Patent Description:
In medical practice there are several circumstances where fluid samples are required to be taken from blood vessels or body cavities, but where accidental injection of substances, such as pharmaceuticals, glucose or air is undesirable, detrimental or could be fatal. One instance is where blood samples are required to be withdrawn from the arterial system. This is typically done using a three-way tap which allows for sampling through one port and for flushing with saline through another port. Another instance is where a fluid sample has to be taken from the subarachnoid space of the brain. There are also a number of medical procedures requiring one-way flow of body fluid where it would be beneficial to prevent the flow of body fluid in the opposite, "wrong" direction. For example, cardiopulmonary bypass equipment requires blood to flow from the arterial system out of the body and back into the body via the venous system and it would be beneficial to prevent the possibility of reverse direction flow which might result from user error.

<CIT> discloses a sampling connector for use as an adapter for a three-way tap arterial blood sampling device, which connector incorporates a one-way valve allowing fluid to flow through the connector in one direction only. This connector is attached onto the sampling port of the three-way tap so that fluid can only flow in a direction from the body and out of the sampling port. The connector is also disclosed as including a stop valve which prevents fluid flowing out of the outer end of the connector body (namely the end remote from the sampling port of the three-way tap) unless a complementary end of a separate device engages the outer end and opens the stop valve. This prevents leakage of body fluid through the tap and the connector when a separate device, such as a sample collecting syringe, is not attached to the connector.

It should be noted that connector devices which incorporate only a stop valve having aforesaid function, namely preventing fluid from flowing out of one end of the connector body unless a complementary end of a separate device engages that end and opens the stop valve, are commercially available and are routinely used in respect of standardised medical equipment, particularly for connection to patient fluid lines. These known connector devices typically have a male end formed as a Luer slip connector or Luer lock connector and a female end comprising a female Luer connector, and the stop valve is mounted adjacent the female end to provide a needleless entry port, into which a complementary male Luer connector is inserted in order to open that port. Such connector devices are, for example, provided on bags of saline or other fluid for medical purposes for standardised connection to patient fluid supply lines provided with male Luer lock connection means.

While <CIT> discloses desirable inclusion of a one-way valve and a stop valve in an adapter for arterial blood sampling by way of a three-way tap, the present invention is concerned with manufacture of a connector, for this purpose and other purposes, with the objective of ease of assembly and quality assurance, hence highly cost-effective supply of reliable medical connectors as required by modern medical services.

<CIT>, <CIT> and <CIT> disclose further examples of known sampling connectors, and <CIT> discloses a medical connector including a vacuum device and a valve for withdrawing a gas from the particulate biomaterial and introducing the liquid biomaterial.

The invention is defined by the subject-matter of independent claims <NUM>, <NUM> and <NUM>.

According to an aspect of the invention, there is provided a medical connector comprising a connector body having first and second apertures in fluid communication via a fluid flow conduit, a one-way valve disposed in the body to allow fluid to flow from the first aperture, through the fluid flow conduit and out of the second aperture, but not to allow fluid to flow from the second aperture and through the fluid flow conduit to the first aperture, and a stop valve which prevents fluid flowing out of the second aperture of the connector body unless a complementary end of a separate device engages the second aperture and opens the stop valve, wherein the connector body, the one-way valve is fitted directly into an end of the stop valve part in a manner providing a fluid tight seal between these valve parts. The one-way valve and the stop valve are formed as parts of a single piece of elastomeric material, said parts may be hingedly connected such that the one-way valve part is folded over and fitted directly into the end of the stop valve part.

Optionally, the end of the stop valve into which the one-way valve is fitted is formed with a recess and a periphery of the one-way valve seats in that recess. The recess may be configured so that the one-way valve is fully counter sunk into the end of the stop valve.

In certain embodiments, the one-way valve part and the stop valve part may be additionally connected by a strap portion of the elastomeric material, said strap may be folded over such that the one-way valve fits into the end of the stop valve.

The one-way valve may be a duck bill valve. The stop valve may be a swabable entry port valve. The connector body may be formed of only two body parts. The connector body may be formed in one piece with a folding, snap fit closure.

In certain embodiments, the first aperture may be within a male end of the connector which is configured as a male Luer lock connector portion. Additionally or alternatively, the second aperture may be within a female end of the connector which is configured as a female Luer lock connector portion and provides a swabable entry port for attachment of a complementary needleless device.

According to a further aspect of the invention, there is provided a three-way tap arterial blood sampling device incorporating the sampling connector according to the either of the medical devices described above.

According to a further aspect of the invention, there is provided a method of producing a medical connector, e.g. as described above, comprising the steps of: forming a one-way valve and a stop valve; forming parts of a connector body; mounting the stop valve and the one-way valve inside the body parts so that the one-way valve fits directly into one end of the stop valve, including folding the one-way valve part over relative to the stop valve part; and attaching the body parts together.

According to a further aspect of the invention, there is provide a method of producing a medical connector, e.g. as described above, comprising the steps of: forming a one-way valve and a stop valve; forming a connector body in one piece with a folding, snap fit closure; mounting the stop valve and the one-way valve inside the connector body so that the one-way valve fits directly into one end of the stop valve, including folding the one-way valve part over relative to the stop valve part; and closing the connector body by folding and snap fitting the closure.

In certain embodiments, the connector body may be formed from only two parts and/or the assembled valve parts may be fitted into one part of the body and/or the other part of the body may then be attached thereto.

In certain embodiments, forming the end of the stop valve, into which the one-way valve is to be fitted, may be with a recess and fitting the one-way valve to that end of the stop valve so that a periphery of the one-way valve seats in that recess.

The method described above may further include configuring the recess so that the one-way valve is fully counter sunk into the end of the stop valve with an end surface of the one-way valve flush with an end surface of the stop valve. Additionally or alternatively, the step of forming the one-way valve and the stop valve as parts of a single piece of elastomeric material may include cutting respective slits in each part, namely each valve.

In certain embodiments, after attaching the body parts together, automated function testing by applying compressed air followed by suction pressure from either end of the connector may be carried out. Additionally or alternatively, as may checking for predetermined flow rate upon the application of compressed air and checking for maintained pressure upon application of suction pressure.

The invention will be described further with reference to the accompanying drawings, in which:.

A medical sampling connector which has been trialled publicly by the applicant is shown in <FIG>. This comprises a body <NUM>, formed by an outer body sleeve <NUM> and an inner body sleeve <NUM>, and inside the body <NUM> there is mounted a one-way valve <NUM> and a stop valve <NUM>. As best shown in <FIG>, the one-way valve is mounted between the outer body sleeve <NUM> and the inner body sleeve <NUM>, while the stop valve <NUM> is separately mounted inside the distal end of the inner body sleeve <NUM>.

The outer body sleeve <NUM> is provided at a first end with a male Luer lock connector portion <NUM> which, in use, is designed to fit to a sampling port of a known three-way tap for arterial blood sampling. The inner body sleeve <NUM> fits into the opposing, second end of the outer body sleeve <NUM> and projects a distance beyond the second end, as shown in <FIG>. The inner body sleeve <NUM> is itself formed of two parts, namely a swabable closure portion <NUM> and a tubular extension <NUM>, and it is the closure portion <NUM> which projects from the second end of the sleeve <NUM>. Thus, the connector body <NUM> as a whole has a first end <NUM> and a second end <NUM> and provides a fluid flow passage from a first aperture at the first end <NUM> to a second aperture at the second end <NUM>. The first end <NUM> is provided by the outer body sleeve <NUM> and the second end <NUM> is provided by the projecting closure portion <NUM> of the inner body sleeve <NUM>.

Components <NUM>, <NUM>, <NUM> of the body <NUM> are moulded of known medical grade thermoplastic material and are substantially rigid.

The stop valve <NUM> which is mounted inside the inner body sleeve <NUM>, primarily within the closure portion <NUM>, is a known configuration of swabable entry valve <NUM> of elastomeric material, such as medical grade silicon rubber. The end of this valve <NUM> has an end wall which is flush with the free end <NUM> of the closure portion <NUM> and which is formed with a slit <NUM>, as shown in <FIG>. The swabable entry valve <NUM> is accommodated in the inner body sleeve <NUM>, as shown. It extends only a short distance into the tubular extension <NUM>, which is connected on to the closure portion <NUM>, typically by welding or by adhesive and provides a rear valve seat for the valve <NUM>. The swabable entry valve <NUM> acts as a stop valve in that it prevents fluid, specifically liquid, which enters the connector body <NUM> from the first end <NUM> leaking out of the second end <NUM>, but allows liquid to flow from the first end <NUM> to the second end <NUM> and out through the second end when a further complementary connector portion engages with the closure portion <NUM> and opens the slit <NUM> by projecting there through. In this respect, the closure portion <NUM> carries external screw threads and the complementary connector portion will typically be a standardised male Luer lock connector portion, similar to that at the first end <NUM> of the connector body <NUM>.

A component consisting of the inner body sleeve <NUM> with the swabable entry valve <NUM> mounted therein is a previously known commercially available component, widely used as a connector fitment on a bag of saline or other medical fluid for enabling quick connection of same to a Luer lock connector portion at one end of a patient fluid supply line.

The one-way valve <NUM> is in the form of a duck bill valve, namely a body of elastomeric material having a circular disc base <NUM> and a tapered extension <NUM> from one side of the base which has a slit <NUM> through its pointed end. Fluid is therefore able to flow through this valve <NUM> from the direction of the base <NUM> and through the slit <NUM>, but is not able to flow in the reverse direction because fluid at the outside of the tapered extension <NUM> exerts pressure on the outside of the extension to close the slit <NUM>.

As shown in <FIG>, the one-way valve <NUM> is mounted in the interior of the outer body sleeve <NUM>, centrally in the flow path through the connector, just inside the male Luer lock connector portion <NUM>, with the base <NUM> seated in an annular recess in the outer body sleeve <NUM> and the tapered portion <NUM> extending downstream in the direction of flow from the first to the second end of the body <NUM>. The one-way valve <NUM> is retained in this position by the extension <NUM>, which effectively acts as a spacer between the one-way valve <NUM> and the stop valve, namely the swabable entry valve <NUM>.

Conforming to accepted colour coding within the UK health service, the outer body sleeve <NUM> is coloured red to show that the connector is a one-way connector appropriate for connection to arterial sampling lines so that blood can only flow one-way, out of the patient and no liquid can flow in.

The functioning of the one-way, arterial connector shown in <FIG> has been found to be satisfactory, but assembly of this device is difficult, time-consuming and may not be totally reliable in sealing around the one-way valve <NUM>.

The present invention addresses the need for more cost-effective and reliable assembly of such a medical use connector incorporating both a one-way valve and a stop valve.

<FIG> illustrate a preferred practical embodiment of a connector in accordance with the present invention. This comprises a one-way valve <NUM> and a stop valve <NUM> which are formed, by moulding, as parts of a single piece of elastomeric material, as shown in <FIG>. These parts are hingedly connected by way of a short strap <NUM> of the elastomeric material. A suitable elastomeric material is medical grade silicon rubber.

The stop valve part <NUM> has a through bore <NUM> between a first end <NUM> and a second end <NUM>. The bore <NUM> is closed at the first end <NUM> by an end wall provided with a slit <NUM>. An annular recess <NUM> is formed at the second end <NUM> as an enlargement of the through bore <NUM>. The strap <NUM> connecting to the one-way valve <NUM> is connected at this second end <NUM>. As illustrated in the sequence from <FIG>, an integrated one-way and stop valve is assembled by the one-way valve part <NUM> folding round and fitting into the recess <NUM>. In this respect, the one-way valve part <NUM> is formed as a duck bill valve with a circular disc base <NUM> and a tapered extension <NUM> which has an elongate slit <NUM> at its pointed end, as indicated in <FIG>. Accordingly, when the stop valve <NUM> is folded into position, the disc <NUM> fits snugly into the recess <NUM> to provide a fluid tight seal between these valve parts <NUM>, <NUM>, with the tapered portion <NUM> projecting into the bore <NUM>. As shown, the base <NUM> of the one-way valve <NUM> is preferably fully counter sunk into the recess <NUM> in the end <NUM> of the stop valve part <NUM>.

A shallow recess <NUM> is provided radially in the end surface of the stop valve at its second end <NUM> to accommodate the strap <NUM>.

This integrated stop valve and one-way valve, shown in its final disposition in <FIG>, also <FIG>, is therefore simple and cost-effective to manufacture in a single moulding. One or both of the slits <NUM>, <NUM> may be formed by cutting the material from which the respective valve parts <NUM>, <NUM> are made. It is also easy to assemble without any skill and, in a particularly reliable manner, the stop valve <NUM> will always be fitted in correct orientation directly into the end <NUM> of the one-way valve <NUM>. Importantly also, a reliable fluid tight seal will be formed between these two valve parts <NUM>, <NUM> between contacting surfaces of the disc <NUM> and the annular recess <NUM>. Thus, this particular arrangement has the advantages both of economic production and of self-alignment of the two valve parts during assembly. The alignment results in reliability of sealing between the respective valve parts.

As shown in <FIG>, this particular practical embodiment of connector in accordance with the present invention has an outer body <NUM> formed of two parts <NUM>, <NUM> only. The first part <NUM> provides a male Luer lock connector <NUM>, with conventional male Luer tapered central projection surrounded by an internally threaded collar. The second part <NUM> serves as a housing for the integrated one-way and stop valve <NUM>/<NUM> and provides an externally threaded female end <NUM> to the connector body <NUM>. The second part <NUM> has an annular projection <NUM> at its end opposite to the externally threaded portion <NUM>, while the first part <NUM> has a corresponding annular groove <NUM> in its end facing away from the male Luer lock arrangement <NUM>. The parts <NUM>, <NUM> are accordingly connected together to form the outer body <NUM> by location of the projection <NUM> into the mating groove <NUM> and by use of adhesive or by means of ultrasonic welding, for example. These parts <NUM>, <NUM> are suitably made from medical grade ABS or similar hard thermoplastics material. To comply with required convention for colour coding, the part <NUM> will be coloured red to signify that the connector incorporates a one-way valve, while the part <NUM> will be of substantially transparent material.

The assembly process of the connector is illustrated in <FIG>, by cross-sectional views, and correspondingly by <FIG>, isometric views. First of all the integrated one-way and stop valve <NUM>, <NUM> is produced by folding over the one-way valve <NUM> to fit directly into the end <NUM> of the one-way valve <NUM>, as previously described. This integrated valve is then located into the body part <NUM>, as shown in <FIG> so that the end wall <NUM> of the valve part <NUM> is substantially flush with the threaded end <NUM> of the body part <NUM>, and a substantial portion of the remainder of the cylindrical outer surface of the valve part <NUM> is in contact with the inner surface of the body part <NUM>. The other body part <NUM> is then located onto the end of the body part <NUM> with the projection <NUM> locating in the groove <NUM> and being affixed in fluid tight manner by ultrasonic or radio-frequency welding process or by adhesive, as previously described, so that the inner, mating face of the body part <NUM> also seals against the end surface of the conjoined stop valve <NUM> and one-way valve <NUM>.

After connecting the outer body parts <NUM>, <NUM> together, automated testing of the fluid tight seal can be undertaken by applying compressed air followed by suction pressure from either end of the assembled connector, checking for predetermined flow rate upon the application of compressed air and checking for maintained pressure upon application of suction pressure.

The outer body part <NUM> and the stop valve part <NUM> mounted therein provide a swabable needleless access port comparable to that of the <FIG> embodiment of the prior art and other prior art medical connectors. This is necessary for the connector of the invention to be compatible with connector portions of existing medical devices, in this case conventional male Luer lock connector portions of sampling syringes since this embodiment of the connector of the invention will typically be used at the sampling port of a three-way tap for arterial blood sampling.

<FIG> illustrate a two way connector which is not within the scope of the present invention. It demonstrates that a further advantage of the aforesaid connector of the invention is that the same parts can be used to manufacture a two way connector with stop valve simply by omitting the one-way valve part <NUM> from the moulding of elastomeric material, or cutting away this part in a simple additional cutting step in order to switch manufacture to the two way connector. The parts here are designated by the same reference numerals for the corresponding parts in <FIG>, but commencing <NUM> instead of <NUM>. Also, because this version is a connector allowing fluid flow in both directions, then to conform to accepted colour coding within the UK health service, the outer body part <NUM> would be coloured white.

<FIG> illustrate further practical embodiments in accordance with aspects of the present invention. As shown, an integrated one-way and stop valve <NUM>, <NUM> is provided which may be identical to that in the preceding <FIG>. However, in contrast to the preceding embodiment of <FIG>, the connector body <NUM> in which the integrated valve <NUM>, <NUM> of elastomeric material is mounted is formed in one piece with a folding, snap fit closure <NUM>. In other respects, the final external form of the outer body <NUM> is the same as that of the connector body <NUM> shown it in <FIG>, namely with a male Luer lock connector <NUM> at one end and with external screw threads <NUM> on a female connector portion at the opposite end. So long as the dimensions of the exterior of the stop valve part <NUM> and the body <NUM> are accurately matched so as to provide circumferential sealing inside the externally threaded portion <NUM> and also between the end <NUM> of the valve and the facing surface in the housing, this configuration of connector body <NUM> has the added advantage of eliminating the need for any additional welding of parts or use of adhesive, therefore further simplifying and reducing the cost of the manufacturing process of the overall connector.

However, in a further embodiment, only slightly modified relative to <FIG>, and in accordance with a further aspect of the invention, only a stop valve <NUM> may be provided within the one-piece connector body <NUM> with the folding, snap fit closure <NUM>. In such embodiment, the one-way valve <NUM> will simply not be present and compared to the conjoined valve parts shown in <FIG>, it can simply be cut away, leaving only the stop valve <NUM>. Since the stop valve <NUM> provides the entire elastomeric material valve exterior having dimensions matched to be a close fit inside the housing <NUM>, the same advantages accrue here of assembly of only two parts, namely an outer body and a valve inside, and that additional steps of welding or use of adhesive in securing the housing by folding over and snap fitting the closure <NUM> may be unnecessary.

The invention is not restricted to the specific design details of any foregoing embodiments. For example, in other embodiments, the form of the strap <NUM> and the recess <NUM> in the one-piece moulding of the valves may be different to those in the illustrated embodiment. Indeed, these parts may be dispensed with in less favourable embodiments where reliability of sealing between the valve parts is not paramount. Also, in other embodiments the form of the one-way valve <NUM> may differ: it may not be a duck bill style of valve. Other variations in design detail are possible within the scope of the claims.

Throughout the description and claims of this specification, the word "comprise" means "including but not limited to", and it is not intended to (and does not) exclude other components.

Claim 1:
A medical connector comprising a connector body (<NUM>; <NUM>) having first and second apertures in fluid communication via a fluid flow conduit, a one-way valve (<NUM>) disposed in the body to allow fluid to flow from the first aperture, through the fluid flow conduit and out of the second aperture, but not to allow fluid to flow from the second aperture and through the fluid flow conduit to the first aperture, and a stop valve (<NUM>) which prevents fluid flowing out of the second aperture of the connector body unless a complementary end of a separate device engages the second aperture and opens the stop valve,
wherein inside the connector body, the one-way valve is fitted directly into an end of the stop valve part in a manner providing a fluid tight seal between these valve parts,
characterised in that the one-way valve (<NUM>) and the stop valve (<NUM>) are formed as parts of a single piece of elastomeric material, said parts being hingedly connected such that the one-way valve part is folded over and fitted directly into the end (<NUM>) of the stop valve part.