Patent Description:
Connectors for quick coupling are known from <CIT> and <CIT>.

Hemodialysis is a medical procedure that is used to achieve the extracorporeal removal of waste products including creatine, urea, and free water from a patient's blood involving the diffusion of solutes across a semipermeable membrane. Failure to properly remove these waste products can result in renal failure.

During hemodialysis, the patient's blood is removed by an arterial line, treated by a dialysis machine, and returned to the body by a venous line. The dialysis machine includes a dialyzer containing a large number of hollow fibers forming a semipermeable membrane through which the blood is transported. In addition, the dialysis machine utilizes a dialysate liquid, containing the proper amounts of electrolytes and other essential constituents (such as glucose), that is also pumped through the dialyzer.

Typically, dialysate is prepared by mixing water with appropriate proportions of an acid concentrate and a bicarbonate concentrate. Preferably, the acid and the bicarbonate concentrate are separated until the final mixing right before use in the dialyzer as the calcium and magnesium in the acid concentrate will precipitate out when in contact with the high bicarbonate level in the bicarbonate concentrate. The dialysate may also include appropriate levels of sodium, potassium, chloride, and glucose.

The dialysis process across the membrane is achieved by a combination of diffusion and convection. The diffusion entails the migration of molecules by random motion from regions of high concentration to regions of low concentration. Meanwhile, convection entails the movement of solute typically in response to a difference in hydrostatic pressure. The fibers forming the semipermeable membrane separate the blood plasma from the dialysate and provide a large surface area for diffusion to take place which allows waste, including urea, potassium and phosphate, to permeate into the dialysate while preventing the transfer of larger molecules such as blood cells, polypeptides, and certain proteins into the dialysate. Typically, the dialysate flows in the opposite direction to blood flow in the extracorporeal circuit. The countercurrent flow maintains the concentration gradient across the semipermeable membrane so as to increase the efficiency of the dialysis.

Connectors are integral parts of most medical device machines. The connectors used in many medical devices, such as hemodialysis machines, are often reusable. Reusable components used in medical devices present numerous problems, including a risk of cross-contamination, infections, and healthcare-associated infections (HAIs). Reusable components and devices are designed and built to last indefinitely, assuming they are properly maintained and cleaned. Even if decontaminated properly, however, reusable devices can still lead to infection. There are also many possible harmful effects from the disinfectant chemicals being used. For example, formaldehyde, which is a commonly used disinfectant, is a known carcinogen. It can also cause severe allergic reactions, liver damage, anemia, CNS disorders, destruction of red blood cells, reproductive disorders, and kidney transplant rejection.

These risks are lower in single-use components and devices, which are sterilized and individually packaged. This reduces the spread of infection. Moreover, single use components and devices are usually associated with lower costs and increased efficiency. Single-use components and devices are designed to have less-demanding durability requirements. This allows for more cost-effective, mass production techniques.

Accordingly, there is a significant need for single-use connectors, e.g., connectors that permanently lock and cannot be released through external access, e.g., with a tool or a user's finger, for use with hemodialysis systems.

A hemodialysis system will be here described including an arterial blood line for connecting to a patient's artery for collecting blood from a patient, a venous blood line for connecting to a patient's vein for returning blood to a patient, a reusable dialysis machine and a disposable dialyzer with a disposable connector(s) for joining the conduits between the dialyzer and the dialysate solutions.

The arterial blood line and venous blood line may be typical constructions known to those skilled in the art. For example, the arterial blood line may be traditional flexible hollow tubing connected to a needle for collecting blood from a patient's artery. Similarly, the venous blood line may be a traditional flexible tube and needle for returning blood to a patient's vein. Various constructions and surgical procedures may be employed to gain access to a patient's blood including an intravenous catheter, an arteriovenous fistula, or a synthetic graft.

Preferably, the disposable dialyzer has a construction and design known to those skilled in the art including a blood flow path and a dialysate flow path. The term "flow path" is intended to refer to one or more fluid conduits, also referred to as passageways, for transporting fluids. The conduits may be constructed in any manner as can be determined by ones skilled in the art, such as including flexible medical tubing or non-flexible hollow metal or plastic housings. The blood flow path transports blood in a closed loop system by connecting to the arterial blood line and venous blood line for transporting blood from a patient to the dialyzer and back to the patient. Meanwhile, the dialysate flow path transports dialysate in a closed loop system from a supply of dialysate through a connector to the dialyzer and back through a connector to the dialysate supply. Both the blood flow path and the dialysate flow path pass through the dialyzer, but are separated by the dialyzer's semipermeable membrane.

The invention provides a connector to receive and join first and second conduits, the connector comprising: a sleeve comprising an elongate tubular body having an interior chamber, a first opening at a first end, a second opening at a second end, and at least one flexible finger having a barb at a free end, wherein the first opening comprises a substantially circular shape with at least one slot positioned along the periphery of the circular shape, and wherein the at least one flexible finger is attached to the first end at the first slot and extends into the interior chamber; a collet configured to be housed within the interior chamber of the sleeve, the collet comprising first and second cylindrical bodies each having a first end and a second end, the first end of the second cylindrical body joining the second end of the first cylindrical body to form a shoulder, at least one ridge extending along a longitudinal axis on an outer surface of the first cylindrical body, a collar disposed along the outer surface of the first cylindrical body between the at least one ridge and the shoulder, a first gap formed between the at least one ridge and the collar and a second gap formed between the collar and the shoulder, and first and second deflectable flanges located in a region near the second end of the second cylindrical body and having a first and a second surface or circumferential ridge on an interior side of the first and second flanges, respectively, wherein the first end of the first cylindrical body is configured to pass through the first opening of the sleeve, such that the at least one ridge passes through the at least one slot, wherein an end of the first conduit is configured to pass through the opening of the first cylindrical body into a lumen of the first cylindrical body and wherein an end of the second conduit is configured to pass through the second end of the second cylindrical body into a lumen of the second cylindrical body, wherein in a first position, the barb is housed within the first gap, and wherein in a second position, the barb is housed within the second gap and the first and second surface or circumferential ridges are housed with a first and second recess in an outer surface of the second conduit.

In another embodiment, the first conduit transfers dialysate solution and the second conduit is an elongate tubular projection extending from a body of a dialyzer.

In another embodiment, the first opening of the sleeve further comprises an additional slot, wherein the at least one slot and the additional slot are positioned along the periphery of the circular shape approximately <NUM>° apart. The collet may further comprise an additional ridge extending along the longitudinal axis on the outer surface of the first cylindrical body, wherein the at least one ridge and the additional ridge are positioned approximately <NUM>° apart around the first cylindrical body, and wherein the additional ridge and the annular collar forms a third gap. The additional ridge may be configured to pass through the additional slot.

In another embodiment, the sleeve further comprises an additional flexible finger having a barb at a free end and attached to the first end at the additional slot and extends into the interior chamber. In the first position, the barb of the additional flexible finger is housed within the third gap. In the second position, the barb of the additional flexible finger is housed within the second gap.

In another embodiment, the collet further comprises an O-ring disposed within an interior chamber of the second cylindrical body near the shoulder. In the second position, the end of the second conduit resides within a lumen of the O-ring.

In another embodiment, the sleeve further comprises first and second recesses on a surface of the interior chamber, and wherein at least a portion of the first and second deflectable flanges are housed within the first and second recesses when in the second position.

In another embodiment, the sleeve further comprises first and second projections located between the first and second recesses and the first end of the sleeve, wherein the second cylindrical body further comprises first and second recesses located on an outer surface between the first and second deflectable flanges and the shoulder. The first and second projections may be housed within the first and second recesses located on an outer surface of the second cylindrical body when in the second position.

In another embodiment, when in the second position, the barb cannot be removed from the second gap by external access, e.g., with a tool or with the user's finger. The barb is permanently housed within the second gap and the first and second surface or circumferential ridges are permanently housed with the first and second recess in the outer surface of the second conduit in the second position.

While the present invention is capable of embodiments in various forms, as shown in the drawings, hereinafter will be described the presently preferred embodiments of the invention with the understanding that the present disclosure is to be considered as an exemplification of the invention, and it is not intended to limit the invention to the specific embodiments illustrated.

A portion of a hemodialysis system is depicted in <FIG>, <FIG>, <FIG>, and <FIG>. The hemodialysis system includes dialyzer <NUM> that is connected to both a blood flow path and a dialysate flow path. Both the blood flow path and dialysate flow path travel through dialyzer <NUM> to transport their respective fluids through closed loop systems wherein the dialysate flow path is isolated from the blood flow path by a semipermeable membrane (not shown). Preferably, the dialysate flows in the opposite direction to blood flow within dialyzer <NUM>, which possesses an inlet <NUM> for receiving dialysate, an outlet (not shown) for expelling dialysate, an inlet (not shown) for receiving blood from a patient, and an outlet <NUM> for returning blood to a patient. The blood flow path and dialysate flow path are conduits. The conduits may have an inside diameter of approximately <NUM> inch (<NUM>-<NUM> millimeters). Both the blood flow path and the dialysate flow path pass through dialyzer <NUM>, but are separated by the dialyzer's semipermeable membrane. Dialyzer <NUM> is of a construction and design known to those skilled in the art. Preferably, dialyzer <NUM> includes a large number of hollow fibers which form a semipermeable membrane. Suitable dialyzers can be obtained from Fresenius Medical Care, Baxter International, Inc. , and Nipro Medical Corporation.

As seen in <FIG>, locking connector <NUM> that joins a first conduit or solution transferring line <NUM>, such as a dialysis solution circulating hose, to second conduit, such as an inlet <NUM> or outlet (not shown) of dialyzer <NUM> is described. As seen in <FIG>, connector <NUM> comprises female element or sleeve <NUM>. Sleeve <NUM> is an elongate tubular body having an opening <NUM> at first end <NUM>, and lumen or interior chamber <NUM> communicating with opening <NUM> at first end <NUM> and opening <NUM> at second end <NUM>. An outer surface of sleeve <NUM> may have annular recess <NUM> to assist a user with gripping connector <NUM>. Recesses <NUM> situated on the outer surface of sleeve <NUM> may also assist the user with gripping connector <NUM>. Opening <NUM> at first end <NUM> is configured to receive an end portion of a fluid-flow conduit <NUM> and has a substantially circular shape with two slots <NUM> along the periphery of the circle arranged approximately <NUM>° apart in the circle. Sleeve <NUM> also includes two flexible fingers <NUM> that extend into lumen <NUM> of sleeve <NUM> from the edge of slots <NUM> located along the perimeter of the circular opening <NUM> at first end <NUM>, the two flexible fingers <NUM> including enlarged free ends or barbs <NUM>. The interior chamber of sleeve <NUM> defining lumen <NUM> is substantially cylindrical, tapering slightly towards first end <NUM>, such that the diameter of lumen <NUM> at second end <NUM> is larger than the diameter of lumen <NUM> at first end <NUM>. Sleeve <NUM> has a substantially circular opening <NUM> at second end <NUM> through which a male component or collet <NUM> is received. As seen in <FIG>, the interior surface of sleeve <NUM> include two indentations or recesses <NUM> in the region at second end <NUM> of sleeve <NUM> that are arranged approximately <NUM>° apart in the circle defined by the sleeve. The two indentations or recesses <NUM> are also arranged such that they are each offset by approximately <NUM>° from flexible fingers <NUM> at first end <NUM>. Sleeve <NUM> also includes first and second projections <NUM> located directly above each indentation, such that the projections are also arranged so that they are each offset by approximately <NUM>° from flexible fingers <NUM> at first end <NUM>.

As seen in <FIG>, connector <NUM> also includes a male component or collet <NUM> that is configured to be received in interior chamber <NUM> of sleeve <NUM>. Collet <NUM> has first and second ends <NUM>, <NUM> and includes first and second cylindrical bodies <NUM>, <NUM>, each having a lumen <NUM>, <NUM>, respectively. Lumen <NUM> of first cylindrical body <NUM> communicates with lumen <NUM> of second cylindrical body <NUM>. First cylindrical body <NUM> has a smaller diameter (both inner and outer) than second cylindrical body <NUM> and terminates at first end <NUM> of collet <NUM>. Collet <NUM> has a shoulder or shelf <NUM> where second cylindrical body <NUM> meets, joins, or connects to first cylindrical body <NUM>. Collet <NUM> has an outer surface of first cylindrical body <NUM> that includes posts or ridges <NUM> extending along a longitudinal axis of the first cylindrical body and collar <NUM> that forms first and second annular ridges <NUM>, <NUM>, first annular ridge <NUM> being closer to first end <NUM> of collet <NUM> than second annular ridge <NUM>. First annular ridge <NUM> may be smaller than second annular ridge <NUM>. Posts or ridges <NUM> extend from first end <NUM> of collet <NUM> down along a longitudinal axis of first cylindrical body <NUM>, approximately about half (<NUM>/<NUM>) of the length of the first cylindrical body, alternatively about one-third (<NUM>/<NUM>), alternatively about two-thirds (<NUM>/<NUM>), alternatively about three-fourths (<NUM>/<NUM>) of the length of first cylindrical body <NUM>, and terminate before first annular ridge <NUM> of collar <NUM>. The ends of each of the posts or ridges <NUM> and the first annular ridge <NUM> form first and second gaps <NUM> that are configured to hold enlarged ends or barbs <NUM> of the flexible fingers <NUM>. The second annular ridge <NUM> of collar <NUM> and shoulder or shelf <NUM> forms an annular gap <NUM> that is also configured to hold enlarged ends or barbs <NUM> of the flexible fingers <NUM>.

As seen in <FIG>, the interior of first cylindrical body <NUM> includes annular ridge <NUM> that lies on the interior surface of the first cylindrical body, positioned between the first and second annular ridges <NUM>, <NUM> located on the outside of first cylindrical body <NUM>. Second cylindrical body <NUM> has first and second flexible, deflecting or deflectable flanges <NUM> in the region near second end <NUM> of collet <NUM>. Flanges <NUM> include ribs <NUM> running along a horizontal axis of flange <NUM> that are configured to lock into an opening, recess, or gap <NUM> in the outer surface of the inlet (e.g., from the dialyzer) to be connected. As seen in <FIG>, the outer surface of second cylindrical body <NUM> also includes first and second recesses <NUM> above flanges <NUM>, located between flanges <NUM> and the shoulder or shelf <NUM>, that are configured to house projections <NUM> in the interior of sleeve <NUM>. The outer diameter of first cylindrical body <NUM> is slightly smaller than the diameter of opening <NUM> of sleeve <NUM> at first end <NUM>, such that first cylindrical body <NUM> is configured to pass through opening <NUM> of sleeve <NUM> at first end <NUM>, and posts or ridges <NUM> on the outside surface of first cylindrical body <NUM> pass through slots <NUM> in opening <NUM> at first end <NUM> of sleeve <NUM>. An O-ring <NUM> is seated in annular groove <NUM> in the lumen <NUM> of second cylindrical body <NUM> adjacent to shelf or shoulder <NUM> (see <FIG>).

<FIG> show sleeve <NUM> with fluid-flow conduit <NUM>, e,g. , dialysis tubing, inserted into opening <NUM> at first end <NUM> of sleeve <NUM> and through opening <NUM> in first end <NUM> of collet <NUM> such that tubing <NUM> resides in lumen <NUM> of first cylindrical body <NUM> and abuts the annular ridge <NUM> in the interior of first cylindrical body <NUM>. Collet <NUM> is inserted through opening <NUM> in second end <NUM> of sleeve <NUM> and resides in interior chamber <NUM>. As seen in <FIG>, with respect to sleeve <NUM>, collet <NUM> is oriented such that deflectable flanges <NUM> are residing within indentations or recesses <NUM> in the interior surface of sleeve <NUM> and projections <NUM> above indentations <NUM> are housed within first and second recesses <NUM> in the outer surface of the second cylindrical body near the shoulder or shelf. As seen in <FIG>, which shows the connector rotated <NUM>° from the view in <FIG>, barbs or enlarged ends <NUM> of the flexible fingers <NUM> reside in first and second gaps <NUM> formed between the ends of each of the or ridges <NUM> and first annular ridge <NUM>, thereby temporarily locking collet <NUM> in a first position in the interior chamber of sleeve <NUM>.

As seen in <FIG>, inlet <NUM> (or outlet, not shown) is inserted through opening <NUM> at second end <NUM> of collet <NUM> such that a distal region of inlet <NUM> (or outlet) is housed within the lumen <NUM> or interior chamber of second cylindrical body <NUM>. Inlet <NUM> (or outlet) is inserted into lumen <NUM> of second cylindrical body <NUM> and advanced until the end abuts shoulder or shelf <NUM> and resides within the lumen of O-ring <NUM>. Surface or circumferential ridges <NUM> of deflectable flanges <NUM> are adjacent the gaps or recesses <NUM> in the outer surface of the inlet <NUM> (or outlet), but the deflectable flanges <NUM> are still extending radially outward such that surface or circumferential ridges <NUM> are not locked into the gaps or recesses <NUM> of inlet <NUM> (or outlet). As seen in <FIG>, which is a <NUM>° rotation of the view in <FIG>, collet <NUM> is still in the first position in the interior chamber <NUM> of sleeve <NUM>, i.e., barbs or enlarged ends <NUM> of flexible fingers <NUM> still reside in first and second gaps <NUM> formed between the ends of each of the or ridges <NUM> and the first annular ridge <NUM> of collar <NUM>, and projections <NUM> above indentations <NUM> are housed within first and second recesses <NUM> in the outer surface of the second cylindrical body near the shoulder or shelf.

As seen in <FIG>, collet <NUM>, with inlet <NUM> disposed within interior chamber <NUM> of second cylindrical body <NUM>, has been advanced further in the direction of first end <NUM> of sleeve <NUM>, such that first end <NUM> of first cylindrical body <NUM> is moved farther past first end <NUM> of sleeve <NUM>. The advancement of collet <NUM> forces barbs <NUM> out of gaps <NUM> and projections <NUM> out of first and second recesses <NUM> in the outside surface of second cylindrical body <NUM>. Moreover, pressure from the interior surface of sleeve <NUM> forces surface or circumferential ridges <NUM> on the deflectable flanges <NUM> to be housed within gaps or recesses <NUM> in the outer surface of inlet <NUM> (or outlet).

As seen in <FIG>, further advancement of collet <NUM> in the direction of first end <NUM> of sleeve <NUM> forces barbs <NUM> of flexible fingers <NUM> into the annular gap <NUM> between second annular ridge <NUM> and shoulder or shelf <NUM>. This results in collet <NUM> being permanently locked to sleeve <NUM>, thereby permanently connecting the dialyzer inlet <NUM>(or outlet) to the fluid-flow conduit <NUM> (e.g., dialysate tubing). Sleeve <NUM> does not contain any external access point such that the user could release barbs <NUM> of flexible fingers <NUM> from annular gap <NUM> with, e.g., a finger or a tool.

Claim 1:
A connector (<NUM>) to receive and join first and second conduits (<NUM>,<NUM>), the connector comprising:
a sleeve (<NUM>) comprising an elongate tubular body having an interior chamber (<NUM>), a first opening (<NUM>) at a first end (<NUM>) , a second opening (<NUM>) at a second end (<NUM>) , and at least one flexible finger (<NUM>) having a barb (<NUM>) at a free end, wherein the first opening comprises a substantially circular shape with at least one slot (<NUM>) positioned along the periphery of the circular shape, and wherein the at least one flexible finger is attached to the first end at the first slot and extends into the interior chamber;
a collet (<NUM>) configured to be housed within the interior chamber of the sleeve, the collet comprising first and second cylindrical bodies (<NUM>,<NUM>) each having a first end and a second end, the first end of the second cylindrical body joining the second end of the first cylindrical body to form a shoulder (<NUM>), at least one ridge (<NUM>) extending along a longitudinal axis on an outer surface of the first cylindrical body, a collar (<NUM>) disposed along the outer surface of the first cylindrical body between the at least one ridge and the shoulder, a first gap (<NUM>) formed between the at least one ridge and the collar and a second gap (<NUM>) formed between the collar and the shoulder, and first and second deflectable flanges located in a region near the second end of the second cylindrical body and having a first and a second circumferential ridge (<NUM>) on an interior side of the first and second flanges, respectively, ,
wherein an end of the first conduit is configured to pass through the opening of the first cylindrical body into a lumen (<NUM>) of the first cylindrical body and wherein an end of the second conduit is configured to pass through the second end of the second cylindrical body into a lumen (<NUM>) of the second cylindrical body,
wherein in a first position, the barb is housed within the first gap, and
wherein in a second position, the barb is housed within the second gap and the first and second circumferential ridges are housed with a first and second recess in an outer surface of the second conduit;
characterised in that the first end of the first cylindrical body is configured to pass through the first opening of the sleeve, such that the at least one ridge passes through the at least one slot.