Patent Publication Number: US-8986243-B2

Title: Peritoneal dialysis patient connection system

Description:
PRIORITY CLAIM 
     This application claims priority to and the benefit as a continuation application of U.S. Patent Application entitled, “Peritoneal Dialysis Patient Connection System”, Ser. No. 11/773,623, filed Jul. 5, 2007, now abandoned, the entire contents of which are incorporated herein by reference and relied upon. 
    
    
     BACKGROUND 
     The present disclosure relates generally to medical device connectors and more specifically to patient connectors for peritoneal dialysis. 
     Due to various causes, a person&#39;s renal system can fail. Renal failure produces several physiological derangements. The balance of water, minerals and the excretion of daily metabolic load is no longer possible and toxic end products of nitrogen metabolism (urea, creatinine, uric acid, and others) can accumulate in blood and tissue. 
     Kidney failure and reduced kidney function have been treated with dialysis. Dialysis removes waste, toxins and excess water from the body that would otherwise have been removed by normal functioning kidneys. Dialysis treatment for replacement of kidney functions is critical to many people because the treatment is life saving. 
     One type of kidney failure therapy is peritoneal dialysis, which uses a dialysis solution, also called dialysate, which is infused into a patient&#39;s peritoneal cavity via a catheter. The dialysate contacts the peritoneal membrane of the peritoneal cavity. Waste, toxins and excess water pass from the patient&#39;s bloodstream, through the peritoneal membrane and into the dialysate due to diffusion and osmosis, i.e., an osmotic gradient occurs across the membrane. The spent dialysate is drained from the patient, removing waste, toxins and excess water from the patient. This cycle is repeated. 
     There are various types of peritoneal dialysis therapies, including continuous ambulatory peritoneal dialysis (“CAPD”), automated peritoneal dialysis (“APD”), tidal flow dialysate and continuous flow peritoneal dialysis (“CFPD”). 
     The technique of CAPD to remove impurities from the blood of a patient whose kidneys have failed permits the patient being dialyzed to carry a surgically implanted catheter, which is generally connected (intermittently) to a peritoneal dialysis transfer set. For CAPD treatment, the transfer set, in turn, is connected to a bag of peritoneal dialysis solution, which is emptied through the transfer set into the peritoneal cavity (CAPD infusion phase). For CAPD, the patient is not “tied” to a machine and can be ambulatory while the dialysis across the peritoneal membrane (CAPD dwell phase) occurs. After the dwell phase, the peritoneal dialysis solution is drained (CAPD drain phase) from the peritoneal cavity. This can be done by allowing the solution to flow back into the supply bag; there is preferably no disconnection of the bag during the dwell phase. After the drain phase, the bag with spent peritoneal dialysis solution may be disconnected from the transfer set and discarded. 
     Automated peritoneal dialysis (“APD”) is similar to CAPD in that the dialysis treatment includes drain, fill, and dwell cycles. APD machines or “cyclers”, however, perform the cycles automatically, typically while the patient sleeps. APD machines free patients from having to manually perform the treatment cycles and from having to transport supplies during the day. APD machines connect fluidly to an implanted catheter, to a source or bag of fresh dialysate and to a fluid drain. APD machines pump fresh dialysate from a dialysate source, through the catheter, into the patient&#39;s peritoneal cavity, and allow the dialysate to dwell within the cavity, and allow the transfer of waste, toxins and excess water to take place. The source can be multiple sterile dialysate solution bags. 
     APD machines pump spent dialysate from the peritoneal cavity, though the catheter, to the drain. As with the manual process, several drain, fill and dwell cycles occur during dialysate. A “last fill” occurs at the end of CAPD and APD, which remains in the peritoneal cavity of the patient until the next treatment. 
     Both CAPD and APD are batch type systems that send spent dialysis fluid to a drain. Tidal flow systems are modified batch systems. With tidal flow, instead of removing all of the fluid from the patient over a longer period of time, a portion of the fluid is removed and replaced after smaller increments of time. 
     Continuous flow, or CFPD, systems clean or regenerate spent dialysate instead of discarding it. The systems pump fluid into and out of the patient, through a loop. Dialysate flows into the peritoneal cavity through one catheter lumen and out another catheter lumen. The fluid exiting the patient passes through a reconstitution device that removes waste from the dialysate, e.g., via a urea removal column that employs urease to enzymatically convert urea into ammonia. The ammonia is then removed from the dialysate by adsorption prior to reintroduction of the dialysate into the peritoneal cavity. Additional sensors are employed to monitor the removal of ammonia. CFPD systems are typically more complicated than batch systems. 
     All of the above systems require the patient to connect the patient&#39;s indwelling catheter to a PD supply apparatus via a transfer set. The patient connection must be kept sterile or the patient can suffer from a condition called peritonitis. The patient connection should also be easy for the patient to make and unmake because the patient is usually performing these tasks at home and/or alone. Accordingly, a need exists for improved peritoneal dialysis patient connection systems. 
     SUMMARY 
     The present disclosure includes an improved patient connector or patient assist system for medical fluid systems including peritoneal dialysis (“PD”). In particular, the connectors and connections relate to patient connectors and connections for any type of PD, such as automated peritoneal dialysis (“APD”) and continuous ambulatory peritoneal dialysis (“CAPD”). The patient connection system generally includes a patient transfer set having a spine connector. A female or port connector of a bag supply line (“CAPD”) or cycler patient line (“APD”) connects to the spike connector of the patient&#39;s transfer set. The female and spike connectors are positioned in a connection mechanism, which is described below as being a rotating drum type of mechanism. The rotating drum mechanism is in turn placed moveably within a housing having ultraviolet light (“UV”) applicator positioned to sterilized connectors loaded into the drain mechanism. 
     The housing in one embodiment includes a lid connected hingedly to a lower portion of the housing. Half of the drain device is fitted to and latches with the lid. The other half is fitted into the lower portion. The device halves can then be separated to load and unload the connectors and plugs. The UV applicator is also split into the lid and lower portion and embedded so to be positioned on the outsides of the drain device when load into the lid and lower portion of the housing. 
     The rotational drum connection/disconnection device includes three main components, namely: (i) a female or port holder; (ii) a transfer set holder; and (iii) a slide holder. The port holder is fixed inside of housing, such as one also holding a light applicator housing, which radiates light onto the connectors placed into the drum connection/disconnection device as described in detail below. The port holder in one embodiment holds a female or port connector (connected to a solution line, e.g., from a supply bag directly or from a cycler) and a female plug. 
     The transfer set holder holds a spike or patient connector and rotates and translates relative to the port holder and holds the patient&#39;s transfer set spike connector (connected to patient&#39;s indwelling catheter). The transfer set holder in one embodiment includes and slidingly engages a slide holder, which translates back and forth relative to the remainder of the transfer set holder and the port holder. 
     The slide holder can be part of or separate from the transfer set holder. The slide holder in one embodiment holds a male plug. In one embodiment there are two relative translating movements, (i) the slide holder relative to the remainder of the transfer set holder and the port holder and (ii) the transfer set holder as a whole (including the slide holder) relative to the port holder. In another embodiment, the slide holder is not provided with the transfer set holder such that there is only one translational movement, namely, the transfer set holder as a whole (including the patient connector and male plug) relative to the port holder. 
     When the transfer set holder is rotated relative to the port holder, the slide holder (holding the male plug) rotates with the remainder of the transfer set holder (holding the male spike connector). This motion allows the transfer set holder to flip-flop back and forth between aligning the connectors with each other (connected for treatment) or with a mating plug (disconnected for, e.g., dwell, end of treatment or temporary disconnect). 
     One connection sequence for the above-described patient assist device operates as follows, wherein the device includes a first portion configured to hold a fluid supply connector and a first plug; a second portion configured to hold a patient connector and a second plug; an ultraviolet light (“UV”) applicator; and wherein the first and second portions cooperate with the UV applicator so that: (i) the first plug initially plugs the patient connector and the second plug initially plugs the supply connector, (ii) the first and second portions are translated away from each other via at least one translation mechanism, unplugging the first and second plugs from the patient connector and the supply connector, respectively, (iii) the first and second portions are rotated with respect to each other, (iv) the UV applicator irradiates at least a portion of the fluid supply and patient connectors; and (v) the first and second portions are translated towards each other via the at least one translation mechanism, connecting the patient connector to the supply connector and the first plug to the second plug. 
     One disconnection sequence for the above-described patient assist device operates as follows: (i) the first plug is connected initially to the second plug and the patient connector is connected initially to the supply connector, (ii) the first and second portions are translated away from each other via at least one translation mechanism, disconnecting the first plug from the second plug and the patient connector from the supply connector, (iii) the first and second portions are rotated with respect to each other, (iv) the UV applicator irradiates at least a portion of the patient connector and the supply connector, and (v) the first and second portions are translated with respect to each other via the at least one translation mechanism, connecting the first plug to the patient connector and the second plug to the supply connector. 
     The female or port connector mounted in the port holder of the above-described patient assist connection device has a frangible seal that is manually broken to expose a diaphragm, which prevents flow through the connector. The spike connector includes a spike or piercing end that pierces the diaphragm and inserts into the female connector. The spike can have a cut-away portion at its sharpened end, with the sharpened end defining a pointed edge at one side of the spike opposite the cut-away portion. Such structure results in diaphragm not being cut away from the interior wall of the female connector, so that the diaphragm remains attached to the interior wall of the connector. This prevents the diaphragm passing through the tubular system into the peritoneal cavity of the patient, or falling free to block flow at some point in the system. 
     If desired, the female and spike connectors can be partially or substantially opaque to ultraviolet (“UV”) light if this results in the connectors being made of a less expensive material, and if the interior portions of the connectors are sterilized at the factory. Here, only exterior portions of the connectors have to receive the antimicrobial effects of the UV as described herein. Alternatively, the spike connectors can be made of a UV transmissive material and be sterilized inside and outside upon connection and disconnection (as highlighted above), for example, in addition to being sterilized at the factory. 
     The female or port connector as shown below in one embodiment includes a shroud that tends to prevent the portion of the female connector that interfaces with the spike connector from patient touch during connection and disconnection. The spike connector also includes a sealing portion, e.g., one or more o-ring type annular projection that seals to the inner wall of the shroud. The shroud therefore also serves to prevent the patient from touching the sealing portion after connection. This tends to prevent contamination from entering the female connector upon disconnecting the female and spike connectors. The shroud further serves to prevent over-advancement of the spike connector within the female connector. 
     The shroud and the rotational drum connection/disconnection device are configured such that the shroud of the female connector extends past the port holder of the connection/disconnection device. This allows the female connector to be inserted into the port connector of the rotational drum connection/disconnection device prior to removing a tip protector from an end of the female connector. The tip protector protects the shroud end of the female connector until time for use. Here, the patient can hold the rotational drum connection/disconnection device and pull the tip connector off without having to touch the female connector. This further prevents the female connector from becoming contaminated in the first place and lessens the load on the UV light applicator. 
     An additional advantage of the shroud is that the spike end of the mating patient connector is not contaminated when the patient removes the patient connector and associated spike from the shrouded end of the female supply connector. Such contamination is a common occurrence with known connectors. 
     The spike connector and the female or port connector as discussed above are each connected to a tube on the opposite end from the end at which the spike connector mates with the female connector. In one embodiment, as discussed above, the spike connector is connected to a tube that connects to or is part of the patient&#39;s transfer set and that communicates with the patient&#39;s indwelling catheter. The female or port connector connects to a tube that communicates with a fluid supply, either directly (CAPD) or via a disposable cassette operable with a cycler (APD). In one embodiment, one or both of the spike connector and the female connector includes at least one barbed ring configured to seal the tube to the connector. 
     The barbed ring is tapered such that it is relatively easy to insert the tube over the at least one barbed ring but relatively difficult to remove the tube, making a good, sealed connection. The at least one barbed ring is relatively easy and inexpensive to manufacture and control. 
     In another embodiment, the spike connector and port connector provide a snap-connection. The supply or port connector includes an undercut geometry, which mates with an annular ring of the spike connector to provide connection retention. The snap-fit is configured such that the disconnection device can readily overcome the snap-fitting force to decouple the spike connector from the female or port connector. The patient is also able to readily decouple the connectors by hand. 
     The snap-fit enables the connection of the spike connector to the supply connector to not have to rely on a friction fit between the spike and an inner diameter of the supply connector. The spike connector includes a spike having a stepped-down (diameter) tip, which reduces friction between the connectors and thus insertion and removal forces caused by the mating connectors. 
     It is accordingly an advantage of the present disclosure to provide an improved patient assist system for peritoneal dialysis (“PD”). 
     It is another advantage of the present disclosure to provide a patient assist system operable with continuous ambulatory peritoneal dialysis (“CAPD”) and automated peritoneal dialysis (“APD”). 
     It is yet a further advantage of the present disclosure to provide a patient assist system having an improved connector connection and disconnection device. 
     It is still a further advantage of the present disclosure to provide an improved connector connection and disconnection device, which includes rotating and translating portions. 
     It is still another advantage of the present disclosure to provide an improved female or port connector having a shroud that tends to protect sensitive areas of the connector from human touch and possible contamination. 
     Moreover, it is an advantage of the present disclosure to provide a connector and connection and disconnection device that enables the connectors to be placed in the device prior to removing a tip protector from the connectors, further protecting sensitive areas of the connector from human touch and possible contamination. 
     Still another advantage of the present disclosure is to provide a connector having at least one barbed ring for connecting sealingly to a tube or conduit. 
     Another advantage of the present disclosure is to provide a snap-fitting connection between spike and port connector. 
     A further advantage of the present disclosure is to reduce insertion and removal forces for the spike and port corrector connection and disconnection. 
     Additional features and advantages are described herein, and will be apparent from, the following Detailed Description and the figures. 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         FIG. 1  is a top plan view of one embodiment of a rotational drum connection/disconnection device 
         FIG. 2  illustrates a perspective view of the rotational drum connection/disconnection device of the system of  FIG. 1 , which employs a supply line connector portion fixed to a housing and a patient line connector portion that translates and rotates with respect to the supply line connector portion. 
         FIGS. 3 to 6  further illustrate one embodiment of the rotational drum connection/disconnection and a connection sequence using the rotational drum. 
         FIGS. 7 to 13  are schematic views of a disconnection sequence for the rotational drum connection/disconnection. 
         FIG. 14  is a schematic view of a temporary disconnection/reconnection sequence for one embodiment at the rotational drum connection/disconnection device. 
         FIGS. 15 and 16  are sectioned elevation views illustrating a connector having a shroud tending to protect sensitive areas of the connector from human touch and possible contamination. 
         FIG. 17  is a sectioned elevation view illustrating a connector and holder combination providing an improved tip protector removal sequence, which tends to protect sensitive areas of the connector from human touch and possible contamination. 
         FIGS. 18 and 19  are top and side sectioned views, respectively, of an improved connector with a plurality of barbed sealing bands or rings. 
         FIGS. 20 and 21  are perspective and sectional views of a spike connector having a stepped-down spike end diameter and a spike to port connector snap-fitted connection, respectively. 
     
    
    
     DETAILED DESCRIPTION 
     Drum Disconnection and Reconnection Device 
     The apparatuses and methods discussed herein are is illustrated in use with a peritoneal dialysis system, such as continuous ambulatory peritoneal dialysis (“CAPD”) or an automated peritoneal dialysis (“APD”). It should be appreciated however that the teachings associated with the appended drawings are applicable to many types of medical fluid systems. In CAPD and APD, the patient connects a supply line running to either a supply bag directly (CAPD) or to a disposable cassette (APD) operable with a pumping cycler. It is important that such connection be made in a sterile manner. It is also desirable to have a convenient system for the patient, who may otherwise be ill or elderly, to operate. 
     The patient connects the supply line to a patient line, which can be part of a PD transfer set, which is in turn connected to a catheter dwelling within the patient&#39;s peritoneum. The patient in CAPD then connects the patient line to a drain bag to enable spent dialysate to be removed from the patient&#39;s peritoneum. The patient may have to connect multiple supply lines, each running from a separate supply bag, to the patient line. Between each supply bag for CAPD, the patient has to connect to a drain bag. Here, it is important that the patient be able to disconnect an old supply line, correct a drain line and then connect a new supply line readily and in a sterile environment. 
     It is also possible in CAPD and APD that the patient needs to disconnect from a supply bag or a drain bag during a fill or drain. In both procedures, therefore, it is desirable to have a convenient and sterile way for the patient to disconnect temporarily from the supply or drain connector and then to reconnect to the connector at a later time. 
     The apparatuses and methods provide an improved connection/disconnection device. The connectors being connected are also configured to prohibit the connectors from becoming contaminated in the first place. Still further, (i) a connector to tube connection, and (ii) connector to connector connection sequenced, and (iii) a connector to connector disconnection sequence are improved. 
     Referring now to the drawings and in particular to  FIG. 1 , system  10  illustrates one embodiment for a sterilized rotational/translational connection/disconnection system of the present disclosure. System  10  includes a base  12  onto which occlusion subassembly  20  and a drum rotation subassembly  30  are mounted. Occlusion subassembly  20  includes an occlusion subassembly base  14 , which is bolted to (e.g., set apart from) system subassembly  12 . Occlusion subassembly base  14  supports an occlusion motor  16  coupled to an at least partially threaded shaft  18 . A pillow block  22  supports shaft  18  at its distal end. 
     A translating occluder  24  is threaded onto shaft  18  and is guided on one or two sides so that it cannot rotate when shaft  18  is rotated. Instead, the guides cause translating occluder  24  to translate back and forth when shaft  18  is rotated. In this manner, translating occluder  24  translates towards or away from a stationary occluder  26  to pinch or open a line, respectively, automatically. In one embodiment, the line that is occluded is a supply line running to a supply connector  90 , which is loaded into the drum rotation subassembly  30 . 
     Drum rotation subassembly  30  includes a drum rotation subassembly base  32 , which is bolted to system subassembly  12 . Drum rotation subassembly base  32  supports a drum rotation motor  34  coupled to a first gear  36 . First gear  36  drives a second gear  38 , which through reduction increases the torque output and positionability of drum rotation motor  34 . Drum rotation motor  34  can be a stepper motor, which is inherently accurately positionable. Alternatively, drum rotation motor  34  is an AC or DC bidirectional motor that operates with position sensors monitoring the rotational position of the moveable portion  52   b  of drum connection/disconnection device  50  (discussed in detail below). The sensors tell a controller of motor  34  when the motor should stop spinning in a particular direction. 
     Second gear  38  drives a third gear  40 , which is roughly in a one-to-one ratio with second gear  38 . Third gear  40  is coupled to fourth gear  42 . Fourth gear  42  is configured to mate with a drum gear  44  located at the end of drum connection/disconnection device  52   b  when device  52   b  and gear  44  are translated over fourth gear  42 . 
     Drum rotation subassembly  30  includes a ball screw  46 , which is at least partially threaded. First and second pillow blocks  45  and  47  support either end of ball screw  46 . Ball screw  46  runs underneath drum connection/disconnection device  52   b  as illustrated and is threaded into a block (e.g., located underneath device  52   b ) connected to device  52   b . The threaded block is guided on one or two sides so that it cannot rotate when ball screw  46  is rotated. Instead, the guide(s) cause the block and moveable device  52   b  to translate back and forth when ball screw  46  is rotated. In this manner, the transfer set holder  52   b  translates towards or away from a stationary portion of device  50  (not shown here but described in detail below) to disconnect and reconnect connectors as discussed in detail below, automatically. 
     Motor  34 , gears  36 ,  38  and  40  all drive ball screw  46  and thus the moveable port  52   b  of drum connection/disconnection device  50  in two directions. Gear  42  is a one-way clutch. That is, gear  42  turns drum gear  44  when gears  36 ,  38  and  40  are turned so that gear  42  is turned in a first, e.g., clockwise, direction when viewed from hand crank  48 . However, gear  42  spins freely and does not turn drum gear  44  when gears  36 ,  38  and  40  are turned so that gear  42  would be turned in a second, e.g., counterclockwise, direction when viewed from hand crank  48 . A spring  49  absorbs a shock from drum  50  when gear  44  of drum  50  engages gear  42 . Ball screw  46  in the illustrated embodiment can also be driven manually via crank  48 . 
     Motor  34  (or manual input) and gears  36 ,  38  and  40  turn ball screw  46  in one direction to pull moveable portion  52   b  of drum connection/disconnection device  50  away from the stationary portion (shown below as port holder  52   a ) of device  50  until drum gear  44  comes into operable engagement with fourth free-wheel clutch gear  42 . Once such engagement begins, gear  42  begins to turn drum gear  44  and the moveable portion  52   b  of device  50  rotationally about its axis. That is, when motor  34  (or manual input) and gears  36 ,  38  and  40  are turned such that drum gear  44  and the moveable part  52   b  of device  50  are moving towards gear  42 , gear  42  can clutch drum gear  44  and turn it, turning the moveable part  52   b  of connection device  50 . Eventually, a stop  57  extending from gear  44  engages a stop  59  fixed to the sub-assembly base  32 . Stops  57  and  59  ensure that drum gear  44  and the moveable part  52   b  of connection device  50  rotate a desired one-hundred-eighty degrees. Stops  57  and  59  also cause motor  34  to draw additional current, which can be sensed and serve as a trigger to stop motor  34  from turning in the direction that causes ball screw  46  to move drum gear  44  and the moveable part  52   b  towards stop  59   
     Next, motor  34  (or manual input) and gears  36 ,  38  and  40  turn ball screw  46  in the opposite direction to translate moveable portion  52   b  of drum connection/disconnection device  50  towards the stationary portion of device  50  (not illustrated in  FIG. 1 ) until the various connectors and caps mate as shown below. When the drive train is rotating in this state, gear  42  slips against a hub extending from gear  40 , such that gear  42  does not turn drum gear  44  and the moveable portion of drum  52   b  rotationally. That is, when motor  34  (or manual input) and gears  36 ,  38  and  40  are turned such that drum gear  44  and the moveable part  52   b  of device  50  are moving away from gear  42 , gear  42  does not clutch drum gear  44  and does not turn the gear or the moveable part  52   b  of device  50 . Eventually, a connector and cap loaded into moveable part  52   b  mate with a connector and cap (or vice versa) of stationary part  52   a , signaling the end of travel in the connection direction. 
     Drum subassembly base  32  also supports an ultraviolet (“UV”) light applicator  70 , which is positioned around a the connector mating portion of rotational/translational connection/disconnection device  50 . UV light applicator  70  irradiates the connectors loaded into device  50  during connection and disconnection. As discussed below, UV light applicator  70  can be energized when transfer set holder  52   b  of connection/disconnection device  50  is being rotated in one embodiment. In one embodiment, light applicator  70  is a “UV-Flash”™ applicator provided by the eventual assignee of the present application, which is described U.S. Pat. Nos. 4,412,834 and 4,503,333, owned by the eventual assignee of the present application, the entire contents of both of which are incorporated herein expressly by reference. Another suitable light applicator  70  is disclosed in copending U.S. patent application Ser. No. 11/773,824, filed Jul. 5, 2007, entitled “Peritoneal Dialysis Patient Connection System Using Ultraviolet Light Emitting Diodes”, assigned to the eventual assignee of the present application, the entire contents of which are incorporated herein by reference. 
     Connection/disconnection system  10  includes a housing  64  having a lid  66 , which is connected hingedly to a lower portion  68  of the housing via first and second hinges  72   a  and  72   b . Housing  64  can be plastic, such as a clear plastic, and should be opaque to UV light. As shown in more detail below, in one embodiment, an upper portion  74  of the moveable portion  52   b  of connection/disconnection device  50  is connected to lid  66 . An upper part of port holder  52   a  (shown below) of device  50  is fixed to and rotatable with lid  66 . Upper portion  74  of transfer set holder  52   b  is rotatably and translatably fixed to and rotatable with lid  66 . 
     An upper portion of light applicator  70  is fixed to and rotatable with lid  66  of housing  64 . A lower portion of light applicator  70  is fixed to lower portion  68  of housing  64 . In this manner, light applicator  70  is openable and closeable about connection/disconnection device  50 , which is loaded into housing  64 , a portion  52   c  of which is thereafter translatable and rotatable via lead screw  46  and gears  36 ,  38 ,  40 ,  42  and  44 , respectively, as discussed above. 
       FIG. 2  illustrates one embodiment for the transfer set holder  52   b  of rotational/translational connection/disconnection device  50 . As shown below, device  50  has three primary components, namely, a port holder  52   a , a transfer set holder  52   b  and an optional slide holder  52   c . Each of these parts can but does not have to be made of a UV transmissive material such as poly(trifluorochloroethane), for example sold as KEL-F™ by Minnesota Mining &amp; Manufacturing, or other stable fluorocarbon, for example. Quartz glass, silicone rubber, appropriately stabilized hydrocarbon resin or other resins may be used as well. 
     In  FIG. 1  above, transfer set holder  52   b  is illustrated. Port holder  52   a  is located to the left of transfer set holder  52   b , i.e., above pillow block  45 . Port holder  52   a  is not illustrated in  FIG. 1 , so that occluder sub-assembly  20  and the driving mechanism for transfer set holder  52   b  can be illustrated more completely. Port holder  52   a  is however illustrated in detail in the following drawings. 
     In  FIG. 2 , transfer set holder  52   b  is divided into upper half  74  and lower half  76 , as discussed above, along centerline C L . Lower half  76  of transfer set holder  52   b  includes a slotted groove  54  that slides over and secures to a peg or post  78   a  extending from or connected to a holding well of sub-assembly  30  of system  10  for of lower portion  68  of housing  64 . A similar peg or post  78   a  extends downwardly from a holding well of lid  66  of housing  64 . Upper half  74  of transfer set holder  52   b  of device  50  also includes a slotted groove  54  that slides over and secures to the upper peg or post  78   a . As discussed above, upper and lower parts  74  and  76  of transfer set holder  52   b  along centerline C L  are fixed to and rotatably openable with upper lid  66  and lower portion  68  of housing  64 . Transfer set holder  52   b  includes or defines apertures  56 , split along centerline C L , for accepting and securing a patient connector  80  and a male plug  86  shown below in  FIGS. 3 to 13 . 
     Transfer set holder  52   b  includes a driving slot  58  that slides over and secures in a rotatable manner to a peg  78   b  extending from an apparatus (not seen in  FIG. 2 ) threaded onto and driven translatably by lead screw  46 . Peg  78   b  pushes and pulls upper half  74  and lower half  76  (which lock together when lid  66  of housing  64  is closed onto lower portion  68  of housing  64 ) of transfer set holder  52   b  towards and away from, respectively, stationary port holder  52   a  when lead screw  46  is turned (e.g., manually or via a motor). 
     Slot  58  extends circumferentially around transfer set holder  52   b  allowing the gear train to rotate holder  52   b , while or after peg  78   b  translates holder  58   b . When peg  78   b  pulls transfer set holder towards gear  42 , slots  54  of transfer set holder  52   b  come free from pegs  78   a  of lower portion  68  and lid  66 , allowing transfer set holder  52   b  to be rotated. 
     Device gear  44  connected to transfer set holder  52   b  is likewise split along centerline C L , creating an upper portion  44   a  of gear  44  connected to upper half  74  of transfer set holder  52   b  and a lower portion  44   b  of gear  44  connected to lower half  76  of transfer set holder  52   b . Portions  44   a  and  44   b  operate together when upper half  74  and lower half  76  of transfer set holder  52   b  are positioned together (when lid  66  of housing  64  is closed onto lower portion  68  of housing  64 ). 
     When driving peg  78   b  pulls lower half  76  connected to upper half  74  of transfer set holder  52   b  fully away from stationary port holder  52   a , the connectors become uncapped, and gear  44  (mated halves  44   a  and  44   b ) comes into operable engagement with gear  42  as described above. The gear train driving gear  42  can thereafter rotate transfer set holder  52   b  relative to port holder  52   a . After being rotated, e.g., one-hundred-eighty degrees, driving peg  78   b  pushes transfer set holder  52   b  (now at half  74 ), such that slots  54  of transfer set holder  52   b  reengage with pegs  78   a , and the connectors of transfer set holder  52   b  reengage with fixed port holder  52   a.    
     Transfer set holder  52   b  holds a spike connector  80  and a male plug  86 , shown in  FIGS. 3 to 13 . When driving peg  78   b  pushes transfer set holder  52   b  back into engagement with fixed port holder  52   a , device  50  in one embodiment mates spike connector  80  (patient) connector with port connector  90  (supply connector) and male plug  86  with female plug  96  shown below in  FIGS. 3 to 13 . When the supply bag connected to connector  90  is emptied, transfer set holder is again moved away from port holder  82   a . Holder  52   b  is translated so that the rotational gears mesh, the gear train rotates holder  52   b  again one-hundred-eight degrees, and holder  52   b  is pushed back to holder  52   a , putting the caps back onto the connectors. As discussed below, during rotation of device  50 , light applicator sterilizes the connectors. 
     An optional slide holder  52   c  in one embodiment holds male plug  86  (transfer set holder  52   b  holds spike connector  80 ). Slide holder  52   c  slides back and forth relative to transfer set holder  52   b  and port holder  52   a  and provides an additional degree of movement freedom if needed, as shown below. It should be noted that the drive train of  FIG. 1  is for when slide holder  52   c  is not provided. If slide holder  52   c  is provided, it can be driven via a driving peg  78   b  as discussed above of transfer set holder  52   b.    
       FIGS. 3 to 6  illustrates the disconnection/reconnection sequence from above, e.g., with lid  66  has removed to aid illustration. Lower portion  68  of housing is seen however.  FIG. 3  shows an embodiment of device  50  in a state in which both connectors  80  and  90  are secured at their connecting ends to a mating plug  96  and  86 , respectively.  FIG. 4  shows that transfer set holder  52   b  is slid away from port holder  52   a , e.g., from the position shown in  FIG. 3 , which pulls a spike  84  of patient connector  80  out of female plug  96  and pulls male plug  86  away from port connector  90 . In an alternative embodiment, slide holder  52   c  holding plug  86  is provided and is also translated away from port connector  52   a  for additional clearance, which can be seen by the relative difference in distance of the connection end of plug  86  and spike  84  between  FIGS. 3 and 4 . 
     In  FIG. 5 , transfer set holder  52   b  is rotated relative to the light applicator housing such that plug  86  is now aligned with plug  96  and patient connector  80  is aligned with port connector  90 . At this point in the process, a light activator  70  (located above and below spike  84  of patient connector  80  in one embodiment but alternatively additionally above and below supply connector  90 ) in lid  66  and lower portion  68  of housing  64  is energized to irradiate any one, or more, or all of the exposed surfaces, namely spike  84  of connector  80 , diaphragm  94  of connector  90  if still connected to the connector, inner surfaces of connector  80  and  90 , inner and outer surfaces of plugs  86  and  96  and any other needed surface of connectors  80  and  90  and plugs  86  and  96 . Light applicator  70  can be energized manually or automatically. As discussed in the incorporated patents and application, the irradiation can last for approximately a minute, for example, or be controlled by measuring energy imparted to the connectors. 
     In  FIG. 6 , transfer set holder  52   b  is translated toward port holder  52   a , such that plugs  86  and  96  are mated and spike connector  84  of patient connector  80  spikes through diaphragm  94  of port connector  90  to enable fluid from a supply bag to flow (directly or via a disposable cassette) through connector  90 , connector  80 , the patient&#39;s transfer set, the patient&#39;s indwelling catheter and into the patient&#39;s peritoneum. A like connection is made to enable fluid to flow from the patient&#39;s peritoneum through patient connector  80 , a drain connector similar to supply connector  90 , which carries the spent fluid to a drain or drain bag. Although not illustrated expressly in  FIG. 6 , slide holder  52   c  holding plug  86  is translated again automatically to connect plug  86  to plug  96 , which can be seen for example by the difference in relative positioning of plug  86  and the box representing transfer set holder  52   b  between  FIGS. 5 and 6 . 
     To disconnect the patient connector  80  from supply connector  90 , the steps shown in  FIGS. 3 to 6  are performed in reverse, here, from  FIG. 6  to  FIG. 3 . UV applicator  70  is again energized in reverse  FIG. 5 , the second step in disconnection, after connector  80  is removed from connector  90  and plug  86  is removed from plug  96 . In this manner, the connectors and plugs are again disinfected before disconnection is completed via rotation in reverse  FIG. 4  and reconnection of the connectors to the respective plugs in reverse  FIG. 3 . 
     Referring now to  FIGS. 7 to 13 , the disconnection sequence just described is shown schematically. It should be appreciated that the connection sequence just shown in  FIGS. 3 to 6  is also illustrated by  FIGS. 7 to 13 , only the sequence in  FIGS. 7 to 13  occur in reverse. The reason for two additional figures is that the separate translations of slide holder  52   c  to transfer set holder  52   b  and of transfer set holder  52   b  relatively to port holder  52   a  are broken out here in separate steps in  FIGS. 8 and 9  and  FIGS. 11 and 12 . 
       FIGS. 7 to 13  also illustrate the use of a valve  60  to open and close supply line  92 . Valve  60  can be opened and closed automatically, e.g., via automatically actuated occluder halves  22  and  24  shown and described above. Alternatively, valve  60  is operated manually. In  FIGS. 7 to 13 , valve  60  is shown as being part port holder  52   a . It is contemplated to provide valve  60  as a manually or automatically actuated valve within port holder  52   a . Alternatively, valve  60  can be a line clamp on supply line  92 . Further alternatively, valve  60  is integrated with an APD cycler, which closes and opens supply line  92  automatically. In  FIG. 1 , valve  60  is formed via occluder halves  22  and  24  and is located on occluder subassembly  20  of system  10 . 
     In  FIG. 7 , valve  60  is closed such that fluid cannot flow from supply line  92  to patient line  82  or flow from the patient through patient line  82 , to a drain line. Patient connector  80  is connected sealingly to port connector  90 . Slide holder  52   c  is fully advanced towards port holder  52   a  and thus plug  86  carried by slide holder  52   c  is mated with plug  96  held by port holder  52   a.    
     In  FIG. 8 , clamp  60  remains closed. A motor (not illustrated) drives a slide holder actuator  62 , in a manner similar above for transfer set holder  52   b , to pull slide holder  52   c  and port  86  held by slide holder  82   c  away from port holder  52   a . This action causes plug  86  to disconnect from plug  96  held by port holder  52   a . Alternatively, slide holder  52   c  is not used and this step is skipped. 
     In  FIG. 9 , valve  60  remains closed. Here, the transfer set holder  52   b  is pulled translationally away from port holder  52   a . This action pulls plugs  86  and  96  apart further. Moreover, the action causes spike  84  of patient connector  80  to become disconnected from port connector  90 . 
     In  FIG. 10 , valve  60  remains closed and transfer set holder  52   b  is rotated one-hundred-eighty degrees relative to port holder  52   a , so that plug  86  and slide holder  52   c  are now aligned with port connector  90 , while patient connector  80  is aligned with plug  96 . In this step, UV applicator  70  provides sufficient energy over time to effectively disinfect pertinent portions of the connectors and plugs, such as the spike and sealing area of patient connector  80 , the sealing area of port connector  90 , and the sealing areas of plugs  86  and  96 . 
       FIG. 11  illustrates a first translational motion in the reconnection of transfer set holder  52   b  to port holder  52   a . Here, the entire transfer set holder  52   b  is translated inward towards port holder  52   a . Valve  60  remains closed. This action causes spike  84  and sealing area of patient connector  80  to mate with the sealing area of plug  96 . 
     In  FIG. 12  valve  60  remains closed, a motor translates actuator  62 , slide holder  52   c  and plug  86  carried by slide holder  52   c  relative to transfer set holder  52   b  and port holder  52   a  such that plug  86  mates with and seals to port connector  90 . In  FIG. 13 , valve  60  is opened allowing any fluid trapped upstream of the valve to flow to drain from the system or to allow new fresh solution to be delivered via supply line  92 . 
     Upon reconnecting connectors  80  and  90 , a first step as in  FIG. 7  is to close valve  60 . In reconnection, after the transfer set holder is rotated, the UV flash  70  is energized, and reconnection of the connectors takes place, valve  60  is opened, like in  FIG. 13 , to allow fluid to flow through the connectors. 
     Referring now to  FIG. 14 , a temporary transfer set disconnect/reconnect feature is illustrated. Connection/disconnection device  50  allows patient connector  80  and plug  96  to be removed together from transfer set holder  52   b  and port holder  52   a , respectively, e.g., by rotating lid  64  from lower portion  66  of housing  62 , thereby rotating upper portion  74  of drum device  10  from lower portion  76  of device  50 , exposing connected patient connector  80  and plug  96 . The patient may do this for a number of reasons, for example, to halt therapy for a time so that the patient can conduct other business, e.g., to go to the bathroom, before returning to reinitiate therapy. 
     When the patient returns, the patient opens lid  64  from lower portion  66  of housing  62 , thereby rotating upper portion  74  of drum device  50  from lower portion  76  of device  50 , exposing the holding portions of lower portion  76  of device  50 . The patient reinserts patient connector  80  and plug  96  into transfer set holder  52   b  and port holder  52   a , respectively, and closes lid  62  to allow treatment to proceed. 
     Afterwards, clamp or valve  60  is closed. Next, transfer set holder  52   b  and slide holder  52   c  are translated away from port holder  52   a  to disconnect patient connector  80  from plug  96  and plug  86  from port connector  90 . Next, transfer set holder  52   b  is rotated, such that patient connector  80  is aligned with port connector  90 . UV applicator  70  irradiates the connectors and plugs to disinfect these components. Next, transfer set holder  52   b  and slide holder  52   c  are translated towards port connector  52   a , connecting connector  80  to connector  90  and mating plugs  86  and  96 . Valve or clamp  60  is then opened to allow dialysis fluid flow through the system. 
     Connector Improvements 
     Referring now to  FIGS. 15 to 17 , an embodiment for supply or port connector  90  is illustrated. Port connector  90  is made of a suitable medical grade material, such as polyvinylchloride (“PVC”) or polypropylene (“PP”). Port connector  90  includes a tube holding or tube sealing portion  104 , a flange portion  102  and a shroud portion  100 . Tube portion  104  is sized to fit snuggly within a tube, which can be semi-permanently or permanently fixed to tube portion  104 . As discussed below in connection with  FIGS. 20 and 21 , tube connecting portion  104  in an embodiment includes one or more barbed ring (not illustrated here). Flange portion  102  is sized to fit within port connector  52   a  of connection/disconnection device  50  as illustrated below in connection with  FIG. 19 . 
     As seen in  FIG. 15 , shroud  100  is sized and shaped so as to prevent a person&#39;s finger from contacting a radially extending wall  106  at the base of shroud  100  and from contacting an inner, annular surface  108  of port connector  90 . Radial wall  106  and inner annular surface  108  are primary areas of concern for contamination. These areas contact the spike  84  of patient connector  80  as seen in  FIGS. 16 and 17 . Preventing a person from touching radial wall  106  and inner annular surface  108  prevents those areas from becoming infected in the first place (e.g., upon temporary removal from device  50 ) and accordingly reduces the bacterial load on UV applicator  70  described above. 
     Shroud  100  includes a cylindrical wall  110 , which extends longitudinally away from radial wall  106  a distance sufficient to ensure that the patient&#39;s finger does not touch radial wall  106  or inner annular surface  108 . An inner diameter of cylindrical wall  110  is sized to seal to or press-fit to a sealing portion  88  of patient connector  80 . This is a secondary seal to a primary seal made between spike  84  and inner wall  108  of connector  90 . 
     As seen in  FIG. 16 , wall  110  protects sealing portion  88  and an inner surface of wall  110  close to the edge of the wall, while patient connector  80  is connected to supply connector  90 . Also, wall  110  prevents secondary sealing portion  88  from touching and potentially transmitting contamination to radial wall  106  of port connector  90 . Further, UV applicator  70  can irradiate and destroy any contamination that does appear on sealing portion  88 . 
     Referring now to  FIG. 19 , an additional benefit of port connector  90  is illustrated. Connector  90  is shown mounted in port holder portion  52   a  of connection/disconnection device  50  or other port holder. Here, flange  102  of port connector  90  is spaced apart from shroud  100  a distance sufficient to enable shroud  100  to reside past the edge of port holder  52   a  or other port holder. When port connector  90  is loaded initially into port holder  52   a  (or other port holder), the mating end of connector  90  is protected via a tip protector  120 . The configuration of connector  90  and port holder  52   a  (or other port holder) enables connector  90  with tip protector  120  attached to be loaded into port holder  52   a  (or other port holder) before having to remove tip protector  120 . This enables the patient once connector  90  is loaded into port holder  52   a  (or other port holder) to grasp connection device  50  (or other connection device) to remove tip protector  120  as opposed to holding connector  90  directly to remove the tip protector. This feature further isolates connector  90  from human touch and further lessens the likelihood that connector  90  will become contaminated in the first place. 
     Referring now to  FIGS. 18 and 19 , an embodiment for patient connector or male connector  80  is illustrated.  FIG. 19  shows a section of connector  80  taken along line XVIX-XVIX of  FIG. 18 . Patient connector  80  can be made of any of the materials discussed above for supply connector  90 . For reference, patient connector  80  includes a spike tip  84 , a sealing area  88 , a flange portion  89 , which in the illustrated embodiment is threaded. The threaded flange portion  89  threads onto a mating portion of an overall transfer set assembly, which is sometimes referred to as a flow control barrel. The patient connector  80  also includes a tube sealing area  112 , which receives patient tube  82  described above in connection with  FIGS. 16 to 18 . 
     In the illustrated embodiment, sealing portion  112  includes a plurality of barbed rings or projections  114  and  116 . Barbed rings  114  and  116  include a surface angled so that a length of tube  82  can slide over tube sealing portion  112  relatively easily. In an embodiment, the angle of the surface is about thirty degrees although other angles could be used. Thirty degrees offers enough barb height for bite into mating tube  82  without the barb becoming too long. Thirty degrees also facilitates easy assembly. 
     In the illustrated embodiment, barbed rings  114  and  116  are spaced apart about 0.3 inch (7.62 mm) The outer diameter of barbed ring is 0.250 inch (6.35 mm), extending from the surface of sealing portion  112 , which has an outer diameter of 0.220 inch (5.59 mm) 
     Threaded flange portion is spaced apart from the end of sealing area  112  a distance of 0.577 in (14.7 mm) in one implementation. Thus, barbed rings  114  and  116  in one embodiment are spaced apart by a distance at least as large as the inner diameter of sealing portion  112 . The length of sealing portion  112  is at least two times the outer diameter of sealing portion  112  in the illustrated embodiment. Further, if tube  82  attached to connector  80  has an outer diameter of 0.250 inch (6.35 mm), then the height of the barb off of the surface of portion  112  can be less than or equal to a thickness of tube  82 . These dimensions help secure a proper and easily made seal between connector  80  and tube  82 . 
     While barbed rings  114  and  116  enable tube  82  to be positioned over sealing section  112  relatively easily, the barbed rings provide a tube removal force greater than a desired 5 lbs. In tests performed on a spike connector  80  having barbed rings  114  and  116 , a mean pull of force of  10 . 6  lbs was measured, with a standard deviation of 0.2 lbs. Thus, even after remaining three times the standard deviation less the mean pull force of 10.6 lbs, the measured pull-off force is greater than the 5 lbs desired pull-off force. 
     Referring now to  FIGS. 20 and 21  ( FIG. 21  is a sectioned view of connector  80  taken along line XXI-XXI of  FIG. 20 , and which shows mated port connector  90  in cross-section), another embodiment for patient connector or male connector  80  and port connector  90  is illustrated. Each of the teachings in connection with  FIGS. 15 to 21  is applicable also to the embodiments of  FIGS. 20 and 21  and vice versa. In  FIGS. 20 and 21 , sealing portion  88  of spike connector  80  includes outwardly extending rings  120  and  122 , which define in between an annular groove  124 . Shroud or port  100  of connector  90  defines or includes an undercut geometry or inwardly extending projection  126 , which snap-fits or frictionally fits into annular groove  124  of connector  80 . In an alternative embodiment, shroud or port  100  of connector  90  defines an annular groove, while sealing portion  88  of connector  80  includes or defines an outwardly projecting ring that snap-fits or frictionally fits into the alternative annular groove shroud or port  100 . 
     The snap-fitting or frictional relationship just described enables spike connector  80  to have a frictional engaging portion  128  and a stepped-down portion  130 . Frictional engaging portion  128  engages an inner annular surface portion  132  of port connector  90 . Stepped-down portion  128  of spike  84  produces an inner, annular surface portion  134  of connector  90  at which spike  84  does not contact the connector  90 . Reducing the contact area of spike  84  with inner, annular surface portion  132  of connector  90  reduces the overall connection and disconnection force required to insert spike connector  80  into port connector  90 . 
     Also, because the connector set of  FIGS. 20 and 21  does not require all of spike  84  to seal to the inner annular surface of connector  90 , the geometry of the tip portion of spike  84  can be optimized to suit other performance characteristics, such as desired connection and disconnection force as provided here via stepped-down portion  130  of spike  84  or a puncturing optimization of spike  84 , for example. 
     It should be understood that various changes and modifications to the presently preferred embodiments described herein will be apparent to those skilled in the art. Such changes and modifications can be made without departing from the spirit and scope of the present subject matter and without diminishing its intended advantages. It is therefore intended that such changes and modifications be covered by the appended claims.