Patent Application
20100249725
The invention generally relates to medical valves and, more particularly, the invention relates to mitigating fluid drawback through medical valves.
In general terms, medical valving devices often act as a sealed port that may be repeatedly accessed to non-invasively inject fluid into (or withdraw fluid from) a patient's vasculature. Consequently, a medical valve permits the patient's vasculature to be freely accessed without requiring such patient's skin be repeatedly pierced by a needle.
Medical personnel insert a medical instrument into the medical valve to inject fluid into (or withdraw fluid from) a patient who has an appropriately secured medical valve. Once inserted, fluid may be freely injected into or withdrawn from the patient. Problems can arise, however, when the medical instrument is withdrawn from the valve. Specifically, suction produced by the withdrawing medical instrument can undesirably cause blood to be drawn proximally into or toward the valve. In addition to coagulating and impeding the mechanical operation of the valve, blood in the valve also compromises the sterility of the valve.
In accordance with one embodiment of the present invention, a medical valve transitions between an open mode that permits fluid flow, and a closed mode that prevents fluid flow. The medical valve may include a housing with an inlet and an outlet, a valve member within the housing, a first variable volume region and a second variable volume region. The valve member may have a distal seal member with a normally closed aperture passing through it. The distal seal may include a protrusion that extends distally from the distal seal and provides a dynamic back pressure seal. The normally closed aperture may pass through the protrusion and insertion of a medical implement into the inlet may open the aperture and fluidly connect the inlet and outlet via a fluid path between the inlet and outlet. Conversely, withdrawal of the medical implement may close the aperture and fluidly disconnect the inlet and outlet.
The first and second variable volume regions may be longitudinally spaced from one another and may be part of the fluid path. The first variable volume region may contract and the second variable volume may expand upon withdrawal of the medical implement. Conversely, the first variable volume may expand and the second variable volume may contract upon insertion of the medical instrument. The fluid path may have a closed volume before insertion of the medical implement and an open volume in the open mode. The closed volume may be substantially equal to the open volume. Additionally, the volumes of the first and second variable volume regions may be configured, respectively, to contract and expand to produce substantially neutral fluid displacement at the outlet during disconnection and/or connection of the medical implement.
The open volume of the fluid path may be the volume of the fluid path when the medical implement is inserted to its farthest point. Alternatively, the open volume of the fluid path may be the volume of the fluid path when the medical implement is only partially inserted, when the aperture first opens, or when the aperture is fully open.
In accordance with some embodiments, the distal seal member may bound the second variable volume region when the valve is in the closed mode, and the valve may include a post member that is moveably mounted within the housing. The post member may move distally within the housing to fluidly connect the inlet and outlet upon insertion of the medical implement into the inlet. The post member may move proximally within the housing to fluidly disconnect the inlet and outlet upon withdrawal of the medical implement. The post member may have a flow channel that fluidly communicates the first volume and the second volume when the valve is in the open mode. The flow channel may also allow fluid from the first volume to enter the second volume as the first volume contracts.
The post member may include a tube portion and a head portion (e.g., a post head) that protrudes radially outward from the tube portion. The head portion may include a proximally facing surface, a distally facing surface, and at least one post head channel extending between the proximally facing surface and the distally facing surface. Additionally, the first variable volume may have a first sub-volume and a second sub-volume that are separated by the head portion. For example, the first sub-volume may be proximal to the proximally facing surface and the second sub-volume may be distal to the distally facing surface. Upon withdrawal of the medical implement, the first sub-volume may contract and the second sub-volume may expand. The post head channel fluidly connects the first and second sub-volumes.
In accordance with further embodiments, the head portion may have a plurality of distally extending protrusions that apply a force on the distal seal to open the aperture (e.g., as the medical implement is inserted). Alternatively, the post member may include a tube portion and a plurality of legs extending distally from a distal end of the tube portion. The leg portions may apply a force on the distal seal to open the aperture as the medical implement is inserted into the inlet. For example, the plurality of legs may apply a radially directed force and a longitudinally directed force on the distal seal as the post member moves distally. The radially directed force and longitudinally directed force may open the aperture and deform the distal seal member.
In accordance with other embodiments, at least a portion of the distal seal member may invert from a first shape (e.g., concave) to a second shape (e.g., convex) as the aperture opens. Additionally, the valve may also include a proximal seal member with a normally closed aperture through it. In such embodiments, insertion of the medical implement moves the proximal seal member distally and opens the proximal seal aperture. The proximal seal member may be swabbable when the valve is in the closed mode. The first variable volume may be located between the post member and the distal seal and the second variable volume may be located between the post member and the proximal seal.
In accordance with some embodiments, the medical implement may travel a distal stroke distance to open the aperture and a proximal stroke distance to close the aperture. The distal stroke distance may be the distance from initial connection of the medical implement to the point at which the aperture first opens. The proximal stroke distance may be the distance from the point at which the medical implement is fully inserted to the point at which the aperture first closes. The proximal stroke distance may be less than the distal stroke distance (e.g., 25% of the distal stroke distance).
In accordance with additional embodiments of the present invention, a method connects a medical valve to a patient. Among other things, the medical valve may include a housing with an inlet and an outlet, a valve member with a distal seal member having a normally closed aperture, a first variable volume region, and a second variable volume region. The first variable volume region may be longitudinally spaced from the second variable volume region. The method then inserts a medical implement through the inlet and moves the medical implement distally within the housing. The distal movement of the medical implement transitions the valve from a closed mode to an open mode by opening the normally closed aperture and fluidly connecting the inlet and outlet via a fluid path between the inlet and the outlet. The first and second variable volumes may be part of the fluid path.
The method may then transfer fluid between the medical implement and the patient through the valve. After transferring fluid, the method may move the medical implement proximally within the housing to fluidly disconnect the inlet and outlet by closing the aperture. During withdrawal of the medical implement, the first variable volume region may contract and the second variable volume region may expand. The fluid path may have a closed volume before insertion of the medical implement and an open volume when in the open mode. The closed volume may be substantially equal to the open volume.
In accordance with further embodiments of the present invention, a medical valve transitions between an open mode that permits fluid flow, and a closed mode that prevents fluid flow. The medical valve may include a housing with an inlet and an outlet, a valve means in the housing, a first means for forming a first variable volume, and a second means for forming a second variable volume. The valve means may have a distal sealing means with a normally closed aperture. Insertion of a medical implement into the inlet may open the aperture and fluidly connect the inlet and outlet via a fluid path between the inlet and outlet. Withdrawal of the medical implement may close the aperture and fluidly disconnect the inlet and outlet.
The second variable volume region may be longitudinally spaced from the first variable volume region. The first variable volume region may contract and the second variable volume region may expand upon withdrawal of the medical implement. The fluid path may have a closed volume before insertion of the medical implement and an open volume when in the open mode. The closed volume may be substantially equal to the open volume.
In accordance with further embodiments, a medical valve has an open mode that permits fluid flow, and a closed mode that prevents fluid flow. The medical valve may also include a housing with an inlet and an outlet, a valve member within the housing, a first variable volume region, and a second variable volume region. The valve member may have a distal seal member with a normally closed aperture therethrough. Insertion of a medical implement into the inlet may open the aperture and fluidly connect the inlet and outlet via a fluid path between the inlet and the outlet. Withdrawal of the medical implement closes the aperture and fluidly disconnects the inlet and outlet.
The second variable volume region may be longitudinally spaced from the first variable volume region. The first and second variable volume regions may be part of the fluid path. The first variable volume region may contract upon withdrawal of the medical implement and the second variable volume region may expand upon withdrawal of the medical implement.
The fluid path may have a closed volume before insertion of the medical implement and an open volume when in the open mode. The closed volume may be less than the open volume. The volumes of the first and second variable volume regions may be configured to respectively contract and expand to produce a positive fluid displacement at the outlet during disconnection of the medical implement.
The foregoing features of the invention will be more readily understood by reference to the following detailed description, taken with reference to the accompanying drawings, in which:
In illustrative embodiments, a medical valve has an internal valve mechanism with a post member that is moveable to open an aperture in a resilient member. The medical valve may also have multiple variable volume regions and a quick close aperture so that the valve has a substantially neutral fluid displacement at the outlet upon connection and/or disconnection of a medical instrument. Details of illustrative embodiments are discussed below.
After the valve 10 is in place, a nurse, doctor, technician, practitioner, or other user (schematically identified by reference number 20) may intravenously deliver medication to the patient 30, who is lying in a hospital bed. To that end, before the valve 10 is properly primed and flushed (e.g., with a saline flush), the nurse 20 swabs the top surface of the valve 10 to remove contaminants. Next, the nurse 20, once again, swabs the top surface of the valve 10 and uses a medical instrument 40 (e.g., a syringe having a distally located blunt, luer tip complying with ANSI/ISO standards) to inject medication into the patient 30 through the valve 10. For example, the medical practitioner 20 may use the valve 10 to inject drugs such as heparin, antibiotic, pain medication, other intravenous medication, or other fluid deemed medically appropriate. Alternatively, the nurse 20 (or other user) may withdraw blood from the patient 30 through the valve 10.
The medical valve 10 may receive medication or other fluids from other means, such as through a gravity feed system 45. In general, traditional gravity feeding systems 45 often have a bag 50 (or bottle) containing a fluid (e.g., anesthesia medication) to be introduced into the patient 30. The bag 50 (or bottle) typically hangs from a pole 47 to allow for gravity feeding. The medical practitioner 20 then connects the bag/bottle 50 to the medical valve 10 using tubing 60 having an attached blunt tip. In illustrative embodiments, the blunt tip of the tubing has a luer taper that complies with the ANSI/ISO standard.
After the tubing 60 is connected to the medical valve 10, gravity (or a pump) causes the fluid to begin flowing into the patient 30. In some embodiments, the feeding system 45 may include additional shut-off valves on the tubing 60 (e.g., stop-cock valves or clamps) to stop fluid flow without having to disconnect the tubing 60 from the valve 10. Accordingly, the valve 10 can be used in long-term “indwell” procedures.
After administering or withdrawing fluid from the patient 30, the nurse 20 should appropriately swab and flush the valve 10 and catheter 70 to remove contaminants and ensure proper operation. As known by those skilled in the art, there is a generally accepted valve swabbing and flushing protocol that should mitigate the likelihood of infection. Among other things, as summarized above, this protocol requires proper flushing and swabbing before and after the valve 10 is used to deliver fluid to, or withdraw fluid from the patient 30.
In this context, fluid displacement generally refers to the flow of fluid through the distal port 120 of the valve 10 (discussed below). Accordingly, a positive fluid displacement generally refers to fluid flowing in a distal direction through the distal port 120, while a negative fluid displacement generally refers to a fluid flowing in a proximal direction through the distal port 120. Of course, not all embodiments exhibit this quality. For example, in alternative embodiments, the valve 10 may have a negative fluid displacement when the instrument 40 is withdrawn.
It should be noted that the fluid displacements discussed herein refer to the “net” fluid displaced through the distal port 120. Specifically, during insertion or withdrawal of the instrument 40, the actual flow of fluid through the distal port 120 may change direction and thus, fluctuate. However, when considering this fluctuation, the net change in fluid flow through the distal port 120 should be 1) positive when the valve exhibits a “positive fluid displacement,” and 2) negative when the valve exhibits a “negative fluid displacement.” In a similar manner, a substantially neutral fluid displacement occurs when, as noted above, the valve 10 has a net fluid displacement of between about plus or minus one microliter. Of course, the fluid displacement of the valve 10 is discussed herein in terms of one stroke of the instrument 40 (i.e., insertion or withdrawal of the instrument 40).
Ideally, a valve with a neutral displacement has 0.0 microliters of positive or negative fluid displacement. As suggested above, however, in practice, a neutral displacement actually can have a very slight positive or negative displacement (e.g., caused by a manufacturing tolerance), such as a displacement on the order of positive or negative one microliter, or less. In other words, in such embodiments, the volumes of fluid forced through the distal port 120 in a neutral displacement valve are negligible (ideally zero microliters) and should have a negligible impact on the goals of the valve.
Some embodiments may have a very low positive or negative fluid displacement upon withdrawal. For example, such valves may have a negative fluid displacement of about one to two microliters (i.e., about one to two microliters of fluid drawback, which is proximally directed), or about one to two microliters positive fluid displacement (i.e., about one to two microliters of positively pushed fluid, which is distally directed). Although such amounts are in the positive or negative fluid displacement ranges, they still should represent a significant improvement over valves that exhibit higher positive or negative fluid displacements upon withdrawal.
The neutral, positive, or negative fluid displacement of a valve may be corrupted by manual handling of the valve 10, catheter 70 or the instrument 40 during the fluid transfer. For example, a slight inward force applied to the shaft of the medical instrument 40 (e.g., by the nurse's hand when simply holding the medical instrument 40) can have the effect of adding a positive fluid displacement from the medical instrument 40 (when the force is applied) and, ultimately, through the valve 10. In fact, releasing this force from the medical instrument 40 actually may draw fluid proximally, causing a negative fluid displacement that further corrupts fluid displacement. These effects, however, should not be considered when determining the nature of fluid displacement through the distal port 120. To overcome the problem noted above with regard to squeezing the medical instrument shaft, for example, the nurse 20 can hold another part of the medical instrument that does not contain the fluid (e.g., stubs at the proximal end of the medical instrument 40).
To accomplish these desired goals, the valve 10 has a housing 100 forming an interior having a proximal port 110 for receiving the instrument 40, and the noted distal port 120 having the discussed fluid displacement properties. The valve 10 has an open mode that permits fluid flow through the valve 10, and a closed mode that prevents fluid flow through the valve 10. To that end, the interior contains a valve mechanism that selectively controls (i.e., allow/permits) fluid flow through the valve 10. The fluid passes through a complete fluid path that extends between the proximal port 110 and the distal port 120.
It should be noted that although much of the discussion herein refers to the proximal port 110 as an inlet, and the distal port 120 as an outlet, the proximal and distal ports 110 and 120 also may be respectively used as outlet and inlet ports. Discussion of these ports in either configuration therefore is for illustrative purposes only.
The valve 10 is considered to provide a low pressure seal at its proximal end 110. To that end, the proximal end 110 of the medical valve 10 has a resilient proximal seal 80 with a resealable aperture 130 that extends entirely through its profile. The aperture 130 may, for example, be a pierced hole or a slit. Alternatively, the proximal seal 80 may be molded with the aperture 130. To help center the proximal seal 80 within the proximal port 110 and keep the aperture 130 closed (e.g., by pre-loading the aperture 130), the proximal gland may have centering ribs 82 nearer the proximal end of the proximal seal 80.
As mentioned above, some embodiments of the present invention may be swabbable. To that end, the proximal seal 80 may be substantially flush with or extend slightly proximal to the proximal port 110 when the valve 10 is in the closed mode. This creates a swabbable surface at the inlet of the valve 10 and allows the nurse 20 to perform the swabbing protocol discussed above.
The internal valve mechanism may include a post member 330 that cooperates with a resilient member 340 to selectively open and close the valve 10. In the embodiment shown in
As shown in
As noted above, the post member 330 may also include the post head 360, located at the distal end 358 of the tubular portion 350 (e.g., distal to the transverse holes 354). As is shown in
The resilient member 340 may include a proximal gland 370 and a distal gland 390. As shown in
The proximal gland 370 may also include the above noted proximal seal 80 at the inlet/proximal port 110 of the valve 10. As discussed above, this proximal seal 80 may include an aperture 130 that extends through its profile to provide a low-pressure seal at the valve inlet. The proximal gland 370 may also include additional features that help facilitate valve opening and closing. For example, the proximal gland 370 may include a shelf portion 374 and a rib 376. As discussed in greater detail below, the shelf portion 374 interacts with the post member 330 as the valve 10 is transitioning between the open and closed modes.
The rib 376 may be, for example, a larger diameter section of the proximal gland 370 and may function as a reinforcement and/or as a positive stop. For example, during valve 10 actuation, the rib 376 may prevent the post member 330 from extending through the shelf portion 374 and into the proximal volume 380 (e.g., the reinforcement function). Additionally, the rib 376 may help prevent the valve mechanism (e.g., the resilient member 340 and post member 330) from being urged past the closed position when the valve 10 is exposed to high back-pressures (e.g., the positive stop function).
As also shown in
In addition to the proximal gland 370 described above and as noted above, the resilient member 340 may also include a distal gland 390 located within the outlet housing 170. The distal gland 390 has a radial flange 392 that is secured to the housing 100 (e.g., between the inlet housing 160 and the outlet housing 170) along with the radial flange 378 of the proximal gland 370. The distal gland 390 may also have a radial ledge 394 that extends from the radial flange 392 to a distal seal portion 396. When the valve 10 is in the closed mode, the post head 360 may rest on the top of the radial ledge 394.
As shown in
It is important to note that the tapered wall region 400 may have different configurations and/or profiles as long as the surface is generally increasing proximally or distally (e.g., as long as the top of the distal seal aperture 398 is located proximal to or distal to the inversion point 404) and permits the inversion discussed below. For example the wall may be stepped downward or stepped upward. Additionally or alternatively, the tapered wall region 400 may have an irregular profile, a frusto-conical shape, a hemispherical shape, cylindrical shape, or other undefined shape. It is also important to note that tapered wall region 400 does not have to be gradually increasing and/or decreasing or have a smooth surface. The tapered wall region 400 may have protrusions, groves, or other irregularities as long as, as a whole, the surface/wall is tapered (concave or convex, whichever the case may be).
In addition to the above, the distal gland 390 may also have additional features that aid in the transition between the open and closed modes. In some embodiments, these additional features may also help prevent back-pressure (e.g., a proximally directed pressure) from opening the distal seal aperture 398. For example, some embodiments may have one or more compression fingers 402 extending radially out from the distal gland member 390. To aid in back-pressure sealing, the compression fingers 402 may be configured such that one end of the finger 402 contacts an inner wall of the outlet housing 170. In such embodiments, the compression fingers 402 may apply a radially compressive force on the distal seal aperture 398 to pre-load the aperture 398 and increase the valve's back-pressure sealing capability. To that end, the compression fingers 402 may be slightly larger than the inner diameter of the outlet housing 170 so as to create an interference compression with the outlet housing 170.
To ensure that the compression fingers 402 are able to deform, invert, and return to their at-rest/closed position (e.g., as discussed in greater detail below), the distal gland 390 may also include stiffening gussets 408. As best shown in
As shown in
It is important to note that the post head 360 may split the distal volume 420 into two sub-volumes. The first sub-volume 422 may be located proximal to the post head 360 (e.g., between the top of the post head 360 and the bottom of the proximal gland 370) and the second sub-volume 424 may be located distal to the post head 360 (e.g., between the bottom of the post head 360 and the distal seal portion 396). When the valve 10 is in the closed mode, the first sub-volume 422 is substantially zero. However, as the post member 330 moves distally, the first sub-volume 422 increases, the second sub-volume 424 decreases, and the overall distal volume 420 increases (e.g., as the distal gland 390 deforms). Conversely, as the post member 330 moves proximally (e.g., during valve closing), the first sub-volume 422 decreases (e.g., back towards the substantially zero volume), the second sub-volume 424 increases, and the overall distal volume 420 decreases (e.g., as the distal gland 390 returns to the at-rest/closed position).
In order to allow fluid to pass back and forth between the first sub-volume 422 and the second sub-volume 424 (e.g., to allow for sub-volume expansion and contraction and to allow fluid to be transferred to/from the patient 30), the post head 360 is configured to allow fluid to pass through it. For example, the post head 360 may have holes 362 passing through it (e.g., as shown in
As mentioned above and illustrated in
Upon further distal movement of the medical instrument 40 into the valve 10, the bottom/distal portion of the shelf 374 (e.g., portion 342) will make contact with the post member 330 and begin to move the post member 330 distally within the housing 100. As mentioned above, the proximal end 356 of the tubular portion 350 may be configured to engage with the shelf 374. To that end (as shown in
Additionally, as the post member 330 moves distally, the post head protrusions 362 will begin to deform the distal gland 390. For example, as shown in
As also shown in
It should be noted that, in this context, the term “invert” or “inversion” refers to when components change position relative to other components. For example, the inversion of the tapered wall region 400 causes a relative change in position of the distal seal aperture 398 with respect to the inversion point 404. In particular, when in the non-inverted state, the top of the distal seal aperture 398 is distal to the inversion point 404. However, as the tapered wall region 400 inverts, the inversion point 404 moves distally such that, when in the inverted state, the top of the distal seal aperture 398 is proximal to the inversion point 404 (see
As mentioned above, the distal gland aperture 398 opens as the distal gland 390 deforms and the compression fingers 402 invert/deform downward. To aid in distal gland aperture 398 opening and distal gland 390 inversion, the outlet housing 170 may include an outlet protrusion 410, around the outlet, that extends proximally into the outlet housing 170. In such embodiments, the distal gland 390 may have a distally extending portion 406 that circumscribes the outlet protrusion 410. Therefore, as the valve 10 transitions from the closed mode to the open mode, the post member 330 deforms the distal gland 390 over the protrusion 410, which, in turn, aids in distal gland aperture 398 opening. For example, as the post member 330 applies the distally directed force on the tapered wall region 400 (e.g., radially outward from the outlet protrusion 410), the outlet protrusion 410 may act as a stop and/or a anchoring point about which the tapered wall region 400 may deform (e.g., to open the distal gland aperture 398).
Once the valve 10 is in the open mode (e.g., after the distal seal aperture 398 is open), the medical practitioner or other user may transfer fluid to and/or from the patient. When fluid is transferred to and/or from the patient 30, the fluid passes through a fluid path within the valve 10. As the name suggests, the fluid path is the path the fluid takes as it passes through the valve 10. As shown in
Upon disconnection and withdrawal of the medical implement 40, the resilient characteristics of the proximal gland 370 and the distal gland 390 urge the valve 10 from the open mode shown in
It is important to note that the configuration of the distal gland 390 and the manner in which it deforms helps the distal gland aperture 398 close very early in the return stroke of the medical implement 40. Specifically, minimal proximal movement of the post member 330 causes the tapered wall region 400 and the compression fingers 402 to return to their non-inverted states. This early inversion causes the distal gland aperture 398 to close. The amount of longitudinal movement of the medical implement 40 required to close the distal gland aperture 398, thus, preferably is much less than that required to open the distal gland aperture 398.
For example, in some embodiments, the total stroke distance of the medical implement 40 (e.g., as it is being inserted and/or withdrawn) may be approximately 0.25 inches. As the valve 10 transitions from the closed mode to the open mode, the distal seal aperture 398 may not open until the medical implement 40 has been inserted 0.20 inches or 80% of the total stroke distance. Conversely, as the valve transitions from the open mode to the closed mode, the distal seal aperture 398 may close within the first 0.05 inches of travel (or the within the first 20% of the total stroke distance). In other words, the travel distance required to close the distal seal aperture 398 may be only 25% of the distance required to open the distal seal aperture 398 (e.g., 0.05 inches is approximately 25% of 0.20 inches).
It is important to note that the above distances and percentages are merely examples and the total stroke distance, the distance required to open the distal seal aperture 398, and the distance required to close the distal seal aperture 398 may be higher or lower. For example, the total stroke distance may be greater or less than 0.25 inches (e.g., it may range from 0.22 inches to 0.27 inches). Additionally or alternatively, the distance required to open the distal seal aperture 398 may be greater than or less than the 0.2 inches (80% of the total travel distance) mentioned above. Similarly, the distance required to close the distal seal aperture 398 may be greater than or less than the 0.05 inches (20% of the total travel distance) mentioned above. For example, the distance required to open the aperture 398 may range from 60% to 90% of the total stroke distance and the distance required to close the aperture 398 may be 10% to 40% of the total stroke distance. The range to close the distal seal aperture 398 may also be 20% to 30%, 10% to 30%, 10% to 20%, 5% to 10% or less than 10% of the total stroke distance.
The “quick-close” nature of the distal gland aperture 398 helps reduce the amount of drawback upon disconnection. In particular, once the distal gland aperture 398 is closed, further proximal movement of the post member 330 or changes in the pressure and/or fluid volume proximal to the distal gland aperture 398 should not impact fluid movement/flow at the outlet. In other words, even if the volume increases or a pressure builds up proximal to the distal seal aperture 398 after it closes, the displacement at the outlet will not be impacted.
Although
As mentioned above, some embodiments of the present invention may exhibit a neutral fluid displacement upon connection and/or disconnection of the medical implement 40 (e.g., upon opening and closing of the valve 10). In addition to the quick-close nature of the distal gland aperture 398, the multiple variable volume regions (e.g., proximal volume 380 and distal volume 420) discussed above may also help achieve neutral fluid displacement. For example, as discussed above, the proximal volume 380 decreases and the distal volume 420 increases (e.g., as the distal gland 390 expands radially outward and downward as it deforms) as the valve 10 transitions from the closed mode to the open mode. Conversely, the proximal volume 380 increases and the distal volume 420 decreases as the valve 10 transitions from the open mode to the closed mode.
To that end, the fluid contained within the valve 10 may move toward and/or between the proximal volume 380 and distal volume 420 as one volume expands and the other contracts. For example, as the valve 10 is transitioning from the open mode to the closed mode, some of the fluid within the contracting distal volume 420 may flow toward the transverse hole(s) 354, through the post member fluid path 352, and into the proximal volume 380 as the proximal volume 380 expands. Similarly, as the valve 10 opens, the fluid contained within the proximal volume 380 may be expelled from the proximal volume 380 as it contracts. The expelled fluid may then flow into and/or toward the distal volume 420 as it expands (e.g., by entering the post member fluid path 352 and exiting through the transverse hole(s) 354).
In some embodiments, the changes in volume of both the proximal volume 380 and the distal volume 420 may be substantially equal. In other words, as the valve 10 opens, the distal volume 420 will increase by substantially the same amount that the proximal volume 380 decreases. Similarly, when the valve 10 closes, the proximal volume will increase by substantially the same amount that the distal volume 420 decreases. In such embodiments, the total fluid volume within the valve 10 will remain substantially constant as the valve transitions between the open and closed modes, thereby creating a substantially neutral fluid displacement at the outlet during both opening and closing of the valve 10.
In other embodiments, the proximal volume 380 and the distal volume 420 offset one another primarily when the valve 10 is in the open mode and up until the time that the distal seal aperture 398 closes. In such embodiments, once the distal seal aperture 398 closes (as noted above), any volume changes will not impact the fluid displacement at the outlet 120. Therefore, if the proximal volume 380 expands more or at a faster rate than the distal volume 420 contracts (e.g., increasing the total volume), there will be no drawback into the outlet 120. Similarly, if the proximal volume expands less or slower than the distal volume 420 contracts, there will be no positive displacement at the outlet 120.
It is important to note that, although the resilient member 340 is described above as having two pieces (e.g., the proximal gland 370 and the distal gland 390), the resilient member 340 may be manufactured as a single piece. For example, as shown in
In some embodiments, the proximal gland 370 and the distal gland 390 may become cross-linked. For example, during gamma sterilization, the proximal face 520 of the distal gland 390 and the distal face 530 of the proximal gland 370 may become cross-linked such that the two component essentially form a single piece. Additionally or alternatively, the components may be joined together in other ways including, but not limited to, using adhesives or plasma discharge treatments.
After connecting the valve 10 to the patient 30, the medical practitioner 20 swabs the valve proximal port 110 and inserts the medical instrument 40 into the proximal port 110 (step 820). As the medical practitioner 20 moves the medical instrument distally (step 830) into the medical valve 10, the instrument 40 will begin to deform the proximal seal 80 and move it distally to open the proximal aperture 130, as discussed above. As the proximal seal 80 deforms, the proximal volume 380 will collapse/contract and the shelf portion 374 will contact the post member 330 and begin to move the post member 330 distally to unseal the transverse hole(s) 354. Further insertion of the instrument continues to move the post member 330 distally and deforms/inverts the distal gland 390 and opens the distal seal aperture 398, as discussed above. When the distal seal aperture 398 opens, there is fluid communication between the proximal port 110 and the distal port 120. At this point, the valve 10 is open. The instrument may, in some instances, be inserted further even after the aperture 398 opens. In that case, the valve 10, should still function as described.
After opening the valve 10, the medical practitioner 20 can transfer fluids to or from the patient (step 840). For example, if the medical practitioner 20 wishes to administer a medication to the patient 30, he/she may depress the medical instrument plunger 40 (e.g., for a syringe) and transfer the medication into the patient 30. Alternatively, the medical practitioner 20 may withdraw blood from the patient 30.
After completing the fluid transfer(s), the medical practitioner 20 can remove the medical instrument (step 850). As discussed above, the medical practitioner 20 should take care not to squeeze the sides of the medical instrument 40. Doing so may create a false positive or negative displacement at the distal port 120 of the medical valve 10. If done properly, removal of the medical instrument 40 may result in a substantially neutral or a positive displacement at the valve distal port 120.
As discussed above with reference to
The fluid path through the valve 10 has a closed mode volume when the valve is in the closed mode and an open mode volume. The open mode volume may be the volume at any point after the distal seal aperture 398 opens. For example, the open mode volume may be the volume of the fluid path just after the distal seal aperture 398 opens. Alternatively, the open mode volume may be the volume at which the medical implement 40 can no longer be inserted into the valve 10 (e.g., when the medical implement is fully inserted). The open mode volume may also be the volume at any point between immediately after the distal seal aperture 398 opens and maximum insertion of the medical implement 40.
It is important to note that, even after the distal seal aperture 398 is open, further insertion of the medical implement 40 may continue to move the post member 330. This additional distal movement of the post member 330 may further deform the proximal gland 370 and the distal gland 390 which, in turn, may also change the volumes (e.g., proximal volume 380 and distal volume 420) within the valve 10. However, for the purposes of achieving the neutral displacement discussed above, the open mode volume of the fluid path need only be substantially equal to the closed mode volume at a single point after the distal seal aperture 398 opens (e.g., immediately after opening or when the medical implement 40 is fully inserted.
Thus, in various embodiments, between the open state and the quick-closed state (e.g., the state at which the distal seal aperture 398 first closes), the volume within the fluid path remains substantially constant to produce a neutral drawback. In other embodiments, the volume within the fluid path may increase to create a negative displacement (e.g., s drawback) or decrease to create a positive displacement at the outlet 120.
It should be noted that, although the above described embodiments contain a post member 330 with a post head 360, other embodiments may utilize different post member 330 configurations. For example, as shown in
As shown in
It is important to note that, although the legs 910 are described above as contacting the ledge 394, the legs 910 (and/or the post head protrusions 362) may contact other areas of the distal gland 390. For example, in some embodiments, the legs 910 may be angled such that they contact the tapered wall region 400 (e.g., as opposed to the ledge 394).
Various embodiments of the present invention may also include features that help keep the distal seal aperture 398 closed in the presence of a back-pressure or proximally directed force/pressure. For example, the distal seal 390 may include a thickened portion or a protrusion 399 extending distally into the outlet (see
Although the above discussion discloses various exemplary embodiments of the invention, it should be apparent that those skilled in the art can make various modifications that will achieve some of the advantages of the invention without departing from the true scope of the invention.
This patent application claims priority from U.S. Provisional Patent Application No. 61/164,585, filed Mar. 30, 2009, entitled, “Medical Valve with Distal Seal Actuator,” and naming Andy L. Cote and Jake Ganem as inventors, the disclosure of which is incorporated herein, in its entirety, by reference. This patent application is related to the following co-pending U.S. patent application: U.S. patent application Ser. No. ______, entitled, “MEDICAL VALVE WITH DISTAL SEAL ACTUATOR,” naming Andrew L. Cote and Jake P. Ganem as inventors, filed on even date herewith, and assigned attorney docket number 1600/A08, the disclosure of which is incorporated herein, in its entirety, by reference.
| Number | Date | Country | |
|---|---|---|---|
| 61164585 | Mar 2009 | US |
