US20050222541A1 - Positive flow valve - Google Patents

Abstract

A closed system, spikeless, positive-flow valve device includes a body defining an internal cavity. At the proximal end of the body is an opening which is preferably sufficiently large to receive an ANSI standard tip of a medical implement. The valve includes a plastic, resilient silicon seal which fills the upper cavity and opening with an oval seal cap having a slit. The opening presses the oval seal cap to keep the slit closed in the decompressed state. The slit opens as the nose of the medical implement compresses the seal into the cavity and the seal cap is free from the opening. The housing also includes a fluid space which facilitates fluid flow between the medical implement and a catheter tip. The fluid space within the valve automatically and reversibly increases upon insertion of the medical implement into the cavity and decreases upon withdrawal of the medical implement, such that a positive flow from the valve toward the catheter tip is effected upon withdrawal of the medical implement, thereby preventing a flow of blood from a patient into the catheter when the medical implement is removed from the valve.

Description

• This application is a continuation of pending U.S. application Ser. No. 10/163,719, filed Jun. 5, 2002, which is a continuation of U.S. application Ser. No. 09/411,988, filed Oct. 4, 1999, now U.S. Pat. No. 6,428,52, which is a continuation of U.S. application Ser. No. 08/767,587, filed Dec. 16, 1996, now abandoned.
BACKGROUND OF THE INVENTION
• 1. Field of the Invention
• This invention relates generally to a medical valve, and in particular to a positive flow valve which, when connected between a medical implement and a catheter to facilitate fluid flow therethrough, induces a positive flow of fluid through a tip of the catheter from the valve upon disconnection of the medical implement, thereby eliminating the problem of blood-clogging or clotting in the catheter.
• 2. Description of the Related Art
• The manipulation of fluids for parenteral administration in hospitals and medical settings routinely involves the use of connectors and valves for facilitating the movement of fluids between two points. Fluid connectors and valves typically employ needles or luers to pierce a septum or seal covering sterile tubing or to pierce a septum or seal of a medicament container of fluid. Fluid then passes from the container or fluid-filled tubing into a syringe or second set of tubing. Since the ready passage of fluids through the connectors and valves is often critical to patient survival, it is imperative that the connectors and valves function reliably and repeatedly. Connectors and valves that malfunction during use may be life-threatening.
• Many connectors or valves, especially those employing several mechanical components, have a relatively high volume of fluid space within them. There is potential for the creation of a “dead space” (i.e. an increase in the fluid containment area which will cause fluid within the patient to be drawn therein) in the fluid space during removal or disconnection of the tubing or other medical implements such as conduits, syringes, IV sets (both peripheral and central lines), piggyback lines, and similar components which can be used in connection with a medical valve. Withdrawal of the medical implement creates a suction force which draws fluid back toward the valve in a phenomenon known as “backflash.” This is particularly troublesome in the case where the valve is connected through a catheter to a patient. A suction force is generated by the withdrawal of the medical implement which draws blood from the patient into the catheter. This blood clot and clog the catheter near its tip, rendering it inoperable, and may even result in a clot of blood in the patient, which may prove fatal. Attempts to avoid backflash by coating the inner surface of the catheter near its tip in order to prevent blood from sticking to the interior surfaces of the catheter and clogging it have not been successful.
• The risk of blood clogging of the catheter is significantly heightened where the inner diameter of the catheter is small (e.g., 27 gauge). These small catheters have the advantage, however, that they reduce the trauma and discomfort caused by insertion into a patient. Because these catheters have a very small passage therethrough, even a small suction force may draw sufficient amount of fluid back through a catheter toward the valve to introduce blood into the catheter tip, which blood may clog the catheter's passage. This back flow is hereinafter referred to as a negative flow.FIG. 1 shows an example of acatheter50 having a small portion near thetip52 that is inserted into the patient, and avalve54 connected between one end of the catheter and amedical implement56. The problem associated with the creation of “dead space” or a drawing of fluid from the catheter towards the valve is illustrated by this Figure. As illustrated therein, when the tip or nose of themedical implement56 is withdrawn from thevalve54, the space previously occupied by theimplement56 becomes “dead space.” This newly created space has a lower pressure than the fluid within the valve, catheter and patient, such that fluid is drawn into that space, and thus travels from the patient in the direction of the dead space. To avoid blood from being drawn into the catheter, a zero flow or a positive flow, defined as flow or fluid displacement directed from the valve through the catheter tip to the patient, must be effected at the time the medical implement is withdrawn. For a sufficient margin of safety, a positive flow toward the patient is desirable.
• To avoid negative flow or backflash, healthcare workers presently practice the method of disconnecting the valve and simultaneously transferring fluid through the catheter by manipulating the medical implement to induce positive flow. This method is clumsy and difficult, and may result in an inaccurate transfer of medicament.
• One way to induce a positive flow in the catheter is illustrated inFIGS. 2aand2b. Here, the proximal end of avalve180 is enclosed with a stylet or displacer182 upon withdrawal of the medical implement (not shown). Anelongated portion184 of thestylet182 takes up at least a portion of the fluid space, thereby reducing the volume of the fluid space, and may eliminate the dead space therein. Theelongated portion184, however, must be sufficiently long to displace more fluid than that volume of fluid which may be drawn from the catheter towards the valve by the withdrawal of the implement, and hence may be difficult to construct for proper performance. The use of thestylet182 further requires an additional step that may be overlooked by the nurse and thestylet182 may be misplaced or lost. In addition, this specific type ofvalve180 has many significant drawbacks, among them the fact that it does not have a seal with a swabbable surface that can be swabbed after each use for sterility.
SUMMARY OF THE INVENTION
• In accordance with the present invention there is provided a positive flow valve which is advantageously utilized between a catheter and another medical implement, and with which the flow of a fluid between the implement and catheter (and a patient within which the catheter is employed). The valve of this invention has several features, no single one of which is solely responsible for its desirable attributes.
• In general, the positive flow valve of the present invention has the attributes of safety, positive flow for eliminating dead space, reliable and repeatable performance, simplicity of manufacture and use, a seal for use in establishing fluid flow which need not be pierced with a sharp spike or cannula, suitability of high pressure applications, and employment of a valve that is swabbable after use to provide sterility and has a fluid-tight seal at high pressure.
• The present invention is a swabbable, needle-less, positive flow valve that has a fluid space which automatically expands upon insertion of a medical implement and contracts upon withdrawal of the medical implement. When the valve is connected to a catheter, it induces a positive flow from the valve to the catheter tip upon disconnection of the medical implement to avoid the potential problems of blood-clogging. 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 or spike sticks. The valve is particularly suited for applications with a catheter where it is desirable to avoid backflash, but may be used for other applications as well.
• Preferably, the valve includes a housing having a first end adapted for receiving one end of medical implement, and having a second end in communication with a catheter. The valve includes means for establishing a fluid flow path through the housing and between the medical implement and the catheter, and which is also useful in occluding the flow path through the housing and thereby preventing fluid flow between the medical implement and catheter.
• Preferably, this means comprises a seal movably positioned within the housing. The seal has a passage therethrough which defines, in at least one area, a fluid containment area. The seal has a first end adapted for engagement by the medical implement. In a first position, the passage through the seal is closed at its first end, and in a second position, when the medical implement is utilized to press the seal distally within the housing of the valve, the passage through the valve is opened.
• Most importantly, when the medical implement is utilized to press the seal distally and establish fluid flow therethrough, the fluid containment area therein increases in total volume, thereby retaining a fluid volume therein. When the medical implement is retracted from the valve, the seal returns to its position wherein the passage is closed at the proximal end thereof, and the volume of the fluid containment area is reduced. This reduction in fluid containment volume results in a volume of fluid being forced towards the catheter (i.e. a positive flow is established).
BRIEF DESCRIPTION OF THE DRAWINGS
• The preferred embodiments of this invention, illustrating all its features, will now be discussed in detail. These embodiments depict the novel and nonobvious method and valve of this invention shown in the accompanying drawings, which are for illustrative purposes only. The drawings include the following Figures, with like numerals indicating like parts:
• FIG. 1 is a schematic cross-sectional view of a valve forming a fluid connection between a syringe and a catheter.
• FIGS. 2aand2billustrate a prior art valve which includes a stylet having an elongated portion after use to induce a positive flow.
• FIG. 3 is a schematic cross-sectional view of a roller-clamp valve which may be manually activated to induce a positive flow through a catheter tip from the valve.
• FIG. 4 is a longitudinal cross-sectional view of the first embodiment of the positive-flow valve of this invention before compressing the seal.
• FIG. 5 is a longitudinal cross-sectional view similar toFIG. 4 showing the valve during compression of the seal.
• FIG. 6 is a longitudinal cross-sectional view of the second embodiment of the positive-flow valve of this invention before compressing the seal.
• FIG. 7 is a longitudinal cross-sectional view similar toFIG. 6 showing the valve during compression of the seal.
• FIG. 8 is a longitudinal cross-sectional view of the third embodiment of the positive-flow valve of this invention before compressing the seal.
• FIG. 9 is a longitudinal cross-sectional view similar toFIG. 8 showing the valve during compression of the seal.
• FIG. 10 is a longitudinal cross-sectional view of the fourth embodiment of the positive-flow valve of this invention before compressing the seal.
• FIG. 11 is a longitudinal cross-sectional view similar toFIG. 10 showing the valve during compression of the seal.
• FIG. 12 is a longitudinal cross-sectional view of the fifth embodiment of the positive-flow valve of this invention before compressing the seal.
• FIG. 13 is a longitudinal cross-sectional view similar toFIG. 12 showing the valve during compression of the seal.
• FIG. 14 is a longitudinal cross-sectional view of the sixth embodiment of the positive-flow valve of this invention before compressing the seal.
• FIG. 15 is a longitudinal cross-sectional view similar toFIG. 14 showing the valve during compression of the seal.
• FIG. 16 is a longitudinal cross-sectional view of the seventh embodiment of the positive-flow valve of this invention before compressing the seal.
• FIG. 17 is a longitudinal cross-sectional view similar toFIG. 16 showing the valve during compression of the seal.
• FIG. 18 is a longitudinal cross-sectional view of the eighth embodiment of the positive-flow valve of this invention before compressing the seal.
• FIG. 19 is a longitudinal cross-sectional view similar toFIG. 18 showing the valve during compression of the seal.
• FIG. 20 is a longitudinal cross-sectional view of the ninth embodiment of the positive-flow valve of this invention before compressing the seal.
• FIG. 21 is a longitudinal cross-sectional view similar toFIG. 20 showing the valve during compression of the seal.
• FIG. 22 is a longitudinal cross-sectional view of the tenth embodiment of the positive-flow valve of this invention before compressing the seal.
• FIG. 23 is a longitudinal cross-sectional view similar toFIG. 22 showing the valve during compression of the seal.
• FIG. 24 is a longitudinal cross-sectional view of the eleventh embodiment of the positive-flow valve of this invention before compressing the seal.
• FIG. 25 is a longitudinal cross-sectional view similar toFIG. 24 showing the valve during compression of the seal.
• FIG. 26 is a longitudinal cross-sectional view of the twelfth embodiment of the positive-flow valve of this invention before compressing the seal.
• FIG. 27 is a longitudinal cross-sectional view similar toFIG. 26 showing the valve during compression of the seal.
• FIG. 28 is a longitudinal cross-sectional view of the thirteenth embodiment of the positive-flow valve of this invention before compressing the seal.
• FIG. 29 is a longitudinal cross-sectional view similar toFIG. 28 showing the valve during compression of the seal.
• FIG. 30 is a longitudinal cross-sectional view of the fourteenth embodiment of the positive-flow valve of this invention before compressing the seal.
• FIG. 31 is a longitudinal cross-sectional view similar toFIG. 30 showing the valve during compression of the seal.
• FIG. 32 is a longitudinal cross-sectional view of an alternative seal with a side wall formed with circular tires.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
• The Applicant has recognized that a roller clamp may be used to induce a positive flow in a medical valve. The use of a roller clamp in amedical valve190 to create a positive flow upon disconnection of a medical implement (not shown) is illustrated inFIG. 3. The roller-clamp valve190 is activated manually by sliding anexternal switch192 to push aroller194 againsttubing196 which connects a medical implement198 and a catheter (not shown) to cause a positive pressure therein, thereby creating a positive flow through the catheter tip (not shown). The flow through thetubing196 can be opened by sliding theswitch192 in the reverse direction.
• Thisvalve190, however, has the same disadvantage of requiring an additional step of operation as does the valve with a stylet illustrated inFIGS. 2aand2b, and also does not include a seal having a swabbable surface. Furthermore, the size of theroller194 must be sufficiently large to induce a displacement of fluid within the tube which is greater than the amount of fluid which may be drawn by the vacuum force (so as to generate a positive flow), which may require a bulky valve that is hard to operate.
First Embodiment
• FIGS. 4 and 5 illustrate a first embodiment of avalve210 in accordance with the present invention. In general, thisvalve210 includes a valve body orhousing212, asupport member214, aseal216 defining aninner cavity218, a pair ofclam shells220aand220b, and aspring222. These components are assembled, as depicted inFIG. 4, without the need for a spike element. Theinner cavity218 forms an expandable fluid space inside thevalve210. As discussed below, theclam shells220a/220bare constructed to cause the volume of the fluid space to expand or increase upon insertion of a medical implement and to contract or decrease upon withdrawal of the medical implement.
• The body orhousing212 has anupper conduit226 near aproximal end228, desirably with acircular opening230 that is adapted to receive the medical implement. Aside wall portion232 is preferably tapered to cooperate with theclam shells220a/220b. Thebody212 has anupper ledge234 formed between theproximal end228 and theside wall portion232. There is desirably a threaded portion on thehousing212 adjacent thecircular opening230 in the top of theupper conduit226, as best seen inFIG. 4. Note that “proximal” is used to denote the end of thevalve210 and other components at or near thebody opening230, while “distal” is used to denote the opposite end of the valve.
• In the first embodiment, theupper conduit226 is adapted to receive the tip ornose236 of an ANSIstandard syringe238, as shown in phantom inFIG. 5. It is, however, contemplated that the outer diameter of theupper conduit226 can be of any size to accommodate the attachment of other connector devices thereto. Advantageously, the proximal end of theupper conduit226 can be equipped with a locking mechanism to facilitate locking of thevalve210 to a variety of connector devices. For example, referring toFIG. 4, the threaded portion of thehousing212 are preferably provided such that thehousing212 can be locked into any compatible Luer-Lock device known to those with skill in the art. Thehousing212 of the first embodiment according to this invention includes conventional Luer-Lock threads240 on the outer diameter of theupper conduit226.
• Thesupport member214 has at its distal end theinner conduit242 which may be connected to a terminal end of a catheter (not shown). Thesupport member214 serves as a support and attachment device for theseal216 by holding theseal216 in place inside theinternal cavity244 of thehousing212. Theinner conduit242 andinner cavity218 of theseal216 present a continuous passageway for fluid during use.
• Theseal216 is prepared from a resilient material that is flexible, inert, and impermeable to fluid, such as silicon. Theseal216 has aseal cap248 with a generally flattop surface250, ashoulder252, aside wall254, and abase256. Theside wall254 advantageously is comprised ofwall portions258 which deform in an accordion-like fashion and assist in the reformation of theseal216 to close thehousing opening230 upon withdrawal of thesyringe238. During compression of theseal216, thewall portions258 expand outwardly in the radial direction. The interior of theseal216 is hollow to provide theinner cavity218, as best seen inFIG. 4. There are preferably gaps between thewall portions258 which facilitate deformation and reformation of theseal216. Theshoulder252 engages theupper ledge234 provided in theupper conduit226 of thehousing212 such that theupper ledge234 confines the movement of theshoulder252 toward theopening230 to prevent theseal216 from being blown through theopening230 under high pressure in theinner cavity218 of theseal216.
• Theseal cap248 reseals thevalve210 at theopening230, with thetop surface250 of theseal216 approximately flush with or slightly above or below theopening230 upon removal of the medical implement238. Preferably, theseal cap248 substantially fills theopening230 in the top of theupper conduit226. After assembly, thetop surface250 of theseal cap248 is essentially flush with theopening230, so that theseal cap248 can be swabbed with alcohol or other disinfectant without leakage of the disinfectant into thevalve210. Therefore, it is preferable that thetop surface250 be exposed so that it may be swabbed with a disinfectant.
• To provide a fluid-tight seal at theopening230 and to eliminate the need for a spike element to induce fluid flow upon insertion of a medical implement, theseal cap248 has a unique shape and includes aprecut slit259, also having a unique shape. Theseal cap248 desirably has an oval or elliptical shape with a major axis having a length larger than the inner diameter of thecircular opening230 such that theoval seal cap248 substantially fills theopening230 in the top of theupper conduit226 in the decompressed state. The precut slit259 in theseal cap248 is squeezed shut by thecircular opening230 in the decompressed state, as seen inFIG. 4. In its resting state, the precut slit259 is open. During compression of theseal216 by insertion of a medical implement such as thesyringe238, as illustrated inFIG. 5, the precut slit259 returns to its resting state and opens, as theseal cap248 is allowed to stretch in the portion of theupper conduit226 which has a larger inner diameter. Fluid is thus allowed to pass through theslit259. Note that the terms “compressed state” and “decompressed state” are used conveniently to refer to compression and decompression of theseal216 by insertion and withdrawal of the medical implement238 along the longitudinal axis of theseal216. The terms do not relate to the radial compression of theseal cap248 by theopening230 of thehousing212.
• To further assist in creating a fluid-tight seal in the decompressed state, theseal216 ofFIG. 4 advantageously includes the enlarged, internal, pressureresponsive member260 which is integral with theseal cap248. The pressureresponsive member260 enables thevalve210 to maintain a fluid-tight seal even at very high pressures sometimes experienced in medical applications, particularly when thevalve210 is connected to a patient's artery.
• As shown inFIGS. 4 and 5, theclam shells220a/220bare desirably identical pieces disposed opposite one another symmetrically inside thevalve body212. They are preferably made of a firm material such as a hard plastic. The external surface264a/264bof eachclam shell220a/220bis tapered to cooperate with the taperedside wall portion232 of thehousing212, and is configured to slide along theside wall portion232 during compression and decompression. Theinternal surfaces266a/266bof theclam shells220a/220bcooperate with one another to squeeze a portion of theseal side wall254, preferably adjacent theshoulder252, to form aconstricted portion267 of theseal216. The proximal ends268a/268bof theclam shells220a/220bengage theshoulder252 of theseal216 to facilitate movement of theclam shells220a/220bwith the compression of theseal216. Theinternal surfaces266a/266bpreferably are shaped to cause theconstricted portion267 to be substantially circular. In this embodiment, eachinternal surface266a/266bhas a semi-circular, longitudinal groove that squeezes theseal216.
• Thespring222 is disposed between the distal ends of theclam shells220a/220band thebase256 of theseal216, but desirably ahard retaining disk270 is provided adjacent thebase256 of theseal216 to provide better support for thespring222 and theseal216. In the decompressed state shown inFIG. 4, thespring222 may be relaxed or be in slight compression to exert a force on theseal216 through theclam shells220a/220bto keep theseal216 closed. During insertion of thesyringe238, thespring222 is compressed and stores potential energy from the compression, as illustrated inFIG. 5. Upon withdrawal of thesyringe238, thespring222 releases the potential energy and pushes theclam shells220a/220bproximally to close theseal216, as shown inFIG. 4. Thespring222 is preferably not attached or bonded to either theclam shells220a/220bor theretaining disk270 for ease of assembly. AlthoughFIGS. 4-5 show ahelical spring222, any suitable spring known to those of skill in the art may be used.
• Theseal216 is desirably relaxed longitudinally in the decompressed state (FIG. 4), and compressed longitudinally in the compressed state (FIG. 5). Alternatively, theseal216 may be stretched longitudinally in tension by thespring222 in the decompressed state and be relaxed or slightly compressed longitudinal in the compressed state. Thebase256 of theseal216 advantageously fits snugly and securely into aannular groove274 provided in theretaining disk270 and anannular groove276 provided in thesupport member214. Theannular grooves274,276 form a locking mechanism to support and secure theseal216 within thecavity244 of thehousing212.
• To illustrate valve activation,FIG. 5 shows the compressed state of thevalve210 upon insertion of thesyringe238. A medical implement other than a syringe as known to those of skill in the art may be used. Thenose236 of thesyringe238 is placed on theseal cap248 inside theopening230 of thehousing212. The application of pressure on thesyringe238 creates pressure on theseal cap248, and the resulting downward pressure compresses theseal216. This pushes theseal cap248 away from thecircular opening230 and toward the lower portion of thehousing cavity244 which has a larger inner diameter, thereby allowing the precut slit259 to open. The downward movement is facilitated by the compression of thespring222 which stores the potential energy of compression and by the gaps between thewall portions258 of theside wall254 of theseal216. Fluid is now able to flow into thesyringe238, or vice versa, depending on whether fluid is to be withdrawn from the patient or medication injected into the patient.FIG. 5 shows thevalve210 opened by insertion of thenose236 of thesyringe238 into theopening230. For intravenous applications, thevalve210 can be oriented in the position diagramed inFIGS. 4 and 5, or it can be rotated 180′ such that fluid flows in the opposite direction.
• In the compressed state shown inFIG. 5, theinner cavity218 of theseal216 generally contracts (becomes shorter) as compared to the decompressed state shown inFIG. 4. Theconstricted portion267 of theinner cavity218, defined by theclam shells220a/220b, however, expands (becomes larger) in volume when theseal216 is in the compressed state. This results from a movement of theclam shells220a/220bapart from one another as they slide along the taperedside wall232 of thehousing212. The amount of general contraction of theseal216 in relation to the amount of expansion of theconstricted portion267 during compression determine whether thevalve210 generates a positive, negative, or zero flow upon decompression, as discussed below.
• Upon removal of thesyringe238 from theupper conduit226, as shown inFIG. 4, theseal216 is free to move toward its decompressed state, and theclam shells220a/220bare pushed proximally toward theopening230. The movement causes a general expansion of the inner cavity218 (i.e., the cavity increases in length), but causes a contraction (i.e., reduction in size) of the volume of theconstricted portion267 of theseal216. If the volume change associated with the contraction of theconstricted portion267 equals the volume change associated with the expansion of theinner cavity218, the fluid space or inner cavity will have zero flow. If the increase in volume associated with the expansion of theinner cavity218 is greater than the reduction in volume associated with the contraction of theconstricted portion267, there will be a net gain in fluid space, resulting in an undesirable negative flow toward thevalve210 through, e.g., a catheter tip (not shown). If the reduction in volume associated with the contraction of theconstricted portion267 is greater than the increase in volume associated with the expansion of theinner cavity218, there will be a desirable positive flow from thevalve210 through the catheter tip (not shown). Thus, for thevalve210 to be a positive-flow valve requires that the clam shells be configured to allow greater expansion of the constricted portion267 (i.e., an increase in fluid volume in that area of the seal216) than the general contraction volume change associated with the expansion of theinner cavity218 of theseal216 upon compression and, hence, greater contraction (i.e., decrease in fluid volume within that area of the seal) of theconstricted portion267 than the general expansion (i.e., increase in fluid volume in that area of the seal) of theseal216 upon decompression. In other words, for thevalve210 to induce positive flow upon disconnection of the medical implement238 therefrom, the total fluid volume within thevalve210 must decrease. In the instant case, this decrease in fluid volume is effectuated by causing the fluid volume within the seal to decrease as between its compressed (when syringe attached) and uncompressed (when syringe detached) states. This reduction or decrease in available fluid volume within thevalve210 causes fluid to flow towards the catheter/patient, preventing blood from being drawn into the catheter.
• That thevalve210 is advantageously configured to be a positive-flow valve210 eliminates any dead space during decompression of theseal210 as thesyringe238 is withdrawn, as illustrated inFIG. 4. Furthermore, as thesyringe238 is withdrawn, theslit259 remains open until the very end, i.e., until theseal cap248 is squeezed by thecircular opening230 at the top of theupper conduit226. This further assists in eliminating dead space and avoiding backflash. This feature is particularly advantageous in the case where thevalve210 is connected through a catheter to a patient, because it prevents blood from being drawn into the catheter and clogging it. This invention therefore eliminates a significant risk by solving the problem of backflash.
• As theseal216 is free to move to its decompressed state, it essentially fills theopening230. The ability of theseal216 to return to its original shape and be deformed in its decompressed state is determined by the resiliency of the material used to prepare theseal216. Advantageously, the ability of theseal216 to return to its decompressed state is facilitated by thespring222 and the gaps between thewall portions258 of theseal216. The ability of theseal216 to deform reversibly and return to its decompressed state is particularly useful because (1) it immediately stops fluid flow through thevalve210, and (2) it maintains sterility of the valve.
• The ability of theseal216 to return reversibly to its decompressed state permits reuse of thevalve210. Following disconnection, and before reuse, thesurface250 of theseal cap248 is essentially flush with theopening230 of thehousing212. Thus, thisflush surface250 can advantageously be sterilized with alcohol or other surface-decontaminating substances. Thesupport member214 andbody212 advantageously shield both connections from the surrounding environment to protect the sterility of the connection.
• A cover cap (not shown) can be supplied to fit over theupper conduit226 as further protection for thesurface250 of theseal cap248 when not in use. Such a cover cap, however, is not needed to maintain sterility since theseal216 may be swabbed with a disinfectant before and/or after each use. Reversibility of theseal216 makes thevalve210 particularly attractive as a connector valve to provide fluid communication between two fluid lines. Therefore, the present invention provides for placing a first fluid line in communication with a second fluid line using thevalve210 disclosed herein. The reversibility of thevalve210 permits multiple fluid lines to be successively added, for example, to a fluid line in direct communication with a patient's vein. Since thevalve210 is easily sterilized and sealable, fluid lines can be added and removed without disconnecting venous contact of the catheter.
• Thevalve body212 andsupport member214 are preferably prepared from a hard plastic, but it is additionally contemplated that thevalve210 could be prepared from other medically inert materials known to those skilled in the art. Another feature of this invention is that it relies neither on a needle nor on a spike in order to establish fluid flow through the valve. This completely eliminates the risk of skin puncture or fear of puncture during use and manufacture. It also eliminates coring of theseal216 by a spike element and all the risks associated therewith. Further, the fluid flow rate is not limited by the size of a through passage in a needle or spike, as is the case in some prior art valves.
• As shown inFIG. 4, another feature of the invention is that theupper ledge234 confines the movement of theshoulder252 toward theopening250 to prevent theseal216 from being blown through theopening230 under high pressure in thecavity218. This makes thevalve210 particularly suited for high pressure applications.
Second Embodiment
• In a second embodiment of the present invention illustrated inFIGS. 6 and 7, thevalve310 includes a valve body orhousing312, asupport member314, askirt316, aseal318, aresilient member320, and a pair ofclam shells322a/322b. Thehousing312 is desirably similar to thehousing212 ofFIG. 4 and has a taperedside wall324.
• Referring toFIGS. 6 and 7, the second embodiment of thevalve310 has a bell-shapedskirt316. Theskirt316 has anannular ring328 which is disposed toward aninner conduit330 of thesupport member314. Theskirt316 creates a shield for theinner conduit330. Thisinner conduit330 is preferably cylindrical in shape and slightly tapered. The inner conduit may be connected to a terminal end of a catheter (not shown), which has an opposite, open end that is generally inserted into a patient. Thesupport member314 serves as a support and attachment device for theseal318 by holding theseal318 in place inside thehousing312.
• Thesupport member314 also serves as a support and attachment device for theskirt316. As best seen inFIG. 6, thesupport member314 has anedge portion332 which engages aledge334 of theskirt316 in assembly. This attachment secures theskirt316 in place. Theskirt316 desirably includes a Luer-Lock portion336 that enables thevalve310 to be removably attached to, for example, a fluid line or catheter connected to a patient. It is noted that thevalve310 in this embodiment includes askirt316 separate from thehousing312 for ease of assembly. A different embodiment can provide a unitary member which replaces thehousing312 andskirt316. It is therefore contemplated that such an embodiment would fall within the scope of this invention.
• Theseal318 is similar to theseal210 ofFIG. 4. Theseal318 is also preferably silicon and has asimilar seal cap340 with aprecut slit342,shoulder344, and pressureresponsive member348. These components serve the same function as those of theseal210. Instead of a side wall formed withwall portions258, theseal318 has aside wall350 that is generally circular cylindrical and has adistal portion352 that is sized to be slip-fitted with theproximal end354 of theinner conduit330 of thesupport member314. During compression of theseal318, theside wall350 simply slides over theproximal end354 of theinner conduit330, forming a fluid-tight seal therewith. Theseal318 defines aninner cavity358 above theproximal end354 of theinner conduit330. Theinner cavity358 forms an expandable fluid space inside thevalve310. Theinner conduit330 andinner cavity358 comprise aligned hollow tubes in fluid communication with each other when the precut slit342 of theseal318 opens during compression of theseal310.
• Similar in form and function to theclam shells220a/220bofFIGS. 4 and 5, theclam shells322a/322bare constructed to cause an increase in fluid space upon insertion of a medical implement into thevalve310 and a decrease in fluid space upon withdrawal of the medical implement such as asyringe362 partially shown in phantom inFIG. 7. Theinternal surfaces364a/364bof the clam shells desirably have longitudinal grooves that cooperate with one another to squeeze a portion of theseal side wall350 to form aconstricted portion366 thereof.
• Instead of thespring222 inFIG. 4, the second embodiment employs theresilient member320 disposed between theclam shells322a/322band thesupport member314. Theresilient member320 advantageously is inert and impermeable to fluid such as silicon, and includeswall portions368 which deform in an accordion-like fashion and assist in the reformation of theseal318 to close thehousing opening370 upon withdrawal of thesyringe362. Theresilient member320 thus is similar in construction with and serves the same function as thespring222 of theseal210 ofFIGS. 4 and 5. It is contemplated that a spring (not shown) similar to thespring222 ofFIG. 4 may be used in place of theresilient member320, as may other suitable structures known to those of skill in the art.
• As shown inFIGS. 6 and 7, theresilient member320 has abase346. The base346 fits snugly and securely within anannular groove374 provided in thehousing312 and anannular groove377 provided in thesupport member314, as shown inFIG. 6. Theannular grooves376,377 hence form a locking mechanism to support and secure theresilient member320 within thehousing312. Theshoulder344 engages an upper ledge382 provided in anupper conduit384 of thehousing312 such that the upper ledge382 confines the movement of theshoulder344 toward theopening370 to prevent theseal318 from being blown through theopening370 under high pressure in theinner cavity358 of theseal318.
• Theresilient member320 is desirably relaxed or slightly compressed longitudinally in the decompressed state (FIG. 6), and compressed longitudinally in the compressed state (FIG. 7). Theresilient member320 is desirably not attached or bonded to either of theclam shells322a/322bor thehousing312.
• FIG. 7 illustrates compression andFIG. 6 illustrates decompression during valve activation. In the compressed state, thesyringe362 is placed on theseal cap340 inside theopening370 of thehousing312, and the application of pressure on thesyringe362 creates pressure on theseal cap340. The downward pressure pushes theseal cap340 away from thecircular opening370 and toward the distal lower portion of thehousing312 which has a larger inner diameter, thereby allowing the precut slit342 to open. Theside wall350 slides over theproximal end354 of theinner conduit330, and theresilient member320 deforms in an accordion-like manner, storing potential energy of the compression. Fluid is able to flow into thesyringe362, or vice versa, depending on whether fluid is to be withdrawn from the patient or medication injected into the patient.
• The compression of theseal318 shown inFIG. 7 generally causes a contraction or reduction in the volume of theinner cavity358 of theseal318. Thevalve310 has a net gain in volume of theinner cavity318, however, because the general reduction in volume within theinner cavity358 is less than an increase in volume within theconstricted portion366 of theinner cavity358 defined by theclam shells322a/322b. The expansion results from the movement of theclam shells322a/322bapart from one another during compression, facilitated by the taperedside wall324 of thehousing312.
• FIG. 6 illustrates the valve after withdrawal of thesyringe362. Theseal318 returns to its decompressed state and essentially fills theopening370, and theclam shells322a/322bare pushed proximally toward theopening370 by theresilient member320. Because of the contraction of theinner cavity358 at theconstricted portion366 by theclam shells322a/322b, there is a net loss or reduction in fluid space, resulting in a positive flow from thevalve310 through, e.g., a catheter tip (not shown). The positive-flow valve310 advantageously eliminates any dead space during decompression of theseal318. This is further assisted by theseal318 with theslit342 remaining open until the very end, i.e., until theseal cap340 is squeezed by theupper conduit384.
• In addition, thevalve310 can be reused because theseal318 can return reversibly in the decompressed state. Theseal surface340 is also swabbable for sterility. Other features of thevalve310 are discussed previously in connection with the first embodiment of this invention and will not be repeated.
Third Embodiment
• As shown inFIGS. 8 and 9, a third embodiment of thevalve410 of the present invention comprises a valve body orhousing412, asupport member414, aflexible tubing416, aseal418, aring member420, a pair ofclam shells422a/422b, and aspring424. Theflexible tubing416 may be connected to a catheter (not shown) and, together with theseal418, defines aninner cavity426. Theinner cavity426 forms an expandable fluid space of thevalve410. Theclam shells422a/422bdesirably are substantially the same as theclam shells220a/220bofFIG. 4 and are constructed to cause the fluid space within thevalve410 to increase upon insertion of a medical implement and to decrease upon withdrawal of the medical implement such as asyringe428 partially shown in phantom inFIG. 9. Thehousing412 is desirably similar to thehousing212 ofFIG. 4.
• Thesupport member414 has ahollow center430 which supports the flexible tubing, and aproximal end432 which encloses adistal end434 of thehousing412. Thesupport member414 desirably locks onto thehousing412 via any method known to those of skill in the art. Theproximal end432 of thesupport member414 supports thespring424, which in turn supports theclam shells422a/422bandseal418.
• Theseal418 is prepared from a resilient material that is flexible, inert, and impermeable to fluid, such as silicon. Referring toFIG. 8, theseal418 is substantially similar to theseal210 ofFIG. 4, with a portion of theside wall438 cut off near theshoulder440 region. As a result, theside wall438 of theseal418 is substantially shorter than theside wall254 of theseal210 inFIG. 4. Adistal end442 of theside wall254 is attached, preferably by adhesive, to aproximal end444 of theflexible tubing416. Thedistal end442 abuts thering member420 which is disposed between theseal418 and theclam shells422a/422band attached at itsinner surface446 to a portion of thetubing416, desirably also by adhesive. Other suitable means of attachment may be used. Thering member420 is desirably made of polycarbon.
• Theclam shells422a/422bdesirably form a sliding contact at their proximal ends with thering member420 for ease of assembly, but may alternatively be affixed to thering member420 by adhesive or similar means. Theclam shells422a/422bare desirably the same as theclam shells220a/220bofFIG. 4, having taperedexternal surfaces450a/450bto cooperate with the taperedside wall portion452 of thehousing412 for sliding and groovedinternal surfaces454a/454bthat cooperate with one another to squeeze a portion of thetubing416 to form aconstricted portion456.
• Thespring424 is substantially the same as thespring222 ofFIG. 4 and serves the same function, being disposed between the distal ends of theclam shells422a/422band theproximal end432 of thesupport member414. In the decompressed state shown inFIG. 8, thespring424 may be relaxed or in slight compression to exert a force on theseal418 through theclam shells422a/422bto keep theslit466 in theseal cap460 closed. During insertion of thesyringe428, thespring424 is compressed and stores potential energy from the compression, as illustrated inFIG. 9. Upon withdrawal of thesyringe428, thespring424 releases the potential energy and pushes theclam shells422a/422bproximally to close theseal418, as shown inFIG. 8. Thespring424 is preferably not attached or bonded to either theclam shells422a/422bor thesupport member414 for ease of assembly. Thespring424 can be a helical spring or any other suitable spring known to those with skill in the art.
• FIG. 9 shows the compressed state of thevalve410 upon insertion of thesyringe428. In the compressed state, thesyringe428 is placed on theseal cap460 inside theopening464 of thehousing412 and the application of pressure on thesyringe428 creates pressure on theseal cap460. The downward pressure pushes theseal cap460 away from thecircular opening464 and toward the distal end of thehousing412, which has a larger inner diameter, thereby allowing the precut slit466 of theseal cap460 to open. Theresilient tubing416 and theclam shells422a/422balso move distally as thespring424 deforms in compression, storing potential energy. Fluid is able to flow into thesyringe428, or vice versa, depending on whether fluid is to be withdrawn from the patient or medication injected into the patient.
• The compression of theseal418 shown inFIG. 9 generally causes a reduction in the volume of theinner cavity426 formed by theseal418 andtubing416. However, because of an expansion of theconstricted portion456 defined by theclam shells422a/422ban increase in fluid volume is created which is greater than the general reduction in fluid volume within theinner cavity426, thevalve410 has a net gain in fluid volume. The increase in fluid volume results from the movement of theclam shells422a/422bapart from one another during seal compression, facilitated by the taperedside wall452 of thehousing412 and resiliency of thetubing416.
• FIG. 8 illustrates thevalve410 after withdrawal of thesyringe428. Theseal418 returns to its decompressed state and essentially fills theopening464, and theclam shells422a/422bare pushed proximally toward theopening464 by thespring424. Because of the contraction of theinner cavity426 at theconstricted portion456 by theclam shells422a/422b, there is a net loss in fluid space, resulting in a positive flow from thevalve410 through, e.g., a catheter tip (not shown). The positive-flow valve410 advantageously eliminates any dead space during decompression of theseal418. This is further assisted by theseal418, with theslit466 remaining open until the very end, i.e., until theseal cap460 is squeezed byupper conduit470.
• In addition, thevalve410 can be reused because theseal418 can return reversibly to the decompressed state. Theseal surface472 is also swabbable for sterility. Other features of thevalve410 are discussed previously in connection with the earlier embodiments of this invention and will not be repeated.
Fourth Embodiment
• A fourth embodiment of the present invention is illustrated inFIGS. 10 and 11. As illustrated therein, avalve510, comprises a valve body orhousing512, asupport member514, askirt516, a retainingmember518, aseal520, a pair ofclam shells522a/522b, and aresilient member524. Thevalve510 has several features that are the same or similar to those of thevalve310 ofFIGS. 8 and 9, having a similarresilient member524 andclam shells522a/522b. Theclam shells522a/522bhaveinternal surfaces526a/526bthat cooperate with one another to squeeze a portion of theseal side wall528 to form aconstricted portion530 thereof.
• Theseal510 is preferably made of silicon and has aseal cap532 with aprecut slit534,shoulder536, lower lip538, and pressureresponsive member540 that are similar to theseal210 ofFIG. 4. These components serve the same function as those of theseal210. Theside wall528 may be formed with ringedwall portions258, as in theseal210, butFIG. 4 shows theside wall528 that is generally circular cylindrical. Theseal520 defines aninner cavity542 which forms an expandable fluid space inside thevalve510. During compression of theseal520, theside wall528 deforms outwardly into a circumferential cusp orbulge544 in the unconstricted region between theclam shells522a/522band thesupport member514. Theside wall528 returns to its decompressed shape upon decompression of theseal520. Theseal520 is desirably relaxed longitudinally in the decompressed state (FIG. 10), and compressed longitudinally in the compressed state (FIG. 11). Alternatively, theseal520 may be stretched longitudinally in tension by theresilient member524 in the decompressed state and be relaxed or slightly compressed longitudinal in the compressed state.
• Referring toFIG. 10, theskirt516 is a bell-shaped skirt that is similar to theskirt316 ofFIG. 8. Theskirt516 creates a shield for aninner conduit548 of thesupport member514. Theinner conduit548 may be connected to a terminal end of a catheter (not shown) which has an open end that is generally inserted into a patient. Thesupport member514 serves as a support and attachment device for theseal520 by holding theseal520 in place inside thehousing512.
• Thesupport member514 also serves as a support and attachment device for theskirt516. Similar to thevalve310 ofFIG. 8, thesupport member514 shown inFIG. 10 has anedge portion550 which engages aledge552 of theskirt516 in assembly. This attachment secures theskirt516 in place. Theskirt516 desirably includes a Luer-Lock portion554 that enables thevalve510 to be removably attached to, for example, a fluid line or catheter connected to a patient.
• The retainingmember518 is desirably provided to secure the lower lip538 of theseal520 and support theresilient member524. The retainingmember518 is held inside thehousing512 by thesupport member514, and is provided for ease of assembling thevalve510. The retainingmember518 has anannular groove556, and thesupport member514 has anannular groove558. Theannular grooves556,558 form a locking mechanism to support and secure theseal520 within thehousing512 by engaging the lower lip538 snugly with thegrooves556,558. It is noted that a different embodiment may provide a unitary member which replaces thesupport member514 and the retainingmember518. It is therefore contemplated that such an embodiment would fall within the scope of this invention.
• FIG. 11 illustrates compression andFIG. 10 illustrates decompression during valve activation. In the compressed state, a medical implement such as thesyringe562 partially shown in phantom is placed on theseal cap532 inside theopening564 of thehousing512, and the application of pressure on thesyringe562 creates pressure on theseal cap532. The downward pressure pushes theseal cap532 away from thecircular opening564 and toward the lower portion of thehousing512, which has a larger inner diameter, thereby allowing the precut slit534 to open. Theside wall528 deforms outwardly at the unconstricted region into acircumferential cusp544, and theresilient member524 deforms in an accordion-like manner, storing potential energy of the compression. Fluid is able to flow into thesyringe562, or vice versa, depending on whether fluid is to be withdrawn from the patient or medication injected into the patient.
• The compression of theseal520 shown inFIG. 11 generally causes a reduction in the fluid volume of theinner cavity542 of theseal520. Thevalve510 has a net gain in volume of theinner cavity542, however, because the general reduction in volume within theinner cavity542 is less than the increase in volume within theconstricted portion530 as defined by theclam shells522a/522band of thecusp544 at the unconstricted region of theseal520.
• FIG. 10 illustrates thevalve510 after withdrawal of thesyringe562. Theseal520 returns to its decompressed state and essentially fills theopening564, and theclam shells522a/522bare pushed back up toward theopening564 by theresilient member524. Because of the contraction of theinner cavity542 of theseal520, there is a net loss in fluid space, resulting in a positive flow from thevalve510 through, e.g., a catheter tip (not shown). The positive-flow valve510 advantageously eliminates any dead space during decompression of theseal520. This is further assisted by theseal520, with theslit534 remaining open until the very end, i.e., until theseal cap532 is squeezed by thecircular opening564 at the top of theupper conduit570.
• In addition, thevalve510 can be reused because theseal520 can return reversibly in the decompressed state. The seal surface572 is also swabbable for sterility. Other features of thevalve510 are discussed previously in connection with the earlier embodiments of this invention.
Fifth Embodiment
• FIGS. 12 and 13 show afifth embodiment valve610 in accordance with the present invention, thevalve610 comprising a valve body orhousing612, aseal614, aring member616, and aspring618. Thehousing612 is similar to thehousing212 ofFIG. 4, with acircular opening620, and atapered side wall622, but may have a straight side wall instead. Theseal614 is similar to theseal318 ofFIG. 8, having a substantiallycylindrical side wall624 and defining aninner cavity626 which forms an expandable fluid space inside thevalve610. Theside wall624 may have different and variable thickness (not shown). The components are dimensioned and configured to cause the fluid space to expand upon insertion of a medical implement and to contract upon withdrawal of the medical implement such as asyringe630 partially shown in phantom inFIG. 13. The distal portion of theseal614 is connected to a fluid line such as a catheter (not shown), and may be secured to the housing by means known to those with skill in the art, such as by the use of a support member (not shown) similar to thesupport member214 shown inFIG. 15.
• Thering member616 is desirably anannular disk616 made of a hard plastic and disposed between ashoulder634 of theseal614 and aproximal end636 of thespring618. Thering member616 serves as a constraint for theseal614 during compression and efficiently transfers the compressive force to thespring618, assisting in the deformation of theseal614. During decompression, thering member616 efficiently transfers the spring force to theseal cap638 of theseal614 to close theopening620. Although thering member616 facilitates the deformation and reformation of theseal614, it is not necessary for theseal614 to work. In that case, thespring618 will contact theseal cap638 directly.
• Thespring618 is substantially the same as thespring222 ofFIG. 4 and serves the same function, being disposed between thering member616 and adistal end642 of thehousing612. In an alternative embodiment, thedistal end642 may be a separate component from thehousing612 for ease of assembly. In the decompressed state shown inFIG. 12, thespring618 may be relaxed or be in slight compression to exert a force on theseal614 through thering member616 to keep theseal614 closed. During insertion of thesyringe630, thespring618 is compressed and stores potential energy from the compression, as illustrated inFIG. 13. Upon withdrawal of thesyringe630, thespring618 releases the potential energy and pushes thering member616 to close theseal616 as shown inFIG. 12. Thespring618 is preferably not fixed with either thering member616 or thedistal end642 of thehousing612 for ease of assembly. Thespring618 can be a helical spring or any other suitable spring known to those with skill in the art.
• Theside wall624 of theseal614 is constrained by thering member616 andhousing612, and is substantially relaxed in the decompressed state. During compression of theseal614, theside wall624 bulges in the unconstrained region between thering member616 and thedistal end642 of thehousing612, causing an increase in the fluid space within thevalve610. Theside wall624 returns to its decompressed shape upon decompression of theseal614. Alternatively, theside wall624 may be stretched in tension by thespring618 in the decompressed state and goes through a relaxed position before deforming under compression to its bulged condition.
• FIG. 13 illustrates compression andFIG. 12 illustrates decompression during valve activation. In the compressed state, thesyringe630 is placed on theseal cap638 inside theopening620 of the housing and the application of pressure on thesyringe630 creates pressure on theseal cap638. The downward pressure pushes theseal cap638 and thering member616 away from thecircular opening620 and toward the lower portion of thehousing612 which has a larger inner diameter, thereby allowing the precut slit646 of theseal cap638 to open. Theside wall624 deforms outwardly and bulges at the unconstricted region, as thespring618 is compressed, storing potential energy of the compression. Fluid is able to flow into thesyringe630, or vice versa, depending on whether fluid is to be withdrawn from the patient or medication injected into the patient. The compression of theseal614 shown inFIG. 13 results in a net gain in volume of the inner cavity.
• FIG. 12 illustrates thevalve610 after withdrawal of thesyringe630. Theseal614 returns to its decompressed state and essentially fills theopening620, and thering member616 is pushed back up toward theopening620 as thespring618 releases its potential energy. Because of the contraction of theinner cavity626 of theseal614, there is a net loss in fluid space, resulting in a positive flow from thevalve610 through, e.g., a catheter tip (not shown). The positive-flow valve610 advantageously eliminates any dead space during decompression of theseal614. This is further assisted by theseal614 with theslit646 remaining open until the very end, i.e., until theseal cap638 is squeezed by thecircular opening620 at the top of theupper conduit650 of thehousing612.
• In addition, thevalve610 can be reused because theseal614 can return reversibly in the decompressed state. Theseal surface652 is also swabbable for sterility. Other features of thevalve610 are discussed previously in connection with the earlier embodiments of this invention.
Sixth Embodiment
• A sixth embodiment of avalve710 is illustrated inFIGS. 14 and 15. Thevalve710 comprises a valve body orhousing712 and aseal714. Thehousing712 has anupper conduit716 near a proximal end with acircular opening718 that is preferably adapted to receive a medical implement. Aside wall portion720 is protruded to facilitate deformation of theseal714. Adistal end724 of thehousing712 forms a lower passage726 (partially shown) which supports and constrains adistal portion728 of theseal714, and is connected, for example, to a fluid line such as a catheter (not shown). Alternatively, a support member (not shown) may be used to detachably lock onto thehousing712 and support theseal714, such as those shown inFIG. 4 (214) orFIG. 12 (514).
• Theseal714 is generally similar to theseal614 ofFIGS. 12 and 13, and has a substantially cylindrical side wall721, although theside wall732 may have a slight bulge733 as shown inFIG. 14. It defines aninner cavity734 which forms an expandable fluid space inside thevalve710. In the decompressed state, theseal714 is constrained by theupper conduit716 andlower passage726 of thehousing712, and is substantially relaxed in the decompressed state. The components are dimensioned and configured to cause the fluid space to expand or increase upon insertion of the medical implement and to contract or decrease upon withdrawal of the medical implement such as thesyringe730 partially shown in phantom inFIG. 15. During compression of theseal714, theside wall732 bulge in the unconstrained region between theupper conduit716 andlower passage726 and thebulge738 is substantially round. Theside wall732 return to its decompressed shape upon decompression of theseal714.
• FIG. 15 illustrates compression andFIG. 14 illustrates decompression during valve activation. In the compressed state, thesyringe730 is placed on theseal cap742 of theseal714 inside theopening718 of thehousing712 and the application of pressure on thesyringe730 creates pressure on theseal cap742. The downward pressure pushes theseal cap742 away from thecircular opening718 and toward the protrudedportion720 of thehousing712 which has a larger inner diameter, thereby allowing the precut slit746 of theseal cap742 to open. Theside wall732 deforms outwardly and bulges at theunconstricted region738, storing potential energy of the compression. Fluid is able to flow into thesyringe730, or vice versa, depending on whether fluid is to be withdrawn from the patient or medication injected into the patient. The compression of theseal714 shown inFIG. 15 generates a net gain in volume of the inner cavity.
• FIG. 14 illustrates thevalve710 after withdrawal of thesyringe730. Theseal714 returns to its decompressed state and essentially fills theopening718. Because of the contraction of theinner cavity734 of the seal, there is a net loss in fluid space, resulting in a positive flow from thevalve710 through, e.g., a catheter tip (not shown). The positive-flow valve710 advantageously eliminates any dead space during decompression of theseal714. This is further assisted by theseal714 with theslit746 remaining open until the very end, i.e., until theseal cap742 is squeezed by thecircular opening718 at the top of theupper conduit716.
• In addition, thevalve710 can be reused because theseal710 can return reversibly in the decompressed state. Theseal surface748 is also swabbable for sterility. Other features of thevalve710 are discussed previously in connection with the earlier embodiments of this invention.
Seventh Embodiment
• FIGS. 16 and 17 illustrate avalve710 in accordance with a seventh embodiment of the present invention, thevalve756 comprising a valve body orhousing758 and aseal760 that are substantially the same as thehousing712 and seal714 ofFIGS. 14 and 15, with adistal portion762 of theseal760 connected to a fluid line such as a catheter (not shown). Theseal760, however, is configured to deform upon compression into a diamond-shapedcusp764 instead of around bulge738 as illustrated inFIGS. 14 and 15. This type of construction may facilitate deformation and reformation of theseal760, and may be more easily formed. The valve activation of this embodiment is virtually identical to that inFIGS. 14 and 15, except for the deformed shape of theseal side wall770. It is contemplated, therefore, that a seal that may deform into a variety of shapes other than round and diamond shapes to achieve positive flow may be employed, as long as the it is dimensioned and configured to cause the fluid space of the valve to expand upon insertion of a medical implement and to contract upon withdrawal of the medical implement such as thesyringe774 partially shown in phantom inFIG. 28.
Eighth Embodiment
• As illustrated inFIGS. 18 and 19, aneighth embodiment valve810 of the present invention is similar to the embodiments shown inFIGS. 14-17. Thevalve810 also includes ahousing812 having aninternal cavity814 with anupper conduit816, and aseal818 disposed inside theinternal cavity814 and having aninner cavity820 that defines a fluid space. Thehousing812 has adistal end824 which supports aside wall826 of theseal818. Adistal portion828 of theseal818 is connected to a fluid line such as a catheter (not shown). The pressure at theinner cavity820 of theseal818 is P1. Between thehousing812 and theseal818 is anenclosed pressure chamber832 at pressure P2. The valve activation utilizes the pressure difference between P2 in thepressure chamber832 and P1 in theinner cavity820 of theseal818.
• Upon insertion of a medical implement such as asyringe836 shown in phantom inFIG. 19, the pressure at theinner cavity820 of theseal818 increases from P1 to P3 and the fluid space inside theseal818 expands from the decompressed state ofFIG. 18. The expansion of the fluid space results primarily from a difference in pressure between P3 and P2. Thisvalve810 is particularly advantageous in the case where theside wall826 of theseal818 deforms without storing substantial potential energy. For instance, theside wall826 of theseal818 may deform without substantial resistance or resiliency such as a membrane, or the seal is not constrained longitudinal by thedistal portion824 of thehousing812 and may slide in and out of theinternal cavity814 of thehousing812 through thedistal end824.
• FIG. 19 illustrates compression andFIG. 18 illustrates decompression during valve activation. In the compressed state, thesyringe836 is placed on theseal cap838 of theseal818 inside theopening840 of thehousing812 and the application of pressure on the syringe creates pressure on theseal cap838. The downward pressure pushes theseal cap838 away from thecircular opening840 and toward the lower portion of thehousing812 which has a larger inner diameter, thereby allowing the precut slit844 of theseal cap838 to open. The entry of the fluid causes the pressure at theinner cavity814 of theseal812 to increase to P3. As a result, theside wall826 deforms outwardly and bulges at theunconstricted region848. Potential energy is stored in the change in pressure differential between theinner cavity820 and thepressure chamber832. Theside wall826 of theseal818 need not deform and store energy, but may do so. Fluid is able to flow into thesyringe836, or vice versa, depending on whether fluid is to be withdrawn from the patient or medication injected into the patient. The compression of theseal818 shown inFIG. 19 causes a net gain or increase in fluid volume within the inner cavity.
• FIG. 18 illustrates thevalve810 after withdrawal of thesyringe836. Theseal818 returns to its decompressed state and essentially fills theopening840, and the pressure in theinner cavity820 returns to P1 and releases the potential energy. Because of the contraction of theinner cavity820 of theseal818, there is a net loss in fluid space, resulting in a positive flow from thevalve810 through, e.g., a catheter tip (not shown). The positive-flow valve810 advantageously eliminates any dead space during decompression of theseal818. This is further assisted by theseal818 with theslit844 remaining open until the very end, i.e., until theseal cap838 is squeezed by thecircular opening840 at the top of theupper conduit816.
• In addition, thevalve810 can be reused because theseal818 can return reversibly in the decompressed state. Theseal surface854 is also swabbable for sterility. Other features of thevalve810 are discussed previously in connection with the earlier embodiments of this invention.
Ninth Embodiment
• A ninth embodiment of avalve910 comprising ahousing912, asupport member914, askirt916, aseal918, and a scissor-like cross member920, is depicted inFIGS. 20 and 21. Thehousing912 has anupper conduit924 with acircular opening926. Thesupport member914 has aninner conduit928 which is connected to a fluid line such as a catheter (not shown). Theseal918 has aside wall930 desirably formed of alternatingwall portions932 and defines aninner cavity934 which forms an expandable fluid space inside thevalve910. Thecross member920 is dimensioned and configured to assist in causing the fluid space to expand upon insertion of a medical implement and to contract upon withdrawal of the medical implement such as thesyringe936 partially shown in phantom inFIG. 21.
• Thecross member920 has twolongitudinal member940 attached together which rotates with respect to one another, and is desirably made of a hard material such as a hard plastic. Thecross member920 is disposed at aconstricted portion942 of theseal918 within theinner cavity934 with thelongitudinal members940 preferably substantially disposed vertically. The ends944 of thelongitudinal members940 are desirably attached to theside wall930 as shown inFIG. 20. Thelongitudinal members940 rotate to a substantially horizontal orientation upon compression by the insertion of thesyringe936 as shown inFIG. 21. This rotation is referred to as the deformation of thecross member920. Thelongitudinal members940 may be attached to rotate freely with respect to one another. Alternatively, thelongitudinal members940 may be spring-loaded or attached such that they rotate under a rotational force but reform to their relaxed position upon release of the force. Upon withdrawal of thesyringe936 as shown inFIG. 20, thelongitudinal members940 return to the substantially vertical positions, referred to as the reformation of thecross member920. Thelongitudinal members940 are desirablylongitudinal plates940 with sufficient width to expand theconstricted portion942 of theseal918 in the substantially horizontal position but not so wide that they impedes flow therethrough. Alternatively, they may contain holes (not shown) through which fluid can pass.
• FIG. 21 illustrates compression andFIG. 20 illustrates decompression during valve activation. In the compressed state, thesyringe926 is placed on theseal cap950 of theseal918 inside theopening926 of thehousing912 and the application of pressure on thesyringe936 creates pressure on theseal cap950. The downward pressure pushes theseal cap950 away from thecircular opening926 and toward the lower portion of thehousing912 which has a larger inner diameter, thereby allowing the precut slit952 ofseal cap950 to open. Theside wall930 of theseal918 deforms in an accordion-like manner, and thecross member920 deforms and opens up the constricted portion922 of theseal918, storing potential energy of the compression. Fluid is able to flow into thesyringe936, or vice versa, depending on whether fluid is to be withdrawn from the patient or medication injected into the patient. The compression of theseal918 and deformation of thecross920 shown inFIG. 21 generally causes a contraction of the volume of theinner cavity934 of theseal918. Thevalve910 has a net gain in volume of theinner cavity934, however, because the general contraction of theinner cavity934 is less than by the expansion of theconstricted portion942 pushed apart by thecross member920. The expansion results from the movement of thelongitudinal members940 of thecross member920 during compression.
• FIG. 20 illustrates thevalve910 after withdrawal of thesyringe936. Theseal918 returns to its decompressed state and essentially fills theopening926, and thecross member920 reforms to allow the constrictedregion942 of theseal918 to narrow. Because of the contraction of theinner cavity934 at theconstricted portion942, there is a net loss in fluid space, resulting in a positive flow from thevalve910 through, e.g., a catheter tip (not shown). The positive-flow valve910 advantageously eliminates any dead space during decompression of theseal918. This is further assisted by theseal918 with theslit952 remaining open until the very end, i.e., until theseal cap950 is squeezed by thecircular opening926 at the top of theupper conduit924.
• In addition, thevalve910 can be reused because theseal918 can return reversibly in the decompressed state. Theseal surface960 is also swabbable for sterility. Other features of thevalve910 are discussed previously in connection with the earlier embodiments of this invention.
Tenth Embodiment
• FIGS. 22 and 23 illustrate avalve1010 in accordance with a tenth embodiment of the present invention, thevalve1010 comprising a valve body orhousing1012, a support member1014 (partially shown), aseal1016, aring member1018, aresilient reel1020, and a scissor-like cross member1022. Thesupport member1014 has an inner conduit (not shown) which is connected to a fluid line such as a catheter (not shown). Theseal1016 has aseal cap1028 withslit1030,shoulder1032, and pressureresponsive member1034.
• Thering member1018 forms a sliding contact with adistal end1036 of theseal1016 and is preferably made from a hard plastic. Thering member1018 desirably has ashoulder1038 which is constrained by aledge1040 of thehousing1012 in the upward direction. The distal end of thering member1018 contacts anupper flange1044 of theresilient reel1020 and facilitates transfer of the compressive force due to insertion of a medical implement to cause deformation of thereel1020. Thereel1020 is made from a material that is flexible, inert, and impermeable to fluid, such as silicon. It has alower flange1046 that is supported and secured by thesupport member1014 and acentral body portion1048 that is substantially cylindrical. Theseal1016,ring member1018, andresilient reel1020 define aninner cavity1050 which forms an expandable fluid space inside thevalve1010.
• Thecross member1022 is substantially the same of thecross member920 ofFIGS. 20 and 21 and is dimensioned and configured to assist in causing the fluid space to increase upon insertion of a medical implement and to decrease upon withdrawal of the medical implement such as thesyringe1054 partially shown in phantom inFIG. 23. Thecross member1022 has twolongitudinal members1056 rotatably attached together. Thecross member1022 is disposed adjacent thecentral body portion1048 of thereel1020 within theinner cavity1050 with thelongitudinal members1056 preferably pointed toward the vertical direction and desirably attached to thecentral body portion1048 at its fourends1058 as shown inFIG. 22. Thelongitudinal members1056 rotate to a substantially horizontal orientation upon compression by the insertion of thesyringe1054 as shown inFIG. 23. This rotation is referred to as the deformation of thecross member1022. Thelongitudinal members1050 may be attached to rotate freely with respect to one another. Alternatively, thelongitudinal members1056 may be spring-loaded or attached such that they rotate under a rotational force but reform to their relaxed position upon release of the force. Upon withdrawal of thesyringe1056 as shown inFIG. 22, thelongitudinal members1056 return to the substantially vertical positions, referred to as the reformation of thecross member1022. The longitudinal members1026 are desirablylongitudinal plates1056 with sufficient width to open up thecentral body portion1048 of thereel1020 in the substantially horizontal position but not so wide that they impedes flow therethrough. Alternatively, they may contain holes (not shown) through which fluid can pass.
• FIG. 23 illustrates compression andFIG. 22 illustrates decompression during valve activation. In the compressed state, thesyringe1054 is placed on theseal cap1028 inside theopening1062 of thehousing1012 and the application of pressure on thesyringe1054 creates pressure on theseal cap1028. The downward pressure pushes theseal cap1028 away from thecircular opening1062 and toward the lower portion of thehousing1012 which has a larger inner diameter, thereby allowing theprecut slit1030 to open. Thering member1018 moves toward thesupport member1014 and compresses theresilient reel1020. Theupper flange1044 of theresilient reel1020 is pushed by thering member1018 toward thelower flange1046. Thecentral body portion1048 bulges outwardly as thecross member1022 deforms, storing potential energy of the compression. Fluid is able to flow into thesyringe1054, or vice versa, depending on whether fluid is to be withdrawn from the patient or medication injected into the patient.
• The compression of theseal1016 and deformation of thecross1022 shown inFIG. 23 generally causes a reduction in the volume of the inner cavity of theseal1016. Thevalve1010 has a net gain in volume of theinner cavity1050, however, because the expansion of thecentral body portion1048 of the flexible reel120 causes an increase in fluid volume which reduction resulting in is greater than the general contraction of theinner cavity1050. The expansion results from the movement of thelongitudinal members1056 of thecross member1022 to open up thecentral body portion1048 of theresilient reel1020 during compression.
• FIG. 22 illustrates thevalve1010 after withdrawal of thesyringe1054. Theseal1016 returns to its decompressed state and essentially fills theopening1062, and thecross member1022 reforms to allow thecentral body region1048 of theresilient reel1022 to narrow. Because of the contraction of theinner cavity1050 at thecentral body portion1048, there is a net loss in fluid space, resulting in a positive flow from thevalve1010 through, e.g., a catheter tip (not shown). The positive-flow valve1010 advantageously eliminates any dead space during decompression of theseal1016. This is further assisted by theseal1016 with theslit1030 remaining open until the very end, i.e., until theseal cap1028 is squeezed by thecircular opening1062 at the top of theupper conduit1066 of the housing.
• In addition, thevalve1010 can be reused because theseal1016 can return reversibly in the decompressed state. Theseal surface1068 is also swabbable for sterility. Other features of thevalve1010 are discussed previously in connection with the earlier embodiments of this invention.
Eleventh Embodiment
• An eleventh embodiment of avalve1110 in accordance with the present invention is illustrated inFIGS. 24 and 25, and comprises a valve body orhousing1112 and aseal1114. Thehousing1112 has anupper conduit1116 near a proximal end with acircular opening1118 that is preferably adapted to receive a medical implement such as asyringe1120 partially shown in phantom inFIG. 25. Thehousing1112 has a lower conduit1124 (partially shown) near a distal end which is connected to a fluid line such as a catheter (not shown). Disposed between theupper conduit1116 andlower conduit1124 are protruded right and leftside walls1126a,1126bconnected to resilientribbed portions1128a,1128bwhich allow theside walls1126a,1126bto be stretched outwardly and reform inwardly in a substantially horizontal direction. Aside from the resilientribbed portions1128a,1128b, the rest of thehousing1112 is desirably made of a firm material such as a hard plastic.
• Theseal1114 is generally similar to theseal318 ofFIG. 6 with asimilar shoulder1132,seal cap1134, and pressureresponsive element1136. Thecylindrical side wall350 ofFIG. 6, however, is replaced with aspreader1140, which includes twolegs1142a,1142bthat extend from theshoulder1132 outwardly atdistal ends1144a,1144bthat bear against the protruded right and leftside walls1126a,1126b, as best seen inFIG. 24. Thedistal end1144amay be attached to the protrudedside wall1126a, and thedistal end1144bmay be attached to the protrudedside wall1126b, by adhesives or other available means. Aninner cavity1150 is formed by theseal1114 and adistal portion1152 of thehousing1112, and defines a fluid space of thevalve1110. During compression of theseal1114, thespreader1140 extends further outwardly and pushes the protrudedside walls1126a,1126boutwardly. Theseal1114 andhousing1112 are configured and dimensioned to assist in causing the fluid space to expand upon insertion of the medical implement1120 and to contract upon withdrawal of the medical implement1120.
• FIG. 25 illustrates compression andFIG. 24 illustrates decompression during valve activation. In the compressed state, thesyringe1120 is placed on theseal cap1134 inside theopening1118 of thehousing1112 and the application of pressure on thesyringe1120 creates pressure on theseal cap1134. The downward pressure pushes theseal cap1134 away from thecircular opening1118 and toward the lower portion of thehousing1112 which has a larger inner diameter, thereby allowing theprecut slit1156 oft he sealcap1134 to open. Thespreader1140 extends outwardly, stretching the resilientribbed portions1128a,1128band pushing the protruded right and leftside walls1126a,1126bof thehousing1112 outwardly, storing potential energy of the compression. Fluid is able to flow into thesyringe1120, or vice versa, depending on whether fluid is to be withdrawn from the patient or medication injected into the patient. The compression of theseal1114 and deformation of thespreader1140 shown inFIG. 36 results in a net gain in volume of theinner cavity1150.
• FIG. 24 illustrates thevalve1110 after withdrawal of thesyringe1120. Theseal1114 returns to its decompressed state and essentially fills theopening1118, and thespreader1140 and resilientribbed portions1128a,1128breform to allow the protruded right and leftside walls1126a,1126bto move inwardly. Because of the contraction of theinner cavity1150, there is a net loss in fluid space, resulting in a positive flow from thevalve1110 through, e.g., a catheter tip (not shown). The positive-flow valve1110 advantageously eliminates any dead space during decompression of theseal1114. This is further assisted by theseal14 with theslit1156 remaining open until the very end, i.e., until theseal cap1134 is squeezed by thecircular opening1156 at the top of theupper conduit1116.
• In addition, thevalve1110 can be reused because theseal1114 can return reversibly in the decompressed state. Theseal surface1160 is also swabbable for sterility. Other features of thevalve1110 are discussed previously in connection with the earlier embodiments of this invention.
Twelfth Embodiment
• Atwelfth embodiment valve1210 is illustrated inFIGS. 26 and 27, and comprises a valve body orhousing1212, a support member1214 (partially shown), aseal1216, aring member1218, and aresilient reel1226. Thehousing1212,support member1214, andring member1218 are substantially the same as those shown inFIGS. 22 and 23. Thehousing1212 has anupper conduit1224 with acircular opening1226. Thesupport member1214 has an inner conduit (not shown) which is connected to a fluid line such as a catheter (not shown). Thedistal end1228 of thering member1218 contacts anupper flange1232 of theresilient reel1220 and facilitates transfer of the compressive force due to insertion of a medical implement such as a syringe to cause deformation of thereel1220. Thereel1220 further includes acentral body portion1234 and alower flange1236 that is desirably supported and secured by thesupport member1214.
• Theseal1216 is similar to theseal1114 ofFIGS. 24 and 25, and has asimilar seal cap1240 withslit1242,shoulder1244, and pressureresponsive member1246. Theseal1246 has aspreader1250 that extends from theshoulder1244 outwardly and forms a circulardistal ring1252 that bears against thecentral body portion1234 of theresilient reel1220, as best seen inFIG. 26. Thedistal ring1252 may be attached to thecentral body portion1234 by adhesives or other available means. Aninner cavity1254 is formed by theseal1216 and adistal portion1256 of the resilient reel, and defines a fluid space of thevalve1210. During compression of theseal1216, thespreader1250 extends further outwardly and pushes thecentral body portion1234 of theresilient reel1220 outwardly. Theseal1216 andresilient reel1220 are configured and dimensioned to assist in causing the fluid space to increase upon insertion of a medical implement and to decrease upon withdrawal of the medical implement such as thesyringe1260 partially shown in phantom inFIG. 27.
• FIG. 27 illustrates compression andFIG. 26 illustrates decompression during valve activation. In the compressed state, thesyringe1260 is placed on theseal cap1240 inside theopening1226 of thehousing1212 and the application of pressure on thesyringe1260 creates pressure on theseal cap1240. The downward pressure pushes theseal cap1240 away from thecircular opening1226 and toward the lower portion of thehousing1212 which has a larger inner diameter, thereby allowing theprecut slit1242 to open. Thering member1218 moves toward thesupport member1214 and compresses theresilient reel1220. Theupper flange1232 of theresilient reel1220 is pushed by thering member1214 toward thelower flange1236. Thecentral body portion1234 bulges outwardly as thespreader1250 deforms and pushes thecentral body portion1234 outwardly, storing potential energy of the compression. Fluid is able to flow into thesyringe1260, or vice versa, depending on whether fluid is to be withdrawn from the patient or medication injected into the patient.
• The compression of theseal1216 and deformation of thespreader1250 and reel1220 shown inFIG. 27 causes an increase in volume of theinner cavity1254 because of the expansion of thecentral body portion1234 of theflexible reel1220. The expansion results from the movement of thespreaders1250 to open up thecentral body portion1234 of theresilient reel1220 during compression.
• FIG. 26 illustrates thevalve1210 after withdrawal of thesyringe1260. Theseal1216 returns to its decompressed state and essentially fills theopening1226, and thespreader1250 reforms to allow thecentral body region1234 of theresilient reel1220 to narrow. Because of the contraction of theinner cavity1254 at thecentral body portion1234, there is a net loss in fluid space, resulting in a positive flow from thevalve1210 through, e.g., a catheter tip (not shown). The positive-flow valve1210 advantageously eliminates any dead space during decompression of theseal1216. This is further assisted by theseal1216 with theslit1242 remaining open until the very end, i.e., until theseal cap1240 is squeezed by thecircular opening1226 at the top of theupper conduit1224.
• In addition, thevalve1210 can be reused because theseal1216 can return reversibly in the decompressed state. Theseal surface1266 is also swabbable for sterility. Other features of thevalve1210 are discussed previously in connection with the earlier embodiments of this invention.
Thirteenth Embodiment
• Athirteenth embodiment valve1310 in accordance with the present invention is illustrated inFIGS. 28 and 29. Thevalve1310 comprises a body orhousing1312, a support member1314 (partially shown), anupper seal1316, and alower seal1318. Thehousing1312 has anupper conduit1322 near a proximal end with acircular opening1324 that is preferably adapted to receive a medical implement such as asyringe1326 partially shown in phantom inFIG. 40. Thebody1312 has anupper side wall1330 distal to theupper conduit1322 that is desirably circular in cross section with a diameter larger than the diameter of thecircular opening1324. Thebody1312 has alower side wall1332 distal to theupper side wall1330 with a diameter larger than the diameter of theupper side wall1330. Amiddle conduit1338 is advantageously formed between theupper side wall1330 andlower side wall1332. Theupper side wall1330 is advantageously tapered from theupper conduit1322 to themiddle conduit1338 and thelower side wall1332 is advantageously tapered from themiddle conduit1338 to adistal end1340 of thehousing1312. Themiddle conduit1338 has a diameter larger than the diameter of theupper conduit1322 and smaller than the diameter of thedistal end1340 of thehousing1312.
• Thesupport member1314 has at its distal end an inner conduit (not shown) which may be connected to a terminal of a catheter (not shown). Thesupport member1314 serves as a support and attachment device for the upper andlower seals1316,1318 by holding theseals1316,1318 in place inside theinternal cavity1346 of thehousing1312.
• The upper andlower seals1316,1318 are prepared from a resilient material that is flexible, inert, and impermeable to fluid, such as silicon. Theupper seal1316 has aseal cap1350 with a generally flattop surface1352, ashoulder1354, aside wall1356, and abase1358. Theside wall1356 advantageously is comprised of ringedwall portions1360 which deform in an accordion-like fashion and assist in the reformation of theseal1316 to enclose thehousing opening1324 upon withdrawal of thesyringe1326. During compression of theupper seal1316, the diameter of the ringedwall portions1360 expand outwardly in the radial direction. The interior of theupper seal1316 is hollow to provide an upperinner cavity1362, as best seen inFIG. 28. Theshoulder1354 engages anupper ledge1366 provided in theupper conduit1322 of thehousing1312 such that theupper ledge1366 confines the movement of theshoulder1354 toward theopening1324 to prevent theupper seal1316 from being blown through theopening1324 under high pressure in the upperinner cavity1362 of theseal1316,
• Theseal cap1350 of theupper seal1316 reseals in thevalve1310 at theopening1324 with thetop surface1352 of theseal1316 flush with or above theopening1324 upon removal of the medical implement1326. Theseal cap1350 substantially fills theopening1324 in the top of theupper conduit1322. It is preferred thetop surface1352 be exposed after assembly so that it may be swabbed with alcohol or other disinfectant. Theseal cap1350 of theupper seal1316 desirably has a unique shape with aprecut slit1370 such that theseal cap1350 is squeezed shut by theopening1324 when assembled and theslit1370 opens automatically during compression. Theseal1316 desirably also includes a pressureresponsive member1372 to further assist in creating a fluid-tight seal in the decompressed state.
• As shown inFIGS. 28 and 29, thelower seal1318 desirably is generally similar to theupper seal1316. The lower seal has asimilar seal cap1380 with a generally flattop surface1382, ashoulder1384, and aside wall1386. Theside wall1386 defines a lowerinner cavity1390 and may include similar ringed wall portions (not shown). Theseal cap1380 is disposed at themiddle conduit1338 at the decompressed state and reseals the lowerinner cavity1390 at themiddle conduit1338 upon removal of the medical implement1326. The lowerinner cavity1390 forms a fluid space of thevalve1310, being in fluid communication through the lower conduit (not shown) to, e.g., a catheter (not shown). The valve components are configured and dimensioned to assist in causing the fluid space to increase upon insertion of the medical implement1326 and to decrease upon withdrawal of the medical implement1326.
• Theseal cap1380 advantageously provides a fluid tight seal, having a shape and aprecut slit1394 similar to those of theupper seal1316. Thelower seal1318 also includes desirably a pressureresponsive member1396 similar to the pressureresponsive member1372 of theupper seal1316. The components of thelower seal1318 are generally larger than those of theupper seal1316 because of the geometry of thevalve housing1312.
• To illustrate valve activation,FIG. 29 shows the compressed state of thevalve1310 upon insertion of thesyringe1326. Thesyringe1326 is placed on theupper seal cap1350 inside theopening1324 of thehousing1212. The application of pressure on thesyringe1326 creates pressure on theseal cap1330, and the resulting downward pressure compresses theupper seal1316. This pushes theseal cap1350 away from thecircular opening1324 and toward themiddle conduit1338 at a region with a larger inner diameter, thereby allowing theprecut slit1370 to open. The downward movement is facilitated by the compression of the ringedwall portions1360 of theside wall1356 of theupper seal1316. The downward force is transferred to thelower seal1318 through thebase1358 of theupper seal1316 which cooperates with theseal cap1380 of thelower seal1318. The application of the pressure pushes thelower seal cap1380 away from themiddle conduit1338 and toward the lower portion of thehousing1312 which has a larger inner diameter, thereby allowing theprecut slit1394 to open. Fluid is now able to flow into thesyringe1326, or vice versa, depending on whether fluid is to be withdrawn from the patient or medication injected into the patient.FIG. 29 shows thevalve1310 opened by insertion of thesyringe1326 into theopening1324.
• In the compressed state shown inFIG. 29, the fluid space generally contract under pressure from the decompressed state shown inFIG. 28. Upon removal of thesyringe1326 from theupper conduit1322, as shown inFIG. 28, the upper andlower seals1316,1318 are free to move toward their decompressed states. The movement normally would cause a general expansion of the fluid space. However, because of the fluid communication between the upperinner cavity1362 and lowerinner cavity1390, and the closing of theprecut slit1394 of thelower seal1318 upon compression, a decrease in volume results in the lowerinner cavity1390 of thevalve1310. The decrease in the fluid space advantageously generates a positive flow from thevalve1310 through, e.g., a catheter tip (not shown) to eliminate dead space. Advantageously, any dead space within the upperinner cavity1362 is also minimized since, as thesyringe1326 is withdrawn, theslit1370 remains open until the very end, i.e., until theseal cap1350 is squeezed by thecircular opening1324 at the top of theupper conduit1322. The elimination of backflash is particularly advantageous in the case where thevalve1310 is connected through a catheter to a patient, because it prevents the introduction of blood into the catheter.
• As theupper seals1316 is free to move to its decompressed state, it essentially fills thecircular opening1324. The ability of theupper seal1316 to return reversibly to its decompressed state, together with the resiliency of thelower seal1318, permits the reuse of thevalve1310. Following disconnection, and before reuse, thesurface1352 of theseal cap1316 is essentially flush with theopening1324 of thehousing1312. Thus, thisflush surface1352 can advantageously be sterilized with alcohol or other surface decontaminating substances. A cover cap (not shown) can further be used to fit over the upper conduit to protect thesurface1352 of theseal cap1350.
Fourteenth Embodiment
• A fourteenth embodiment of avalve1410 of the present invention is illustrated inFIGS. 30 and 32, and comprises a valve body orhousing1412, aseal1414, apiston1416, and aspring1418. Thehousing1412 has anupper conduit1420 near a proximal end with acircular opening1422 that is preferably adapted to receive a medical implement such as asyringe1423 partially shown in phantom inFIG. 30. Thehousing1412 has aside conduit1424 which is connected to a fluid line such as a catheter (not shown). Disposed in alower chamber1426 of thehousing1412 is thespring1418 supporting thepiston1416 which bears against adistal end1430 of theseal1414 disposed in anupper chamber1432 of thehousing1412. Thelower chamber1426 of thehousing1412 advantageously includes anorifice1434 for venting the air therein to facilitate movement of thespring1418. Theupper chamber1432 andlower chamber1426 expand and contract according to the movement of thepiston1416 under pressure from theseal1414 and thespring1418. Thehousing1412 advantageously includes aside aperture1438 additional fluid to be transferred to the patient through theupper chamber1432 andside conduit1424 when necessary.
• Theseal1414 hasseal cap1442 withprecut slit1444, ashoulder1446, and a pressureresponsive member1448. The seal has aside wall1450 which defines aninner cavity1452 and has thedistal end1430 that cooperates with thepiston1416 for efficient transfer of pressure between them. Near thedistal end1430 of theseal1414 is desirably atransverse fluid passage1456 for fluid communication between theseal1414 and theupper chamber1432. AlthoughFIGS. 30 and 32 illustrate that thetransverse fluid passage1456 also facilitates fluid flow between theside aperture1438 and theside conduit1424, it need not do so if fluid can flow around theseal1414 in theupper chamber1432. Theupper chamber1432 and theinner cavity1450 of theseal1414 forms the fluid space of thevalve1410.
• FIG. 31 illustrates compression andFIG. 30 illustrated decompression during valve activation. In the compressed state, thesyringe1423 is placed on theseal cap1442 inside theopening1422 of thehousing1412 and the application of pressure on thesyringe1423 creates pressure on theseal cap1442. The downward pressure pushes theseal cap1442 away from thecircular opening1422 and toward the lower portion of thehousing1412 which has a larger inner diameter, thereby allowing theprecut slit1444 to open. Theside wall1450 moves further into theupper chamber1432 and pushes the piston1476 downward against thespring1418, which is compressed, storing potential energy of the compression. Fluid is able to flow into thesyringe1423, or vice versa, depending on whether fluid is to be withdrawn from the patient or medication injected into the patient. The compression of theseal1414 shown inFIG. 42 generates a net gain or increase in volume of the fluid space of thevalve1410.
• FIG. 30 illustrates thevalve1410 after withdrawal of thesyringe1423. Theseal1414 returns to its decompressed state and essentially fills theopening1422, and thepiston1416 moves back to its decompressed position as thespring1418 releases its potential energy. Because of the contraction of theupper chamber1432 of thehousing1412, there is a net loss in fluid space, resulting in a positive flow from thevalve1410 through, e.g., a catheter tip (not shown). The positive-flow valve1410 advantageously eliminates any dead space during decompression of theseal1414. This is further assisted by the seal141 with theslit1444 remaining open until the very end, i.e., until theseal cap1442 is squeezed by thecircular opening1422 at the top of theupper conduit1420.
• In addition, thevalve1410 can be reused because theseal1414 can return reversibly in the decompressed state. The seal surface1460 is also swabbable for sterility. Other features of thevalve1410 are discussed previously in connection with the earlier embodiments of this invention.
Additional Embodiments
• Additional embodiments of the present invention are contemplated without departing from the spirit and scope of the present invention. For instance, the volume inside a straight tubing contracts when the tube is bent. Thus, one valve embodiment valve may have a fluid space inside a straight tubing which bends upon insertion of a medical implement and reforms upon withdrawal of the medical implement, thereby effecting positive flow.
• In addition, many of the ringed side wall of the seals (such as theportions1360 of theseal1316 ofFIG. 28) can be replaced bycircular tires1580 stacked in series one on top of an adjacent larger-diameter lower tire, as illustrated inFIG. 32. Thecircular tires1580 are preferably solid throughout the diameter of the cross-section thereof. Like the ringedside wall portions1360, thesecircular tires1580 will deform and reform upon, respectively, compression and decompression of the seal.
CONCLUSION
• In the embodiments described above, the fluid space inside the valve increases upon insertion of a medical implement in the compressed state and decreases upon withdrawal of the medical implement in the decompressed state. In some embodiments, the structure defining the fluid space is substantially relaxed and does not store substantial amount of potential energy. Insertion of the medical implement causes a change in the structure that allows it to store potential energy. The potential energy is released upon withdrawal of the medical implement and the structure returns to a substantially relaxed condition. In other embodiments, at least some components of the structure defining the fluid space stores potential energy under strain or deformation. Upon insertion of a medical implement in the compressed state, the potential energy in those components is released and is stored in other components of the structure or in another form. The stored potential energy in the compressed state is released when the medical implement is removed, and the original potential energy is restored in the structure.
• The above presents a description of the best mode contemplated of carrying out the present invention, and of the manner and process of using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains to make and use this invention. This invention is, however, susceptible to modifications and alternate constructions from that discussed above which are fully equivalent. In particular, many of the features of the co-pending applications, serial nos. and can be incorporated into the present invention, and these applications are incorporated herein by reference. The embodiments described are meant to be illustrative and not exhaustive. Consequently, it is not the intention to limit this invention to the particular embodiments disclosed. On the contrary, the intention is to cover all modifications and alternate constructions coming within the spirit and scope of the invention as generally expressed by the following claims, which particularly point out and distinctly claim the subject matter of the invention.

Claims (1)

1. A medical valve for controlling the flow of fluid between a first medical implement and a second medical implement, said valve comprising:

a body having a cavity in fluid communication with a second medical implement and an opening adapted to receive a first medical implement;

a sealing element positioned within said body and movable between a first position in which said sealing element prevents fluid flow through said cavity and a second position in which fluid flow is permitted through said cavity, said cavity including a fluid space which automatically and reversibly increases in size when said first medical implement is connected to said valve and which contracts in size when said first medical implement is disconnected, said sealing element including a rigid piston movably mounted with respect to said body; and

a ledge positioned within said cavity, said sealing element having a shoulder engaging said ledge when said sealing element moves into said first position.

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