Abstract:
A dialysis system includes a source of effluent dialysis fluid, a drain container configured to receive the effluent dialysis fluid through a drain tube, and a load cell. The drain container includes an at least semi-rigid body defining a first key feature. The load cell includes a second, mating key feature positioned and arranged to mate with the first key feature.

Description:
PRIORITY 
       [0001]    This application claims priority to and the benefit as a continuation application of U.S. patent application Ser. No. 12/016,769, filed Jan. 18, 2008, entitled, “Reusable Effluent Drain Container for Dialysis and Other Medical Fluid Therapies”, the entire contents of which is incorporated herein by reference and relied upon. 
     
    
     BACKGROUND 
       [0002]    The examples discussed below relate generally to medical fluid delivery. More particularly, the examples disclose systems, methods and apparatuses for dialysis such as hemodialysis (“HD”) and automated peritoneal dialysis (“APD”). 
         [0003]    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. 
         [0004]    Kidney failure and reduced kidney function have been treated with dialysis. Dialysis removes waste, toxins and excess water from the body that normal functioning kidneys would otherwise remove. Dialysis treatment for replacement of kidney functions is critical to many people because the treatment is life saving. 
         [0005]    One type of kidney failure therapy is peritoneal dialysis, which infuses a dialysis solution, also called dialysate, 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. 
         [0006]    There are various types of peritoneal dialysis therapies, including continuous ambulatory peritoneal dialysis (“CAPD”), automated peritoneal dialysis (“APD”), tidal flow dialysis and continuous flow peritoneal dialysis (“CFPD”). CAPD is a manual dialysis treatment. Here, the patient manually connects an implanted catheter to a drain, allowing spent dialysate fluid to drain from the peritoneal cavity. The patient then connects the catheter to a bag of fresh dialysate, infusing fresh dialysate through the catheter and into the patient. The patient disconnects the catheter from the fresh dialysate bag and allows the dialysate to dwell within the peritoneal cavity, wherein the transfer of waste, toxins and excess water takes place. After a dwell period, the patient repeats the manual dialysis procedure, for example, four times per day, each treatment lasting about an hour. Manual peritoneal dialysis requires a significant amount of time and effort from the patient, leaving ample room for improvement. 
         [0007]    Automated peritoneal dialysis (“APD”) is similar to CAPD in that the dialysis treatment includes drain, fill, and dwell cycles. APD machines, 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 for the dialysate to dwell within the cavity and for the transfer of waste, toxins and excess water to take place. The source can be multiple sterile dialysate solution bags. 
         [0008]    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 dialysis. A “last fill” occurs at the end of APD, which remains in the peritoneal cavity of the patient until the next treatment. 
         [0009]    Regardless of the type of dialysis performed, the dialysis treatment will produce waste or effluent dialysis fluid, which is also referred to as drain fluid or “spent” dialysate. Spent dialysate can be sent to various places within the patient&#39;s home, such as the patient&#39;s bathtub or toilet. Alternatively, the effluent dialysate is sent to a drain bag. Both alternatives have disadvantages. Delivering spent dialysate to the patient&#39;s bathtub or toilet can require that long runs of tubing, which adds cost and can be a nuisance especially if the room in which therapy is performed is not close to a house drain. The drain areas of the house can also carry a large bioburden, which can be detrimental to a patient who is about to perform a sterile dialysis therapy. Drain bags collecting an entire treatment&#39;s worth of spent fluid can become heavy and difficult to move, especially for elderly patients. Drain bags are also disposable, adding to per therapy cost. The embodiments discussed herein attempt to address these disadvantages. 
       SUMMARY 
       [0010]    The present disclosure provides a reusable drain container, which is easy to connect to, move and remove fluid from a medical fluid therapy system, such as a dialysis system. The container is rigid or semi-rigid, which aids in its transport. The container is sized to hold an entire therapy&#39;s worth of spent or effluent fluid. The container in one embodiment includes a front side and a back side opposite the front side. The container includes a top surface and a bottom surface. The container also includes two sides, forming a generally rectangular enclosure, although it is contemplated to make one or more of the sides more or less rounded. The container in various embodiments is made of plastic, composites, aluminum and combinations thereof. 
         [0011]    The container is operable with any type of dialysis treatment that produces waster or effluent dialysate, such as any type of peritoneal dialysis treatment and any type of blood cleaning dialysis treatment. In the embodiments discussed below, the container is shown in connection with a peritoneal dialysis system, and in particular with an APD system using a weigh scale control of fluid fresh dialysate delivered to the patient and spent dialysate and ultrafiltrate (“UF”) removed from the patient. It should be appreciated however that many of the teachings associated with the drain container are applicable to any type of dialysis treatment and to any type of dialysate and UF control. 
         [0012]    With the weigh system, the container in one embodiment sits on a load cell during treatment such that the front of the container points upwardly and the back of the container rests on the load cell. A spent fluid inlet and spent fluid outlet are both provided on the front of the container, such that during treatment both the spent fluid inlet and spent fluid outlet point upwardly towards the dialysis instrument (which is located above the drain container in one implementation). The spent fluid inlet is therefore readily accessed. The spent fluid inlet and outlet are maintained elevationally above the drain fluid collected in the drain container during therapy, preventing leakage of the effluent fluid from the inlet or outlet. 
         [0013]    In one embodiment, the back of the container, which rests on the load cell during treatment, includes a key feature, which mates with a key feature associated with the load cell. The mating key features prevent the patient from incorrectly loading the container onto the load cell, which can be important for proper operation of the load cell system. The mating key features also tend to hold the container in place when subjected to inadvertent bumping or forces. The mating key features further tend to prevent misuse with a generic container or bucket. 
         [0014]    The container in one embodiment includes wheels for transporting the container from the dialysis instrument to a house drain, e.g., sink, toilet, shower, bathtub or floor drain. The load cell includes wheel tracks. When therapy is complete, the patient tilts the container such that the key feature of the container lifts free from the key feature of the load cell. The patient then rolls the container along the tracks off of the, e.g., slanted, load cell, onto the ground, and to the house drain. 
         [0015]    When the container is lifted from the load cell, it is tilted such that the top of the container, which includes a handle, points upwardly and is accessible. The spent fluid outlet, located towards the bottom of the container on the front side of the container is positioned near the ground. 
         [0016]    The wheels can be connected directly to the container or to an assembly to which the container is removeably attached. The wheel assembly can have a telescoping handle, which the patient can pull away from the container so that the patient does not have to bend over to pull the container to the house drain. The telescoping handle can be provided in addition to or in place of a handle formed integrally with the container. 
         [0017]    The container also includes a number of helpful features for the removal of effluent from the container to drain once the patient has wheeled the container from the dialysis instrument to the house drain. For example, the container in one embodiment includes an indent or groove that holds the container in place on the rim of a toilet, or bathtub, which allows for hands free removal of a cap from the spent fluid outlet. Also, the container includes a spout, which is exposed once the cap is removed. The spout directs effluent fluid from the container into the house drain in a smooth manner to reduce splashing and spilling. The spout is removable from the container in one implementation for cleaning purposes. 
         [0018]    The container also includes features for viewing and sampling the effluent or spent dialysate. For example, the front or top of the container can have one or more window for viewing the drained liquid within the container. Alternatively, one or more of the spent fluid inlet or spent fluid outlet caps can be clear or transparent for viewing effluent within the container. Still further, the container can be sealed together from separate pieces, one or more of which is clear or transparent for viewing the color and consistency of the effluent fluid. In any case, viewing effluent is important because a certain color effluent can indicate that the patient is on the verge of suffering from peritonitis. To this end, it is contemplated to provide printed text and/or colored surfaces, which aid the patient in determining if the effluent is cloudy (onset of peritonitis). 
         [0019]    The container in one embodiment also includes a sample reservoir, which automatically fills with fluid, and which can be removed from the container, so that the patient can take the sample to a dialysis center or other qualified facility for analysis. The reservoir in one embodiment traps the fluid sample and allows it to be removed from the container without having to pour out a sample. 
         [0020]    It is also contemplated to size one of the inlet and outlet caps so as to hold an appropriate amount of a cleanser, e.g., bleach, which is used to clean and disinfect the container after a number of uses. For example, the spent fluid outlet cap can be sized for such use, while the spent fluid inlet cap is provided with a tubing port configured to accept and seal to a drain tube running from the dialysis instrument to the container. 
         [0021]    It is therefore an advantage of the present disclosure to provide a reusable medical fluid drain container. 
         [0022]    It is another advantage of the present disclosure to provide a drain container that is transported readily from the dialysis instrument to a house drain, reducing the amount of tubing needed to run directly from the instrument to the house drain. 
         [0023]    It is a further advantage of the present disclosure to provide a draining system, which provides a ready apparatus for taking effluent samples. 
         [0024]    It is yet another advantage of the present disclosure to provide a dialysis drain container, which provides a ready apparatus for viewing effluent dialysate to detect onset of peritonitis. 
         [0025]    Additional features and advantages are described herein, and will be apparent from, the following Detailed Description and the figures. 
     
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         [0026]      FIG. 1  is a perspective view of a medical fluid delivery system operating with one embodiment of the drain container of the present disclosure. 
           [0027]      FIG. 2  is a perspective view of one embodiment of a drain container of the present disclosure. 
           [0028]      FIG. 3  is a front view of the drain container of  FIG. 2 . 
           [0029]      FIG. 4  is a rear view of the drain container of  FIG. 2 . 
           [0030]      FIG. 5  is a side view of the drain container of  FIG. 2 . 
           [0031]      FIG. 6  is a perspective view of one embodiment of an inlet cap useable with the drain container of  FIG. 1 . 
           [0032]      FIG. 7  is a top plan view of the inlet cap of  FIG. 6 . 
           [0033]      FIG. 8  is a sectioned elevation view taken along line VIII-VIII of  FIG. 7 . 
           [0034]      FIG. 9  is a sectioned elevation view taken at detail IX of  FIG. 8 . 
           [0035]      FIG. 10  is a perspective view of one embodiment of a spout useable with the drain container of  FIG. 1 . 
           [0036]      FIG. 11  is a perspective view of one embodiment of a sample reservoir useable with the drain container of  FIG. 1 . 
           [0037]      FIG. 12  is a sectioned elevation view of the sample reservoir of  FIG. 11 . 
           [0038]      FIG. 13  is a sectioned elevation view of one embodiment of a tube stop useable with the drain container of  FIG. 1 . 
           [0039]      FIG. 14  is a perspective view of another embodiment of a drain container of the present disclosure. 
           [0040]      FIG. 15  is a perspective view of one embodiment of a sample reservoir useable with the drain container of  FIG. 14 . 
           [0041]      FIG. 16  is a perspective view of a further embodiment of a drain container of the present disclosure having a further alternative fluid reservoir. 
           [0042]      FIG. 17  is a side view of a telescoping wheel assembly useable with any of the drain containers discussed herein. 
           [0043]      FIG. 18  is a perspective view of one embodiment of a load cell useable with any of the drain containers discussed herein. 
       
    
    
     DETAILED DESCRIPTION 
       [0044]    Referring now to the drawings and in particular to  FIG. 1 , system  10  illustrates a medical fluid system, such as a dialysis system, that can use the various drain containers discussed herein. While the drain containers can be used with other types of medical fluid treatments, dialysis and in particular peritoneal dialysis provides one particularly well suited application. System  10  in the illustrated embodiment is an automated peritoneal dialysis (“APD”) system. Various techniques have been developed to monitor the amount of dialys ate delivered and removed from the patient as well as amount of the patient&#39;s body fluid or ultrafiltrate, which is also removed from the patient undergoing APD. In the illustrated embodiment, system  10  operates with a load cell  12 . The load cell is discussed in more detail below in connection with  FIG. 18 . It should be appreciated however that the drain containers discussed herein can operate with APD systems having volumetric control systems other than load cells. Further, the drain containers discussed herein can operate with other types of peritoneal dialysis than APD, such as continuous ambulatory peritoneal dialysis (“CAPD”), which is generally considered to be a manual form of PD. 
         [0045]    System  10  also includes an instrument  20 , which includes a control panel  22  allowing the operator or patient to set, begin and monitor treatment. Instrument  20  also includes valve and pump actuators that operate with disposable fluid tubes to distribute medical fluid, such as dialysate to a desired destination. Instrument  20  in one embodiment operates with pinch valves that pinch various parts of a tubing set to control the flow of fresh and spent dialysate to a desired destination. Alternatively, instrument  20  operates a disposable cassette, which can include cassette sheating that is selectively closed against or opened from rigid valves at various places to produce a desired valve state. Instrument  20  can include a plurality of pumps for pumping dialysis fluid to and from a patient or dialyzer. 
         [0046]    In the illustrated embodiment, the instrument uses a pump or gravity to feed fresh fluid from a supply bag  14  to the patient through a patient line  16  and uses a pump or gravity to feed spent or effluent fluid from the patient to a drain container  50  via a pump (not illustrated) located within instrument  20  via a drain line  18 . Supply bags  14  are located on a heater  30 , which can be a resistive heater. Heater  30  heats dialysate to a desirable temperature for treatment, such as 37° C. Fluid flows from supply bags  14  and heater  30  via a pump or gravity through a supply line  24  from each supply bag  14  to instrument  20 . When certain one or more valve is open, the heated fluid from supply line  24  flows through the disposable including patient line  16  to the patient. 
         [0047]    As discussed above, the amount of effluent fluid flowing from the patient to drain container  50  through drain line  18  is weighed at load cell  12 . That weight can be compared against a known weight of supply bags  14  to determine an amount of ultrafiltrate (“UF”) that has been removed from the patient. Alternatively, instrument  20  can include a weigh scale that weighs the amount of fresh fluid contained in supply bags  14 . Here, a controller within instrument  20  subtracts the beginning weight of fluid in supply bags  14  from the weight of fluid collected in container  50  to determine the amount of UF removed from the patient. 
         [0048]    System  10  also includes a stand  26 , which is connected to a wheeled base  28 , which allows system  10  to be moved within the patient&#39;s house or within a center or hospital. One system and method for operating system  10  is discussed in copending patent applications entitled: “Automated Dialysis System Driven By Gravity And Vacuum”, filed May 26, 2006, Ser. No. 11/420,608, the entire contents of which are incorporated herein expressly by reference and relied upon. 
         [0049]    Referring now to  FIGS. 2 to 5 , container  50   a  illustrates one embodiment of a drain container of the present disclosure. Container  50   a  includes a front side  52 , rear side  54 , top surface  56  and bottom surface  58 . In  FIG. 1 , container  50  is shown such that its front surface  52  points upwardly towards dialysis instrument  20 . This configuration is advantageous because the drain fluid inlet and drain fluid outlet are provided on front surface  52  and are accordingly pointed towards dialysis instrument  20  and located elevationally above the drain fluid as the fluid fills within container  50  during operation. As shown below, when it is time to roll drain container  50  to a place to remove fluid from the container, the container is tilted such that top surface  56  points upwardly, and so that the patient can grab a handle  60  located at top surface  56 . In one embodiment, drain container  50   a  is plastic, such as polypropylene (“PP”), high density polyethylene (“HDPE”), low density Polyethylene (“LDPE”), polycarbonate (“PC”), glycol-modified polyethylene terephthalate (“PET-G”), polyvinyl chloride (“PVC”); a composite material; aluminum and combinations thereof. Drain container  50   a  in one embodiment has a wall thickness, which is generally uniform, and which can be from about 1 mm to about 7 mm, e.g., 4 mm Container  50   a  defines an internal volume that is sized for the particular medical fluid application. For dialysis treatment, such as peritoneal dialysis treatment, container  50   a  is sized to hold an entire treatment&#39;s worth of drain fluid. Container  52   a  can therefore be configured to hold from about five to about forty liters, e.g., eighteen liters, of effluent fluid. 
         [0050]    As discussed above, front surface  52  of container  50   a  includes or defines a spent fluid inlet  62  and a spent fluid outlet  64 . Inlet  62  and outlet  64  in one embodiment are threaded ports that matingly receive threaded caps as discussed in detail below. Spent fluid outlet  64  is located near bottom surface  58 , so that when the patient or caregiver pulls drain container  50   a  to a toilet, tub or house drain, outlet  64  will be located elevationally below handle  60 , so that the patient or caregiver can readily drain effluent fluid from drain container  50   a . Spent fluid inlet  62  is located closer to top  56  of container  50   a , such that when the patient or caregiver tilts drain container  50   a  using handle  60 , inlet  62  is likewise raised elevationally, allowing the patient to more readily remove drain line  18  from the inlet cap (shown below). The patient or caregiver can thereafter pull drain container  50   a  to a house drain. 
         [0051]    As seen in  FIGS. 2 and 5 , bottom  58  of drain container  50   a  includes or defines a slot or groove  66 , which is sized and shaped to snap-fit over an axle of a wheel assembly. One suitable wheel assembly is discussed below in connection with  FIG. 17 .  FIGS. 2 and 5  also illustrate that side surfaces  92  of drain container  50   a  include or define grooves or slots  94  that mate with a frame of the wheeled assembly, such as the assembly shown below in connection with  FIG. 17 . In one embodiment drain container  50   a  is removable from the wheel assembly via snap-fitting slot or groove  66 . Although not illustrated, bottom  58  of drain container  50   a  in one embodiment also includes apparatus configured to hold the drain container in place when the drain container is placed on a toilet or bathtub to drain from outlet  64  to the toilet or bathtub. 
         [0052]      FIGS. 2 and 4  also show that rear surface  54  includes or defines an indented or female key structure  68 . Indented key structure  50  is sized and configured to mate with a corresponding projecting or male key structure on the load cell when drain container  50   a  is placed in position for treatment. The keyed interfaced between drain container  50   a  and load cell is discussed in detail below in connection with  FIG. 18 . 
         [0053]    Referring now to  FIGS. 6 to 9 , cap  70  illustrates one embodiment of a spent fluid inlet cap, which is suitable for use with container  50   a  of  FIGS. 2 to 5 . Inlet cap  70  can be made of certain of the materials specified above for drain container  50   a , such as, PC, PET-G, PVC and polycarbonate polyester blend, which can each be clear for cap  70 , which is clear in one embodiment. Cap  70  can have a nominal wall thickness of about 1 mm to about 7 mm, e.g., about 4 mm. Cap  70  in an embodiment is sized to thread onto spent fluid inlet  62  of drain container  50   a , as seen best in  FIGS. 3 and 5 . While cap  70  is shown being configured to mate with inlet  62  via a threaded relationship, it should be appreciated that cap  70  could fit sealingly to inlet  62  via a snap-fitting and/or hinged manner. 
         [0054]      FIG. 8  illustrates cap  70  having internal threads  72  that mate with external threads of inlet  62  of drain container  50   a . Cap  70  further defines a drain tube opening  74 . As seen most clearly in  FIGS. 8 and 9 , drain tube opening  74  tapers at flared annular wall  76  to form a drain tube  18  accepting area. Flared annular wall  76  extends inward to a port  78 , which includes inner and outer cylindrical extensions  78   a  and  78   b , respectively. Drain line  18  is inserted into the inlet cap  70  through splices  78   c , through extension  78   b  and then into the tube stop  110  shown in  FIG. 13 , which is fitted to outer cylindrical extensions  78 . The inner diameter (e.g., 18 mm−2*thickness of wall  114 ) of tube stop larger diameter portion  114  is solvent bonded or otherwise adhered to the outside of outer cylindrical extensions  78   a  (e.g., 15.6 mm OD). After passing through splices  78   c  and extension  78   b , the tubing seals against the inner diameter of smaller diameter portion  112  of the tube stop  110  of  FIG. 13  and bottoms out against cap  116  of tube stop  110 . 
         [0055]    Referring now to  FIG. 10 , spout  80  illustrates one suitable spout for operation with drain container  50   a . Spout  80  can be made of any of the material specified above for drain container  80 . Spout  80  can have a nominal wall thickness of about 2 mm to about 7 mm. In the present embodiment, spout  80  is configured to fit sealingly into outlet  64  of drain container  50   a . Spout  80  includes a basin portion  82 , which is sized to collect any effluent that may spill out of a funnel portion  84  during the effluent fluid removal process. Basin  82  also defines an opening  86 , which allows air to enter drain container  50   a  while effluent fluid is poured smoothly out of funnel  84  of spout  80 . 
         [0056]    Basin  82  extends upward to a rim  88 , which has a larger diameter than basin  82 . Rim  88  is sized to press-fit to an inner wall of spent fluid outlet  64  of drain container  50   a  in such a manner that outwardly extending threads of spent fluid outlet  64  (in one embodiment) are left free to be threaded to an outlet cap, which is inserted over spout. Rim  80  includes or defines one or more locking aperture or projection  90 , which locks to a mating projection or aperture, respectively, of the inlet wall of spent fluid outlet  64  when spout  80  is press-fit to drain container  50   a . Projection or aperture  90  locks spout  80  in place with drain container  50   a  and prevents spout  80  from being pushed into the drain fluid collecting chamber of container  50   a.    
         [0057]    It should be appreciated that spout  80  can be formed integrally with container  50   a  in an alternative embodiment. For purposes of cleaning reusable drain container  50   a , however, it may be desirable to provide spout  80  a separate piece, as illustrated, which can be cleaned separately, and which allows spent fluid outlet  64  to have a larger diameter, so that debris within container  50   a  can be readily flushed out from within the container. 
         [0058]    Referring now to  FIGS. 11 and 12 , reservoir  100  illustrates one suitable reservoir for use with drain container  50   a . Reservoir  100  allows the patient or caregiver to remove a sample of the drained or spent fluid, e.g., spent dialysate, in a clean and efficient manner. In certain medical therapies, such as dialysis, it is necessary that the patient or caregiver take a sample of the spent fluid from the patient to a hospital or laboratory for analysis. The spent fluid tells the hospital many important things, such as the effectiveness of the patient&#39;s treatment, the effectiveness in removing different or certain impurities contained within the effluent, and whether the patient is at risk for any of a variety of infections, such as peritonitis common in dialysis. 
         [0059]    Reservoir  100  can be made of any of the materials discussed above for container  50   a . In an embodiment reservoir  100  has a nominal thickness of about 1 mm to about 7 mm, e.g., 4 mm Reservoir  100  in one embodiment is made of a clear material, such as those above for inlet cap  70 , so that the patient or caregiver can view the effluent fluid when reservoir  100  is removed from the drain container. It is known for dialysis that cloudy effluent can indicate the onset of peritonitis. Alternatively or additionally, it is contemplated to make part of drain container  50   a  clear or transparent, so that the patient can see the effluent within drain container  50   a . For example, drain container  50   a  could be glued or welded together from two or more pieces, wherein one or more of the pieces (e.g., front surface  52 ) is clear or transparent. For alternatively or additionally, one of the inlet and outlet caps can be clear or transparent. 
         [0060]    Reservoir  100  includes a fluid holding portion  102 , a fluid entry portion  104  and a container mating portion  106 . Fluid holding portion  102  is sized to hold a sufficient sample volume for the patient to take to a hospital or clinic. Fluid entry portion  104  tapers outwardly from fluid holding portion  102 . Fluid entry portion  104  defines a plurality of entry holes  108  that allow effluent fluid that enters drain container  50   a  to flow into and be held by fluid holding portion  102 . 
         [0061]    Portions  102 ,  104  and  106  are generally cylindrical as illustrated. Different cross-sectional shapes could be provided alternatively. Container mounting portion  106  is sized to fit sealingly on front surface  52  of container  50   a , for example. Placing reservoir  100  on front surface  52  allows reservoir  100  to extend downwardly into the container and become filled when the effluent fluid rises close to front surface  52  (which is the upper surface during treatment) of drain container  50   a . Accordingly, container mounting portion  106  is configured to extend a distance sufficient to set fluid holding portion  102  down into the container, so that the container does not have to be completely full for effluent fluid to begin to flow into apertures  108  of reservoir  100 . Apertures  108  are overflow slots that allow effluent to spill into reservoir  100  throughout therapy. 
         [0062]    Referring now to  FIG. 13 , tube stop  110  illustrates one suitable tube stop for container  50   a . Tube stop  110  can be made of any of the materials discussed above for container  50   a . Tube stop  110  can have a nominal thickness of about 1 mm to about 6 mm, e.g., 4 mm. Tube stop  110  includes a smaller diameter portion  112 , which flanges out to a larger diameter portion  114 . Smaller diameter portion  112  is capped at tube stop end  116 . As discussed above, drain tube  18  seals to the inside of smaller diameter portion  112  and abuts tube stop end  116  when inserted into cap  70  and tube stop  110 . Larger diameter portion  114  is solvent bonded or otherwise connected to outer projection  78   a  of cap  70 . Tube stop  110  is illustrated as being generally cylindrical, however, the tube stop can have different cross-sectional shapes as desired. 
         [0063]    Referring now to  FIGS. 14 and 15 , drain container  50   b  illustrates one alternative drain container of the present disclosure. Drain container  50   b  includes many of the same components as drain container  50   a , such as a front surface  152 , a rear surface (not seen in  FIG. 14 ) a top surface  156 , a bottom surface  158  and side surfaces  192 . Top surface  156  includes a handle  160 , which in both embodiments  50   a  and  50   b  is located closer to the front surface ( 52 / 152 ) of the respective container. Handles  60  and  160  are sized for one-handed operation in one embodiment. 
         [0064]    Bottom surface  158  of container  50   b  includes a snap-fitting groove (not seen), which snap-fits to an axel  202  of a wheel assembly  200  shown in  FIG. 14  and in further detail in  FIG. 17 . As further seen in  FIG. 14 , assembly  200  includes frame members  206  that connect to axle  202  of wheel assembly  200  and slide into grooves at the sides of container, such as grooves  94  at sides  92  of container  50   a . Although not seen in  FIG. 14 , sides  192  of container  50   b  include or define similar grooves or slots that are configured to accept members  206  of frame  200 . 
         [0065]    Drain container  50   b  also includes an effluent fluid outlet  164 , which is shown capped via a cap, which too can be clear for viewing effluent fluid. Drain container  50   b  also includes a drain fluid inlet, which in one embodiment is a drain fluid port  128  located on removable reservoir  120  of  FIG. 15 . 
         [0066]    One difference between drain container  50   b  and drain container  50   a  is the provision of a transparent or clear effluent viewing window  166  located on the front surface  152  of container  50   b . Effluent viewing window  166  allows the patient or caregiver to view the effluent fluid to see if it is cloudy or clear, cloudy indicating possible onset of peritonitis. It should be appreciated that viewing window  166  can be located in other suitable areas on container  50   b.    
         [0067]    Container  50   b  also includes an alternative sample reservoir  120 , which is connected removably and sealably to front surface  152  of container  50   b . Alternative reservoir  120  is shown in detail in  FIG. 15 . As seen in  FIG. 15 , alternative reservoir  120  includes a straight cylinder  122 , which defines a single inlet hole  124 . Here again, inlet hole  124  extends a suitable distance down into container  50   b  from front surface  152  when mounted into container  50   b , as described above for drain container  100 . A tube stop end  126  is sealed permanently or removably (e.g., via threads) to cylindrical housing  122 . Tube stop end  126  is sized to fit sealingly into an opening on front surface  152  of container  50   b . Cap  126  includes a drain tube port  128 , which is sized to allow drain tube  18  to fit sealingly through the port. 
         [0068]    Referring now to  FIG. 16 , drain container  50   c  illustrates another alternative drain container of the present disclosure. Container  50   c  includes many of the same features as containers  50   a  and  50   b , such as a front surface  252 , a rear surface (not seen in  FIG. 16 ), a top surface  256  defining a handle  260  at front surface  252 , a bottom surface  258  and sidewalls  292 . Drain container  50   c  also includes a drain fluid inlet  262  and a drain fluid outlet  264 . 
         [0069]    The primary difference between drain container  50   c  and the other containers is that drain container  50   c  includes a larger removable reservoir  210 , which in the illustrated embodiment has generally a T-shape. In the illustrated embodiment, reservoir  210  is mounted into a mating channel  212  defined in front surface  252  and in a small portion of side surfaces  292 . Reservoir  210  includes drain fluid inlet  262 , such that drained fluid from drain tube  18  initially enters reservoir  210  and flow from the reservoir via port  214  of drain container  50   c  through a sealingly mating hole or aperture  216  formed in channel  212  of front surface  252  of container  50   c . Reservoir  210  also includes a viewing window  218  (Alternatively all or some of the surface of reservoir  210  is formed of a clear or transparent material). Viewing window  218  allows the patient or caregiver to view effluent fluid immediately as it enters reservoir  210  during treatment and also allows the patient or caregiver to view the condition of the effluent that has mixed over the course of treatment, which eventually fills up within drain container  50   c  to the point that effluent fluid flows upward through port  214  into reservoir  210 . Reservoir  210  in the operable orientation shown collects a sample that is a mixture of each of the drains of the patient&#39;s therapy. In one embodiment, reservoir  210  is removed at the end of therapy for cleaning. 
         [0070]    It should appreciated that concepts described in connection with reservoir  210  and drain container  50   c  are not limited to the particular shape of reservoir  210  shown in  FIG. 16 . In a further alternative implementation, inlet  262  is provided elsewhere on front surface  252  or other surface of drain container  50   c.    
         [0071]    Referring now to  FIG. 17 , wheel assembly  200  discussed above in connection with container  50   b  of  FIG. 14  is illustrated in more detail. As described above, assembly  200  includes a pair of wheels  204  attached rotatably to an axle  202 , which is in turn coupled to sides members or shafts  206 . In  FIG. 17 , shafts  206  are larger diameter shafts that accept legs of a U-shaped telescoping handle  208 . The legs have a smaller diameter that fits moveably within shafts  206 . Handle  208  can have a button that is pressed to allow the legs of the handle to snap-fit into a retracted or extended position as desired. Handle  208  makes moving any of drain containers  50  (referring collectively to containers  50   a  to  50   c ) easier because the patient or caregiver can walk more upright during such movement. Telescoping handle  208  can replace or be provided in addition to the handles located integrally on drain containers  50 . The drain container handles help to load and unload the drain containers from wheel assembly  200  and to maneuver the drain container once removed. 
         [0072]    Referring now to  FIG. 18 , load cell assembly  230  illustrates one suitable load cell for use with any of the drain containers  50  discussed herein. Assembly  230  includes a platform  232  that surrounds a load cell  234 , which floats within a cutout  236  of platform  232 . Platform  232  further includes or defines wheel tracks  238 , which are sized in width to accept wheels  204  of wheel assembly  200 . Tracks  238  each include an indent or stop  240 , which is configured to grab and hold wheels  204  of assembly  200  for and during therapy and in turn hold drain container  50 , which is coupled to assembly  200 . 
         [0073]      FIG. 1  illustrates one embodiment in which load cell  12  is placed above wheeled base  28 . Load cell assembly  230  of  FIG. 18  illustrates an alternative embodiment in which assembly  230  itself rests on the ground. Assembly  230  accordingly includes wheels  242 , which connect to an axle  244 , which in turn is coupled rotatably to platform  232  of load cell assembly  230 . In this manner, the patient can roll assembly  230  with our without drain container  50  when the patient needs to move the entire medical fluid treatment system  10 . 
         [0074]    When the patient wishes to remove drain container  50  from load cell assembly  230 , the patient rotates wheel assembly  200  and likewise rotates drain container  50  off of assembly  230 , so that the female keying feature (e.g., feature  68  of container  50   a ) of drain container  50  is lifted off of a mating male keying feature  246  formed in the plate of load cell  232 . The patient or caregiver then pulls wheels  204  of assembly  200  out of indents  240  of track  238  and rolls drain container  50  and associated wheel assembly  200  down tracks  238 , off of a tapered front edge  248  of platform  232  and to the desired drain area of the patient&#39;s house, clinic or center as the case may be. 
         [0075]    In the illustrated embodiment, the load cell keying feature  246  is raised from load cell  234  to mate with a female or recessed mating keying feature (e.g., feature  68  of container  50   a ) of the drain container. Alternatively, the keying feature on load cell  234  is indented or female in nature, while the mating keying feature of the drain container is a projected or male type keying feature. 
         [0076]    Platform  232  of load cell assembly  230  is made of relatively rugged and durable material, such as a polycarbonate, acrylonitrile butadiene styrene (“ABS”) or a combination thereof. Load cell  234  in one embodiment includes a metal plate, attached to strain gauge apparatus, which is known in the art. Load cell  234  mates with projected surface  69  (see  FIGS. 2 ,  4  and  5 ) of container  50   a  (or other like surface of other containers herein). Projected surface  69  allows load cell  234  to measure the full weight of container  50   a . Electronics of instrument  20  are programmed to know the dry weight of container  50  to determine the absolute weight of effluent and/or to subtract the weight of container  50  at the beginning of treatment from the weight of container and effluent at the end of treatment to determine the total weight of effluent collected. 
         [0077]    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.