U.S. patent application number 11/417773 was filed with the patent office on 2006-09-07 for positive flow valve.
Invention is credited to David C. Arnold, Alison D. Brummett, Dennis M. Bui, Thomas F. JR. Fangrow, Thomas J. Gustus, Bruce M. Hubrecht, George A. Lopez.
Application Number | 20060200089 11/417773 |
Document ID | / |
Family ID | 25079940 |
Filed Date | 2006-09-07 |
United States Patent
Application |
20060200089 |
Kind Code |
A1 |
Lopez; George A. ; et
al. |
September 7, 2006 |
Positive flow valve
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.
Inventors: |
Lopez; George A.; (Laguna
Beach, CA) ; Fangrow; Thomas F. JR.; (Mission Viejo,
CA) ; Arnold; David C.; (Mission Viejo, CA) ;
Hubrecht; Bruce M.; (Canyon Lake, CA) ; Brummett;
Alison D.; (Corona Del Mar, CA) ; Gustus; Thomas
J.; (Costa Mesa, CA) ; Bui; Dennis M.; (Alta
Loma, CA) |
Correspondence
Address: |
KNOBBE MARTENS OLSON & BEAR LLP
2040 MAIN STREET
FOURTEENTH FLOOR
IRVINE
CA
92614
US
|
Family ID: |
25079940 |
Appl. No.: |
11/417773 |
Filed: |
May 3, 2006 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
11085808 |
Mar 21, 2005 |
|
|
|
11417773 |
May 3, 2006 |
|
|
|
10163719 |
Jun 5, 2002 |
6932795 |
|
|
11085808 |
Mar 21, 2005 |
|
|
|
09411988 |
Oct 4, 1999 |
6428520 |
|
|
10163719 |
Jun 5, 2002 |
|
|
|
08767587 |
Dec 16, 1996 |
|
|
|
09411988 |
Oct 4, 1999 |
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Current U.S.
Class: |
604/246 |
Current CPC
Class: |
A61M 39/26 20130101;
A61M 39/045 20130101; A61M 2039/267 20130101; A61M 2039/263
20130101; A61M 2039/0072 20130101; A61M 2039/266 20130101 |
Class at
Publication: |
604/246 |
International
Class: |
A61M 5/00 20060101
A61M005/00 |
Claims
1. A medical connector for controlling a flow of fluid between
first and second medical implements, the medical connector
comprising: a housing comprising a first end, a second end, and an
interior cavity, the first end including a first opening adapted to
snugly receive an ANSI-standard luer of the first medical
implement, and the interior cavity comprising a region near the
first end with a first cross-sectional area smaller than a second
cross-sectional area in a region closer to the second end of the
housing than the first cross-sectional area, the second end of the
housing including an external conduit with a second opening and a
skirt portion with an internal screw thread adapted to be removably
connected to the second medical implement, and the exterior surface
of the housing having a first portion near the first end defining a
first external cross-sectional width and a second portion in the
distal direction from the first portion defining a second external
cross-sectional width larger than the first external
cross-sectional width wherein the second portion is in the proximal
direction from the skirt portion of the second end; a region on the
housing near the first end including an exterior surface with a
mounting structure adapted to be rotatably attached to a screw
thread on an internal surface of the first medical implement, the
exterior surface of the housing also including a shoulder portion
wider in diameter than the mounting structure, the shoulder portion
configured to halt the advancement of the first medical implement
along the mounting structure; a flexible member comprising a first
opening in the region of the first end of the housing and a second
opening in the region of the second end of the housing, and a fluid
passageway within the flexible member; and an interior conduit
having a fluid passageway and positioned within the interior
cavity, the conduit in fluid communication with the fluid
passageway of the flexible member, and a portion of the flexible
member overlapping the interior conduit; wherein the flexible
member is configured to move from a substantially closed position
to a substantially open position upon insertion of the luer of the
first medical implement into the first opening of the housing, the
flexible member overlaps the interior conduit to a greater extent
in the substantially open position than in the substantially closed
position, and the flexible member is configured to move from the
substantially open position to the substantially closed position
upon withdrawal of the luer of the first medical implement from the
first opening of the housing, the volume of the fluid passageway
within the flexible member being larger in the substantially open
position than in the substantially closed position so that fluid
contained within the flexible member upon the withdrawal of the
luer of the first medical implement is forced toward the second end
of the housing, the fluid passageway of the flexible member and the
interior conduit cooperating to form a substantially non-tortuous
fluid passageway through the valve when the flexible member is in
the substantially open position.
2. The medical connector of claim 1, wherein an end of the flexible
member closest to the first end of the housing is displaced in the
direction of the second end of the housing as the flexible member
moves from the substantially closed position to the substantially
open position.
3. The medical connector of claim 1, wherein the shape of the
flexible member urges the fluid passageway more tightly closed near
the first end of the housing when the passageway is under fluid
pressure.
4. The medical connector of claim 1, wherein an external surface on
the flexible member in the substantially closed position contacts
an internal surface of the interior cavity of the housing in a
region near the first end of the housing.
5. The medical connector of claim 4, wherein a portion of an
interior surface of the housing between the first end and the
second end is tapered.
6. The medical connector of claim 5, wherein the fluid passageway
is wider when the flexible member is in its substantially open
position than in its substantially closed position.
7. The medical connector of claim 6, wherein a first external
surface of the housing near the first end has a first
cross-sectional area, a second external surface of the housing
closer to the second end than the first external surface has a
second cross-sectional area, and the first cross-sectional area is
smaller than the second cross-section area.
Description
BACKGROUND OF THE INVENTION
[0001] This application is a continuation of pending U.S.
application Ser. No. 11/085,808, filed Mar. 21, 2005, which in 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, all of which are incorporated by
reference in their entirety.
FIELD OF THE INVENTION
[0002] 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.
DESCRIPTION OF THE RELATED ART
[0003] 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.
[0004] 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.
[0005] 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 a catheter 50 having a small
portion near the tip 52 that is inserted into the patient, and a
valve 54 connected between one end of the catheter and a medical
implement 56. 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 the medical implement 56 is withdrawn from the valve 54,
the space previously occupied by the implement 56 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.
[0006] 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.
[0007] One way to induce a positive flow in the catheter is
illustrated in FIGS. 2a and 2b. Here, the proximal end of a valve
180 is enclosed with a stylet or displacer 182 upon withdrawal of
the medical implement (not shown). An elongated portion 184 of the
stylet 182 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. The elongated portion 184, 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 the stylet 182 further
requires an additional step that may be overlooked by the nurse and
the stylet 182 may be misplaced or lost. In addition, this specific
type of valve 180 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
[0008] 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.
[0009] 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.
[0010] 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.
[0011] 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.
[0012] 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.
[0013] 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
[0014] 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:
[0015] FIG. 1 is a schematic cross-sectional view of a valve
forming a fluid connection between a syringe and a catheter.
[0016] FIGS. 2a and 2b illustrate a prior art valve which includes
a stylet having an elongated portion after use to induce a positive
flow.
[0017] 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.
[0018] FIG. 4 is a longitudinal cross-sectional view of the first
embodiment of the positive-flow valve of this invention before
compressing the seal.
[0019] FIG. 5 is a longitudinal cross-sectional view similar to
FIG. 4 showing the valve during compression of the seal.
[0020] FIG. 6 is a longitudinal cross-sectional view of the second
embodiment of the positive-flow valve of this invention before
compressing the seal.
[0021] FIG. 7 is a longitudinal cross-sectional view similar to
FIG. 6 showing the valve during compression of the seal.
[0022] FIG. 8 is a longitudinal cross-sectional view of the third
embodiment of the positive-flow valve of this invention before
compressing the seal.
[0023] FIG. 9 is a longitudinal cross-sectional view similar to
FIG. 8 showing the valve during compression of the seal.
[0024] FIG. 10 is a longitudinal cross-sectional view of the fourth
embodiment of the positive-flow valve of this invention before
compressing the seal.
[0025] FIG. 11 is a longitudinal cross-sectional view similar to
FIG. 10 showing the valve during compression of the seal.
[0026] FIG. 12 is a longitudinal cross-sectional view of the fifth
embodiment of the positive-flow valve of this invention before
compressing the seal.
[0027] FIG. 13 is a longitudinal cross-sectional view similar to
FIG. 12 showing the valve during compression of the seal.
[0028] FIG. 14 is a longitudinal cross-sectional view of the sixth
embodiment of the positive-flow valve of this invention before
compressing the seal.
[0029] FIG. 15 is a longitudinal cross-sectional view similar to
FIG. 14 showing the valve during compression of the seal.
[0030] FIG. 16 is a longitudinal cross-sectional view of the
seventh embodiment of the positive-flow valve of this invention
before compressing the seal.
[0031] FIG. 17 is a longitudinal cross-sectional view similar to
FIG. 16 showing the valve during compression of the seal.
[0032] FIG. 18 is a longitudinal cross-sectional view of the eighth
embodiment of the positive-flow valve of this invention before
compressing the seal.
[0033] FIG. 19 is a longitudinal cross-sectional view similar to
FIG. 18 showing the valve during compression of the seal.
[0034] FIG. 20 is a longitudinal cross-sectional view of the ninth
embodiment of the positive-flow valve of this invention before
compressing the seal.
[0035] FIG. 21 is a longitudinal cross-sectional view similar to
FIG. 20 showing the valve during compression of the seal.
[0036] FIG. 22 is a longitudinal cross-sectional view of the tenth
embodiment of the positive-flow valve of this invention before
compressing the seal.
[0037] FIG. 23 is a longitudinal cross-sectional view similar to
FIG. 22 showing the valve during compression of the seal.
[0038] FIG. 24 is a longitudinal cross-sectional view of the
eleventh embodiment of the positive-flow valve of this invention
before compressing the seal.
[0039] FIG. 25 is a longitudinal cross-sectional view similar to
FIG. 24 showing the valve during compression of the seal.
[0040] FIG. 26 is a longitudinal cross-sectional view of the
twelfth embodiment of the positive-flow valve of this invention
before compressing the seal.
[0041] FIG. 27 is a longitudinal cross-sectional view similar to
FIG. 26 showing the valve during compression of the seal.
[0042] FIG. 28 is a longitudinal cross-sectional view of the
thirteenth embodiment of the positive-flow valve of this invention
before compressing the seal.
[0043] FIG. 29 is a longitudinal cross-sectional view similar to
FIG. 28 showing the valve during compression of the seal.
[0044] FIG. 30 is a longitudinal cross-sectional view of the
fourteenth embodiment of the positive-flow valve of this invention
before compressing the seal.
[0045] FIG. 31 is a longitudinal cross-sectional view similar to
FIG. 30 showing the valve during compression of the seal.
[0046] 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
[0047] 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 a medical valve 190 to create a positive flow upon
disconnection of a medical implement (not shown) is illustrated in
FIG. 3. The roller-clamp valve 190 is activated manually by sliding
an external switch 192 to push a roller 194 against tubing 196
which connects a medical implement 198 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 the
tubing 196 can be opened by sliding the switch 192 in the reverse
direction.
[0048] This valve 190, however, has the same disadvantage of
requiring an additional step of operation as does the valve with a
stylet illustrated in FIGS. 2a and 2b, and also does not include a
seal having a swabbable surface. Furthermore, the size of the
roller 194 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
[0049] FIGS. 4 and 5 illustrate a first embodiment of a valve 210
in accordance with the present invention. In general, this valve
210 includes a valve body or housing 212, a support member 214, a
seal 216 defining an inner cavity 218, a pair of clam shells 220a
and 220b, and a spring 222. These components are assembled, as
depicted in FIG. 4, without the need for a spike element. The inner
cavity 218 forms an expandable fluid space inside the valve 210. As
discussed below, the clam shells 220a/220b are 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.
[0050] The body or housing 212 has an upper conduit 226 near a
proximal end 228, desirably with a circular opening 230 that is
adapted to receive the medical implement. A side wall portion 232
is preferably tapered to cooperate with the clam shells 220a/220b.
The body 212 has an upper ledge 234 formed between the proximal end
228 and the side wall portion 232. There is desirably a threaded
portion on the housing 212 adjacent the circular opening 230 in the
top of the upper conduit 226, as best seen in FIG. 4. Note that
"proximal" is used to denote the end of the valve 210 and other
components at or near the body opening 230, while "distal" is used
to denote the opposite end of the valve.
[0051] In the first embodiment, the upper conduit 226 is adapted to
receive the tip or nose 236 of an ANSI standard syringe 238, as
shown in phantom in FIG. 5. It is, however, contemplated that the
outer diameter of the upper conduit 226 can be of any size to
accommodate the attachment of other connector devices thereto.
Advantageously, the proximal end of the upper conduit 226 can be
equipped with a locking mechanism to facilitate locking of the
valve 210 to a variety of connector devices. For example, referring
to FIG. 4, the threaded portion of the housing 212 are preferably
provided such that the housing 212 can be locked into any
compatible Luer-Lock device known to those with skill in the art.
The housing 212 of the first embodiment according to this invention
includes conventional Luer-Lock threads 240 on the outer diameter
of the upper conduit 226.
[0052] The support member 214 has at its distal end the inner
conduit 242 which may be connected to a terminal end of a catheter
(not shown). The support member 214 serves as a support and
attachment device for the seal 216 by holding the seal 216 in place
inside the internal cavity 244 of the housing 212. The inner
conduit 242 and inner cavity 218 of the seal 216 present a
continuous passageway for fluid during use.
[0053] The seal 216 is prepared from a resilient material that is
flexible, inert, and impermeable to fluid, such as silicon. The
seal 216 has a seal cap 248 with a generally flat top surface 250,
a shoulder 252, a side wall 254, and a base 256. The side wall 254
advantageously is comprised of wall portions 258 which deform in an
accordion-like fashion and assist in the reformation of the seal
216 to close the housing opening 230 upon withdrawal of the syringe
238. During compression of the seal 216, the wall portions 258
expand outwardly in the radial direction. The interior of the seal
216 is hollow to provide the inner cavity 218, as best seen in FIG.
4. There are preferably gaps between the wall portions 258 which
facilitate deformation and reformation of the seal 216. The
shoulder 252 engages the upper ledge 234 provided in the upper
conduit 226 of the housing 212 such that the upper ledge 234
confines the movement of the shoulder 252 toward the opening 230 to
prevent the seal 216 from being blown through the opening 230 under
high pressure in the inner cavity 218 of the seal 216.
[0054] The seal cap 248 reseals the valve 210 at the opening 230,
with the top surface 250 of the seal 216 approximately flush with
or slightly above or below the opening 230 upon removal of the
medical implement 238. Preferably, the seal cap 248 substantially
fills the opening 230 in the top of the upper conduit 226. After
assembly, the top surface 250 of the seal cap 248 is essentially
flush with the opening 230, so that the seal cap 248 can be swabbed
with alcohol or other disinfectant without leakage of the
disinfectant into the valve 210. Therefore, it is preferable that
the top surface 250 be exposed so that it may be swabbed with a
disinfectant.
[0055] To provide a fluid-tight seal at the opening 230 and to
eliminate the need for a spike element to induce fluid flow upon
insertion of a medical implement, the seal cap 248 has a unique
shape and includes a precut slit 259, also having a unique shape.
The seal cap 248 desirably has an oval or elliptical shape with a
major axis having a length larger than the inner diameter of the
circular opening 230 such that the oval seal cap 248 substantially
fills the opening 230 in the top of the upper conduit 226 in the
decompressed state. The precut slit 259 in the seal cap 248 is
squeezed shut by the circular opening 230 in the decompressed
state, as seen in FIG. 4. In its resting state, the precut slit 259
is open. During compression of the seal 216 by insertion of a
medical implement such as the syringe 238, as illustrated in FIG.
5, the precut slit 259 returns to its resting state and opens, as
the seal cap 248 is allowed to stretch in the portion of the upper
conduit 226 which has a larger inner diameter. Fluid is thus
allowed to pass through the slit 259. Note that the terms
"compressed state" and "decompressed state" are used conveniently
to refer to compression and decompression of the seal 216 by
insertion and withdrawal of the medical implement 238 along the
longitudinal axis of the seal 216. The terms do not relate to the
radial compression of the seal cap 248 by the opening 230 of the
housing 212.
[0056] To further assist in creating a fluid-tight seal in the
decompressed state, the seal 216 of FIG. 4 advantageously includes
the enlarged, internal, pressure responsive member 260 which is
integral with the seal cap 248. The pressure responsive member 260
enables the valve 210 to maintain a fluid-tight seal even at very
high pressures sometimes experienced in medical applications,
particularly when the valve 210 is connected to a patient's
artery.
[0057] As shown in FIGS. 4 and 5, the clam shells 220a/220b are
desirably identical pieces disposed opposite one another
symmetrically inside the valve body 212. They are preferably made
of a firm material such as a hard plastic. The external surface
264a/264b of each clam shell 220a/220b is tapered to cooperate with
the tapered side wall portion 232 of the housing 212, and is
configured to slide along the side wall portion 232 during
compression and decompression. The internal surfaces 266a/266b of
the clam shells 220a/220b cooperate with one another to squeeze a
portion of the seal side wall 254, preferably adjacent the shoulder
252, to form a constricted portion 267 of the seal 216. The
proximal ends 268a/268b of the clam shells 220a/220b engage the
shoulder 252 of the seal 216 to facilitate movement of the clam
shells 220a/220b with the compression of the seal 216. The internal
surfaces 266a/266b preferably are shaped to cause the constricted
portion 267 to be substantially circular. In this embodiment, each
internal surface 266a/266b has a semi-circular, longitudinal groove
that squeezes the seal 216.
[0058] The spring 222 is disposed between the distal ends of the
clam shells 220a/220b and the base 256 of the seal 216, but
desirably a hard retaining disk 270 is provided adjacent the base
256 of the seal 216 to provide better support for the spring 222
and the seal 216. In the decompressed state shown in FIG. 4, the
spring 222 may be relaxed or be in slight compression to exert a
force on the seal 216 through the clam shells 220a/220b to keep the
seal 216 closed. During insertion of the syringe 238, the spring
222 is compressed and stores potential energy from the compression,
as illustrated in FIG. 5. Upon withdrawal of the syringe 238, the
spring 222 releases the potential energy and pushes the clam shells
220a/220b proximally to close the seal 216, as shown in FIG. 4. The
spring 222 is preferably not attached or bonded to either the clam
shells 220a/220b or the retaining disk 270 for ease of assembly.
Although FIGS. 4-5 show a helical spring 222, any suitable spring
known to those of skill in the art may be used.
[0059] The seal 216 is desirably relaxed longitudinally in the
decompressed state (FIG. 4), and compressed longitudinally in the
compressed state (FIG. 5). Alternatively, the seal 216 may be
stretched longitudinally in tension by the spring 222 in the
decompressed state and be relaxed or slightly compressed
longitudinal in the compressed state. The base 256 of the seal 216
advantageously fits snugly and securely into a annular groove 274
provided in the retaining disk 270 and an annular groove 276
provided in the support member 214. The annular grooves 274,276
form a locking mechanism to support and secure the seal 216 within
the cavity 244 of the housing 212.
[0060] To illustrate valve activation, FIG. 5 shows the compressed
state of the valve 210 upon insertion of the syringe 238. A medical
implement other than a syringe as known to those of skill in the
art may be used. The nose 236 of the syringe 238 is placed on the
seal cap 248 inside the opening 230 of the housing 212. The
application of pressure on the syringe 238 creates pressure on the
seal cap 248, and the resulting downward pressure compresses the
seal 216. This pushes the seal cap 248 away from the circular
opening 230 and toward the lower portion of the housing cavity 244
which has a larger inner diameter, thereby allowing the precut slit
259 to open. The downward movement is facilitated by the
compression of the spring 222 which stores the potential energy of
compression and by the gaps between the wall portions 258 of the
side wall 254 of the seal 216. Fluid is now able to flow into the
syringe 238, or vice versa, depending on whether fluid is to be
withdrawn from the patient or medication injected into the patient.
FIG. 5 shows the valve 210 opened by insertion of the nose 236 of
the syringe 238 into the opening 230. For intravenous applications,
the valve 210 can be oriented in the position diagramed in FIGS. 4
and 5, or it can be rotated 180' such that fluid flows in the
opposite direction.
[0061] In the compressed state shown in FIG. 5, the inner cavity
218 of the seal 216 generally contracts (becomes shorter) as
compared to the decompressed state shown in FIG. 4. The constricted
portion 267 of the inner cavity 218, defined by the clam shells
220a/220b, however, expands (becomes larger) in volume when the
seal 216 is in the compressed state. This results from a movement
of the clam shells 220a/220b apart from one another as they slide
along the tapered side wall 232 of the housing 212. The amount of
general contraction of the seal 216 in relation to the amount of
expansion of the constricted portion 267 during compression
determine whether the valve 210 generates a positive, negative, or
zero flow upon decompression, as discussed below.
[0062] Upon removal of the syringe 238 from the upper conduit 226,
as shown in FIG. 4, the seal 216 is free to move toward its
decompressed state, and the clam shells 220a/220b are pushed
proximally toward the opening 230. The movement causes a general
expansion of the inner cavity 218 (i.e., the cavity increases in
length), but causes a contraction (i.e., reduction in size) of the
volume of the constricted portion 267 of the seal 216. If the
volume change associated with the contraction of the constricted
portion 267 equals the volume change associated with the expansion
of the inner cavity 218, the fluid space or inner cavity will have
zero flow. If the increase in volume associated with the expansion
of the inner cavity 218 is greater than the reduction in volume
associated with the contraction of the constricted portion 267,
there will be a net gain in fluid space, resulting in an
undesirable negative flow toward the valve 210 through, e.g., a
catheter tip (not shown). If the reduction in volume associated
with the contraction of the constricted portion 267 is greater than
the increase in volume associated with the expansion of the inner
cavity 218, there will be a desirable positive flow from the valve
210 through the catheter tip (not shown). Thus, for the valve 210
to be a positive-flow valve requires that the clam shells be
configured to allow greater expansion of the constricted portion
267 (i.e., an increase in fluid volume in that area of the seal
216) than the general contraction volume change associated with the
expansion of the inner cavity 218 of the seal 216 upon compression
and, hence, greater contraction (i.e., decrease in fluid volume
within that area of the seal) of the constricted portion 267 than
the general expansion (i.e., increase in fluid volume in that area
of the seal) of the seal 216 upon decompression. In other words,
for the valve 210 to induce positive flow upon disconnection of the
medical implement 238 therefrom, the total fluid volume within the
valve 210 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 the valve 210 causes
fluid to flow towards the catheter/patient, preventing blood from
being drawn into the catheter.
[0063] That the valve 210 is advantageously configured to be a
positive-flow valve 210 eliminates any dead space during
decompression of the seal 210 as the syringe 238 is withdrawn, as
illustrated in FIG. 4. Furthermore, as the syringe 238 is
withdrawn, the slit 259 remains open until the very end, i.e.,
until the seal cap 248 is squeezed by the circular opening 230 at
the top of the upper conduit 226. This further assists in
eliminating dead space and avoiding backflash. This feature is
particularly advantageous in the case where the valve 210 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.
[0064] As the seal 216 is free to move to its decompressed state,
it essentially fills the opening 230. The ability of the seal 216
to return to its original shape and be deformed in its decompressed
state is determined by the resiliency of the material used to
prepare the seal 216. Advantageously, the ability of the seal 216
to return to its decompressed state is facilitated by the spring
222 and the gaps between the wall portions 258 of the seal 216. The
ability of the seal 216 to deform reversibly and return to its
decompressed state is particularly useful because (1) it
immediately stops fluid flow through the valve 210, and (2) it
maintains sterility of the valve.
[0065] The ability of the seal 216 to return reversibly to its
decompressed state permits reuse of the valve 210. Following
disconnection, and before reuse, the surface 250 of the seal cap
248 is essentially flush with the opening 230 of the housing 212.
Thus, this flush surface 250 can advantageously be sterilized with
alcohol or other surface-decontaminating substances. The support
member 214 and body 212 advantageously shield both connections from
the surrounding environment to protect the sterility of the
connection.
[0066] A cover cap (not shown) can be supplied to fit over the
upper conduit 226 as further protection for the surface 250 of the
seal cap 248 when not in use. Such a cover cap, however, is not
needed to maintain sterility since the seal 216 may be swabbed with
a disinfectant before and/or after each use. Reversibility of the
seal 216 makes the valve 210 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 the valve 210
disclosed herein. The reversibility of the valve 210 permits
multiple fluid lines to be successively added, for example, to a
fluid line in direct communication with a patient's vein. Since the
valve 210 is easily sterilized and sealable, fluid lines can be
added and removed without disconnecting venous contact of the
catheter.
[0067] The valve body 212 and support member 214 are preferably
prepared from a hard plastic, but it is additionally contemplated
that the valve 210 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 the seal 216 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.
[0068] As shown in FIG. 4, another feature of the invention is that
the upper ledge 234 confines the movement of the shoulder 252
toward the opening 250 to prevent the seal 216 from being blown
through the opening 230 under high pressure in the cavity 218. This
makes the valve 210 particularly suited for high pressure
applications.
Second Embodiment
[0069] In a second embodiment of the present invention illustrated
in FIGS. 6 and 7, the valve 310 includes a valve body or housing
312, a support member 314, a skirt 316, a seal 318, a resilient
member 320, and a pair of clam shells 322a/322b. The housing 312 is
desirably similar to the housing 212 of FIG. 4 and has a tapered
side wall 324.
[0070] Referring to FIGS. 6 and 7, the second embodiment of the
valve 310 has a bell-shaped skirt 316. The skirt 316 has an annular
ring 328 which is disposed toward an inner conduit 330 of the
support member 314. The skirt 316 creates a shield for the inner
conduit 330. This inner conduit 330 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. The support member
314 serves as a support and attachment device for the seal 318 by
holding the seal 318 in place inside the housing 312.
[0071] The support member 314 also serves as a support and
attachment device for the skirt 316. As best seen in FIG. 6, the
support member 314 has an edge portion 332 which engages a ledge
334 of the skirt 316 in assembly. This attachment secures the skirt
316 in place. The skirt 316 desirably includes a Luer-Lock portion
336 that enables the valve 310 to be removably attached to, for
example, a fluid line or catheter connected to a patient. It is
noted that the valve 310 in this embodiment includes a skirt 316
separate from the housing 312 for ease of assembly. A different
embodiment can provide a unitary member which replaces the housing
312 and skirt 316. It is therefore contemplated that such an
embodiment would fall within the scope of this invention.
[0072] The seal 318 is similar to the seal 210 of FIG. 4. The seal
318 is also preferably silicon and has a similar seal cap 340 with
a precut slit 342, shoulder 344, and pressure responsive member
348. These components serve the same function as those of the seal
210. Instead of a side wall formed with wall portions 258, the seal
318 has a side wall 350 that is generally circular cylindrical and
has a distal portion 352 that is sized to be slip-fitted with the
proximal end 354 of the inner conduit 330 of the support member
314. During compression of the seal 318, the side wall 350 simply
slides over the proximal end 354 of the inner conduit 330, forming
a fluid-tight seal therewith. The seal 318 defines an inner cavity
358 above the proximal end 354 of the inner conduit 330. The inner
cavity 358 forms an expandable fluid space inside the valve 310.
The inner conduit 330 and inner cavity 358 comprise aligned hollow
tubes in fluid communication with each other when the precut slit
342 of the seal 318 opens during compression of the seal 310.
[0073] Similar in form and function to the clam shells 220a/220b of
FIGS. 4 and 5, the clam shells 322a/322b are constructed to cause
an increase in fluid space upon insertion of a medical implement
into the valve 310 and a decrease in fluid space upon withdrawal of
the medical implement such as a syringe 362 partially shown in
phantom in FIG. 7. The internal surfaces 364a/364b of the clam
shells desirably have longitudinal grooves that cooperate with one
another to squeeze a portion of the seal side wall 350 to form a
constricted portion 366 thereof.
[0074] Instead of the spring 222 in FIG. 4, the second embodiment
employs the resilient member 320 disposed between the clam shells
322a/322b and the support member 314. The resilient member 320
advantageously is inert and impermeable to fluid such as silicon,
and includes wall portions 368 which deform in an accordion-like
fashion and assist in the reformation of the seal 318 to close the
housing opening 370 upon withdrawal of the syringe 362. The
resilient member 320 thus is similar in construction with and
serves the same function as the spring 222 of the seal 210 of FIGS.
4 and 5. It is contemplated that a spring (not shown) similar to
the spring 222 of FIG. 4 may be used in place of the resilient
member 320, as may other suitable structures known to those of
skill in the art.
[0075] As shown in FIGS. 6 and 7, the resilient member 320 has a
base 346. The base 346 fits snugly and securely within an annular
groove 374 provided in the housing 312 and an annular groove 377
provided in the support member 314, as shown in FIG. 6. The annular
grooves 376,377 hence form a locking mechanism to support and
secure the resilient member 320 within the housing 312. The
shoulder 344 engages an upper ledge 382 provided in an upper
conduit 384 of the housing 312 such that the upper ledge 382
confines the movement of the shoulder 344 toward the opening 370 to
prevent the seal 318 from being blown through the opening 370 under
high pressure in the inner cavity 358 of the seal 318.
[0076] The resilient member 320 is desirably relaxed or slightly
compressed longitudinally in the decompressed state (FIG. 6), and
compressed longitudinally in the compressed state (FIG. 7). The
resilient member 320 is desirably not attached or bonded to either
of the clam shells 322a/322b or the housing 312.
[0077] FIG. 7 illustrates compression and FIG. 6 illustrates
decompression during valve activation. In the compressed state, the
syringe 362 is placed on the seal cap 340 inside the opening 370 of
the housing 312, and the application of pressure on the syringe 362
creates pressure on the seal cap 340. The downward pressure pushes
the seal cap 340 away from the circular opening 370 and toward the
distal lower portion of the housing 312 which has a larger inner
diameter, thereby allowing the precut slit 342 to open. The side
wall 350 slides over the proximal end 354 of the inner conduit 330,
and the resilient member 320 deforms in an accordion-like manner,
storing potential energy of the compression. Fluid is able to flow
into the syringe 362, or vice versa, depending on whether fluid is
to be withdrawn from the patient or medication injected into the
patient.
[0078] The compression of the seal 318 shown in FIG. 7 generally
causes a contraction or reduction in the volume of the inner cavity
358 of the seal 318. The valve 310 has a net gain in volume of the
inner cavity 318, however, because the general reduction in volume
within the inner cavity 358 is less than an increase in volume
within the constricted portion 366 of the inner cavity 358 defined
by the clam shells 322a/322b. The expansion results from the
movement of the clam shells 322a/322b apart from one another during
compression, facilitated by the tapered side wall 324 of the
housing 312.
[0079] FIG. 6 illustrates the valve after withdrawal of the syringe
362. The seal 318 returns to its decompressed state and essentially
fills the opening 370, and the clam shells 322a/322b are pushed
proximally toward the opening 370 by the resilient member 320.
Because of the contraction of the inner cavity 358 at the
constricted portion 366 by the clam shells 322a/322b, there is a
net loss or reduction in fluid space, resulting in a positive flow
from the valve 310 through, e.g., a catheter tip (not shown). The
positive-flow valve 310 advantageously eliminates any dead space
during decompression of the seal 318. This is further assisted by
the seal 318 with the slit 342 remaining open until the very end,
i.e., until the seal cap 340 is squeezed by the upper conduit
384.
[0080] In addition, the valve 310 can be reused because the seal
318 can return reversibly in the decompressed state. The seal
surface 340 is also swabbable for sterility. Other features of the
valve 310 are discussed previously in connection with the first
embodiment of this invention and will not be repeated.
Third Embodiment
[0081] As shown in FIGS. 8 and 9, a third embodiment of the valve
410 of the present invention comprises a valve body or housing 412,
a support member 414, a flexible tubing 416, a seal 418, a ring
member 420, a pair of clam shells 422a/422b, and a spring 424. The
flexible tubing 416 may be connected to a catheter (not shown) and,
together with the seal 418, defines an inner cavity 426. The inner
cavity 426 forms an expandable fluid space of the valve 410. The
clam shells 422a/422b desirably are substantially the same as the
clam shells 220a/220b of FIG. 4 and are constructed to cause the
fluid space within the valve 410 to increase upon insertion of a
medical implement and to decrease upon withdrawal of the medical
implement such as a syringe 428 partially shown in phantom in FIG.
9. The housing 412 is desirably similar to the housing 212 of FIG.
4.
[0082] The support member 414 has a hollow center 430 which
supports the flexible tubing, and a proximal end 432 which encloses
a distal end 434 of the housing 412. The support member 414
desirably locks onto the housing 412 via any method known to those
of skill in the art. The proximal end 432 of the support member 414
supports the spring 424, which in turn supports the clam shells
422a/422b and seal 418.
[0083] The seal 418 is prepared from a resilient material that is
flexible, inert, and impermeable to fluid, such as silicon.
Referring to FIG. 8, the seal 418 is substantially similar to the
seal 210 of FIG. 4, with a portion of the side wall 438 cut off
near the shoulder 440 region. As a result, the side wall 438 of the
seal 418 is substantially shorter than the side wall 254 of the
seal 210 in FIG. 4. A distal end 442 of the side wall 254 is
attached, preferably by adhesive, to a proximal end 444 of the
flexible tubing 416. The distal end 442 abuts the ring member 420
which is disposed between the seal 418 and the clam shells
422a/422b and attached at its inner surface 446 to a portion of the
tubing 416, desirably also by adhesive. Other suitable means of
attachment may be used. The ring member 420 is desirably made of
polycarbon.
[0084] The clam shells 422a/422b desirably form a sliding contact
at their proximal ends with the ring member 420 for ease of
assembly, but may alternatively be affixed to the ring member 420
by adhesive or similar means. The clam shells 422a/422b are
desirably the same as the clam shells 220a/220b of FIG. 4, having
tapered external surfaces 450a/450b to cooperate with the tapered
side wall portion 452 of the housing 412 for sliding and grooved
internal surfaces 454a/454b that cooperate with one another to
squeeze a portion of the tubing 416 to form a constricted portion
456.
[0085] The spring 424 is substantially the same as the spring 222
of FIG. 4 and serves the same function, being disposed between the
distal ends of the clam shells 422a/422b and the proximal end 432
of the support member 414. In the decompressed state shown in FIG.
8, the spring 424 may be relaxed or in slight compression to exert
a force on the seal 418 through the clam shells 422a/422b to keep
the slit 466 in the seal cap 460 closed. During insertion of the
syringe 428, the spring 424 is compressed and stores potential
energy from the compression, as illustrated in FIG. 9. Upon
withdrawal of the syringe 428, the spring 424 releases the
potential energy and pushes the clam shells 422a/422b proximally to
close the seal 418, as shown in FIG. 8. The spring 424 is
preferably not attached or bonded to either the clam shells
422a/422b or the support member 414 for ease of assembly. The
spring 424 can be a helical spring or any other suitable spring
known to those with skill in the art.
[0086] FIG. 9 shows the compressed state of the valve 410 upon
insertion of the syringe 428. In the compressed state, the syringe
428 is placed on the seal cap 460 inside the opening 464 of the
housing 412 and the application of pressure on the syringe 428
creates pressure on the seal cap 460. The downward pressure pushes
the seal cap 460 away from the circular opening 464 and toward the
distal end of the housing 412, which has a larger inner diameter,
thereby allowing the precut slit 466 of the seal cap 460 to open.
The resilient tubing 416 and the clam shells 422a/422b also move
distally as the spring 424 deforms in compression, storing
potential energy. Fluid is able to flow into the syringe 428, or
vice versa, depending on whether fluid is to be withdrawn from the
patient or medication injected into the patient.
[0087] The compression of the seal 418 shown in FIG. 9 generally
causes a reduction in the volume of the inner cavity 426 formed by
the seal 418 and tubing 416. However, because of an expansion of
the constricted portion 456 defined by the clam shells 422a/422b an
increase in fluid volume is created which is greater than the
general reduction in fluid volume within the inner cavity 426, the
valve 410 has a net gain in fluid volume. The increase in fluid
volume results from the movement of the clam shells 422a/422b apart
from one another during seal compression, facilitated by the
tapered side wall 452 of the housing 412 and resiliency of the
tubing 416.
[0088] FIG. 8 illustrates the valve 410 after withdrawal of the
syringe 428. The seal 418 returns to its decompressed state and
essentially fills the opening 464, and the clam shells 422a/422b
are pushed proximally toward the opening 464 by the spring 424.
Because of the contraction of the inner cavity 426 at the
constricted portion 456 by the clam shells 422a/422b, there is a
net loss in fluid space, resulting in a positive flow from the
valve 410 through, e.g., a catheter tip (not shown). The
positive-flow valve 410 advantageously eliminates any dead space
during decompression of the seal 418. This is further assisted by
the seal 418, with the slit 466 remaining open until the very end,
i.e., until the seal cap 460 is squeezed by upper conduit 470.
[0089] In addition, the valve 410 can be reused because the seal
418 can return reversibly to the decompressed state. The seal
surface 472 is also swabbable for sterility. Other features of the
valve 410 are discussed previously in connection with the earlier
embodiments of this invention and will not be repeated.
Fourth Embodiment
[0090] A fourth embodiment of the present invention is illustrated
in FIGS. 10 and 11. As illustrated therein, a valve 510, comprises
a valve body or housing 512, a support member 514, a skirt 516, a
retaining member 518, a seal 520, a pair of clam shells 522a/522b,
and a resilient member 524. The valve 510 has several features that
are the same or similar to those of the valve 310 of FIGS. 8 and 9,
having a similar resilient member 524 and clam shells 522a/522b.
The clam shells 522a/522b have internal surfaces 526a/526b that
cooperate with one another to squeeze a portion of the seal side
wall 528 to form a constricted portion 530 thereof.
[0091] The seal 510 is preferably made of silicon and has a seal
cap 532 with a precut slit 534, shoulder 536, lower lip 538, and
pressure responsive member 540 that are similar to the seal 210 of
FIG. 4. These components serve the same function as those of the
seal 210. The side wall 528 may be formed with ringed wall portions
258, as in the seal 210, but FIG. 4 shows the side wall 528 that is
generally circular cylindrical. The seal 520 defines an inner
cavity 542 which forms an expandable fluid space inside the valve
510. During compression of the seal 520, the side wall 528 deforms
outwardly into a circumferential cusp or bulge 544 in the
unconstricted region between the clam shells 522a/522b and the
support member 514. The side wall 528 returns to its decompressed
shape upon decompression of the seal 520. The seal 520 is desirably
relaxed longitudinally in the decompressed state (FIG. 10), and
compressed longitudinally in the compressed state (FIG. 11).
Alternatively, the seal 520 may be stretched longitudinally in
tension by the resilient member 524 in the decompressed state and
be relaxed or slightly compressed longitudinal in the compressed
state.
[0092] Referring to FIG. 10, the skirt 516 is a bell-shaped skirt
that is similar to the skirt 316 of FIG. 8. The skirt 516 creates a
shield for an inner conduit 548 of the support member 514. The
inner conduit 548 may be connected to a terminal end of a catheter
(not shown) which has an open end that is generally inserted into a
patient. The support member 514 serves as a support and attachment
device for the seal 520 by holding the seal 520 in place inside the
housing 512.
[0093] The support member 514 also serves as a support and
attachment device for the skirt 516. Similar to the valve 310 of
FIG. 8, the support member 514 shown in FIG. 10 has an edge portion
550 which engages a ledge 552 of the skirt 516 in assembly. This
attachment secures the skirt 516 in place. The skirt 516 desirably
includes a Luer-Lock portion 554 that enables the valve 510 to be
removably attached to, for example, a fluid line or catheter
connected to a patient.
[0094] The retaining member 518 is desirably provided to secure the
lower lip 538 of the seal 520 and support the resilient member 524.
The retaining member 518 is held inside the housing 512 by the
support member 514, and is provided for ease of assembling the
valve 510. The retaining member 518 has an annular groove 556, and
the support member 514 has an annular groove 558. The annular
grooves 556,558 form a locking mechanism to support and secure the
seal 520 within the housing 512 by engaging the lower lip 538
snugly with the grooves 556,558. It is noted that a different
embodiment may provide a unitary member which replaces the support
member 514 and the retaining member 518. It is therefore
contemplated that such an embodiment would fall within the scope of
this invention.
[0095] FIG. 11 illustrates compression and FIG. 10 illustrates
decompression during valve activation. In the compressed state, a
medical implement such as the syringe 562 partially shown in
phantom is placed on the seal cap 532 inside the opening 564 of the
housing 512, and the application of pressure on the syringe 562
creates pressure on the seal cap 532. The downward pressure pushes
the seal cap 532 away from the circular opening 564 and toward the
lower portion of the housing 512, which has a larger inner
diameter, thereby allowing the precut slit 534 to open. The side
wall 528 deforms outwardly at the unconstricted region into a
circumferential cusp 544, and the resilient member 524 deforms in
an accordion-like manner, storing potential energy of the
compression. Fluid is able to flow into the syringe 562, or vice
versa, depending on whether fluid is to be withdrawn from the
patient or medication injected into the patient.
[0096] The compression of the seal 520 shown in FIG. 11 generally
causes a reduction in the fluid volume of the inner cavity 542 of
the seal 520. The valve 510 has a net gain in volume of the inner
cavity 542, however, because the general reduction in volume within
the inner cavity 542 is less than the increase in volume within the
constricted portion 530 as defined by the clam shells 522a/522b and
of the cusp 544 at the unconstricted region of the seal 520.
[0097] FIG. 10 illustrates the valve 510 after withdrawal of the
syringe 562. The seal 520 returns to its decompressed state and
essentially fills the opening 564, and the clam shells 522a/522b
are pushed back up toward the opening 564 by the resilient member
524. Because of the contraction of the inner cavity 542 of the seal
520, there is a net loss in fluid space, resulting in a positive
flow from the valve 510 through, e.g., a catheter tip (not shown).
The positive-flow valve 510 advantageously eliminates any dead
space during decompression of the seal 520. This is further
assisted by the seal 520, with the slit 534 remaining open until
the very end, i.e., until the seal cap 532 is squeezed by the
circular opening 564 at the top of the upper conduit 570.
[0098] In addition, the valve 510 can be reused because the seal
520 can return reversibly in the decompressed state. The seal
surface 572 is also swabbable for sterility. Other features of the
valve 510 are discussed previously in connection with the earlier
embodiments of this invention.
Fifth Embodiment
[0099] FIGS. 12 and 13 show a fifth embodiment valve 610 in
accordance with the present invention, the valve 610 comprising a
valve body or housing 612, a seal 614, a ring member 616, and a
spring 618. The housing 612 is similar to the housing 212 of FIG.
4, with a circular opening 620, and a tapered side wall 622, but
may have a straight side wall instead. The seal 614 is similar to
the seal 318 of FIG. 8, having a substantially cylindrical side
wall 624 and defining an inner cavity 626 which forms an expandable
fluid space inside the valve 610. The side wall 624 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 a syringe 630 partially shown in
phantom in FIG. 13. The distal portion of the seal 614 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 the
support member 214 shown in FIG. 15.
[0100] The ring member 616 is desirably an annular disk 616 made of
a hard plastic and disposed between a shoulder 634 of the seal 614
and a proximal end 636 of the spring 618. The ring member 616
serves as a constraint for the seal 614 during compression and
efficiently transfers the compressive force to the spring 618,
assisting in the deformation of the seal 614. During decompression,
the ring member 616 efficiently transfers the spring force to the
seal cap 638 of the seal 614 to close the opening 620. Although the
ring member 616 facilitates the deformation and reformation of the
seal 614, it is not necessary for the seal 614 to work. In that
case, the spring 618 will contact the seal cap 638 directly.
[0101] The spring 618 is substantially the same as the spring 222
of FIG. 4 and serves the same function, being disposed between the
ring member 616 and a distal end 642 of the housing 612. In an
alternative embodiment, the distal end 642 may be a separate
component from the housing 612 for ease of assembly. In the
decompressed state shown in FIG. 12, the spring 618 may be relaxed
or be in slight compression to exert a force on the seal 614
through the ring member 616 to keep the seal 614 closed. During
insertion of the syringe 630, the spring 618 is compressed and
stores potential energy from the compression, as illustrated in
FIG. 13. Upon withdrawal of the syringe 630, the spring 618
releases the potential energy and pushes the ring member 616 to
close the seal 616 as shown in FIG. 12. The spring 618 is
preferably not fixed with either the ring member 616 or the distal
end 642 of the housing 612 for ease of assembly. The spring 618 can
be a helical spring or any other suitable spring known to those
with skill in the art.
[0102] The side wall 624 of the seal 614 is constrained by the ring
member 616 and housing 612, and is substantially relaxed in the
decompressed state. During compression of the seal 614, the side
wall 624 bulges in the unconstrained region between the ring member
616 and the distal end 642 of the housing 612, causing an increase
in the fluid space within the valve 610. The side wall 624 returns
to its decompressed shape upon decompression of the seal 614.
Alternatively, the side wall 624 may be stretched in tension by the
spring 618 in the decompressed state and goes through a relaxed
position before deforming under compression to its bulged
condition.
[0103] FIG. 13 illustrates compression and FIG. 12 illustrates
decompression during valve activation. In the compressed state, the
syringe 630 is placed on the seal cap 638 inside the opening 620 of
the housing and the application of pressure on the syringe 630
creates pressure on the seal cap 638. The downward pressure pushes
the seal cap 638 and the ring member 616 away from the circular
opening 620 and toward the lower portion of the housing 612 which
has a larger inner diameter, thereby allowing the precut slit 646
of the seal cap 638 to open. The side wall 624 deforms outwardly
and bulges at the unconstricted region, as the spring 618 is
compressed, storing potential energy of the compression. Fluid is
able to flow into the syringe 630, or vice versa, depending on
whether fluid is to be withdrawn from the patient or medication
injected into the patient. The compression of the seal 614 shown in
FIG. 13 results in a net gain in volume of the inner cavity.
[0104] FIG. 12 illustrates the valve 610 after withdrawal of the
syringe 630. The seal 614 returns to its decompressed state and
essentially fills the opening 620, and the ring member 616 is
pushed back up toward the opening 620 as the spring 618 releases
its potential energy. Because of the contraction of the inner
cavity 626 of the seal 614, there is a net loss in fluid space,
resulting in a positive flow from the valve 610 through, e.g., a
catheter tip (not shown). The positive-flow valve 610
advantageously eliminates any dead space during decompression of
the seal 614. This is further assisted by the seal 614 with the
slit 646 remaining open until the very end, i.e., until the seal
cap 638 is squeezed by the circular opening 620 at the top of the
upper conduit 650 of the housing 612.
[0105] In addition, the valve 610 can be reused because the seal
614 can return reversibly in the decompressed state. The seal
surface 652 is also swabbable for sterility. Other features of the
valve 610 are discussed previously in connection with the earlier
embodiments of this invention.
Sixth Embodiment
[0106] A sixth embodiment of a valve 710 is illustrated in FIGS. 14
and 15. The valve 710 comprises a valve body or housing 712 and a
seal 714. The housing 712 has an upper conduit 716 near a proximal
end with a circular opening 718 that is preferably adapted to
receive a medical implement. A side wall portion 720 is protruded
to facilitate deformation of the seal 714. A distal end 724 of the
housing 712 forms a lower passage 726 (partially shown) which
supports and constrains a distal portion 728 of the seal 714, 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 the housing 712 and support the seal 714, such
as those shown in FIG. 4 (214) or FIG. 12 (514).
[0107] The seal 714 is generally similar to the seal 614 of FIGS.
12 and 13, and has a substantially cylindrical side wall 721,
although the side wall 732 may have a slight bulge 733 as shown in
FIG. 14. It defines an inner cavity 734 which forms an expandable
fluid space inside the valve 710. In the decompressed state, the
seal 714 is constrained by the upper conduit 716 and lower passage
726 of the housing 712, 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 the syringe 730 partially shown in
phantom in FIG. 15. During compression of the seal 714, the side
wall 732 bulge in the unconstrained region between the upper
conduit 716 and lower passage 726 and the bulge 738 is
substantially round. The side wall 732 return to its decompressed
shape upon decompression of the seal 714.
[0108] FIG. 15 illustrates compression and FIG. 14 illustrates
decompression during valve activation. In the compressed state, the
syringe 730 is placed on the seal cap 742 of the seal 714 inside
the opening 718 of the housing 712 and the application of pressure
on the syringe 730 creates pressure on the seal cap 742. The
downward pressure pushes the seal cap 742 away from the circular
opening 718 and toward the protruded portion 720 of the housing 712
which has a larger inner diameter, thereby allowing the precut slit
746 of the seal cap 742 to open. The side wall 732 deforms
outwardly and bulges at the unconstricted region 738, storing
potential energy of the compression. Fluid is able to flow into the
syringe 730, or vice versa, depending on whether fluid is to be
withdrawn from the patient or medication injected into the patient.
The compression of the seal 714 shown in FIG. 15 generates a net
gain in volume of the inner cavity.
[0109] FIG. 14 illustrates the valve 710 after withdrawal of the
syringe 730. The seal 714 returns to its decompressed state and
essentially fills the opening 718. Because of the contraction of
the inner cavity 734 of the seal, there is a net loss in fluid
space, resulting in a positive flow from the valve 710 through,
e.g., a catheter tip (not shown). The positive-flow valve 710
advantageously eliminates any dead space during decompression of
the seal 714. This is further assisted by the seal 714 with the
slit 746 remaining open until the very end, i.e., until the seal
cap 742 is squeezed by the circular opening 718 at the top of the
upper conduit 716.
[0110] In addition, the valve 710 can be reused because the seal
710 can return reversibly in the decompressed state. The seal
surface 748 is also swabbable for sterility. Other features of the
valve 710 are discussed previously in connection with the earlier
embodiments of this invention.
Seventh Embodiment
[0111] FIGS. 16 and 17 illustrate a valve 710 in accordance with a
seventh embodiment of the present invention, the valve 756
comprising a valve body or housing 758 and a seal 760 that are
substantially the same as the housing 712 and seal 714 of FIGS. 14
and 15, with a distal portion 762 of the seal 760 connected to a
fluid line such as a catheter (not shown). The seal 760, however,
is configured to deform upon compression into a diamond-shaped cusp
764 instead of a round bulge 738 as illustrated in FIGS. 14 and 15.
This type of construction may facilitate deformation and
reformation of the seal 760, and may be more easily formed. The
valve activation of this embodiment is virtually identical to that
in FIGS. 14 and 15, except for the deformed shape of the seal side
wall 770. 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 the syringe 774
partially shown in phantom in FIG. 28.
Eighth Embodiment
[0112] As illustrated in FIGS. 18 and 19, an eighth embodiment
valve 810 of the present invention is similar to the embodiments
shown in FIGS. 14-17. The valve 810 also includes a housing 812
having an internal cavity 814 with an upper conduit 816, and a seal
818 disposed inside the internal cavity 814 and having an inner
cavity 820 that defines a fluid space. The housing 812 has a distal
end 824 which supports a side wall 826 of the seal 818. A distal
portion 828 of the seal 818 is connected to a fluid line such as a
catheter (not shown). The pressure at the inner cavity 820 of the
seal 818 is P1. Between the housing 812 and the seal 818 is an
enclosed pressure chamber 832 at pressure P2. The valve activation
utilizes the pressure difference between P2 in the pressure chamber
832 and P1 in the inner cavity 820 of the seal 818.
[0113] Upon insertion of a medical implement such as a syringe 836
shown in phantom in FIG. 19, the pressure at the inner cavity 820
of the seal 818 increases from P1 to P3 and the fluid space inside
the seal 818 expands from the decompressed state of FIG. 18. The
expansion of the fluid space results primarily from a difference in
pressure between P3 and P2. This valve 810 is particularly
advantageous in the case where the side wall 826 of the seal 818
deforms without storing substantial potential energy. For instance,
the side wall 826 of the seal 818 may deform without substantial
resistance or resiliency such as a membrane, or the seal is not
constrained longitudinal by the distal portion 824 of the housing
812 and may slide in and out of the internal cavity 814 of the
housing 812 through the distal end 824.
[0114] FIG. 19 illustrates compression and FIG. 18 illustrates
decompression during valve activation. In the compressed state, the
syringe 836 is placed on the seal cap 838 of the seal 818 inside
the opening 840 of the housing 812 and the application of pressure
on the syringe creates pressure on the seal cap 838. The downward
pressure pushes the seal cap 838 away from the circular opening 840
and toward the lower portion of the housing 812 which has a larger
inner diameter, thereby allowing the precut slit 844 of the seal
cap 838 to open. The entry of the fluid causes the pressure at the
inner cavity 814 of the seal 812 to increase to P3. As a result,
the side wall 826 deforms outwardly and bulges at the unconstricted
region 848. Potential energy is stored in the change in pressure
differential between the inner cavity 820 and the pressure chamber
832. The side wall 826 of the seal 818 need not deform and store
energy, but may do so. Fluid is able to flow into the syringe 836,
or vice versa, depending on whether fluid is to be withdrawn from
the patient or medication injected into the patient. The
compression of the seal 818 shown in FIG. 19 causes a net gain or
increase in fluid volume within the inner cavity.
[0115] FIG. 18 illustrates the valve 810 after withdrawal of the
syringe 836. The seal 818 returns to its decompressed state and
essentially fills the opening 840, and the pressure in the inner
cavity 820 returns to P1 and releases the potential energy. Because
of the contraction of the inner cavity 820 of the seal 818, there
is a net loss in fluid space, resulting in a positive flow from the
valve 810 through, e.g., a catheter tip (not shown). The
positive-flow valve 810 advantageously eliminates any dead space
during decompression of the seal 818. This is further assisted by
the seal 818 with the slit 844 remaining open until the very end,
i.e., until the seal cap 838 is squeezed by the circular opening
840 at the top of the upper conduit 816.
[0116] In addition, the valve 810 can be reused because the seal
818 can return reversibly in the decompressed state. The seal
surface 854 is also swabbable for sterility. Other features of the
valve 810 are discussed previously in connection with the earlier
embodiments of this invention.
Ninth Embodiment
[0117] A ninth embodiment of a valve 910 comprising a housing 912,
a support member 914, a skirt 916, a seal 918, and a scissor-like
cross member 920, is depicted in FIGS. 20 and 21. The housing 912
has an upper conduit 924 with a circular opening 926. The support
member 914 has an inner conduit 928 which is connected to a fluid
line such as a catheter (not shown). The seal 918 has a side wall
930 desirably formed of alternating wall portions 932 and defines
an inner cavity 934 which forms an expandable fluid space inside
the valve 910. The cross member 920 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 the syringe 936 partially shown in phantom in
FIG. 21.
[0118] The cross member 920 has two longitudinal member 940
attached together which rotates with respect to one another, and is
desirably made of a hard material such as a hard plastic. The cross
member 920 is disposed at a constricted portion 942 of the seal 918
within the inner cavity 934 with the longitudinal members 940
preferably substantially disposed vertically. The ends 944 of the
longitudinal members 940 are desirably attached to the side wall
930 as shown in FIG. 20. The longitudinal members 940 rotate to a
substantially horizontal orientation upon compression by the
insertion of the syringe 936 as shown in FIG. 21. This rotation is
referred to as the deformation of the cross member 920. The
longitudinal members 940 may be attached to rotate freely with
respect to one another. Alternatively, the longitudinal members 940
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 the syringe 936 as shown in FIG.
20, the longitudinal members 940 return to the substantially
vertical positions, referred to as the reformation of the cross
member 920. The longitudinal members 940 are desirably longitudinal
plates 940 with sufficient width to expand the constricted portion
942 of the seal 918 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.
[0119] FIG. 21 illustrates compression and FIG. 20 illustrates
decompression during valve activation. In the compressed state, the
syringe 926 is placed on the seal cap 950 of the seal 918 inside
the opening 926 of the housing 912 and the application of pressure
on the syringe 936 creates pressure on the seal cap 950. The
downward pressure pushes the seal cap 950 away from the circular
opening 926 and toward the lower portion of the housing 912 which
has a larger inner diameter, thereby allowing the precut slit 952
of seal cap 950 to open. The side wall 930 of the seal 918 deforms
in an accordion-like manner, and the cross member 920 deforms and
opens up the constricted portion 922 of the seal 918, storing
potential energy of the compression. Fluid is able to flow into the
syringe 936, or vice versa, depending on whether fluid is to be
withdrawn from the patient or medication injected into the patient.
The compression of the seal 918 and deformation of the cross 920
shown in FIG. 21 generally causes a contraction of the volume of
the inner cavity 934 of the seal 918. The valve 910 has a net gain
in volume of the inner cavity 934, however, because the general
contraction of the inner cavity 934 is less than by the expansion
of the constricted portion 942 pushed apart by the cross member
920. The expansion results from the movement of the longitudinal
members 940 of the cross member 920 during compression.
[0120] FIG. 20 illustrates the valve 910 after withdrawal of the
syringe 936. The seal 918 returns to its decompressed state and
essentially fills the opening 926, and the cross member 920 reforms
to allow the constricted region 942 of the seal 918 to narrow.
Because of the contraction of the inner cavity 934 at the
constricted portion 942, there is a net loss in fluid space,
resulting in a positive flow from the valve 910 through, e.g., a
catheter tip (not shown). The positive-flow valve 910
advantageously eliminates any dead space during decompression of
the seal 918. This is further assisted by the seal 918 with the
slit 952 remaining open until the very end, i.e., until the seal
cap 950 is squeezed by the circular opening 926 at the top of the
upper conduit 924.
[0121] In addition, the valve 910 can be reused because the seal
918 can return reversibly in the decompressed state. The seal
surface 960 is also swabbable for sterility. Other features of the
valve 910 are discussed previously in connection with the earlier
embodiments of this invention.
Tenth Embodiment
[0122] FIGS. 22 and 23 illustrate a valve 1010 in accordance with a
tenth embodiment of the present invention, the valve 1010
comprising a valve body or housing 1012, a support member 1014
(partially shown), a seal 1016, a ring member 1018, a resilient
reel 1020, and a scissor-like cross member 1022. The support member
1014 has an inner conduit (not shown) which is connected to a fluid
line such as a catheter (not shown). The seal 1016 has a seal cap
1028 with slit 1030, shoulder 1032, and pressure responsive member
1034.
[0123] The ring member 1018 forms a sliding contact with a distal
end 1036 of the seal 1016 and is preferably made from a hard
plastic. The ring member 1018 desirably has a shoulder 1038 which
is constrained by a ledge 1040 of the housing 1012 in the upward
direction. The distal end of the ring member 1018 contacts an upper
flange 1044 of the resilient reel 1020 and facilitates transfer of
the compressive force due to insertion of a medical implement to
cause deformation of the reel 1020. The reel 1020 is made from a
material that is flexible, inert, and impermeable to fluid, such as
silicon. It has a lower flange 1046 that is supported and secured
by the support member 1014 and a central body portion 1048 that is
substantially cylindrical. The seal 1016, ring member 1018, and
resilient reel 1020 define an inner cavity 1050 which forms an
expandable fluid space inside the valve 1010.
[0124] The cross member 1022 is substantially the same of the cross
member 920 of FIGS. 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 the syringe 1054 partially shown in phantom in
FIG. 23. The cross member 1022 has two longitudinal members 1056
rotatably attached together. The cross member 1022 is disposed
adjacent the central body portion 1048 of the reel 1020 within the
inner cavity 1050 with the longitudinal members 1056 preferably
pointed toward the vertical direction and desirably attached to the
central body portion 1048 at its four ends 1058 as shown in FIG.
22. The longitudinal members 1056 rotate to a substantially
horizontal orientation upon compression by the insertion of the
syringe 1054 as shown in FIG. 23. This rotation is referred to as
the deformation of the cross member 1022. The longitudinal members
1050 may be attached to rotate freely with respect to one another.
Alternatively, the longitudinal members 1056 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 the syringe 1056 as shown in FIG. 22, the
longitudinal members 1056 return to the substantially vertical
positions, referred to as the reformation of the cross member 1022.
The longitudinal members 1026 are desirably longitudinal plates
1056 with sufficient width to open up the central body portion 1048
of the reel 1020 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.
[0125] FIG. 23 illustrates compression and FIG. 22 illustrates
decompression during valve activation. In the compressed state, the
syringe 1054 is placed on the seal cap 1028 inside the opening 1062
of the housing 1012 and the application of pressure on the syringe
1054 creates pressure on the seal cap 1028. The downward pressure
pushes the seal cap 1028 away from the circular opening 1062 and
toward the lower portion of the housing 1012 which has a larger
inner diameter, thereby allowing the precut slit 1030 to open. The
ring member 1018 moves toward the support member 1014 and
compresses the resilient reel 1020. The upper flange 1044 of the
resilient reel 1020 is pushed by the ring member 1018 toward the
lower flange 1046. The central body portion 1048 bulges outwardly
as the cross member 1022 deforms, storing potential energy of the
compression. Fluid is able to flow into the syringe 1054, or vice
versa, depending on whether fluid is to be withdrawn from the
patient or medication injected into the patient.
[0126] The compression of the seal 1016 and deformation of the
cross 1022 shown in FIG. 23 generally causes a reduction in the
volume of the inner cavity of the seal 1016. The valve 1010 has a
net gain in volume of the inner cavity 1050, however, because the
expansion of the central body portion 1048 of the flexible reel 120
causes an increase in fluid volume which reduction resulting in is
greater than the general contraction of the inner cavity 1050. The
expansion results from the movement of the longitudinal members
1056 of the cross member 1022 to open up the central body portion
1048 of the resilient reel 1020 during compression.
[0127] FIG. 22 illustrates the valve 1010 after withdrawal of the
syringe 1054. The seal 1016 returns to its decompressed state and
essentially fills the opening 1062, and the cross member 1022
reforms to allow the central body region 1048 of the resilient reel
1022 to narrow. Because of the contraction of the inner cavity 1050
at the central body portion 1048, there is a net loss in fluid
space, resulting in a positive flow from the valve 1010 through,
e.g., a catheter tip (not shown). The positive-flow valve 1010
advantageously eliminates any dead space during decompression of
the seal 1016. This is further assisted by the seal 1016 with the
slit 1030 remaining open until the very end, i.e., until the seal
cap 1028 is squeezed by the circular opening 1062 at the top of the
upper conduit 1066 of the housing.
[0128] In addition, the valve 1010 can be reused because the seal
1016 can return reversibly in the decompressed state. The seal
surface 1068 is also swabbable for sterility. Other features of the
valve 1010 are discussed previously in connection with the earlier
embodiments of this invention.
Eleventh Embodiment
[0129] An eleventh embodiment of a valve 1110 in accordance with
the present invention is illustrated in FIGS. 24 and 25, and
comprises a valve body or housing 1112 and a seal 1114. The housing
1112 has an upper conduit 1116 near a proximal end with a circular
opening 1118 that is preferably adapted to receive a medical
implement such as a syringe 1120 partially shown in phantom in FIG.
25. The housing 1112 has a lower conduit 1124 (partially shown)
near a distal end which is connected to a fluid line such as a
catheter (not shown). Disposed between the upper conduit 1116 and
lower conduit 1124 are protruded right and left side walls
1126a,1126b connected to resilient ribbed portions 1128a,1128b
which allow the side walls 1126a,1126b to be stretched outwardly
and reform inwardly in a substantially horizontal direction. Aside
from the resilient ribbed portions 1128a, 1128b, the rest of the
housing 1112 is desirably made of a firm material such as a hard
plastic.
[0130] The seal 1114 is generally similar to the seal 318 of FIG. 6
with a similar shoulder 1132, seal cap 1134, and pressure
responsive element 1136. The cylindrical side wall 350 of FIG. 6,
however, is replaced with a spreader 1140, which includes two legs
1142a, 1142b that extend from the shoulder 1132 outwardly at distal
ends 1144a, 1144b that bear against the protruded right and left
side walls 1126a,1126b, as best seen in FIG. 24. The distal end
1144a may be attached to the protruded side wall 1126a, and the
distal end 1144b may be attached to the protruded side wall 1126b,
by adhesives or other available means. An inner cavity 1150 is
formed by the seal 1114 and a distal portion 1152 of the housing
1112, and defines a fluid space of the valve 1110. During
compression of the seal 1114, the spreader 1140 extends further
outwardly and pushes the protruded side walls 1126a,1126b
outwardly. The seal 1114 and housing 1112 are configured and
dimensioned to assist in causing the fluid space to expand upon
insertion of the medical implement 1120 and to contract upon
withdrawal of the medical implement 1120.
[0131] FIG. 25 illustrates compression and FIG. 24 illustrates
decompression during valve activation. In the compressed state, the
syringe 1120 is placed on the seal cap 1134 inside the opening 1118
of the housing 1112 and the application of pressure on the syringe
1120 creates pressure on the seal cap 1134. The downward pressure
pushes the seal cap 1134 away from the circular opening 1118 and
toward the lower portion of the housing 1112 which has a larger
inner diameter, thereby allowing the precut slit 1156 oft he seal
cap 1134 to open. The spreader 1140 extends outwardly, stretching
the resilient ribbed portions 1128a, 1128b and pushing the
protruded right and left side walls 1126a,1126b of the housing 1112
outwardly, storing potential energy of the compression. Fluid is
able to flow into the syringe 1120, or vice versa, depending on
whether fluid is to be withdrawn from the patient or medication
injected into the patient. The compression of the seal 1114 and
deformation of the spreader 1140 shown in FIG. 36 results in a net
gain in volume of the inner cavity 1150.
[0132] FIG. 24 illustrates the valve 1110 after withdrawal of the
syringe 1120. The seal 1114 returns to its decompressed state and
essentially fills the opening 1118, and the spreader 1140 and
resilient ribbed portions 1128a,1128b reform to allow the protruded
right and left side walls 1126a,1126b to move inwardly. Because of
the contraction of the inner cavity 1150, there is a net loss in
fluid space, resulting in a positive flow from the valve 1110
through, e.g., a catheter tip (not shown). The positive-flow valve
1110 advantageously eliminates any dead space during decompression
of the seal 1114. This is further assisted by the seal 14 with the
slit 1156 remaining open until the very end, i.e., until the seal
cap 1134 is squeezed by the circular opening 1156 at the top of the
upper conduit 1116.
[0133] In addition, the valve 1110 can be reused because the seal
1114 can return reversibly in the decompressed state. The seal
surface 1160 is also swabbable for sterility. Other features of the
valve 1110 are discussed previously in connection with the earlier
embodiments of this invention.
Twelfth Embodiment
[0134] A twelfth embodiment valve 1210 is illustrated in FIGS. 26
and 27, and comprises a valve body or housing 1212, a support
member 1214 (partially shown), a seal 1216, a ring member 1218, and
a resilient reel 1226. The housing 1212, support member 1214, and
ring member 1218 are substantially the same as those shown in FIGS.
22 and 23. The housing 1212 has an upper conduit 1224 with a
circular opening 1226. The support member 1214 has an inner conduit
(not shown) which is connected to a fluid line such as a catheter
(not shown). The distal end 1228 of the ring member 1218 contacts
an upper flange 1232 of the resilient reel 1220 and facilitates
transfer of the compressive force due to insertion of a medical
implement such as a syringe to cause deformation of the reel 1220.
The reel 1220 further includes a central body portion 1234 and a
lower flange 1236 that is desirably supported and secured by the
support member 1214.
[0135] The seal 1216 is similar to the seal 1114 of FIGS. 24 and
25, and has a similar seal cap 1240 with slit 1242, shoulder 1244,
and pressure responsive member 1246. The seal 1246 has a spreader
1250 that extends from the shoulder 1244 outwardly and forms a
circular distal ring 1252 that bears against the central body
portion 1234 of the resilient reel 1220, as best seen in FIG. 26.
The distal ring 1252 may be attached to the central body portion
1234 by adhesives or other available means. An inner cavity 1254 is
formed by the seal 1216 and a distal portion 1256 of the resilient
reel, and defines a fluid space of the valve 1210. During
compression of the seal 1216, the spreader 1250 extends further
outwardly and pushes the central body portion 1234 of the resilient
reel 1220 outwardly. The seal 1216 and resilient reel 1220 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 the syringe 1260
partially shown in phantom in FIG. 27.
[0136] FIG. 27 illustrates compression and FIG. 26 illustrates
decompression during valve activation. In the compressed state, the
syringe 1260 is placed on the seal cap 1240 inside the opening 1226
of the housing 1212 and the application of pressure on the syringe
1260 creates pressure on the seal cap 1240. The downward pressure
pushes the seal cap 1240 away from the circular opening 1226 and
toward the lower portion of the housing 1212 which has a larger
inner diameter, thereby allowing the precut slit 1242 to open. The
ring member 1218 moves toward the support member 1214 and
compresses the resilient reel 1220. The upper flange 1232 of the
resilient reel 1220 is pushed by the ring member 1214 toward the
lower flange 1236. The central body portion 1234 bulges outwardly
as the spreader 1250 deforms and pushes the central body portion
1234 outwardly, storing potential energy of the compression. Fluid
is able to flow into the syringe 1260, or vice versa, depending on
whether fluid is to be withdrawn from the patient or medication
injected into the patient.
[0137] The compression of the seal 1216 and deformation of the
spreader 1250 and reel 1220 shown in FIG. 27 causes an increase in
volume of the inner cavity 1254 because of the expansion of the
central body portion 1234 of the flexible reel 1220. The expansion
results from the movement of the spreaders 1250 to open up the
central body portion 1234 of the resilient reel 1220 during
compression.
[0138] FIG. 26 illustrates the valve 1210 after withdrawal of the
syringe 1260. The seal 1216 returns to its decompressed state and
essentially fills the opening 1226, and the spreader 1250 reforms
to allow the central body region 1234 of the resilient reel 1220 to
narrow. Because of the contraction of the inner cavity 1254 at the
central body portion 1234, there is a net loss in fluid space,
resulting in a positive flow from the valve 1210 through, e.g., a
catheter tip (not shown). The positive-flow valve 1210
advantageously eliminates any dead space during decompression of
the seal 1216. This is further assisted by the seal 1216 with the
slit 1242 remaining open until the very end, i.e., until the seal
cap 1240 is squeezed by the circular opening 1226 at the top of the
upper conduit 1224.
[0139] In addition, the valve 1210 can be reused because the seal
1216 can return reversibly in the decompressed state. The seal
surface 1266 is also swabbable for sterility. Other features of the
valve 1210 are discussed previously in connection with the earlier
embodiments of this invention.
Thirteenth Embodiment
[0140] A thirteenth embodiment valve 1310 in accordance with the
present invention is illustrated in FIGS. 28 and 29. The valve 1310
comprises a body or housing 1312, a support member 1314 (partially
shown), an upper seal 1316, and a lower seal 1318. The housing 1312
has an upper conduit 1322 near a proximal end with a circular
opening 1324 that is preferably adapted to receive a medical
implement such as a syringe 1326 partially shown in phantom in FIG.
40. The body 1312 has an upper side wall 1330 distal to the upper
conduit 1322 that is desirably circular in cross section with a
diameter larger than the diameter of the circular opening 1324. The
body 1312 has a lower side wall 1332 distal to the upper side wall
1330 with a diameter larger than the diameter of the upper side
wall 1330. A middle conduit 1338 is advantageously formed between
the upper side wall 1330 and lower side wall 1332. The upper side
wall 1330 is advantageously tapered from the upper conduit 1322 to
the middle conduit 1338 and the lower side wall 1332 is
advantageously tapered from the middle conduit 1338 to a distal end
1340 of the housing 1312. The middle conduit 1338 has a diameter
larger than the diameter of the upper conduit 1322 and smaller than
the diameter of the distal end 1340 of the housing 1312.
[0141] The support member 1314 has at its distal end an inner
conduit (not shown) which may be connected to a terminal of a
catheter (not shown). The support member 1314 serves as a support
and attachment device for the upper and lower seals 1316, 1318 by
holding the seals 1316, 1318 in place inside the internal cavity
1346 of the housing 1312.
[0142] The upper and lower seals 1316, 1318 are prepared from a
resilient material that is flexible, inert, and impermeable to
fluid, such as silicon. The upper seal 1316 has a seal cap 1350
with a generally flat top surface 1352, a shoulder 1354, a side
wall 1356, and a base 1358. The side wall 1356 advantageously is
comprised of ringed wall portions 1360 which deform in an
accordion-like fashion and assist in the reformation of the seal
1316 to enclose the housing opening 1324 upon withdrawal of the
syringe 1326. During compression of the upper seal 1316, the
diameter of the ringed wall portions 1360 expand outwardly in the
radial direction. The interior of the upper seal 1316 is hollow to
provide an upper inner cavity 1362, as best seen in FIG. 28. The
shoulder 1354 engages an upper ledge 1366 provided in the upper
conduit 1322 of the housing 1312 such that the upper ledge 1366
confines the movement of the shoulder 1354 toward the opening 1324
to prevent the upper seal 1316 from being blown through the opening
1324 under high pressure in the upper inner cavity 1362 of the seal
1316,
[0143] The seal cap 1350 of the upper seal 1316 reseals in the
valve 1310 at the opening 1324 with the top surface 1352 of the
seal 1316 flush with or above the opening 1324 upon removal of the
medical implement 1326. The seal cap 1350 substantially fills the
opening 1324 in the top of the upper conduit 1322. It is preferred
the top surface 1352 be exposed after assembly so that it may be
swabbed with alcohol or other disinfectant. The seal cap 1350 of
the upper seal 1316 desirably has a unique shape with a precut slit
1370 such that the seal cap 1350 is squeezed shut by the opening
1324 when assembled and the slit 1370 opens automatically during
compression. The seal 1316 desirably also includes a pressure
responsive member 1372 to further assist in creating a fluid-tight
seal in the decompressed state.
[0144] As shown in FIGS. 28 and 29, the lower seal 1318 desirably
is generally similar to the upper seal 1316. The lower seal has a
similar seal cap 1380 with a generally flat top surface 1382, a
shoulder 1384, and a side wall 1386. The side wall 1386 defines a
lower inner cavity 1390 and may include similar ringed wall
portions (not shown). The seal cap 1380 is disposed at the middle
conduit 1338 at the decompressed state and reseals the lower inner
cavity 1390 at the middle conduit 1338 upon removal of the medical
implement 1326. The lower inner cavity 1390 forms a fluid space of
the valve 1310, 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 implement
1326 and to decrease upon withdrawal of the medical implement
1326.
[0145] The seal cap 1380 advantageously provides a fluid tight
seal, having a shape and a precut slit 1394 similar to those of the
upper seal 1316. The lower seal 1318 also includes desirably a
pressure responsive member 1396 similar to the pressure responsive
member 1372 of the upper seal 1316. The components of the lower
seal 1318 are generally larger than those of the upper seal 1316
because of the geometry of the valve housing 1312.
[0146] To illustrate valve activation, FIG. 29 shows the compressed
state of the valve 1310 upon insertion of the syringe 1326. The
syringe 1326 is placed on the upper seal cap 1350 inside the
opening 1324 of the housing 1212. The application of pressure on
the syringe 1326 creates pressure on the seal cap 1330, and the
resulting downward pressure compresses the upper seal 1316. This
pushes the seal cap 1350 away from the circular opening 1324 and
toward the middle conduit 1338 at a region with a larger inner
diameter, thereby allowing the precut slit 1370 to open. The
downward movement is facilitated by the compression of the ringed
wall portions 1360 of the side wall 1356 of the upper seal 1316.
The downward force is transferred to the lower seal 1318 through
the base 1358 of the upper seal 1316 which cooperates with the seal
cap 1380 of the lower seal 1318. The application of the pressure
pushes the lower seal cap 1380 away from the middle conduit 1338
and toward the lower portion of the housing 1312 which has a larger
inner diameter, thereby allowing the precut slit 1394 to open.
Fluid is now able to flow into the syringe 1326, or vice versa,
depending on whether fluid is to be withdrawn from the patient or
medication injected into the patient. FIG. 29 shows the valve 1310
opened by insertion of the syringe 1326 into the opening 1324.
[0147] In the compressed state shown in FIG. 29, the fluid space
generally contract under pressure from the decompressed state shown
in FIG. 28. Upon removal of the syringe 1326 from the upper conduit
1322, as shown in FIG. 28, the upper and lower seals 1316,1318 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 upper inner
cavity 1362 and lower inner cavity 1390, and the closing of the
precut slit 1394 of the lower seal 1318 upon compression, a
decrease in volume results in the lower inner cavity 1390 of the
valve 1310. The decrease in the fluid space advantageously
generates a positive flow from the valve 1310 through, e.g., a
catheter tip (not shown) to eliminate dead space. Advantageously,
any dead space within the upper inner cavity 1362 is also minimized
since, as the syringe 1326 is withdrawn, the slit 1370 remains open
until the very end, i.e., until the seal cap 1350 is squeezed by
the circular opening 1324 at the top of the upper conduit 1322. The
elimination of backflash is particularly advantageous in the case
where the valve 1310 is connected through a catheter to a patient,
because it prevents the introduction of blood into the
catheter.
[0148] As the upper seals 1316 is free to move to its decompressed
state, it essentially fills the circular opening 1324. The ability
of the upper seal 1316 to return reversibly to its decompressed
state, together with the resiliency of the lower seal 1318, permits
the reuse of the valve 1310. Following disconnection, and before
reuse, the surface 1352 of the seal cap 1316 is essentially flush
with the opening 1324 of the housing 1312. Thus, this flush surface
1352 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 the surface 1352 of
the seal cap 1350.
Fourteenth Embodiment
[0149] A fourteenth embodiment of a valve 1410 of the present
invention is illustrated in FIGS. 30 and 32, and comprises a valve
body or housing 1412, a seal 1414, a piston 1416, and a spring
1418. The housing 1412 has an upper conduit 1420 near a proximal
end with a circular opening 1422 that is preferably adapted to
receive a medical implement such as a syringe 1423 partially shown
in phantom in FIG. 30. The housing 1412 has a side conduit 1424
which is connected to a fluid line such as a catheter (not shown).
Disposed in a lower chamber 1426 of the housing 1412 is the spring
1418 supporting the piston 1416 which bears against a distal end
1430 of the seal 1414 disposed in an upper chamber 1432 of the
housing 1412. The lower chamber 1426 of the housing 1412
advantageously includes an orifice 1434 for venting the air therein
to facilitate movement of the spring 1418. The upper chamber 1432
and lower chamber 1426 expand and contract according to the
movement of the piston 1416 under pressure from the seal 1414 and
the spring 1418. The housing 1412 advantageously includes a side
aperture 1438 additional fluid to be transferred to the patient
through the upper chamber 1432 and side conduit 1424 when
necessary.
[0150] The seal 1414 has seal cap 1442 with precut slit 1444, a
shoulder 1446, and a pressure responsive member 1448. The seal has
a side wall 1450 which defines an inner cavity 1452 and has the
distal end 1430 that cooperates with the piston 1416 for efficient
transfer of pressure between them. Near the distal end 1430 of the
seal 1414 is desirably a transverse fluid passage 1456 for fluid
communication between the seal 1414 and the upper chamber 1432.
Although FIGS. 30 and 32 illustrate that the transverse fluid
passage 1456 also facilitates fluid flow between the side aperture
1438 and the side conduit 1424, it need not do so if fluid can flow
around the seal 1414 in the upper chamber 1432. The upper chamber
1432 and the inner cavity 1450 of the seal 1414 forms the fluid
space of the valve 1410.
[0151] FIG. 31 illustrates compression and FIG. 30 illustrated
decompression during valve activation. In the compressed state, the
syringe 1423 is placed on the seal cap 1442 inside the opening 1422
of the housing 1412 and the application of pressure on the syringe
1423 creates pressure on the seal cap 1442. The downward pressure
pushes the seal cap 1442 away from the circular opening 1422 and
toward the lower portion of the housing 1412 which has a larger
inner diameter, thereby allowing the precut slit 1444 to open. The
side wall 1450 moves further into the upper chamber 1432 and pushes
the piston 1476 downward against the spring 1418, which is
compressed, storing potential energy of the compression. Fluid is
able to flow into the syringe 1423, or vice versa, depending on
whether fluid is to be withdrawn from the patient or medication
injected into the patient. The compression of the seal 1414 shown
in FIG. 42 generates a net gain or increase in volume of the fluid
space of the valve 1410.
[0152] FIG. 30 illustrates the valve 1410 after withdrawal of the
syringe 1423. The seal 1414 returns to its decompressed state and
essentially fills the opening 1422, and the piston 1416 moves back
to its decompressed position as the spring 1418 releases its
potential energy. Because of the contraction of the upper chamber
1432 of the housing 1412, there is a net loss in fluid space,
resulting in a positive flow from the valve 1410 through, e.g., a
catheter tip (not shown). The positive-flow valve 1410
advantageously eliminates any dead space during decompression of
the seal 1414. This is further assisted by the seal 141 with the
slit 1444 remaining open until the very end, i.e., until the seal
cap 1442 is squeezed by the circular opening 1422 at the top of the
upper conduit 1420.
[0153] In addition, the valve 1410 can be reused because the seal
1414 can return reversibly in the decompressed state. The seal
surface 1460 is also swabbable for sterility. Other features of the
valve 1410 are discussed previously in connection with the earlier
embodiments of this invention.
Additional Embodiments
[0154] 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.
[0155] In addition, many of the ringed side wall of the seals (such
as the portions 1360 of the seal 1316 of FIG. 28) can be replaced
by circular tires 1580 stacked in series one on top of an adjacent
larger-diameter lower tire, as illustrated in FIG. 32. The circular
tires 1580 are preferably solid throughout the diameter of the
cross-section thereof. Like the ringed side wall portions 1360,
these circular tires 1580 will deform and reform upon,
respectively, compression and decompression of the seal.
CONCLUSION
[0156] 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.
[0157] 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.
* * * * *