporated into a piece of furniture. In an example embodiment the apparatus comprises a patient chair comprising a seat for a patient to sit in and an arm rest mounted adjacent to the seat wherein the base is attached to the arm rest. 
         [0025]    In some embodiments the coupler comprises a T-slot arranged to receive a pad at the proximal end of the plunger. The arms of the T-slot may have a dimension about equal to a thickness of the pad such that the pad is a reasonably snug fit into the T-slot. 
         [0026]    The coupler may comprise a retainer member having a first position wherein the retainer member projects to block removal of the pad from the T-slot and a second position wherein the retainer member does not block removal of the pad from the T-slot. A transverse dimension of the T-slot and a longitudinal dimension between the retainer member and a closed end of the T-slot may be substantially equal to facilitate good support of a syringe wherein the pad is circular or generally circular (for example, square with rounded corners). 
         [0027]    The apparatus optionally but preferably comprises a hand support shaped to provide a passage for receiving a barrel of the syringe. The hand support may be resiliently compressible. In an example embodiment, the hand support has a smaller-diameter end and a larger-diameter end and the hand support tapers smoothly toward the smaller-diameter end. The hand support may be mounted to the barrel of a syringe such that the smaller-diameter end faces the tip (distal end) of the syringe barrel. The hand support may be generally circular in cross-section at the smaller-diameter end and flattened at the larger-diameter end. 
         [0028]    In some embodiments the hand support has a major diameter and a minor diameter at the larger-diameter end and a ratio of the major diameter to the minor diameter is approximately 4:3. The major diameter may be, for example, approximately 2 inches (5 cm). In some embodiments, both the major diameter and the minor diameter are at least 1¼ inches (about 3.2 cm). 
         [0029]    Another aspect provides hand supports for use with syringes. The hand supports comprise a body shaped to provide a through-passage for receiving a barrel of the syringe. the body has a smaller-diameter end and a larger-diameter end and the hand support tapers smoothly toward the smaller-diameter end. The body may be resiliently compressible. For example, the body may be made of a foam, memory foam, compressible rubber, or the like. In some embodiments the body is generally circular in cross-section at the smaller-diameter end and is flattened at the larger-diameter end. In some embodiments the body has a major diameter and a minor diameter at the larger-diameter end and a ratio of the major diameter to the minor diameter is approximately 4:3. The major diameter may be, for example, approximately 2 inches (5 cm). In some embodiments both the major diameter and the minor diameter are at least 1¼ inches (about 3.2 cm). 
         [0030]    Another aspect provides an accessory handle for a syringe. The accessory handle comprises a handle connected to a coupling. The coupling is configured to engage a pad at a proximal end of a syringe plunger. The coupling comprises a T-slot and a retainer member having a first position wherein the retainer member projects to block removal of the pad from the T-slot and a second position wherein the retainer member does not block removal of the pad from the T-slot. The handle may have any of a range of designs as described herein. 
         [0031]    Other aspects provide the use of apparatus as described herein in injecting chemotherapy or other drugs and methods for injecting and/or transferring fluids using syringe accessories as described herein. 
         [0032]    Further aspects and example embodiments are illustrated in the accompanying drawings and/or described in the following description. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0033]    The accompanying drawings illustrate non-limiting example embodiments of the invention. 
           [0034]      FIG. 1  shows a conventional syringe. 
           [0035]      FIG. 1A  shows a syringe being used to inject fluids into a patient. 
           [0036]      FIG. 2  is a side view of a syringe support according to an example embodiment. 
           [0037]      FIG. 3  is a side view of a syringe support according to another example embodiment. 
           [0038]      FIG. 3A  is a perspective view of a hand support. 
           [0039]      FIG. 3B  is an end view of the hand support of  FIG. 3A . 
           [0040]      FIG. 3C  illustrates a support like that shown in  FIG. 3  being used to inject fluids into a patient. 
           [0041]      FIG. 4  is an enlarged perspective view of a coupling for connecting a syringe plunger to a syringe support. 
           [0042]      FIG. 4A  is a cross sectional view of the coupling of  FIG. 4 . 
           [0043]      FIG. 5  is a partially cut-away side view of a syringe mounted to apparatus comprising an extension arm. 
           [0044]      FIG. 5A  is a side view of the syringe and support apparatus of  FIG. 5  in use. 
           [0045]      FIGS. 6A and 6B  re respectively views showing syringes equipped with a cylindrical handle and a flat handle. 
           [0046]      FIG. 7  is a perspective view of a bulb-like hand adapter that may be affixed removably to a proximal end of a syringe plunger. 
           [0047]      FIGS. 7A and 7B  are cross sectional views of the hand adapter of  FIG. 7 . 
           [0048]      FIG. 7C  illustrates a handle like that shown in  FIG. 7  in use for filling a syringe. 
           [0049]      FIG. 8  is a view showing an alternative hand adapter. 
       
    
    
     DESCRIPTION 
       [0050]    Throughout the following description specific details are set forth in order to provide a more thorough understanding to persons skilled in the art. However, well known elements may not have been shown or described in detail to avoid unnecessarily obscuring the disclosure. The following description of examples of the technology is not intended to be exhaustive or to limit the system to the precise forms of any example embodiment. Accordingly, the description and drawings are to be regarded in an illustrative, rather than a restrictive, sense. 
         [0051]      FIG. 2  is a side elevation view of a syringe  10  being held in a ergonomic syringe support  30  according to an example embodiment of the invention. Support  30  includes a arm  32  coupled between a base  34  and a coupling  36 . Coupling  36  is adapted to receive and hold the proximal end of plunger  14  of syringe  10 . 
         [0052]    As shown in  FIG. 1 , many currently-available syringes  10  have a circular pad  19  at the proximal end of plunger  14 . Coupling  36  may be configured, as described in more detail below, to receive and hold the circular pad  19  at the end of plunger  14  of syringe  10 . In alternative embodiments, coupling  36  may be adapted to engage syringes having a non-standard end for engagement by coupling  36 . For example, syringes for use with apparatus as described herein may be supplied with plungers having proximal ends specifically configured for releasable coupling to a coupling  36 . In such embodiments, the proximal end of the syringe plunger and coupling  36  may be mating parts of any suitable coupling type. Such embodiments may have the disadvantage of not being usable with standard syringes and the advantage that the configuration of the syringe plunge may be selected to discourage use of the syringe except together with support  30  (or a suitable handle coupled to the plunger by way of a coupling  36  as described below). 
         [0053]    As shown in  FIG. 2 , support  30  is adapted to support syringe  10  at a convenient location and orientation above a surface on which base  34  is sitting. For example, the embodiment illustrated in  FIG. 2  shows a case where base  34  is mounted to an arm support tray  38  of a chemotherapy treatment chair (the rest of the chemotherapy treatment chair is not shown). 
         [0054]    In the illustrated embodiment, coupler  36  is connected to arm  32  by way of a pivotal connection  40 . Pivotal connection  40  may be locked at any desired angle to hold syringe  10  at the desired angle. Preferably pivotal connection  40  can at least support syringe  10  in a generally horizontal orientation as shown in  FIG. 2  (e.g. a longitudinal centerline of syringe  10  is parallel to arm support  38 ) and an orientation in which syringe  10  is inclined upwardly (e.g. the distal end of syringe  10  is above the proximal end of syringe  10 ). In an example embodiment, pivotal connection  40  permits the angle of syringe  10  relative to surface  38  to be adjusted in a range of at least 0 degrees (parallel to surface  38 ) to 45 degrees (inclined upward so that the distal end of syringe  10  projects away from surface  38  at an angle of 45 degrees). 
         [0055]    Pivotal connection  40  may be adjusted for the comfort of the person administering drugs using syringe  10 . 
         [0056]    Some embodiments provide a plurality of couplings dimensioned to couple to a plurality of different sizes of syringe plunger. A user may attach a selected one of the couplings to the arm to support a syringe. In some embodiments the pivotal connection  40  comprises two separable parts. One of the separable parts is attached to the arm. Each of the plurality of couplings is attached to a second part of the pivotal connection that can be snapped into place on or otherwise mated to the first part of the arm such that any selected one of the plurality of couplings may be pivotally coupled to the arm at the pivotal connection. 
         [0057]    In the embodiment illustrated in  FIG. 2 , support  30  permits adjustment of the location of syringe  10  in a direction  44 . Syringe  10  may be locked in place at a desired location in direction  44 . In the illustrated embodiment, this adjustability is provided by a clip-track  45  made up of two members  45 A each provided with notches  46  such that pairs of notches  46  are found on either side of a slot within which the proximal end of arm  32  can be received. A pair of pins  47  project to either side of the proximal end of arm  32 . Pins  47  may be received in and engaged with slots  46  to hold arm  32  at a desired position in direction  44 . Clip track  45  is optionally mounted in a manner that permits it to swivel from side-to-side. For example, clip track  45  may be mounted to base  34  by a pin that permits clip track  45  to pivot about a vertical axis. 
         [0058]    The illustrated embodiment includes an additional hand support member  50  that is disposed on the proximal end of the barrel of syringe  10 . Hand support  50  may be compressible. For example, hand support  50  may be made of or have an outer layer of a resiliently-compressible material such as rubber, foam, memory foam, or the like. In other embodiments hand support member  50  is rigid or nearly-rigid. Hand support  50  provides a larger-diameter surface that can be comfortably gripped by a user&#39;s hand while the hand retains a relaxed posture. The outer surface of hand support  50  may optionally be textured and/or coated with a resilient material and/or a high friction material so that it can be securely held by a user with reduced grip force. Hand support  50  may have a diameter large enough that it can be comfortably gripped by a user for extended periods of time. 
         [0059]      FIG. 3  is a side view of a syringe support  30 A that is similar to syringe support  30 . In syringe support  30 A, arm  32  is coupled to base  34  by a pivotal coupling  49  that permits rotation of arm  32  about an axis  49 A. In the illustrated embodiment, axis  49 A is at right angles to axis  40 A of rotation of pivotal coupling  40 . 
         [0060]      FIG. 3A  shows an example construction for hand support member  50 . Hand support  50  includes a central passage  52  that passes over barrel  12  of syringe  10 . Passage  52  may be dimensioned such that hand support member  50  lightly grips barrel  12 . In the illustrated embodiment, hand support  50  is pear-shaped having a bulging proximal end  50 A that tapers down to a thin edge at its distal end  50 B. Hand support  50  may be short enough to leave graduations on barrel  12  exposed so that a person using syringe  10  can monitor the progress of the injection. 
         [0061]    Hand support  50  may optionally have a slit extending into bore  52 . A user can pull the slit open to permit hand support  50  to be placed on a syringe barrel without inserting the distal tip of the syringe through bore  52 . The hand support  50  may be made of a resiliently flexible material which allows edges of the slit to be pulled apart sufficiently to pass over the barrel of a syringe from the side and then closes around the barrel of the syringe. This construction may allow hand support  50  to be more easily mounted to the barrel of a syringe and also permits hand support  50  to be mounted in a way that prevents accidental contact with the distal tip of the syringe. 
         [0062]    Hand support  50  may be made to have a geometry that is not circularly symmetrical with regard to the longitudinal centerline of passage  52 . For example, hand support  50  may be flattened as shown in the end view of  FIG. 3B . In some embodiments a ratio of major and minor diameters of hand support  50  at the large end of hand support  50  is about 4:3. for example, the major diameter may be about 2 inches (5 cm) while the minor diameter is about 1½ inches (3¾ cm). In some embodiments both the major diameter and the minor diameter are at least 1¼ inches (about 3.2 cm). 
         [0063]    In the embodiment illustrated in  FIG. 3 , base  34  is configured to be detachably affixable to a tray  38 . In the illustrated embodiment, base  34  may be slid into engagement with tray  38 . This is achieved by providing a channel  56  which receives an edge  38 A of tray  38 . In the illustrated embodiment, channel  56  has portions that grip tray  38  on either side of a corner of tray  38 . Channel  56  comprises a wall  56 A which extends downward from base  34  substantially perpendicular to base  34  and a flange  56 B extending continuously or intermittently along the lower edge of wall  56 A. 
         [0064]      FIG. 3C  illustrates a support like that shown in  FIG. 3  being used to inject fluids into a patient. 
         [0065]    Many alternative structures may be provided which also come within the scope of the invention. For example, arm  32  may be directly mounted to a tray  38  or the like without a separate base  34 . Base  34  may attached to tray  38  or another surface in many alternative ways. For example, base  34  may be equipped with one or more of: clamps to grab tray  38 ; suction cups to adhere to a surface of tray  38 ; an adhesive for adhesive affixation to tray  38 ; a magnet to hold base  34  to a metal on or in tray  38 ; holes accommodating screws or rivets affixing base  34  to tray  38 ; or the like. Tray  38  may be made to include features for connecting arm  32  directly to tray  38 . A syringe support may be configured for mounting to a table, arm-support tray, arm of a chair, bed rail, or the like. 
         [0066]    Various alternative structures may be provided to permit horizontal displacement of syringe  10  along a tray  38  or other surface. For example, an arm  32  may be coupled to a traveler member that can be slid along a track comprising a T-shaped member, a T-slot, a bar, or the like that is affixed to tray  38 . A clamp, detent mechanism or the like may be provided to lock the traveler at a desired location along the track. 
         [0067]    Details of the configuration of pivotal couplings  40  and  49  may also be varied. For example, one or both of couplings  40  and  49  could be provided by a ball joint. A pivotal coupling may optionally be provided with one or more detents, a locking/clamping mechanism or the like to assist in holding the pivotal coupling at a desired angle. 
         [0068]      FIG. 4  illustrates a possible implementation of coupling  36 . In the illustrated embodiment, coupling  36  comprises a body  60  in which is formed a T-slot  62 . Undercut areas  62 A and  62 B of T-slot  62  are dimensioned to receive corresponding edges of a pad  19  at the proximal end of plunger  14  of a syringe  10  (see  FIG. 1 ). T-slot  62  has an open end  63  into which pad  19  can be slid. The width W of the opening  63 A of T-slot  62  is smaller than that of pad  19 . A syringe may be coupled to coupling  36  by sliding pad  19  into T-slot  62 . 
         [0069]    A catch  64  releaseably locks pad  19  in place in T-slot  62 . Catch  64  may, for example, be resiliently mounted so that it snaps into place after pad  19  has been fully slid into T-slot  62  but can be manipulated to permit pad  19  to be removed. Catch  64  may, for example, comprise a spring, spring-loaded plunger or the like. In some embodiments, distance between catch  64  and a wall  65  at an opposing end of slot  62  is substantially equal to a width of the interior of slot  62  between walls  62 A and  62 B. Catch  64  is not required for all applications. For example, for some applications T-slot  62  may be oriented such that open end  63  faces upward and/or the dimensions of T-slot  62  are such that pad  19  is held securely enough for the application without a catch  64 . 
         [0070]    The dimensions of coupling  36  may be varied to accommodate syringes of different sizes. In some embodiments, coupling  36  is user-detachable from syringe support  30  or  30 A so that a user can replace coupling  36  with a coupling suitable for a syringe to be used. For example, connectors dimensioned to attach to the proximal end of the plungers of syringes having capacities of 20 ml, 30 ml and 60 ml may be provided. 
         [0071]    A user can operate syringe  10  one-handed after syringe  10  has been coupled to support  30 . The user can grasp hand support  50  and pull barrel  12  in the direction of arrow  66  (see  FIG. 2 ) to inject fluid into a patient. The fluid is typically carried into the patient by a short (e.g. 15 cm or 6 inch) section of tubing connected from a fitting of syringe  10  to a needle (not shown) that has been placed in a suitable blood vessel of the patient. 
         [0072]    In administering chemotherapy drugs it is sometimes desirable to withdraw fluid back toward syringe  10  as a check to ensure that the needle is still engaged in the blood vessel of the patient. If the needle is properly engaged in the blood vessel of the patient, then withdrawing fluid toward syringe  10  will bring some blood into the tubing which can be observed by the person administering the chemotherapy drugs. One way to withdraw blood into the tubing is to push the barrel of syringe  10  in direction  67  (in cases where the syringe is injecting fluids into a saline line that is connected to deliver the fluids mixed with saline solution to the patient, another way to withdraw blood into the tubing is to interrupt flow in the saline line—e.g. by pinching the saline line with a free hand). Support  30  advantageously supports much or all of the weight of syringe  10  and any drugs in syringe  10 . In addition, a user who is operating syringe  10  can grip hand grip  50  of syringe  10  with their entire hand and can move body  12  of syringe  10  in directions  66  and/or  67  using large muscle groups in their arms and shoulders. This contrasts with prior art injection techniques in which muscle groups operating the thumb and fingers are directly used both to support and to operate syringe  10 . 
         [0073]    In some embodiments, an extension arm is removably connected to body  12  of syringe  10 . An operator may grasp the extension arm instead of body  12  in order to operate syringe  10 . In some such embodiments the extension arm slides over a pin that couples to a proximal end of the plunger of the syringe.  FIG. 5  shows an example extension arm. In the embodiment of  FIG. 5 , extension arm  70  comprises a tubular member having a bore  72  extending longitudinally through it. A distal end  71  of tubular member  70  is expanded to receive the proximal end of barrel  12  of syringe  10 . Slots  73  are provided to receive flanges  20  of syringe  10 . A retaining member  75  holds extension arm  70  to body  12 . In the illustrated embodiment, distal end  71  of extension arm  70  has female threads while retaining member  75  has male threads. Retainer member  75  has a bore which slips over the body  12  so that retaining member  75  can be releasably affixed to extension arm  70  thereby holding body  12  in place on the end of extension arm  70 . 
         [0074]    In the illustrated embodiment, extension arm  70  is designed to be used with a pin  78  that is in turn supported by a suitable support (not shown in  FIG. 5 ). A support of the general type shown in  FIG. 2  or  3  could, for example, be used to support pin  78  with modifications to hold pin  78 . 
         [0075]    Pin  78  is dimensioned to permit it to pass through bore  72  of extension arm  70 . A coupler  77  is provided on the distal end of pin  78  for coupling to a proximal end of a syringe plunger. In the illustrated embodiment, coupler  77  comprises a pair of fingers  77 A which can engage pad  19  of a plunger  14 . Pad  19  is held in place by coupler  77  as long as it is within bore  72  of extension arm  77 . 
         [0076]    The outer surface of extension arm  70  may be textured and/or coated with a resilient material and/or a high friction material so that it can be readily gripped by a user. Extension arm  70  may have a diameter large enough that it can be comfortably gripped by a user for extended periods of time. A hand support like hand support  50  may optionally be provided on or integrated into extension arm  70 . 
         [0077]    To attach a syringe  10  to a coupler and extension arm according to this embodiment, pad  19  of the syringe can be slid radially under projecting fingers  77 A and extension arm  70  can then be slid along pin  78  until pad  19  and fingers  77 A are received within the bore  72  of extension arm  70 , thereby preventing removal of pad  19 . Retaining member  75  can then be slipped over the end of barrel  12  of syringe  10  and engaged with the threads on distal end  71  of extension arm  70 . A user can then operate syringe  10  by sliding extension arm  70  back and forth as indicated by arrow  79  in  FIG. 5A . This embodiment can leave the entire length barrel  12  of syringe  10  substantially unobstructed and visible throughout a procedure. 
         [0078]    Use of a coupling  36  as illustrated in  FIGS. 4 and 4A  is not limited to attaching the plunger of a syringe to a support arm. Such couplings (and variations on such couplings) may also be used to attach a variety of useful handles onto standard syringes. Some such handles can facilitate the safe repeated use of syringes. Examples of handles that may be attached to syringes using a coupling like coupling  36  are illustrated in  FIGS. 6A ,  6 B and  7 .  FIG. 6A  shows a rod-like handle adapter  90 A. The handle may be cylindrical or have other configurations. For example, the handle may be oval or otherwise flattened in cross-section.  FIG. 6B  shows an enlarged flat handle adapter  90 B which is circular in the illustrated embodiment but could have other shapes as well. Handle adapter  90 B provides a generally flat surface  92  oriented generally perpendicularly to the axis of a syringe plunger  14  on which it is mounted. A user can operate a syringe equipped with handle adapter  90 B by, for example, pressing handle adapter  90 B against their body. A user may apply a pulling force by grasping a recessed handle  91  provided in handle adapter  90 B. 
         [0079]      FIG. 7  shows a bulb-like hand adapter  100  that may be affixed removably to a proximal end of a syringe plunger. Hand adapter  100  may, for example, be used in a pharmacy setting by a person who needs to repeatedly fill syringes with drugs or other fluids and/or transfer fluids using syringes. A hand adapter  100  has dimensions which allows it to be comfortably gripped in the palm of a user&#39;s hand, thereby avoiding the need for the user to exert all of the force needed to drive a syringe plunger with his or her thumb. Hand adapter  100  permits a user to maintain his or her hand and wrist in a neutral posture and also to distribute forces evenly over the entire hand of the user during the operations of filling a syringe and/or dispensing fluid from the syringe. 
         [0080]    In some embodiments a proximal end of hand adapter  100  is flat or has feet such that hand adapter  100  can be placed to stand upright on a flat surface with an attached syringe oriented generally vertically. This is useful, for example in the case where a technician fills syringes with medications and a pharmacist checks the doses in the syringes. A technician may fill one or more syringes and then place each syringe in a vertical position standing on the proximal end of hand adapter  100 . For example, the syringes may stand on a counter in a fume hood. With the syringes standing upright it is easy for the pharmacist to check the accuracy of the dosage in each syringe. 
         [0081]    As shown in  FIG. 7B , hand adapter  100  may be non-circular in cross section in a portion near its proximal end (the end away from coupler  36 ). In the illustrated embodiment, hand adapter  100  is circular or nearly so in its portion near coupler  36  and the cross sectional profile of hand adapter  100  becomes flattened as one moves away from coupler  36 . In some embodiments a ratio of major and minor diameters of hand adapter  100  at its widest point is about 4:3. For example, the major diameter may be about 2 inches (5 cm) while the minor diameter is about 1½ inches (3¾ cm). In some embodiments both the major diameter and the minor diameter are at least 1¼ inches (about 3.2 cm). The outer surface of hand adapter  100  may be textured and/or coated with a resilient material and/or a high friction material so that it can be securely held by a user with reduced grip force. Hand adapter  100  may have a diameter large enough that it can be comfortably gripped by a user for extended periods of time. 
         [0082]      FIG. 7C  shows a hand adapter attached to the plunger of a syringe being filled with fluid from a vial. It can be seen that the hand adapter allows a user to hold the syringe plunger securely without requiring a tight or awkward grip. 
         [0083]    Hand adapter  100  may be used on its own or in combination with a hand support member  50  or another ergonomic attachment to the barrel of a syringe that facilitates holding the barrel of the syringe by a user. 
         [0084]    An example ergonomic adapter  110  which can be mounted to provide a more comfortable grip on the barrel of a syringe is illustrated in  FIG. 8 . Adapter  110  comprises a body  112  formed to define a channel  114  dimensioned to receive the barrel  12  of a syringe. Flanges  115  project at either end of body  112 . Flanges  115  permit a user to pull or push on the syringe barrel without having to grip the syringe with significant force. Body  112  increases the effective diameter of the barrel of the syringe to permit a user to comfortably grasp the syringe barrel. Flanges  115  provide surfaces against which a user can apply pressure. The presence of these surfaces avoids the need for the user to grip barrel  12  tightly in order to move it in either direction. 
         [0085]    Partially circumferential slots  116  at at least one end of adapter  110  are provided to receive projections  20  of a syringe  10 . Providing slots  116  at both ends of adapter  110  permits the adapter to be used in either orientation. Channel  114  has a concave configuration which is dimensioned to allow barrel  12  of syringe  10  to be snapped into place within channel  112 . Adapter  110  may be placed on a syringe so that the entire scale on the syringe is visible while adapter  110  is in place. 
         [0086]    Features of the illustrated embodiments may be combined to yield further example embodiments. Although embodiments as described herein include various features and are intended to provide examples of different ways to practice the invention not all such features are essential. Other example embodiments may be provided by omitting features from the described embodiments. 
         [0087]    It can be seen from the above that the invention has various aspects including:
       Syringe supports useful, for example, in administering chemotherapy;   Couplings for connecting handles of a wide variety of types to syringe plungers;   Ergonomic hand supports that can be connected to and/or mounted on the barrel of a syringe to provide improved hand position while facilitating good control over the syringe;   Ergonomic handles that may be coupled to a plunger of a syringe to provide improved hand position while facilitating good control over the syringe; and   Chemotherapy treatment chairs that incorporate syringe supports.
 
These aspects may be applied individually or in any suitable combinations.
       
 
         [0093]    It can be appreciated that at least some embodiments of the invention provide various advantages. For example, some embodiments facilitate delivery of the contents of a syringe with one hand while viewing the graduated measurements on the barrel of the syringe. Some embodiments facilitate delivery of the contents of a syringe with one hand while permitting fluids to be periodically partially drawn back into the syringe barrel. These advantages are useful, for example in the delivery of chemotherapy. 
         [0094]    At least some embodiments of the invention provide for the ergonomic delivery of chemotherapy drugs or other fluids using syringes. Ergonomic syringe adapters and/or supports may be applied for dispensing any fluids from standard syringes. Such syringe adapters may help to avoid or alleviate operator pain, discomfort, long term injury and/or disability. Use of such adapters may reduce the risk of repetitive strain injury or other injuries to the health care provider. While the examples given above are in the field of health care, syringe systems as described herein may have application in other fields such as dispensing adhesives, lubricants or other industrial fluids from syringes. 
         [0095]    In some embodiments some or all components described herein are intended to be disposable. Such components may be sterilized and provided in sealed pouches. The components may, for example, be made of plastic. In alternative embodiments some or all components of the embodiments described herein are made of metal or other reusable materials. 
         [0096]    Some embodiments provide syringe supports that are adjustable to permit support of a syringe in a wide range of positions and orientations. Other simpler embodiments may support a syringe at a fixed location. In example embodiments one or more of the following are adjustable:
       the vertical orientation of the syringe relative to a base, other mounting surface or the horizontal (e.g. the syringe may be held horizontally, inclined upwardly or inclined downwardly);   the direction that the syringe is pointing (e.g. the syringe may be pivoted about a vertical or generally vertical axis);   the position at which the syringe is supported (e.g. the syringe may be moved back and forth by adjustment along a horizontal track and/or swung back and forth to a desired position about a vertical axis and/or a mounting point for a syringe support may be adjustable in two dimensions); and   the height of the syringe above a support surface.
 
Not all embodiments provide all of these adjustments. As noted above, in some embodiments the position of the syringe is non-adjustable.
       
 
         [0101]    Other embodiments of the invention permit a wide variety of handles to be attached to standard syringes. In some embodiments a plurality of handles are provided as a kit. The kit may comprise couplers dimensioned to couple to the proximal ends of the plungers of various sizes of syringe. The handles may, for example, include cylindrical handles, D-handles, large-area flat handles, and the like. The handles may comprise handles of the type illustrated in  FIG. 7  for example. 
         [0102]    While it is considered advantageous that the ergonomic accessories described herein may be used together with standard syringes of the type that are commonly available and used, it is also possible to make syringes which are built to incorporate such ergonomic accessories. 
       INTERPRETATION OF TERMS 
       [0103]    Unless the context clearly requires otherwise, throughout the description and the claims:
       “comprise,” “comprising,” and the like are to be construed in an inclusive sense, as opposed to an exclusive or exhaustive sense; that is to say, in the sense of “including, but not limited to”.   “connected,” “coupled,” or any variant thereof, means any connection or coupling, either direct or indirect, between two or more elements; the coupling or connection between the elements can be physical, logical, or a combination thereof.   “herein,” “above,” “below,” and words of similar import, when used to describe this specification shall refer to this specification as a whole and not to any particular portions of this specification.   “or,” in reference to a list of two or more items, covers all of the following interpretations of the word: any of the items in the list, all of the items in the list, and any combination of the items in the list.   the singular forms “a”, “an” and “the” also include the meaning of any appropriate plural forms.       
 
         [0109]    Words that indicate directions such as “vertical”, “transverse”, “horizontal”, “upward”, “downward”, “forward”, “backward”, “inward”, “outward”, “vertical”, “transverse”, “left”, “right”, “front”, “back”, “top”, “bottom”, “below”, “above”, “under”, and the like, used in this description and any accompanying claims (where present), depend on the specific orientation of the apparatus described and illustrated. The subject matter described herein may assume various alternative orientations. Accordingly, these directional terms are not strictly defined and should not be interpreted narrowly. 
         [0110]    Specific examples of systems, methods and apparatus have been described herein for purposes of illustration. These are only examples. The technology provided herein can be applied to systems other than the example systems described above. Many alterations, modifications, additions, omissions and permutations are possible within the practice of this invention. This invention includes variations on described embodiments that would be apparent to the skilled addressee, including variations obtained by: replacing features, elements and/or acts with equivalent features, elements and/or acts; mixing and matching of features, elements and/or acts from different embodiments; combining features, elements and/or acts from embodiments as described herein with features, elements and/or acts of other technology; and/or omitting combining features, elements and/or acts from described embodiments. 
         [0111]    Where a component (e.g. a handle, rod, plunger, coupling, base, chair, etc.) is referred to above, unless otherwise indicated, reference to that component (including a reference to a “means”) should be interpreted as including as equivalents of that component any component which performs the function of the described component (i.e., that is functionally equivalent), including components which are not structurally equivalent to the disclosed structure which performs the function in the illustrated exemplary embodiments of the invention. 
         [0112]    It is therefore intended that the following appended claims and claims hereafter introduced are interpreted to include all such modifications, permutations, additions, omissions and sub-combinations as may reasonably be inferred. The scope of the claims should not be limited by the preferred embodiments set forth in the examples, but should be given the broadest interpretation consistent with the description as a whole.