US 20070021721 A1
A medical valve has a body and a flexible element. The body includes a wall structure defining an internal cavity having an inside and an outside. The body also has a proximal end and a distal end. The proximal end has an opening sufficiently large to receive a tip of a delivery end of a medical implement which transfers fluid through the delivery end. The body has a fluid escape space in its wall structure. The flexible element is adapted to be moved into a compressed state upon insertion of the tip of the medical implement into the opening. The flexible element is sufficiently resilient to return to a decompressed state upon removal of the tip of the medical implement from the opening. The fluid escape space is in fluid communication with the outside of the cavity when the seal is in its compressed state.
1. A medical valve, comprising:
a body including a wall structure defining an internal cavity having an inside and an outside, said body also having a first end configured to receive a tip of a medical implement spout that expels fluid through said spout, said body having a fluid escape space in said wall structure;
a blunt member positioned within said cavity of said body, said blunt member having an inlet, and a conduit in communication with the hole that allows fluid to flow through said blunt member; and
a resilient seal positioned in said cavity, said seal adapted to assume a relatively compressed state upon insertion of the tip of the medical implement spout into said opening, said seal being sufficiently resilient to return to a decompressed state upon removal of the tip of the medical implement spout from said opening;
wherein said fluid escape space is open to the outside of said cavity when said seal is in said compressed state, when said tip of said medical implement spout is inserted into said opening, and when said seal is in said decompressed state.
2. The medical valve of
3. The medical valve of
4. A medical valve, comprising:
a body including a wall structure defining an internal cavity having an inside and an outside, said body also having a proximal end and a distal end, said proximal end having an opening sufficiently large to receive a tip of a delivery end of a medical implement configured to transfer fluid through said delivery end, said body having a fluid escape space in said wall structure;
a fluid conduit in fluid communication with said cavity of said body, said fluid conduit configured to allow fluid to flow through said medical valve; and
a resilient seal positioned in said cavity, said seal adapted to be moved into a compressed state that allows fluid to flow into said fluid conduit upon insertion of the tip of the medical implement into said opening, said seal being sufficiently resilient to return to a decompressed state that impedes flow of fluid into said fluid conduit upon removal of the tip of the medical implement from said opening;
wherein said fluid escape space is in fluid communication with the outside of said cavity when said seal is in said compressed state.
This application is a continuation of U.S. application Ser. No. 10/640,098, filed on Aug. 13, 2003, which was a continuation of U.S. application Ser. No. 10/004,561, filed on Dec. 4, 2001, which was a continuation of U.S. application Ser. No. 09/495,559, filed on Feb. 1, 2000, now U.S. Pat. No. 6,325,782, which was a continuation of U.S. application Ser. No. 09/055,646, filed on Apr. 6, 1998, now U.S. Pat. No. 6,019,748, which was a continuation of U.S. application Ser. No. 08/572,934, filed on Dec. 15, 1995, now U.S. Pat. No. 5,738,663.
1. Field of the Invention:
This invention relates to a closed, patient access system which automatically reseals after administering medication using a standard medical implement that directly connects with the system without the need of any intermediary needles, caps or adaptors. A two-way valve eliminating dead space is used which includes a seal which, upon being compressed by the medical implement, is pierced to open the valve and reseals upon being decompressed, maintaining a fluid tight seal even at high pressures and after repeated uses.
2. Background Discussion:
The manipulation of fluids for parenteral administration in hospital and medical settings routinely involves the use of connectors and adaptors for facilitating the movement of fluids between two points. Most fluid connectors and adaptors employ needles to pierce a septum covering sterile tubing or to pierce the septum of a medicament container of fluid. Fluid then passes from the container or fluid filled tubing into a syringe or second set of tubing. These connectors and adaptors often have mechanical or moving parts. Since the ready passage of fluids through the connectors and adaptors is often critical to patient survival, it is imperative that the connectors and adaptors function reliably and repeatedly. Adaptors and connectors that malfunction during use may be life-threatening. The more mechanical or moving parts such as springs and diaphragms, the more likely that they will function improperly. Improper functioning can result in the introduction of air embolisms into a patient. Thus, the fewer the mechanical parts, the more these connectors can be relied on and the better they will be accepted by the medical community.
Many connectors or valves, especially those employing several mechanical components, have a relatively high volume of fluid space within them. This “dead space” within the device prevents the accurate introduction of precise fluid volumes and provides an opportunity for contamination upon disconnection of the device. Connectors and adaptors often include valves that permit or interrupt the flow of fluid along the course of fluid travel. Several of those commonly in use employ metal needles to puncture sterile seals. Such connectors are generally designed to accommodate fluid flow in one direction. This means that the fluid line must have connectors and tube aligned in complementary directions. These connectors often require further manipulation if, for example, the valve is inadvertently assembled in a direction that will not facilitate fluid flow. These manipulations increase handling, thereby increasing both the risk of contamination and the amount of time required to establish the fluid connection.
Metal needles employed as part of connector devices often have through-holes placed at the tip of the needle. Connection of the valve with a flow line involves piercing the needle through a sealed septum. Through-holes placed at the needle tip can core the septum and release free particulates into the flow line. Such an event can prove fatal to a patient. Such through-holes may also become clogged easily with material from the septum. Moreover, the use of a needle with a sharp point may also cause deterioration of the septum.
Reusable connectors and adaptors are preferred for medical applications since components must often be added or removed from a fluid line connected to a patient. Reusable connectors, however, are difficult to keep sterile. Sometimes caps are employed to cover the connector to keep it sterile. Frequently, these caps are lost, or simply not used because they are not readily available when needed.
A closed, patient access system that is easy to use and employs only a valve device in communication with the patient that need not be capped or interconnected with the medical implement through a needle or adaptor, is swabbable, is sufficiently durable to maintain its function after several manipulations, and maintains a fluid-tight seal at high pressures, would be of great benefit to the medical community.
The valve of this invention has several features, no single one of which is solely responsible for its desirable attributes. Without limiting the scope of this invention as expressed by the claims which follow, its more prominent features will now be discussed briefly. After considering this discussion, and particularly after reading the section entitled, “Detailed Description of the Preferred Embodiments,” one will understand how the features of this invention provide its advantages, which include safety, reliable and repeatable performance, simplicity of manufacture and use, and provides long life without malfunction.
A preferred embodiment of a seal used in the present invention comprises a series of O-ring elements stacked together and connected to form a unitary structure. The O-ring elements have increasing diameters, with the smallest diameter element being adjacent the proximal end of the cavity. The O-ring element closest to the proximal end of the seal contacts the wall of the spike proximal the through-holes when the seal is in a decompressed state, thereby preventing fluid from leaking from the interior of the spike through the proximal opening in the housing. It is desirable that at least the next immediate O-ring element also be in contact with the spike proximate the through-holes. Such a design prevents fluid from applying enough pressure on the slit to force the slit open while the seal is in the decompressed state. With the preferred embodiment fluid may reside in the spike and between the spike and the seal distal the through-holes without opening the slit in the seal cap. The seal is designed so that if this fluid pushes the seal upwards slightly, lifting the first and second O-ring elements upwards and off the spike, the O-ring elements immediately distal the first and second elements move up and contact the spike so as to ensure that fluid does not flow through the seal cap and out of the valve. Maintaining this contact around the spike avoids having fluid pressure on the slit force the slit open, permitting the valve to leak.
In another feature of the present invention, the housing is provided with fluid escape space, such as a groove or channel, to permit fluid contained between the exterior of the seal and the housing to escape during compression of the seal. In one embodiment, the proximal end of the housing is provided with at least one groove extending from the proximal end of the housing to indentations contained within the housing. During the compression of the seal, fluid between the exterior of the seal and the housing travels in a proximal direction through the grooves and out of the valve through the proximal end of the housing. In another embodiment, a channel is provided as the fluid escape space through the side wall of the housing. As the seal is compressed, fluid between the exterior of the seal and the housing travels through the channel to the exterior of the valve. As discussed in greater detail below, providing a groove or channel to permit fluid between the exterior of the seal and the housing side wall to escape from the valve during compression of the seal, provides several advantages.
The preferred embodiments of this invention, illustrating all its features, will now be discussed in detail. These embodiments depict the novel and non-obvious methods and valves of this invention as well as the medical implement indicators and methods of use thereof, as shown in the accompanying drawing, which is for illustrative purposes only. This drawing includes the following Figures, with like numerals indicating like parts:
The term “proximal” is used to denote the end of the valve and other components at or near the spike tip 32 in
The valve is a closed, patient access system which automatically reseals after administering medication using a medical implement that directly connects with the system without the need of any intermediate needles, caps or adaptors. A two-way valve is employed utilizing a reusable seal that may be repeatedly pierced by an enclosed, protected spike rather than an exposed metal needle. The valve facilitates fluid, particularly liquid, transfer while maintaining sterility. The valve is easy to use and is capable of locking in place. After use, the valve is swabbed in the conventional manner with a suitable substance to maintain sterility. The design of the valve avoids accidental needle sticks. As will be discussed in detail below, the valve is useful as a medical connector or adaptor to enable liquid flow from a sealed container.
The first feature of the invention is that the valve has a body including a wall structure defining an internal cavity having a proximal end and a distal end. The cavity has an open space into which the seal is pushed, and preferably has a plurality of radial indentations in the wall structure that are adjacent the seal to accommodate the expansion of the seal upon compression. The proximal end has an opening sufficiently large to receive a delivery end of a medical implement which transfers fluid through the delivery end. In most applications, the delivery end of the implement is tapered inward so that the wall structure and the tapered delivery end fit snug against each other upon insertion of the delivery end into the opening. The proximal end of the cavity preferably is adapted to fit snug with an ANSI (American National Standards Institute, Washington, D.C.) standard end of the medical implement. Typically, the implement is a syringe, a connector or inlet/outlet of an IV set, or any one of a wide variety of conduits used in medical applications.
The second feature is that the spike has a tip with at least one hole located at or near the tip, and a passageway in communication with the hole that allows fluid to flow through this hole. Preferably, the hole is in a side of the spike adjacent the tip and is elongated, having a size of 18 gauge or greater. More than one hole is desirable for many applications, and three, symmetrically located holes inward of the proximal end are preferred. The spike is seated inside the cavity and the tip is embedded in the seal cap located at the proximal end of the seal. The tip of the spike is blunt and rounded so as to avoid deterioration of the seal from repeated penetration by the spike. The spike may include at least one rib which allows air to enter a space between the seal and the spike, thereby facilitating the sealing of the opening when the implement is removed. The spike may have a substantially conical shape, and the seal has a complementarily, substantially conical shaped cavity within it conforming to the shape of the spike.
The third feature is that the resilient seal is adapted to be moved into a compressed state upon insertion of the tip of the medical implement into the opening and returns to a decompressed state upon removal of the tip. The seal in the decompressed state has a section which fills essentially completely a portion of the cavity adjacent the opening. In the compressed state, the seal section is pushed by the delivery end of the medical implement away from the opening and into the cavity. This seal section, known as the seal cap, may have a pre-cut slit in which the proximal end of the spike is embedded. The delivery end of the implement and the seal are adapted to engage so that when the tip of the spike pierces the seal there is essentially no dead space between said delivery end and the seal. Consequently, a predetermined dosage amount of medication is transferred in its entirety to the patient using this invention, with none of the prescribed amount being collected in dead space in the valve. The delivery of an exact amount of medication may be critical in some situations when chemotherapeutic agents are being administered or small children are being treated.
As best shown in
In the first embodiment of the valve, the upper conduit 20 is adapted to receive the tip or nose 48 of an ANSI standard syringe 46 (see
The hollow spike 26 has a tapered conical shape, ending in a sharp, pointed tip 32. Preferably, along the length of the spike are raised, protruding ridges 30. These raised ridges 30 extend from the surface of the spike preferably between 0.2-2.0 mm. The ridges 30 are preferably aligned along the length of the spike as illustrated in
The seal 36 preferably has a seal cap 40 with a generally flat top surface 40 b, an outwardly tapered side wall 38, and a lower lip 42. Its interior is hollow to provide the conically shaped cavity 37 (
The base of the seal 36 has a width such that the seal lip 42 fits snugly into the annular cuff 28. The hollow interior or cavity 37 (
As best shown in
During use, the valve is designed to be adapted as a two-way valve. The orientation of the valve is independent to fluid flow and dependent on the preferred orientation of the preexisting connections. Thus, the valve can be used as a valve connector for an intravenous central or peripheral piggyback connector in either orientation. Parenteral fluid is delivered to patients through tubing such that the liquid flows from a container through a piercing element into the patient. The containers are frequently changed or additional fluid bottles are added. The valve disclosed herein is designed to interconnect medical implements along the route of fluid delivery to the patient. However, the valve is also useful in any environment in which a resealable fluid valve is desired. During use, a connector of the appropriate size is fitted over the inner conduit 18. Locking can be achieved by a Luer-Lock mechanism, a pressure fit or any other locking mechanisms known to those with skill in the art, as described above. Thus, in one example, fluid passes from the inner conduit 18 into the spike 26. However, fluid flow is locked in place by the seal 36.
Upon removal of the syringe from the spike 26, as shown in
Advantageously, the through-holes 34 are located relatively low on the spike 26. Thus, the through-holes 34 are sealed relatively early in the process as the seal 36 returns to its original configuration when the valve 10 is closed. In one preferred embodiment of the valve, the through-holes 34 are located 0.075″ below the spike tip 32 (see
A cover cap (not shown) can be supplied to fit over the upper conduit 20 as further protection for the seal surface between use. Such a cover cap, however, is not needed to maintain sterility since the seal 36 may be swabbed with a disinfectant after each use. The reversibility of the seal 36 makes the valve 10 particularly attractive as a connector valve to provide fluid communication between two fluid lines. Therefore, the valve provides for placing a first fluid line in communication with a second fluid line using the valve disclosed herein. The reversibility of the valve 10 permits multiple fluid lines to be successively added, for example, to a fluid line in direct communication with a patient's vein. Since the valve is easily sterilizable and sealable, fluid lines can be added and removed without disconnecting venous contact.
The valve 10 is preferably prepared from a hard plastic, such as ABS plastic, but it is additionally contemplated that the valve could be prepared from other medically inert materials known to those in the art. The spike element 24 is preferably prepared from the same material as the housing 12. However, a stronger material, such as a poly-carbonate material, may be desirous for the spike element 24 to enable it to pierce a variety of connecting septums and seals. One particular advantage of this valve is that it does not rely on the use of metal needles. This dramatically reduces the risk of skin puncture during use and manufacture. Further, the upper conduit 20 serves as a shield to the spike 26 such that skin contact with the spike 26 is further reduced. The spike 26 need only be strong enough to penetrate the seal cap 40, or if necessary, to pierce a connecting septum.
In the embodiment of the valve illustrated in
An important advantage of the valve 10 is that it has very little dead space, thus the volume of liquid entering into the valve 10 is substantially equivalent to the volume of fluid leaving the valve 10. Further, the total equivalent fluid volume of the valve is very small such that the volume of fluid flowing through the system in order to place the valve 10 in fluid communication with a medical implement such as a syringe 46 is substantially zero.
In another preferred embodiment of the valve, illustrated by
As depicted in
Often the ingredients housed in containers are those that can be lyophilized at purchase. Lyophilized ingredients require reconstitution before use. If the medicament requires reconstitution before use, then sterile water, saline, or other fluid can be introduced into the container before fluid is extracted. The two-way nature of the valve permits this without any special adaptation. After the syringe is removed, the adaptor valve 50 automatically seals. Subsequently, aliquots can be removed from the container by syringe or the like. Alcohol or other compatible surface sterilizing agents can be used to wipe the lip 62 and seal 64 before each use. Similar to the first valve embodiment, it is additionally contemplated that a cap can be provided to fit over the upper chamber lip 62 between uses.
The adaptor valve 50 can be adapted to function as a medicament adaptor for an intravenous container. In this case, the adaptor valve 50 is placed on a medicament container for intravenous delivery and attached via tubing to an intravenous feed. Thus, the adaptor valve 50 can be placed in fluid communication with a connector valve of
An alternative embodiment of the seal, a seal 36 a, is shown in
In an alternative embodiment of the seal, the seal 36 b is shown in connection with the valve 10 in
As shown in
Another alternative embodiment of the seal, a seal 36 d, is shown in
As mentioned above, preferably the seal 36 d has a precut slit 11 in the cap 92 lying along the longitudinal axis of the valve 10. The seal cap 92 has a unique configuration that insures that the slit 11 closes and is sealed upon withdrawal of a syringe (not shown) and reformation of the seal 36 d. It includes an enlarged, internal, pressure responsive member 200 which is integral with the seal cap 92. Between the proximal end of the side wall 150 and the member 200 is an annular space 102 which is filled with the fluid in the cavity 98. This fluid is under pressure, for example at the blood pressure of the patient to which the valve 10 is attached. Referring to
Preferably, there is a tear ring 104 integral with the member 200 along the perimeter of the internal surface the member 200, and a slight saucer-like depression 204 in the external surface of the seal. The pressure responsive element in the decompressed state closes any orifice in the seal 36 d to provide an essentially fluid-tight seal while in the decompressed state. The pressure responsive member 200 enables the valve to maintain a fluid-tight seal even at very high pressures sometimes experienced in medical applications, particularly when the valve 10 is connected to a patient's artery. The center of the member 200 and the annular space 102 are coaxial with the entryway 11 a to the orifice 11. The pressurized fluid fills the annular space 102 to apply pressure that compresses the member 200 to tightly close the entryway 11 a to the orifice 11. In a preferred valve embodiment the distance from the entryway 11 a to the proximal end of the seal cap 92 is from 0.500 to 0.075 inches and more preferably approximately 0.100 inch.
As best illustrated in
Another alternative embodiment of the valve 10 using the seal 36 d is shown in
Another preferred embodiment of the seal 36 h is shown in
As best shown in
Other components of the valve interact with the various embodiments of the seal in a similar fashion to their interaction with seal 36 of
In general, the closing of the valve 10 is provided not by the side wall of the seal 36 which immediately covers the through-holes 34, but by the seal cap 40, or seal cap 92 filling the proximal end of the cavity 98 and the opening 25 a. Thus, the seal caps 40 and 92 are sufficiently thick to reseal the opening 25 a effectively after valve closure. However, the seal caps 40 and 92 should also be sufficiently thin to allow them to readily return to the closed position. Preferably the thickness of the caps 40 and 92 ranges between 0.075 and 0.500 inch and more preferably may be approximately 0.100 inch.
The valve can be provided in a sterile and disposable form such that after its use in a given installation is exhausted, the device is discarded. However, as described above, in any given installation, the valve can be reused multiple times. Since the valve does not employ needles, there is little chance that the device will inadvertently cause skin puncture. Therefore, the extra precautions required for handling and disposing of needles is obviated. It will be apparent from the detailed description provided herein that the valve can provide for the elimination of nearly all needles used in the medical environment. With the use of the valve described above, the need for all needles except those that are directly input into a patient is, advantageously, eliminated.
The valve 10 is used to provide a closed, patient access system for transferring a predetermined amount of medication from a remote source to the patient. The valve 10 is connected by the distal end to the patient, for example, a vein or artery in fluid communication with the valve. Blood fills the valve, but the seal 36 d, for example, prevents any blood from leaking from the valve. The delivery end or nose 48 of the medical implement is inserted into the valve as depicted in
Another alternative embodiment of the seal, a seal 36 h, is shown in
Seal 36 h also has a precut slit 11 in seal cap 92 lying along the longitudinal axis of the seal 36 h. Slit 11 remains sealed when seal 36 h is in a decompressed state. As explained earlier, precutting the seal to provide slit 11 allows for more rapid decompression and reformation of the seal upon piercing by the spike. Unlike seal 36 d, however, seal cap 92 of seal 36 h is substantially solid without having any pressure responsive member as is employed in seal cap 92 for seal 36 d.
An alternative embodiment of the present invention using seal 36 h is shown in
Another feature of this embodiment is the arrangement of the spike 26 a with the seal 36 h when the seal 36 h is in a decompressed state. In this state, rounded tip 32 of spike 36 h is positioned to be embedded in slit entryway 11 a, while slit 11 remains closed to any fluid flow.
During medical applications, for example when the valve 10 is connected to a patient's artery, the patient's blood flows through the holes 34 in spike 26 a, filling the area in cavity 98 distal the second tire 100 b. Since the fluid residing between the first two tires, 100 a and 100 b, and between seal cap 92 and tire 100 a constitutes a very small volume, the fluid cannot exert enough pressure against the seal cap to open slit 11. Pre-cut seal cap 92 is designed to remain closed up to fluid pressure of 20 psi. Therefore, blood pressure will not open the valve 10.
Upon connection of the distal end of valve 10 with a patient's artery, however, as the blood pushes up against seal 36 h, the fluid may force seal cap 92 to move proximally, thereby also pushing the sidewall tires 100 in the proximal direction. This pressure may permit blood to flow past tires 100 a and 100 b to place pressure on the slit 11. However, due to increased fluid pressure, the tires immediately distal first and second tires 100 a and 100 b move proximally and contact the spike 26 a to take the original positions of tires 100 a and 100 b so as to ensure that a plurality of tires are always in contact with spike 26 a. Because the sidewall tires 100 of seal 36 h are designed to bow outward from the proximal to the distal end, the tires immediately distal tires 100 a and 100 b may not be in contact with spike 26 a when in their original position. However, as will be understood by those of skill in the art, if fluid flows through the spike 26 a, through-hole 34 and into cavity 98 of seal 36 h, forcing the seal 36 h to move in a proximal direction, tires distal the first tire 100 a and second tire 100 b will also move in a proximal direction and contact the spike 26 a proximally through-hole 34 strengthening the seal between the spike 26 a and the seal 36 h. That is, when fluid is not contained within the cavity 98 of the valve 10, only the first tire 100 a and second tire 100 b contact the spike 26 a. However, once fluid is introduced into the cavity 98 of the valve 10, the seal 36 h may travel in a proximal direction. If this occurs, tires directly distal second tire 100 b contact seal 26 a in addition to the first tire 100 a and second tire 100 b strengthening the seal between the seal 36 h and spike 26 a and preventing fluid from traveling through spike 26 a, through the through-hole 34 into the cavity 98 and past the tires 100 to exert pressure on the slit 11 in the seal cap 92 of seal 36 h.
An alternative embodiment of the housing, housing 12 a, is shown in
Provision of the fluid escape spaces provides the advantage of allowing any fluid residing in the space between the seal 36 h and the upper conduit 20 to exit the housing upon compression of the seal 36 h. Referring to
By providing grooves 303, 304 as fluid escape spaces, fluid present between the seal 36 h and the inner wall 305 of the upper conduit 20 of the housing 12 a may travel proximally through the grooves 303, 304 upon compression of the seal 36 h by a medical implement (not shown). As the fluid is expelled from the valve 10 through the grooves 303, 304 at the proximal end of the housing 12 a, the seal 36 h may compress normally without use of excessive force by a user of the valve 10.
Another alternative embodiment for the housing, housing 12 b, is shown in
As will be easily understood by those of skill in the art, a channel and groove may be incorporated in combination to assist in expelling fluid from the valve upon compression of the seal by a medical implement. For example, upon compression of the seal, fluid could travel through a groove proximally and thereafter through a channel in communication with the groove. The channel could be located distally the proximal end of the valve. Moreover, a single groove or channel may be utilized or multiple grooves or channels may be incorporated into the valve of the present invention as will be easily understood by those of skill in the art.
Lack of a channel or groove as discussed above, may result in deterioration of the seal 36 and prevent the seal cap 92 from being pushed completely below through hole 34. If the through-hole is not completely open, the patient will not be able to receive a constant flow rate of medication. In some situations, the delivery of an exact amount of medication at a predetermined rate may be critical for treatment, and, therefore, through-hole 34 must be completely open for passage of medication from the medical implement. Thee groove and/or channel ensures that the seal cap may be pushed distally the through-hole and that the seal may be compressed without any excessive force which may cause damage to the seal.