Abstract:
A connector assembly includes first and second mating connectors that can be joined to make a fluid connection. The connectors are constructed to discriminate improper connectors so that no fluid tight connection can be formed with improper connectors. The connector assembly can be used with a system for compression therapy to prevent deep vein thrombosis. The first connector includes a bleed passage.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is a continuation of U.S. application Ser. No. 11/852,841, filed Sep. 10, 2007, the contents of which are incorporated herein by reference. 
     
    
     TECHNICAL FIELD 
       [0002]    The present disclosure relates to safety connectors for use in medical applications, particularly for use with compression therapy devices. The present disclosure also relates to discriminating safety connector assemblies and, more particularly, to a discriminating safety connector assembly for fluidly coupling at least two lumens capable of forming a non-leaking fluid circuit. 
       BACKGROUND OF THE INVENTION 
       [0003]    In a medical environment, many devices have tubing adapted for manual connection in order to provide a fluid connection between devices or between a device and a patient including enteral feeding pumps and intravenous feeding lines. Each of these devices includes one or more connectors that a user or practitioner may inadvertently connect together. This may result in the successful connection of incompatible devices or the supply of fluid or nutrient to an improper intravenous line or a device such as an inflatable bladder used in deep vein thrombosis therapy. Successful connection of incompatible devices may harm patients or damage equipment. 
         [0004]    When connecting a medical device to a fluid supply, a non-leaking seal must be made between compatible devices and/or fluid sources. Thus, connections must be designed to provide an adequate seal between sealing surfaces when the devices and/or supply are compatible. Typical devices have a male and female connector that, when pressed together, form a fluid tight seal. The connectors come in different sizes and shapes and typically have O-rings or gaskets to help create a fluid tight seal. 
         [0005]    Examples of a medical device connected to a fluid supply include compression therapy devices that are wrapped around a limb to prevent peripheral edema and conditions that form blood clots such as deep vein thrombosis. These devices typically include at least one air bladder that is sized and shaped for being applied around the limb. The bladder is inflated and deflated to artificially stimulate blood flow throughout the appendage that would normally result from, for example, walking. An example of such a device that is configured for disposal about a foot is shown in U.S. Pub. No. 2005/0187499. Typically, these compression devices are connected to a tube set which provides fluid communication from a pressure source to the compression device. A controller is employed to regulate the flow of fluid from the pressure source to the compression device. 
         [0006]    The compression device, tube set and controller each contain connections for connecting and disconnecting the compression device from the pressure source. It is desirable to avoid erroneous connection of a medical device other than the compression device, for example an intravenous needle, to the pressure source. 
       SUMMARY OF THE INVENTION 
       [0007]    In one aspect, a connector assembly for preventing sealing connection with a non-permitted, substantially uniform internal diameter conduit having an end face generally comprises a first connector having a floor and a coupling portion. The coupling portion projects outward from the floor and including a sealing surface and a non-sealing surface located closer to a free end of the first connector than the sealing surface. The non-sealing surface is sized and shaped to hold the non-permitted conduit off of the sealing surface and prevent sealing therewith. A bleed passage in the connector is located generally adjacent the floor for bleeding fluid out of the connector assembly when the non-permitted conduit is attached to the coupling portion. 
         [0008]    In another aspect, a connector assembly for preventing sealing connection with a non-permitted, substantially uniform internal diameter conduit having an end face generally comprises a first connector having a floor and a coupling portion. The coupling portion projects outward from the floor and including a sealing surface and a non-sealing surface located closer to a free end of the first connector than the sealing surface. The non-sealing surface is sized and shaped to hold the non-permitted conduit off of the sealing surface and prevent sealing therewith. A bleed passage is located generally adjacent the floor for bleeding fluid out of the connector assembly. The bleed passage extends through the housing floor. 
         [0009]    Other objects and features will be in part apparent and in part pointed out hereinafter. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0010]    Embodiments of the present disclosure are described herein below with reference to the drawings wherein: 
           [0011]      FIG. 1  is a perspective of a connector assembly with a first and second connector of the connector assembly engaged; 
           [0012]      FIG. 2  is a perspective of the connector assembly with the first and second connector separated; 
           [0013]      FIG. 2A  is a perspective of a “Y” connector releasably attachable to the first or second connector; 
           [0014]      FIG. 3  is a perspective longitudinal section of the connector assembly shown in 
           [0015]      FIG. 1 ; 
           [0016]      FIG. 4  is a perspective of the first connector of the connector assembly shown in  FIG. 1  seen from an end and to a side; 
           [0017]      FIG. 5  is a perspective of the first connector seen substantially from the end; 
           [0018]      FIG. 6  is a perspective of the connector assembly shown in  FIG. 1  having tubing attached; 
           [0019]      FIG. 7  is a perspective of an alternate embodiment of the connector assembly showing two separated connectors with tubing attached; 
           [0020]      FIG. 8  is a perspective longitudinal section of the connector assembly shown in  FIG. 7 ; 
           [0021]      FIG. 9  is a perspective of another alternative embodiment of the connector assembly with tubing attached; 
           [0022]      FIG. 10  is a perspective longitudinal section of the connector assembly as shown in  FIG. 9 ; 
           [0023]      FIG. 11  is a side elevation of another alternative embodiment of the connector assembly with the first and second connectors engaged; 
           [0024]      FIG. 12  is a longitudinal section of the connector assembly shown in  FIG. 11 ; 
           [0025]      FIG. 13  is a perspective of the first connector of the connector assembly shown in  FIG. 11 ; 
           [0026]      FIG. 14  is a perspective of the second connector of the connector assembly shown in  FIG. 11 ; 
           [0027]      FIG. 15  is a side elevation of another alternative embodiment of the connector assembly with the first and second connectors engaged; 
           [0028]      FIG. 16  is a longitudinal section of the connector assembly shown in  FIG. 15 ; 
           [0029]      FIG. 17  is a perspective of the first connector of the connector assembly shown in  FIG. 15 ; 
           [0030]      FIG. 18  is a perspective of the second connector of the connector assembly shown in  FIG. 15 ; 
           [0031]      FIG. 19  is perspective longitudinal section of the engaged first and second connector of the connector assembly shown in  FIG. 9 ; 
           [0032]      FIG. 19A  is a perspective of the first and second connector separated of the connector assembly shown in  FIG. 9 ; 
           [0033]      FIG. 20  is a perspective of an alternative embodiment of the connector assembly with first and second connectors of the connector assembly engaged; 
           [0034]      FIG. 21  is a perspective of the connector assembly with the first and second connectors separated; 
           [0035]      FIG. 22  is the perspective of  FIG. 20  with the first and second housings removed; 
           [0036]      FIG. 23  is an exploded perspective of the second connector shown in  FIG. 22 ; 
           [0037]      FIG. 24  is a perspective of the first connector assembly shown in  FIG. 20 ; 
           [0038]      FIG. 25  is a longitudinal section taken through opposed channels of a non-sealing surface of the first connector shown in  FIG. 24  showing attempted attachment of a non-permitted conduit; 
           [0039]      FIG. 26  is a perspective of an alternative embodiment of the first connector assembly; 
           [0040]      FIG. 27  is a longitudinal section taken through opposed channels of a non-sealing surface of the first connector shown in  FIG. 26  showing attempted attachment of a non-permitted conduit; 
           [0041]      FIG. 28  is a perspective of a first connector of an alternate embodiment of the connector assembly; 
           [0042]      FIG. 29  is a perspective of a second connector of the connector assembly of  FIG. 28  attached to tubing; 
           [0043]      FIG. 30  is a longitudinal section of the connector assembly of  FIGS. 28 and 29  with the first and second connectors of the connector assembly engaged; 
           [0044]      FIG. 31  is a longitudinal section taken through opposed channels of a non-sealing surface of the first connector in  FIG. 28  showing attempted attachment of a non-permitted conduit; 
           [0045]      FIG. 32  is a perspective of a compression therapy device showing an inflatable bladder and an enlarged view of the connector; 
           [0046]      FIG. 33  is a perspective of a compression therapy device controller with an enlarged view of the connector; and 
           [0047]      FIG. 34  is an enlarged perspective of a tube set. 
       
    
    
       [0048]    Corresponding reference characters indicate corresponding parts throughout the drawings. 
       DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0049]    Referring now to the drawings, a connector assembly  30  constructed according to the principles of the present invention is shown in  FIGS. 1 and 2  to comprise a first connector  36  and a second connector  38 . As described more fully hereinafter, the first and second connectors  36 ,  38  are capable of discriminating connection to preferentially achieve fluid-tight connection of the connectors, and avoid fluid-tight connection with non-complying connectors. The connector system  30  may be used, for example, to connect a controller  2  to a compression therapy device  1  for cyclically supplying air pressure to a bladder  4  of the device (see,  FIGS. 32 and 33 ). The compression therapy device  1  illustrated in  FIG. 32  is of the type which is applied to the foot for repeatedly compressing the foot to force blood out of the foot and discourage pooling of blood in the foot that can lead to clots. Although a foot compression therapy device  1  is illustrated, other types of compression therapy devices can be employed, such as those that are applied to the leg. Other examples of foot and leg devices are disclosed in U.S. Pat. Nos. 5,626,556 and 5,795,312. Moreover, the connector assembly  30  can be used for other types of medical fluid connections such as the connection of an enteral feeding bag to a patient. 
         [0050]    In the illustrated example, a tube set  20  ( FIG. 34 ) is used to selectively interconnect the compression therapy device  1  and the controller  2 . The first connector  36  is attached to a first tubing  32  of the tube set  20 , and the second connector  38  is attached to a second tubing  34  extending from the bladder  4  of the compression therapy device  1  ( FIG. 32 ). A third connector  10  having substantially the same construction as the first connector  36  is attached to the controller  2  ( FIG. 33 ), and a fourth connector  26  having substantially the same construction as the second connector  38  is attached to the opposite end of the tubing  32  of the tube set  20  ( FIG. 34 ). In order to make fluid connection for delivering of pressurized air from the controller  2  to the compression therapy device  1 , the fourth connector  26  of the tube set  20  is engaged with the third connector  10  of the controller, and the first connector  36  of the tube set is engaged with the second connector  38  of the compression therapy device. Because of the structural identity of the first connector  36  and third connector  10 , and of the second connector  38  and the fourth connector  26 , only the first and second connectors will be described in detail hereinafter. 
         [0051]    Referring to  FIGS. 1-6 , the first connector  36  has an attachment portion  40  that accepts the tubing  32 . However, the attachment portion  40  could be directly connected to an object other than tubing, such as the third connector  10  is directly connected to the controller  2  ( FIG. 33 ). The second connector  38  has an attachment portion  80  and a receptacle  78 . The receptacle  78  has a roughly hourglass shape, so the user can grasp and hold the connector assembly  30  and to aid the user in engaging the second connector  38  to the first connector  36 , as shown in  FIG. 1 . 
         [0052]    Referring to  FIG. 2 , a coupling portion  42  of the first connector  36  has a first end  44  and a second end  46 . The second end  46  is suitably attached to the attachment portion  40 , such as by solvent bending or RF welding, or may be formed as one piece of material with the attachment portion. The attachment portion  40  is sealingly received in the tubing  32  of the tube set  20  ( FIG. 34 ). The coupling portion  42  includes a sealing surface  48  and a non-sealing surface  52 . The sealing surface  48  extends around the perimeter of the coupling portion  42  at the second end  46 . The shape and contour of the coupling portion  42  is not restricted to that of the illustrated embodiment, so long as the coupling portion can engage and form a seal with the second connector  38 , as will be described. The non-sealing surface  52  has a greater diameter than the sealing surface  48 . A number of circumferentially spaced channels  58  in the non-sealing surface  52  extend lengthwise of the first connection  36 . Two of the channels  58  communicate with openings  60  extending radially through the first connector  36  to an inner surface  54  thereof. The channels  58  and openings  60  operate to inhibit the formation of a sealing connection. 
         [0053]    The receptacle  78  of the second connector  38  has an interior surface  74  and an annular shoulder  75  at the inner end of the interior of the receptacle ( FIG. 3 ). The shoulder  75  defines a stop surface that limits the distance the first connector  36  can be inserted into the receptacle  78  and axially positions the first connector  36  with respect to the receptacle  78 . An annular sealing flange  76  projects radially inward of the inner surface  74  of the receptacle  78  near the open end of the receptacle. As illustrated, the sealing flange  76  is formed as one piece of material with the receptacle  78 . However, a sealing member (not shown) may be formed separately from the receptacle (e.g., as an O-ring) and secured to the receptacle such as by being received in a circumferential groove formed in the inner surface of the receptacle. 
         [0054]    The user must push, in the direction of the arrow “A” in  FIG. 2 , the first end  44  of the first connector  36  into the receptacle  78  of the second connector  38 , such that the non-sealing surface  52  passes beyond the sealing flange  76 . Unless the user pushes the connectors  36 ,  38  together, a fluid tight seal will not form because of longitudinal channels  58  disposed about the outer surface of coupling portion  42 . The sealing flange  76  cannot conform into the channels  58  that extend past the flange allowing fluid to pass the flange on the non-sealing surface  52  of the first connector  36 . However, when the sealing surface  48  moves into registration with the sealing flange  76 , the flange is able to sealingly conform to the sealing surface to make a fluid tight connection with the sealing surface. 
         [0055]    The open space defined by the longitudinal channels  58  prevents flush engagement of coupling portion  42  with the surface of a non-compliant connector or fluid conduit (lumen). The longitudinal channels  58  may have widths, depths, or lengths other than illustrated herein. One or more longitudinal channels  58  may be oriented parallel, offset, or undulating with the longitudinal axis of the connector  30 . The longitudinal channels  58  can be replaced with a raised surface or roughness on the non-sealing surface  52 . In addition, the openings  60  defined through a wall  62  help prevent a fluid seal between the first connector  36  and a non-compliant connector. An opening  60  is not limited to size and shape provided the opening leaks with a non-compliant connector attached to the first connector  36 . One or more openings  60  diametrically opposed about the wall  62  facilitate leakage with a non-compliant connector. 
         [0056]    An inner surface  54  of the first connector  36  and inner surface  74  of the second connector  38  form a fluid pathway therethrough. The inner surfaces ( 54 ,  74 ) are formed to pass fluid according to the particular flow requirements of a medical system such as the controller  2  and compression therapy device  1 . Attachment portion  40  or attachment portion  80  is not restricted to one port. A “Y” connector  84  ( FIG. 2A ) is releasably attachable to the attachment portion ( 40 ,  80 ) of either connector  36 ,  38  to increase the number of fluids or divert pressurized air to more than one bladder, in the case of compression sleeve. 
         [0057]      FIG. 3  illustrates the connector assembly engaged, without the tubing  32 ,  34  attached. In use, the first tubing  32  (not shown in  FIG. 3 ) is sealingly attached to an inner surface  82  of the attachment portion  80 . The second tubing (not shown in  FIG. 3 ) is attached to attachment portion  40 . The point contact “P” seals the connector assembly  30  upon contact between the sealing flange  76  and the sealing surface  48  of the first connector  36 . The tubing  32 ,  34  is attached in a suitable manner such as by using solvent bonding, RF welding, or other attaching means known in the art. 
         [0058]      FIGS. 4 and 5  show a transverse wall  68  at the first end  44  of the first connector  36 . The transverse wall  68  has a longitudinal cavity  70  across its face. The transverse wall  68  extends along the longitudinal axis for substantially the length of the non-sealing surface  52  and inhibits the insertion of tubes or other connectors (not shown) into the first connector  36 . One or more longitudinal cavities  72  extend along the inner surface  56  at the first end  44 . The non-sealing surface  52  has a first face  64  with transverse cavities  66  disposed at spaced locations around the perimeter of the first face  64 . Each transverse cavity  66  connects to a corresponding one of the longitudinal channels  58  formed in the wall  62  of the coupling portion  42  of first connector  36 . This allows fluid to escape between the first connector  36  and a non-compliant connector. Likewise, the openings  60  allow fluid to escape when a seal is not formed with the sealing surface  48 . The number and arrangement of channels  58 , openings  60  and cavities  66  may be other than described without departing from the scope of the present invention. 
         [0059]    The cavities  66  prevent a seal between the first face  64  and a surface of a non-compliant connector. Each cavity  66  aligns with its corresponding outer longitudinal channels  58  to provide a path for leakage when the first connector  36  is inserted into a non-compliant connector. The transverse wall  68  prevents inserting a non-compliant connector into the first connector  36 . The cavity  70  helps prevent a sealing surface between the first face  64  and a surface of a non-complaint connector. Likewise, inner longitudinal cavities  72  and the openings  60  though the wall  62  help prevent sealing with a non-compliant connector on the inside or outside of the first connector  36 . The open spaces defined by the cavities  66  prevent flush engagement with coupling portion  42  and a surface of a non-compliant connector. A cavity or channel ( 66 ,  70 ,  72 ,  58 ) is not limited to a specific width, depth, or length. A cavity or channel ( 66 ,  70 ,  72 ,  58 ) is not restricted to orientation and can be parallel, offset or undulating. The present invention is not restricted to one non-sealing surface  52  or one sealing surface  48 . 
         [0060]      FIGS. 7 and 8  illustrate an alternative connector assembly  130 . Parts of the connector assembly  130  generally corresponding to those of the connector assembly  30  will be given the same number, plus “100.” A. first connector  136  of the connector assembly  130  has a first end  144  and a second end  146 . Located generally between the first and second ends  144 ,  146  is a sealing surface  148 . The coupling portion  142  is rectangular with rounded corners and sized to fit into the opening of a second connector  138 , in the direction of arrow “A”. The second connector  138  defines a receptacle in a housing of the second connector to receive the first connector  136 . An outwardly flared non-sealing surface  152  is located at the open end of the second connector  138 . Triangular channels  158  in the non-sealing surface provide fluid communication paths to locations outside the connectors  136 ,  138  to inhibit sealing. 
         [0061]    The user holds the second connector  138  using raised ribs  178  to grip and insert the first connector  136  into the second connector  138 . In addition to functioning as grips, the ribs  178  also prevent a sealing connection between the second connector  138  and a tube or the like (not shown) received over the exterior of the second connector. The first connector  136  is inserted with its first end  144  passing beyond a sealing flange  176  located inside the second connector  138 . The resilient sealing flange  176  conforms to the sealing surface  148  to form a fluid tight seal, after the sealing surface  148  passes beyond the non-sealing surface  152  and engages the flange  176 . The user stops applying force when the face of the first end  144  abuts a shoulder  175  a distance beyond the sealing flange  176  of the second connector  138 . A bar  181  is located at the inner end of the second connector  138  to inhibit a tube (not shown) from sealingly abutting a first tube  132  inserted inside an attachment portion  180  of the second connector. 
         [0062]    The first tubing  132  forms a sealing interference fit with the inner surface  182  of the attachment portion  180 . A second tubing  134  is inserted over an attachment portion  140  ( FIG. 8 ), at the second end  146  of the coupling portion  142 . The first and second tubings  132 ,  134  are attached in suitable ways to the first and second connectors  136 ,  138 . This forms a fluid conduit as part of a medical system when properly connected. 
         [0063]      FIGS. 9 and 10  illustrate a connector assembly  230  comprising a key  252  and a mating cavity  290 . Parts of the connector assembly  230  corresponding to those of the connector assembly  30  are given the same reference numeral, plus “200.” When the key  252  is positioned in the cavity  290 , the user has established a fluid-tight seal within the connector assembly  230 . The connector assembly  230  comprises a first connector  236  and a second connector  238 . The first connector  236  has a tubular attachment portion  240  secured to an interior of a housing  241  of the first connector. The attachment portion  240  can be sealingly received in a (second) tubing  234 . The second connector  238  has an attachment portion  280  that can attach the second connector to a (first) tubing  232 . The second connector  238  includes a housing  281  that mounts the attachment portion  280  by way of a flange  283  of the attachment portion. A gasket  276  (broadly, “a sealing member”) mounted by the housing  281  is generally tubular in shape and includes ears  276   a  that are received in correspondingly shaped openings  277  in the housing  281 . The gasket  276  is received around and sealingly engages an exterior surface of the attachment portion  280  axially inward of the mounting flange  283 . 
         [0064]    Coupling portion  242  is slidingly and sealingly received by a first end of second connector  238  into the gasket  276  to form a sealing connection between the first and second connectors. The key  252  snaps into the mating cavity  290  to releasably lock the first and second connectors  236 ,  238  is sealing connection. To release the first connector  236 , the user depresses a button  286 , with raised edges, and pulls the first connector  236  from the second connector  238 , while holding the second connector  238 . Depressing the button  286  deforms the first connector and moves the key  252  laterally out of the cavity  290 . The key  252  prevents engagement with a non-compliant connector (not shown). 
         [0065]    An alternate embodiment of a keyed connector assembly  530  illustrated in  FIGS. 19 and 19A  is similar to the keyed connector assembly  230  of  FIGS. 9 and 10 . Parts of the connector assembly  530  corresponding to those of the connector assembly  30  are given the same reference numeral, plus “500.” The first connector  536  comprises a key  552 , guide flanges  553  and an inner rigid lumen or conduit  548  including an attachment portion  540 . The second connector  538  comprises a mating cavity  590 , an inner sealing member  588 , and finger grips  578  An attachment portion  580  located within the second connector  538  includes an inner part  580   a  that is sealingly attached to the sealing member  588 , and an outer part  580   b  that can be attached to tubing (not shown). In operation, the user grips the second connector  538  at the finger grips  578 , grips the first connector  536  and then pushes the key  552  toward the cavity  590  until it snaps into the cavity. The flanges  553  engage the second connector  538  and help guide the first connector  536  into sealing engagement with the second connector. The inner end of the conduit  548  is received in the sealing member  588  and seals with the sealing member by engagement with an annular protrusion  576  in the sealing member. In this way, a sealing connection of the first and second connectors  536 ,  538  can be made. 
         [0066]      FIGS. 11-14  illustrate still another alternate embodiment of a connector assembly  330 . Parts of the connector assembly  330  corresponding to those of the connector assembly  30  are designated by the same reference numerals, plus “300.” Connector assembly  330  comprises a first connector  336  ( FIG. 13 ), and a second connector  338  ( FIG. 14 ). First connector  336  has an attachment portion  340  ( FIG. 12 ) that accepts tubing (not shown) on the inner surface  341  of the attachment portion  340 . The second connector  338  ( FIG. 14 ) has an attachment portion  380  at a first end and a cap  374  at the second end. A second tubing (not shown) can be received on attachment portion  380 . Spaced a distance from the second end is a deformable O-ring  376  around the perimeter of the cap  374 . The O-ring  376  is releasably attached to the cap  374 . It will be understood that a sealing member can be formed in any suitable manner such as an O-ring (as shown) or a raised surface of deformable plastic. 
         [0067]    The first connector  336  further comprises a coupling portion  342  with at least one longitudinal channel  372  therethrough ( FIG. 13 ). A plurality of non-sealing surface  352  areas ( FIGS. 12 and 13 ) are disposed on the inside of the coupling portion  342 . The non-sealing surfaces  352  have longitudinal channels  358  disposed on the inner surface of the first connector  336  to prevent a fluid seal with a non-compliant connector. The axially inner longitudinal channels  358  are also disposed on both sides of a groove  349  that defines the sealing surface  348  ( FIG. 13 ). At the face of the coupling  342  are disposed a plurality of longitudinal channels  372  ( FIG. 13 ). The open space defined by the channels  372  prevents the coupling portion  342  from forming a fluid seal with a surface of a non-compliant connector. 
         [0068]    In operation, the user inserts the cap  374  into the opening at the coupling portion  342 . The O-ring  376  is deformed as it moves over the non-sealing surfaces  352  under the force of the user. The O-ring  376  comes to rest in the groove  349  and engages the sealing surface  348  ( FIG. 13 ), to form a fluid tight seal. 
         [0069]      FIGS. 15-18  illustrate a further embodiment of a connector assembly  430 . Parts of the connector assembly  430  corresponding to those of the connector assembly  30  are given the same reference numerals, plus “400.” Connector assembly  430  includes a first connector  436  and a second connector  438 . The first connector  436  has an attachment portion  440  that can be attached to a lumen (not shown) which fluidly communicates with a fluid source. A lumen (or tubing) is received on an outer surface of attachment portion  440  and forms a fluid-tight seal therewith. The first connector  436  has a coupling portion  442  comprising a sealing surface  448  and a pair of non-sealing surfaces  452  and each non-sealing surface  452  having longitudinal channels  458  ( FIG. 17 ) disposed on the inner and outer surfaces of the coupling portion  442 . The longitudinal channels  458  are disposed on either side of the sealing surface  448 . The longitudinal channels  458  prevent a sealing engagement with the coupling portion  442  by a non-compliant connector. A longitudinal channel  458  can be oriented anywhere along the perimeter of the coupling portion  442  and can be of varying length, width or depth. A generally annular detent  479  (broken by channels  458 ) extends around the first connector  436 . 
         [0070]    The non-sealing surface  452  includes a first face  464 . The first face  464  includes a transverse wall  468  that extends across the diameter of coupling portion  442 . Transverse wall  468  is configured to prevent sealing engagement of the surface of coupling portion  442  with a non-compliant connector. 
         [0071]    The second connector  438  comprises an attachment portion  480 , a cap  474 , an O-ring  476  inside the cap and sealingly mounted on the cap, and a flex collar  477  ( FIGS. 16 and 18 ). In operation, the user pushes the second connector  438  onto the coupling portion  442 , with the first face  464  entering the opening of the second connector  438 , at the flex collar end. The  0 -ring  476  engages the leading non-sealing surface  452  and does not establish a sealing connection with the non-sealing surface because of the channels  458 . The O-ring  476  next engages the sealing surface  448  as the first connector  436  is advanced farther into the second connector  438  and establishes a sealing connection between the first and second connectors. The detents  479  of the first connector  436  are received in annular grooves  478  on the interior of the flex collar  477 . The flex collar, which has been deflected from its relaxed position, bears against the detents  479  and holds them in the grooves  478  for securing the first and second connectors  436 ,  438  together. 
         [0072]      FIGS. 20-25  illustrate a further embodiment of a connector assembly  630 . Parts of the connector assembly  630  corresponding to those of the connector assembly  30  are given the same reference numerals, plus “600.” The connector assembly  630  includes a first connector  636  and second connector  638  The first connector  636  includes a first housing  657 , attachment portion  640 , and coupling portion  642  and the second connector  638  includes a second housing  659 , attachment portion  680 , and receptacle  678 . The first and second housings  657 ,  659  are removed in  FIGS. 22 and 23  to better illustrate other features of the first and second connectors  636 ,  638 . The first connector  636  may be integral with or secured to another object or device such as a wall  643  (only a fragmentary portion being illustrated) of the housing of a controller like the controller  2  shown in  FIG. 33 . The attachment portion  640  of the first connector  636  accepts tubing (riot shown, but like medical tubing  32 ) that extends from the pump within the controller. However, the attachment portion  640  could be directly connected to an object other than tubing 
         [0073]    Referring to  FIG. 22 , the coupling portion  642  of the first connector  636  has a first end  644  and a second end  646 . The second end  646  is suitably attached to the attachment portion  640 , such as by solvent bonding or RF welding, or may be formed as one piece of material with the attachment portion. The attachment portion  640  may be sealingly received in tubing (e.g., tubing  32  of the tube set  20  ( FIG. 34 )). The coupling portion  642  includes a sealing surface  648  and a non-sealing surface  652 . The non-sealing surface  652  is closer to the free end of the first connector  636  than the sealing surface  648 . The sealing surface  648  extends around the perimeter of the coupling portion  642  at the second end  646 . The shape and contour of the coupling portion  642  is not restricted to that of the illustrated embodiment, so long as the coupling portion can engage and form a seal with the second connector  638 , as will be described. The non-sealing surface  652  has a greater diameter than the sealing surface  648 . A number of circumferentially spaced channels  658  in the non-sealing surface  652  extend lengthwise of the first connector  636 . The channels  658  operate to inhibit the formation of a sealing connection with an interior surface of medical tubing. 
         [0074]    The second connector  638  has a deformable O-ring  663  at the end of the receptacle  678  opposite the attachment portion  680 , which is captured by a cap  655 . Referring now to  FIG. 23 , the cap  655  fits over the O-ring  663  and makes a snap connection with a tapered end  665  of the receptacle  678  to capture the O-ring between the cap and the face  667  of the receptacle. Once captured, the O-ring  663  protrudes radially inward from between the end face  667  of the receptacle  678  and the cap  655  such that the O-ring can sealingly engage the sealing surface  648  of the first connector  636  when the first connector  636  is received in the second connector  638 . The attachment portion  680  of the second connector  638  tapers in diameter toward its middle to facilitate gripping of the second connector assembly  639 . The attachment portion  680  may sealingly receive generic tubing (e.g., tubing  32  of the tube set  20  ( FIG. 34 )). 
         [0075]    Referring to  FIGS. 20 and 21 , the second connector  638  includes a key  611  having a projecting member  621 . The first connector  636  includes a mating cavity  613 . To form a seal between the first connector  636  and the second connector  638 , the user must push the first end  644  of the first connector through the  0 -ring  663  and into the receptacle  678  of the second connector  638 , such that the non-sealing surface  652  passes beyond the O-ring. When the key  611  of the second connector  638   639  is positioned in the mating cavity  613  of the first connector  636  to such an extent that the projecting member  621  abuts the first housing  657 , the sealing surface  648  has engaged the O-ring  663 . Abutment of the projecting member  621  and the first housing  657  prevents separation of the first connector  636  and the second connector  638 . To release the second connector  638 , the user depresses the projecting member  621  and pulls the first connector  636  from the second connector  638 , while holding the second connector. Depressing the projecting member  621  moves the projecting member out of the mating cavity  613 . 
         [0076]    Referring to  FIGS. 24 and 25 , the first housing  657  of the first connector  636  includes a floor  671 . The coupling portion  642  projects outward from the floor  671 . Standoff ribs  675  that project outward from the housing floor  671  are circumferentially spaced about the coupling portion  642 . The end of each standoff rib  675  adjacent the coupling portion  642  is attached to a connecting segment  681  that circumferentially surrounds the coupling portion. Bleed passages generally indicated at  679  are defined beyond the connecting segments  681  and between the ribs  675  and floor  671 . The bleed passages  679  extend past the end face of a conduit such as generic medical tubing, when the conduit is fully inserted onto the coupling portion  642  that allows fluid to be bled around the coupling portion to prevent a fluid-tight seal. The direction and pathway of flow is generally indicated by arrow “A” ( FIG. 25 ). The bleed passages  679  prevent successful fluid-tight connection between the coupling portion and medical tubing MT (a “non-permitted conduit”) when the end face of the medical tubing is pushed all the way into the first housing  657  as illustrated in  FIGS. 25 . In this condition, a typical controller can sense the absence of the fluid tight connection and initiate an alarm. 
         [0077]      FIGS. 26 and 27  illustrate a further embodiment of the first connector  736 . Parts of the first connector  736  corresponding to those of the connector  636  are given the same reference numerals, plus “100.” Bleed passages  779  are formed in the first connector  736  and located generally adjacent the floor  771  of the housing  757  for bleeding fluid around the coupling portion  742 . Referring now to  FIG. 26 , the bleed passages  779  open radially outward of the coupling portion  742  at a first opening and extend axially through the housing floor  771  and open from the first connector at the side of the floor opposite the first opening. A non-sealing surface  752  of the coupling portion  742  holds conventional medical tubing MT (a “non-permitted conduit”) from sealing with the sealing surface  748 . An end face of the tubing MT may seal with the floor  771 , However, the bleed passages  779  formed in the sealing surface  748  are not sealed. Thus, air in the medical tubing MT may pass through the channels  758  in the non-sealing surface  752 , along the sealing surface  748  and out the bleed passages  779  as indicated by arrow “B” ( FIG. 27 ). Therefore, no fluid-tight connection can be made with standard medical tubing MT, even if the end face of the tubing otherwise seals with the floor  771 . 
         [0078]      FIGS. 28-31  illustrate a further embodiment of a connector assembly  830 . Parts of the connector assembly  830  corresponding to those of the connector assembly  30  are given the same reference numerals, plus “800.” The connector assembly  830  comprises a first connector  836  and a second connector  838  ( FIGS. 28 and 29 ). The first connector  836  has a tubular and barbed attachment portion  840  secured to a gripping portion  841  of the first connector and located in an interior of the gripping portion ( FIG. 30 ). The attachment portion  840  can be sealingly received in tubing  834 . However, the attachment portion  840  could be directly connected to an object other than tubing, in the same way as the third connector  10  is directly connected to the controller  2 . The second connector  838  has an attachment portion  880  that can attach the second connector to generic tubing  832  (e.g., like tubing  32  of the tube set  20  ( FIG. 34 )). 
         [0079]    The second connector  838  includes a receptacle  878 . The receptacle  878  mounts to the attachment portion  880  by way of a flange  883 . The receptacle  878  has an interior surface  874  and an annular shoulder  875  at the inner end of the interior of the receptacle ( FIG. 30 ). The shoulder  875  defines a stop surface that limits the distance the first connector  836  can be inserted into the receptacle  878  and axially positions the first connector  836  with respect to the receptacle  878 . 
         [0080]    The surface of the gripping portion  841  of the first connector  836  and the surface of the attachment portion  880  of the second connector  838  include raised ridges  814 ,  824 . The raised ridges  814  of the first connector  836  include two generally opposed parentheses shaped first ridges  814   a  that extend generally lengthwise of the first connector and two flattened U-shaped second ridges  814   b  spaced lengthwise of the first connector and located between the first ridges ( FIG. 28 ). Likewise, the raised ridges  824  include first ridges  824   a  and second ridges  824   b  shaped and arranged in the same way as the first ridges  814   a  and second ridges  814   b  (see,  FIG. 29 ). In the illustrated embodiment, the first and second ridges  814   a,    814   b  and  824   a,    824   b  are arranged to define channels  822 ,  828  (respectively) for the passage of air along the connector  836 ,  838 . The raised ridges generally indicated at  814  and  824 , respectively, prevent a fluid-tight seal from forming when generic medical tubing is placed over the surface of the gripping portion  841  or of the attachment portion  880 . Channels  822 ,  828  defined by the raised ridges  814 ,  824  carry fluid away from the connectors  836 ,  838  in a direction generally indicated by arrow “A” if such tubing (not shown) is placed over the connectors thereby inhibiting a fluid tight connection of either of the connectors  836 ,  838  with the medical tubing. The second ridges  814   b,    824   b  help to prevent highly conforming tube material from sealing with and between the first ridges  814   a,    824   b.    
         [0081]    It is to be understood that the ridges  814  and  824  may have shapes and arrangements that are different from what is illustrated and different from each other within the scope of the present invention. As shaped and arranged in the illustrated embodiment, the ridges  814 ,  824  provide for the passage of air, but also facilitate gripping the connector  836 ,  838 . In the illustrated embodiment there are ridges (not shown) just like the ridges  814 ,  824  that may be seen in  FIGS. 28 and 29 , but which are located in the opposite sides of the connectors  836 ,  838 . 
         [0082]    Referring to  FIG. 28 , the gripping portion  841  of the first connector  836  has a flange  815  formed at a distal end. The first connector  836  includes a coupling portion  842  and a floor  871 . The diameter of the floor  871  is generally the same as the diameter of the flange  815 . The floor  871  and flange  815  include bleed passages  817  at their perimeters to prevent a fluid-tight seal when medical tubing is placed over the perimeters of the flange and floor. Another pair of bleed passages (not shown) like bleed passages  817  are located at the opposite side of the connector  836 . It will be understood that any number of bleed passages may be employed within the scope of the present invention. 
         [0083]    The first connector  836  includes a coupling portion  842  that projects outward from the floor  871 . Standoff ribs  875  that project outward from the floor  871  are circumferentially spaced about the coupling portion  842 . Bleed passages generally indicated at  879  are defined between the ribs  875  and floor  871 . The bleed passages  879  are recessed from the ribs  875  and communicate with bleed passages  817 . If a medical tube MT that is too small to receive the entire connector  836  therein is pushed over the coupling portion  842  as illustrated in  FIG. 31 , an end of the tubing engages the ribs  875  and is held off the floor  871 . Air may flow out of the tube, into the bleed passages  879  to bleed passages  817  or directed radially outward of the first connector  836 . The direction and pathway of flow is generally indicated by arrow “A” ( FIG. 31 ). The bleed passages  817 ,  879  prevent successful fluid-tight connection between the coupling portion  842  and medical tubing when the end face of the medical tubing is pushed all the way to the floor  871 . 
         [0084]    The coupling portion  842  includes a sealing surface  848  and a non-sealing surface  852 . The non-sealing surface is closer to the free end of the first connector  836  than the sealing surface  848 . The sealing surface extends around the perimeter of the coupling portion  842 . The shape and contour of the coupling portion  842  is not restricted to that of the illustrated embodiment, so long as the coupling portion can engage and form a seal with the second connector  838 , as will be described. The non-sealing surface  852  has a greater diameter than the sealing surface  848 . A number of circumferentially spaced channels  858  in the non-sealing surface  852  extend lengthwise of the first connector  836 . The channels  858  operate to inhibit the formation of a sealing connection of the coupling portion  842  with an interior surface of medical tubing. 
         [0085]    The second connector  838  has a deformable O-ring  863  at the end of the receptacle  878  opposite the attachment portion  880 . The O-ring  863  protrudes radially inward and is positioned axially so that the O-ring can sealingly engage the sealing surface  848  of the first connector  836  when the first connector  836  is received in the second connector  838  to make a fluid-tight connection. In this way, essentially only desired connections are allowed. 
         [0086]    For the preferred embodiments described herein, the connectors are fabricated from semi-flexible and flexible materials suitable for vascular compression therapy such as, for example, polymeric materials, depending on the particular vascular therapy application and/or preference. Urethanes and silicones may also be used. One skilled in the art, however, will realize that other materials and fabrication methods suitable for assembly and manufacture, in accordance with the present disclosure, also would be appropriate. A number of alternating sealing and non-sealing surfaces is possible depending on the size and shape of the connector assembly. 
         [0087]    When introducing elements of the present invention or the preferred embodiments(s) thereof, the articles “a”, “an”, “the” and “said” are intended to mean that there are one or more of the elements. The terms “comprising”, “including” and “having” are intended to be inclusive and mean that there may be additional elements other than the listed elements. 
         [0088]    In view of the above, it will be seen that the several objects of the invention are achieved and other advantageous results attained. 
         [0089]    As various changes could be made in the above embodiments and methods without departing from the scope of the invention, it is intended that all matter contained in the above description and shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.