FIELD OF THE INVENTION
The invention generally relates to fluid administration or infusion devices. More
particularly, the invention relates to a fluid administration medical 5 device comprising a
hub arranged at a proximal end of a catheter tube and having an inner surface
defining a housing; a needle having a needle tip and extending through the housing
and the catheter tube when in a ready position; and a needle guard slidably arranged
on the needle and received in the housing when the needle is in its ready position,
10 wherein the needle guard is configured to guard the needle tip upon withdrawal of the
needle from the hub.
BACKGROUND OF THE INVENTION
15 A fluid administration medical device of this kind is generally known and may be used
for infusion as well as transfusion purposes. Such fluid administration medical devices
generally include a catheter hub carrying a catheter and a removable needle cannula
extending through the catheter and past the distal tip of the catheter for inserting the
needle and catheter through the skin and into a vein of a patient. Once the
20 venipuncture is successfully performed, the needle is removed and a source of
infusion liquid, such as glucose, saline solution, blood or other fluid/liquid is
connected to the catheter hub to supply the infusion fluid to the vein of the patient.
Healthcare workers are increasingly at risk of disease transmission, and nurses
25 perform the majority of invasive hypodermic procedures, such as injecting medicine,
collecting blood and inserting indwelling intravenous (I.V.) catheters. Nurses and
other healthcare personnel are routinely injured by the exposed, sharp lancet of the
needle after use on a patient. The critical time where a percutaneous injury can occur
is from the moment the needle is withdrawn from the patient, or I.V. port, to the time
30 the contaminated needle is safely discarded.
Performing the above steps without introducing air into the system is relatively
tedious, and generally results in blood escaping from the device and soiling clothing
or the like or requiring the use of absorbant materials to catch the escaping blood.
35 Also, the above connection of the infusion liquid source to the device requires
3
manipulation of parts while the catheter is in the vein of the patient, and this tends to
increase patient discomfort and the danger of damage to the patient.
Moreover, such devices are available without any safety features preventing needle
stick injury. Typically, needle guard serves to automatically cover the 5 needle tip after
withdrawal of the needle, for example, from a patient. Such needle guard serves to
prevent accidental pricking of, for example, a medical practitioner by the needle tip
after removal of the needle from the medical device. Thus, the needle can be safely
disposed of after use, without the danger of transmitting possible highly infectious
10 and/or deadly diseases to the medical practitioner.
It is desired to provide a fluid administration medical device with improved safety
features having a needle guard slidably arranged on the needle and received in the
hub when the needle is in its ready position, wherein the needle guard is configured
15 to guard the needle tip upon withdrawal of the needle from the hub.
Further, the devices of prior art have drawbacks including that their design also
imposes significant drag force on the needle shaft, which make them difficult and
undesirable to use and causes pain to the patient when in use. Generally, when the
20 needle is withdrawn from a patient, the needle grates or otherwise causes friction or
creates a drag as it slides through catheter, the hub or through needle guard creating
drag or a withdrawal force.
Another disadvantage of the prior art devices is not only that they are complicated or
25 assembled of a large number of parts, but also that they possess risks of not working
properly and that high manufacturing costs are involved in producing each of the
parts and in assembling them.
A further disadvantage is that extra operations are necessary to operate the device
30 which possess risk of omissions or wrongly executed operations by the operator.
Hence, there is a requirement for a low-cost medical device with a universal
application which shall prevent accidental contact of a medical professional or any
other person with the sharp tip of the needle after use of the disposable medical
4
device and thus prevent possible transmission of an infectious disease such as
hepatitis, HIV, etc.
It is also desired to provide a fluid administration medical device that significantly
decrease the withdrawal force required and friction caused 5 as a needle is withdrawn
through a hub being protected by a needle guard.
SUMMARY AND OBJECTS OF THE INVENTION
10 A primary object and advantage of the present invention is to provide a fluid
administration medical device with improved safety features wherein the above
disadvantages are substantially obviated.
Another object of the present invention is to provide a fluid administration medical
15 device with safety features having a needle guard slidably arranged on the needle
and received in the housing when the needle is in its ready position, wherein the
needle guard is configured to guard the needle tip upon withdrawal of the needle from
the hub.
20 Another object of the present invention is to provide an improved fluid administration
medical device that significantly decrease the withdrawal force required and friction
caused as a needle is withdrawn through a hub being protected by a needle guard.
Yet another object of the present invention is to provide an improved fluid
25 administration medical device which is inexpensive to manufacture, efficient, effective
and simple in its construction and use.
Accordingly, the present invention relates to a fluid administration medical device
comprising: a catheter tube; a hub having a distal section and a proximal section,
30 wherein the distal section is joined to the catheter tube and the proximal section
defines a housing; a needle extending through the hub and the catheter tube and
defining an axial direction, wherein the needle has opposite proximal and distal ends,
the distal end forming a needle tip; a needle hub attached to the proximal end of the
needle; a needle guard slidably arranged on the needle, wherein the needle guard is
5
movably retained in the housing of the hub when the needle extends through the hub
and the catheter tube, and wherein the needle guard is removable from the hub once
the needle tip is received in the needle guard upon withdrawal of the needle from the
catheter tube; and wherein the hub within which the needle guard is received in a
ready position, includes holding means for holding the needle 5 guard even under
retracting forces acting on the needle guard when the needle is retracted out of the
patient's vein. These holding means may include one or more depressions formed on
the inner circumferential surface of the hub into which one or more protrusions formed
on the first and second arm of the needle guard securely engages in the ready
10 position. For example, when the first arm is deflected and spread apart from the
second arm by the needle shaft.
The hub is also connected to ports adapted to receive infusion fluid through a fluid
passage. The ports are connected to the hub though the fluid passage by a
15 passageway. The hub is also provided with wings which in use may be adhesively
taped to the skin of the patient at the venepuncture site to maintain the device
stationery during the infusion.
In an embodiment, the hub is made of two parts i.e. first part and second part wherein
20 each of the parts having a distal end section and a proximal end section. The first part
defines the housing to receive the needle guard which is movably arranged on the
needle shaft.
The chamber may be formed by an indentation in the housing for accommodating the
25 first and second arm such that none of the arms deflected by the needle contacts an
inner surface of the chamber. Through such indentation the overall outer dimensions
of the housing and the catheter hub can be kept small, which it is still provided that
the first and second arm of the needle guard does not contact the inner wall surface
of the chamber.
30
Further, the first and second parts of the catheter hub may be joined by
complementary end portions, which preferably as such extend at an angle with regard
to the axial direction. This ensures that both parts are aligned concentrically towards
each other. Thereby, the assembly of such a catheter hub can be made easier.
6
These end portions may be stepped, which enlarges their contact area for a better
mutual interconnection. The end portions may also be slanted for a better mutual for a
better mutual interconnection.
5
The inner surface of the chamber may be parallel to the axial direction and defined
only by one of the first or second part. Preferably the inner surface of the chamber is
defined by either the distal end section of the first part or the proximal end section of
the second part. More preferably the inner surface of the chamber is defined by the
proximal end section 10 of the second part.
The apparatus according to one embodiment of the invention may be provided such
that the other one of the first or second part comprises a surface joined with the inner
surface of the one of the first or second part, which surface is inclined towards the
15 inside of the housing in a proximal direction of the catheter hub, wherein the surface
has a smaller inside diameter at its innermost end than a distance between outermost
points of the arms in their deflected state inside the chamber. Preferably, the first part
comprises the surface joined with the inner surface of the second part. Preferably, the
distal end section of the first part comprises the surface joined with the inner surface
20 of the proximal end section of the second part. Such a surface serves as a stop for
the arms in their deflected state such that they cannot be pulled out of the catheter
hub in the proximal axial direction as long as the needle deflects them outward in the
ready position of the needle guard. On the other hand, the inclination of the surface
supports that the arms are directed inwards when the needle guard is pulled out in
25 the retracted position, even if they have been plastically deformed by the needle in
their deflected state.
In yet another embodiment, the hub is provided with an opening or window in order to
provide additional space for arms of the needle guard, for example for the deflected
30 first arm in the ready position. The opening or window can be formed as a throughhole
through the circumferential wall of the hub. The opening in the circumferential
wall of the hub may also provide a holding edge acting as the holding means for
holding the needle guard within the hub in the ready position even under retracting
forces applied on the needle by the practitioner.
7
According to one embodiment of the invention, the hub within which the needle guard
is received in a ready position, includes holding means for holding the needle guard
even under retracting forces acting on the needle guard when the needle is retracted
out of the patient's vein. These holding means may include 5 one or more depressions
formed on the inner circumferential surface of the hub into which one or more
protrusions formed on the first and second arm of the needle guard securely engages
in the ready position. For example, when the first arm is deflected and spread apart
from the second arm by the needle shaft.
10
Alternatively, these holding means may include one or more protrusions formed on
the inner circumferential surface of the hub. The holding means on the inner
circumferential surface of the hub maybe also formed by a combination of a
depression and a protrusion wherein the needle guard has a corresponding
15 complimentary profile of a protrusion engaging the depression on the inner
circumferential surface of the hub and a depression engaging with the protrusion on
the inner circumferential surface of the hub.
These holding means can be arranged anywhere between the base portion and distal
20 region of the first and second arm and in an engaging arrangement with the holding
means provided in the corresponding region of the catheter hub.
Thus, the said one or more holding means maybe provided either or both inside
and/or outside of the said catheter housing for engaging and/or releasing the said
25 needle guard in the form of one or more projections and/or recesses. Likewise, the
outer surface of the needle guard may be provided with one or holding means
capable of being in a retaining and/or releasing arrangement with the catheter
housing of the IV catheter device.
30 The holding means include a first disc-like retaining protrusion provided on the first
arm and a retaining depression formed in the inner surface of the catheter hub and
adapted to receive the retaining protrusion.
8
The disc-like retaining protrusion has the benefit that it is engagement along a circular
contact surface with the corresponding retaining depression formed in the inner
surface of the catheter hub. Differing apparatuses as known from the prior art, this
provides an engagement between the needle guard and the hub along a substantial
annular portion of the retaining protrusion and the retaining 5 depression which
provides a safe and reliable engagement between the two components as long as the
needle guard is in its ready position and is to be prevented from being retracted out of
the needle hub. Even if the needle guard is rotated within the hub, this secure
engagement between the hub and the needle guard holds the needle guard safely
10 within the housing of the hub.
Because of a depression being formed in the inner surface of the hub for retaining the
needle guard in the chamber, instead of e.g. a protrusion, the hub can be
manufactured more easily and, thus, at less manufacturing cost, in particular if the
15 catheter hub is a plastic part and e.g. formed by injection molding. At the same time
the particular design of the first retaining protrusion provided on the needle guard
ensures effective engagement of the retaining protrusion with the retaining
depression and, thus, reliable retaining of the needle guard in the hub. Hence, the risk
of premature release of the needle guard from the hub during withdrawal of the
20 needle from the hub and, thus, the risk of accidental pricking by the needle is
reduced.
According to a preferred embodiment, the retaining protrusion is of part-circular, in
particular semi-circular shape. More specifically, the retaining protrusion may have
25 generally parallel proximal and distal faces and/or a convex, in particular partcylindrical,
peripheral surface.
According to another embodiment, the first retaining protrusion is arranged in the
region of a distal end of the first arm.
30
According to yet another embodiment, a second disk-like retaining protrusion is
arranged on the second arm and adapted to engage with the retaining depression as
long as the first arm is in its deflected state.
9
According to yet another embodiment, the second arm can be deflected along its
entire length radially inwards when the needle tip is received between the arms, to
thereby allow the second retaining protrusion to disengage from the retaining
depression.
5
According to yet another embodiment, the second retaining protrusion is arranged in
the region of a distal end of the second arm. In particular, the second retaining
protrusion may be arranged opposite from the first retaining protrusion.
According to yet another embodiment, the retaining depression 10 is an at least partannular
depression, preferably an annular depression.
In a further embodiment, the holding means may include at least one outer arm
formed on the base portion and adapted to engage the hub on its outer
15 circumferential surface. In particular the holding means may include two outer arms
formed on substantially diametrical locations of the base portion and adapted to
engage the hub on its outer circumferential surface. By providing such holding
means, the holding function is alternatively or additionally provided at the outside of
the hub. Thereby, the manufacturing effort can be reduced and the safety in operation
20 may be further increased.
The needle guard of the present invention includes a base portion made of a first
material and having a needle passage which extends in an axial direction from a
proximal side of the base portion through the base portion to a distal side of the base
25 portion, such that a needle having a principal outer profile can be movably arranged
in the needle passage. The needle guard further includes first and second arms
extending substantially in the axial direction from the distal side of the base portion,
with the first arm having a distal region and a proximal region. A distal wall is
transversely arranged in the distal region of the first arm. A distal wall may also be
30 transversely arranged in the distal region of the second arm.
In a further embodiment of the needle guard, a tension element surrounds the first
and second arms of the needle guard. In the deflected state of the first arm, the
tension element is expanded against a restoring force of the tension element. Once
10
the needle shaft no longer supports the distal wall of the first arm, the tension element
aids the repositioning of the first arm back into axial alignment with the axial direction.
This repositioning is necessary so that the distal wall can block the needle tip from
axially sliding out of the needle guard. In addition, the tension element helps to
enclose a space between the first and second arms and thus 5 helps to prevent the
needle shaft and the needle tip from projecting sideways out of the needle guard. In
other words, the tension element adds to the protective effect of the needle guard.
Thus, the restoring force is created by at least one of an elastic property of the first
10 arm and an additional tension element. For example, the needle guard may comprise
a tension element at least partly surrounding the arms in a region proximal of the first
retaining protrusion or – instead of surrounding the two arms – biasing the two arms
by a linear biasing action. Alternatively or additionally, the first and second arms can
be made of a resilient material having elastic properties.
15
According to yet another embodiment, the said tension element is integrally mounted
to mounting features provided on each of the arms. The mounting features may
comprise one or more mounting projections and/or mounting recesses.
20 According to yet another embodiment, the tension element is integrally mounted onto
the arms being adapted to form a partial sidewall such that together with the arms it
defines a chamber surrounding the needle in which the needle tip is held after
complete withdrawal of the needle from the medical device once the said arms snaps
together protecting the needle tip.
25
Further features of the invention provides for the said integrated resilient member or
tension element to comprise a ring like integrated form/structure partially or fully
surrounding the arms, and/or clamp, bracket, “C” clip or the like surrounding the jaws
only in part.
30
According to yet another embodiment, the needle comprises an engagement means
provided at a distance from the needle tip for engaging with the needle guard and
preventing the needle guard from sliding off the needle. Preferably, the engagement
means is formed of by enlargement of the radial dimension of the needle in at least
11
one direction as compared with a principal profile of the needle. The engagement
means can be found by a local crimp, a shoulder, a bulge formed as an annular
widening etc.
According to yet another embodiment, the needle comprises 5 at least one lateral
opening covered by the tubular catheter. The at least one lateral opening provides
communication between a lumen of the needle and an interior of the tubular catheter.
In the event of first venipuncture blood entering the lumen of the needle can exit the
needle through the lateral opening and thus become visible for the person handling.
10 The at least one lateral opening is preferably large enough in order to provide an
early blood flashback function within the tubular catheter such that the practitioner
can recognize that he has placed the needle correctly within a patient's vein. In case
of a correct positioning of the needle, blood pours out of the opening within the needle
shaft into the space between the needle shaft and the inner wall of the transparent
15 tubular catheter and is visible to the practitioner. Preferably, the at least one lateral
opening is positioned close to the needle tip so that the blood does not have to travel
the length of the needle to enter the needle hub in order to become visible. Instead,
blood entering the lumen of the needle upon venipuncture partly exits the needle
again near the needle tip, thereby becoming particularly quickly and, thus, allowing for
20 particularly fast venipuncture confirmation. The lateral opening has a size which does
not obstruct the arms of the needle guard.
In a further embodiment of the needle guard, a recess is provided in the proximal
region of the first arm of the needle guard. This recess increases the deflectability of
25 the first arm in the region it is provided and thereby reduces the restoring force acting
on the distal wall while this is being supported by the needle shaft. This allows the
needle shaft to be moved more easily relative to the distal wall, as the frictional force
acting on the needle shaft is reduced. In an alternative embodiment, the said recess
can be provided in both first and second arms.
30
In a further embodiment of the needle guard, a groove is provided in a side of the
distal wall, with the groove extending substantially in the axial direction. The groove
acts as a guide groove for the needle shaft and aids the axial movement of the needle
shaft relative to the needle guard. Moreover, the needle shaft is prevented from
12
sliding sideways off the distal wall. Such a sideways movement would significantly
increase the force required to move the needle shaft relative to the needle guard,
which would prevent a correct functioning of the needle guard. In an alternative,
embodiment, such a groove is provided in both first and second arms.
5
The needle guard may also include a stopping element which is arranged in the
needle guard. The stopping element is made of a second material different from the
first material and has a through-bore with a profile which is adapted to the principal
outer profile of the needle shaft. In the case of e.g. circular cross-sections, a diameter
of the through-bore can be slightly larger than a principal outer 10 diameter of the
needle. The stopping element, preferably, may be formed by a washer integrally
formed within the base portion.
In order to allow a trouble free movement of the needle relative to the needle guard
15 when the needle is withdrawn from the catheter tube, the stopping element is
preferably arranged such that its through-bore is in general alignment with the needle
passage of the needle guard.
The stopping element can be arranged anywhere between the base portion and distal
20 region of the first and second arm. For example, the stopping element may be
arranged within the base portion. Also formed from a different material, it can be
integrated therein. As a preferred alternative, the stopping element may be arranged
loosely on the needle between the two arms of the needle guard and floating on the
needle shaft. In this embodiment, the stopping element may be formed by a tube-like
25 element. It can be held by holding means, like a recess or protuberances in a
predetermined section of the needle guard. Because of the movability of the stopping
element relative to both the needle and the base portion, the force that has to be
applied for pulling the needle through the needle guard upon withdrawal of the needle
is reduced.
30
The stopping element can be a circular disk, a ring, or a washer. However, it need not
necessarily be circular and can have any other geometric shape such as a
rectangular square or triangular shape.
13
Preferably, the second material is of greater hardness and/or stiffness than the first
material. For example, the first material could be a plastic material and the second
material could consist of a metal, a ceramic or a rubber material, or any other type of
material which is stiff and not as easily distorted as the first material.
5
According to an embodiment, the stopping element completely surrounds the needle.
The length of the stopping element, i.e. its dimension seen in the axial direction, may
vary. As such, the stopping element can, for example, be a disk, a ring, or a tube.
According to an alternative embodiment, it is also possible that the stopping element
only partly surrounds the needle. In this case, the stopping element 10 could have the
shape of a slotted disk, ring, or tube. Furthermore, it has to be understood that outer
profile of the stopping element does not have to have a circular outer profile. It is also
possible that the outer profile of the stopping element is of non-circular form, for
example, of oval or polygonal shape.
15
According to an embodiment, the stopping element is arranged in the base portion.
For example, the stopping element can be arranged in a cavity or cut out provided in
the base portion. Alternatively, the stopping element can be arranged between the
first and second arms.
20
The invention also provides a fluid administration medical device including a needle
guard in accordance with the present invention. The medical device further including
a catheter tube, a hub and a needle having a needle shaft, a needle tip and a needle
hub, wherein the needle shaft has a distal section and a proximal section, with at
25 least the proximal section having a principal outer profile.
The needle also may have an enlargement provided between the distal section and
the proximal section of the needle shaft. The enlargement has an outer profile one
dimension of which is larger than a maximum dimension of the profile of the through
30 bore of the stopping element. In a preferred embodiment, the enlargement is made by
a crimping of the needle shaft. However, other ways of forming the enlargement are
possible, such as applying additional material to the needle shaft, e.g. by soldering,
welding or gluing etc.
14
The inner profile of the needle can either be reduced in the region of the enlargement,
for example, if the enlargement is formed by crimping, or it can be substantially
constant throughout the length of the needle, for example, if the enlargement is
formed by applying additional material to the needle shaft.
5
The needle may also be formed with an opening arranged distally or proximally from
the enlargement. This opening may be formed by a small slit which is cut into the
needle shaft and which extends in axial direction for about a small distance. The
opening is just large enough in order to provide an early blood flashback function
close to the needle tip within the catheter tube such that 10 the practitioner can
recognize that he has placed the needle correctly within a patient's vein. In case of a
correct positioning of the needle, blood pours out of the opening within the needle
shaft into the space between the needle shaft and the inner wall of the transparent
catheter tube and is visible to the practitioner.
15
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS:
The foregoing and other objects, features, and advantages of the invention will be
apparent from the following detailed description taken in conjunction with the
20 accompanying drawings, wherein:
Fig. 1 is a side view of the fluid administration medical device according to the
present invention.
25 Fig. 2 is a cross-sectional view of hub of the fluid administration medical
device according to the present invention.
Figs. 3A and 3B illustrate hub of the medical device according another
embodiment of the invention.
Figs. 4A and 4B illustrate hub of the medical device according to yet another
30 embodiment of the invention.
Fig. 5A-5C are different embodiments of needles.
15
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the presently disclosed invention will now be described in detail with
reference to the drawings wherein like reference numerals designate identical or
corresponding elements. In the drawings and in the description, 5 the term “proximal”
refers to a region of the device or parts thereof or a location on the device which is
closest to, for example, a user using the device. In contrast to this, the term “distal”
refers to a region of the device which is farthest from the user, for example, the distal
region of a needle will be the region of a needle containing the needle tip which is to
10 be inserted e.g. into a patient's vein.
Referring to Fig. 1 a fluid administration medical device 10 having one or more ports
58 in accordance with the present invention is illustrated. The medical device 10
includes a hub 12, a catheter tube 14, a needle 20, wings 60, ports 58 and fluid
15 passage 62. The hub 12 is also connected with ports 58 adapted to receive infusion
fluid through a fluid passage 62. The ports 58 are connected to the hub 12 though the
fluid passage by a passageway 72. The hub 12 is also provided with wings 60 which
in use may be adhesively taped to the skin of the patient at the venepuncture site to
maintain the device stationery during the infusion.
20
As shown in Figs. 2, 3B and 4B, the hub 12 has a distal end 22 and a proximal end
24, the catheter tube 14 is arranged adjacent to the distal end 22 of the hub 12. The
needle 20 has a needle shaft 28, a needle tip 30 at a distal section 34 of the needle
shaft 28 and a needle hub 16 attached to a proximal end 36 of the needle shaft 28.
25 An enlargement 32 of the needle 20 is provided between the distal section 34 and
the proximal section 36 of the needle shaft 28. The enlargement 32 has a maximum
dimension in a direction transverse to the needle shaft 28, which is greater than the
outer diameter of the distal and proximal sections 34, 36. The enlargement 32 can be
made, for example, by crimping the needle shaft 28.
30
In order to retain the needle guard 26 in the hub 12 while the needle 20 is being
withdrawn from the catheter tube 14, the protrusions 64 provided on both the first arm
40 and the second arm 42 of the needle guard 26 engage with depressions 66 or
protrusions 64 or combinations thereof provided on the inner circumferential surface
16
of the hub 12. The protrusions 64 may form an annular ring extending along the entire
inner periphery of the hub 12, or they may form one or more ring segments extending
along only a respective part of the inner periphery of the hub 12. Similarly, the
depressions 66 may form an annular groove extending along the entire inner
periphery of the hub 12, or they may form one or more groove 5 segments extending
along only a respective part of the inner periphery of the hub 12.
Once the needle 20 has been withdrawn such that the needle tip 30 has passed the
distal wall 18 and is received between the first 40 and second 42 arms, the needle
10 shaft 28 no longer supports the distal wall 18. This causes the first arm 40 to
reposition itself in axial alignment with the needle 20 due to the restoring force acting
on the first arm 40 in its deflected state. The realignment of the first arm 40 is aided
through the inherent biasing force of the first arm 40 and additionally through the use
of the tension element 46. The realignment of the first arm 40 causes the protrusions
15 64 to disengage from the depressions 66 or protrusions 64 in the hub 12 allowing the
needle guard 26 covering the needle tip 30 to be removed from the hub 12 together
with the needle 20, with the guarded needle tip 30 being arranged in a space which is
bounded by the base portion 44, the first and second arms 40, 42, the distal wall 18
and the tension element 46.
20
Prior to use of the medical device 10, the needle 20 is received in the hub 12 and
catheter tube 14, such that the needle shaft 28 extends through the length of the
catheter tube 14. A needle guard 26 is movably arranged on the needle shaft 28 and
retained in the hub 12 prior to use of the catheter apparatus 10 as shown in Fig. 2, 3B
25 and 4B. The needle guard 26 has a base portion 44, a first arm 40, a second arm 42
and a distal wall 18. The distal wall 18 is arranged at a distal end of the first arm 40
and extends in a direction transverse to an axial direction A. A tension element 46, for
example, a rubber band or the like, surrounds the first and second arms 40, 42. The
first and second arms 40, 42 of the needle guard 26 extend generally in the axial
30 direction A from the distal side 60 of the base portion 44, i.e. generally parallel to the
needle shaft 28. The ports 58 are used for the administration of fluids to or from a
patient through fluid passage 62.
17
In one of the preferred embodiments, upon withdrawal of the needle 20 from the
catheter tube 14 and hub 12 the needle shaft 28 moves relative to the needle guard
26 until the needle tip 30 is received in the needle guard 26. Once the needle tip 30 is
received in the needle guard 26 the enlargement 32 of the needle shaft 28 engages
with the base portion 44 of the needle guard 26 via a stopping 5 element 38 such that
the needle guard 26 can be pulled out of the hub 12 together with the needle 20. An
axial movement of the needle 20 relative to the needle guard 26 is now limited, as the
distal wall 18 blocks the needle tip 30 and the engagement between the enlargement
32 and the base portion 44 via the stopping element 38 prevents the needle tip 30
10 from being removed via the base portion 44, i.e. the needle tip 30 is safely
surrounded by the needle guard 26.
The fact that the stopping element 38 is made from a second material which is harder
and less easily distorted than the first material of the base portion 44, has the effect
15 that the needle guard 26 is secured more effectively on the needle shaft 28 and can
be retained even if excessive external force is applied when pulling on the needle, as
the enlargement 32 is prevented from being pulled through the base portion 44 of the
needle guard 26 due to the stopping element 38.
20 The stopping element 38 is made of a material different to the material of the base
portion 44, in particular, a material having a greater hardness and/or stiffness than the
material of the base portion 44. Preferably, the stopping element 38 is made of metal
or ceramic, but it can be made out of any other material which is stiff and is not easily
bent.
25
The base portion 44 and first and second arms 40, 42 of the needle guard 26 can be
made from a plastic material, for example by a moulding process.
Hence, it is prevented that the needle guard 26 is removed from the needle tip
30 accidentally. As a result, the needle guard 26 provides a better protection against
accidental pricking and thus increased safety for the person handling the medical
device.
18
In one embodiment, as shown in Fig. 3B, The hub 12 is provided with a through-hole
forming a window 68 which provides sufficient space for a distal radially outer portion
70 of the first arm 40 and second arm 42 in the region of the distal wall 18 such that in
the ready position shown in figure 2B the distal portion 47 may deflect to such an
extent that it protrudes into the window 68 formed by the through-5 hole. The window
68 additionally provides a holding function in order to prevent an axial movement of
the needle guard 26.
In one embodiment, as shown in Figs. 4A and 4B the hub 12 is made of two parts i.e.
10 first part 12a and second part 12b. Both the parts 12a and 12b has a distal end
section 50 and a proximal end section 52. The first part 12a defines a housing 48 to
receive a needle guard 26 which is movably arranged on the needle shaft 28. The
distal end section 52 of the second part 12b is connected to a catheter tube 14. In
particular, as can be seen in Figs. 2A and 2B, the first and second parts 12a and 12b
15 are joined by complementary stepped end portions 74, 76. Moreover, the second part
12b comprises a surface which is inclined towards the inside of the housing 48 in a
proximal direction of the hub 12.
The distal end section 50 of the first part 12a is configured to be assembled with the
20 proximal end section 52 of the second part 12b in various ways in a fluid tight
manner, such as by adhesive sealing, ultrasonic welding, heated die, radio frequency
sealing, mechanical seal (snap fit), insert molding, laser welding etc. ensuring a leak
free joint providing a hermetic seal. It is also possible to join the two parts 12a, 12b to
one another, for example, via a quick-connect fitting, a threaded connection, by
25 interference, a snap-fit, a press-fit or a combination thereof, or by any method of
attachment known in the art.
In one embodiment, the housing 48 of the first part 12a of the hub 12 that houses the
needle guard 26 is configured such that it defines a chamber 54 at one end of the first
30 part 12a. The chamber 54 is configured to provide room/space for the needle guard
26 in its ready position. In this embodiment, the chamber 54 is arranged in the distal
end section 50 of the second part 12a. The chamber 54 is formed by an indentation in
the housing 48 for accommodating the first and second arms 40 and 42 such that
19
none of the arms 40 and 42 deflected by the needle 20 contact the inner surface 56 of
the chamber 54.
In this ready position, the first arm 40 deflects outward of the needle guard 26 such
that the distal wall 18 of the first arm 40 is supported on the needle 5 shaft 28. Further,
in this ready position, except for the holding means, the first and second arms 40, 42
do not engage or interact with the inner wall/surface 56 of the chamber 54 prior and
during venipuncture of a patient. This reduced non-contact of the first and second
arms 40, 42 with the inner wall/surface 56 of the chamber 54 significantly decreases
10 the withdrawal force required and friction caused when a needle 29 is withdrawn
through a hub 12 being protected by a needle guard 26 after use.
As shown in Fig. 2B & 3B, prior to the use of the medical device 10, the needle guard
26 is arranged in the hub near a proximal end 24 of the needle shaft 28. In this
15 situation, the needle 20 extends completely through the needle guard 26, thereby
deflecting the first arm 40 of the needle guard 26 outwards, i.e. at an angle to the
axial direction A, such that the distal wall 18 of the first arm 40 is supported on the
needle shaft 28. Following the insertion of the catheter tube 14 into a patient, the
needle 20 is withdrawn from the catheter tube 14 and the needle shaft 28 moves
20 through the needle guard 26 while the needle guard 28 is retained in the hub 12.
Once the needle tip 30 passes the transverse distal wall 18 of the needle guard 26,
i.e. such that the needle shaft 28 no longer supports the distal wall 18, a restoring
force ensures that the first arm 40 of the needle guard 26 is moved back into
alignment with the axial direction A of the needle guard 26, so that the needle tip 30 is
25 blocked by the distal wall 18 of the needle guard 26, i.e. the needle tip 30 is
prevented from axially projecting out of the needle guard 26.
The catheter apparatus 10 is particularly inexpensive to manufacture if the base
portion 44, the first and second arms 40, 42 are integrally made from a first material.
30 The first material may, for example, be a plastic material. Thus the base portion 44,
the first and second arms 40, 42 could be manufactured by injection molding.
Alternatively, the base portion 44, one of the first and second arms 40, 42 could be
integrally made from a first material, e.g. a plastic material, and the other one of the
20
first and second arms 40, 42 could be made from a second material different from
said first material. For example, said other one of the first and second arms 40, 42
could include a strip of material having spring-like properties, e.g. a strip of sheet
metal.
5
Fig. 5A shows an embodiment of a needle 20 having a needle shaft 28, a needle tip
30 and an enlargement 32 formed by a crimp. The crimp is made by a local
depression 33 such that lateral protrusions/enlargement 32 result from the crimping
process. The crimping process is controlled such that the internal cross-sectional
area of the needle is not reduced substantially such that the 10 through bore or the
internal profile of the needle is not affected.
Fig. 5B shows the needle according to Fig. 5A, however having an opening 35
arranged slightly distally from the enlargement 32, such that it is still arranged within
15 the catheter tube in the ready position. The opening 35 just extends over about 0.5
mm in axial direction and provides a through hole through the needle wall. Thereby,
an early blood flashback within the transparent catheter tube 14 can be achieved
when the needle is position into the patient's vein. Based on this blood flashback, the
practitioner can see right after puncturing the patient whether the needle has been
20 positioned correctly due to a small amount of patient’s blood flooding the space
between the needle shaft 28 and the transparent catheter tube 14.
Fig. 5C shows the needle according to Fig. 5B, however with the opening 35
arranged proximally from the enlargement 32. The opening 35 is dimensioned such
25 that it does not affect the functioning of the needle guard 26. The size of the opening
35 is such that it does not obstruct the arms of the needle guard 26. The arrangement
and/or position of the enlargement 32 and opening 35 can be interchanged. The
shape of the opening 35 may vary and include shapes such as circular, square,
rectangular, curve, oval, semi-circular or the like etc.
30
The construction and shape of the improved medical device 10 of the present
disclosure provides a simple configuration. The simple design of medical device is
advantageous in a clinical setting because it smoothen the whole catheterization
process thereby reducing injury or discomfort to patient. In addition, such design
21
greatly reduces manufacturing costs and is efficient, effective and simple in its
construction and use.
The foregoing construction and relationship of the components is believed to provide
a needle guard that has very low drag forces, such that the 5 tactile and audible
sensations thereof are acceptable to the medical practitioner, while at the same time
providing reliable protection of tip thereby minimizing risk of accidental needle sticks
therefrom.
10 Although this invention has been disclosed in the context of certain preferred
embodiments and examples, it will be understood by those skilled in the art that the
present invention extends beyond the specifically disclosed embodiments to other
alternative embodiments and/or uses of the invention and obvious modifications and
equivalents thereof. Thus, from the foregoing description, it will be apparent to one of
15 ordinary skill in the art that many changes and modifications can be made thereto
without departing from the spirit or scope of the invention as set forth in the claims.
Accordingly, it is not intended that the scope of the foregoing description be limited to
the description set forth above, but rather that such description be construed as
20 encompassing such features that reside in the present invention, including all the
features and embodiments that would be treated as equivalents thereof by those
skilled in the relevant art.
Thus, it is intended that the scope of the present invention herein disclosed should
25 not be limited by the particular disclosed embodiments described above but should be
determined only by a fair reading of the appended claims.
22
List of Reference numerals:
10 medical device
5 12 hub
12a first part of hub
12b second part of hub
14 catheter tube
16 needle hub
10 18 distal wall
20 needle
22 distal end
24 proximal end
26 needle guard
15 28 needle shaft
30 needle tip
32 enlargement
33 depression
34 distal section
20 35 opening
36 proximal section
38 stopping element
40 first arm
42 second arm
25 44 base portion
46 tension element
48 housing
50 distal end section
52 proximal end section
30 54 chamber
56 inner surface/wall
58 ports
60 wing
62 fluid passage
23
64 protrusion
66 depression
68 opening/window
70 distal radially outer portion
5 72 passageway
74 stepped surface of 12a
76 stepped surface of 12b
A Axial direction

WE CLAIM:
1. A fluid administration medical device (10) comprising:
a catheter tube (14);
a hub (12) having a distal section (34) and a proximal section 5 (36), wherein the
distal section (34) is joined to the catheter tube (14) and the proximal section (36)
defines a housing (24);
one or more ports (58) connected to the hub (12) by a fluid passage (62)
through a passageway (72);
10 a needle (20) extending through the hub (12) and the catheter tube (14) and
defining an axial direction (A), wherein the needle (20) has opposite proximal and
distal ends (22, 24), the distal end (22) forming a needle tip (30);
a needle hub (16) attached to the proximal end (24) of the needle (20);
a needle guard (26) slidably arranged on the needle (20), wherein the needle
15 guard (26) is movably retained in the housing (48) of the hub (12) when the needle
(20) extends through the hub (12) and the catheter tube (14), wherein the needle
guard (26) is removable from the hub (12) once the needle tip (30) is received in the
needle guard (26) upon withdrawal of the needle (20) from the catheter tube (14); and
wherein the housing (48) includes holding means for holding the needle guard (26)
20 against retracting forces.
2. A fluid administration medical device (10) comprising:
a catheter tube (14);
a hub (12) having a distal section (34) and a proximal section (36), wherein the
25 distal section (34) is joined to the catheter tube (14) and the proximal section (36)
defines a housing (24);
one or more ports (58) connected to the hub (12) by a fluid passage (62)
through a passageway (72);
a needle (20) extending through the hub (12) and the catheter tube (14) and
30 defining an axial direction (A), wherein the needle (20) has opposite proximal and
distal ends (22, 24), the distal end (22) forming a needle tip (30);
a needle hub (16) attached to the proximal end (24) of the needle (20);
a needle guard (26) slidably arranged on the needle (20), wherein the needle
guard (26) is movably retained in the housing (48) of the hub (12) when the needle
25
(20) extends through the hub (12) and the catheter tube (14), wherein the needle
guard (26) is removable from the hub (12) once the needle tip (30) is received in the
needle guard (26) upon withdrawal of the needle (20) from the catheter tube (14); and
wherein the hub (12) provided with an opening or window (68) providing additional
space for arms (40, 42) of the needle guard in 5 the ready position.
3. A fluid administration medical device (10) comprising:
a catheter tube (14);
a hub (12) having a distal section (34) and a proximal section (36), wherein the
10 distal section (34) is joined to the catheter tube (14) and the proximal section (36)
defines a housing (24);
one or more ports (58) connected to the hub (12) by a fluid passage (62)
through a passageway (72);
a needle (20) extending through the hub (12) and the catheter tube (14) and
15 defining an axial direction (A), wherein the needle (20) has opposite proximal and
distal ends (22, 24), the distal end (22) forming a needle tip (30);
a needle hub (16) attached to the proximal end (24) of the needle (20);
a needle guard (26) slidably arranged on the needle (20), wherein the needle
guard (26) is movably retained in the housing (48) of the hub (12) when the needle
20 (20) extends through the hub (12) and the catheter tube (14), wherein the needle
guard (26) is removable from the hub (12) once the needle tip (30) is received in the
needle guard (26) upon withdrawal of the needle (20) from the catheter tube (14); and
wherein the hub (12) is made of two parts i.e. first part (12a) and second part (12b)
each of the parts (12a, 12b) having a distal end section (50) and a proximal end
25 section (52).
4. The fluid administration medical device (10) as claimed in any of the preceding
claims, wherein the holding means include one or more depressions (66) or
protrusions (64) formed on the inner circumferential surface of the hub (12) adapted
30 to engage one or more protrusions (64) or depressions (66) formed on the outer
surface of the needle guard (26).
5. The fluid administration medical device (10) as claimed in any of the preceding
claims, the hub (12) is made of two parts i.e. first part (12a) and second part (12b)
26
each of the parts (12a, 12b) having a distal end section (50) and a proximal end
section (52).
6. The fluid administration medical device (10) as claimed in any of the preceding
claims, wherein the first part (12a) defines the housing (48) to 5 receive the needle
guard (26) which is movably arranged on the needle shaft (28).
7. The fluid administration medical device (10) as claimed in any of the
preceding claims, wherein the distal end section (50) of the first part (12a) is
10 assembled with the proximal end section (52) of the second part (12b) by adhesive
sealing, ultrasonic welding, heated die, radio frequency sealing, mechanical seal
(snap fit), insert molding, laser welding etc. ensuring a leak free joint.
8. The fluid administration medical device (10) as claimed in any of the preceding
15 claims, wherein the hub (12) provided with an opening or window (68) providing
additional space for arms (40, 42) of the needle guard in the ready position.
9. The fluid administration medical device (10) as claimed in any of the preceding
claims, wherein the opening or window (68) formed as a through-hole through the
20 circumferential wall of the hub (12).
10. The fluid administration medical device (10) as claimed in any of the preceding
claims, wherein the opening or window provides a holding edge acting as the holding
means for holding the needle guard (26) within the hub (12).
25
11. The fluid administration medical device (10) as claimed in any of the preceding
claims, wherein the needle (20) is formed with an opening (35) close to the needle tip
(30), wherein the opening (35) is located within the catheter tube (14), when the
medical device (10) is in a ready position.
30
12. The fluid administration medical device (10) as claimed in claim any of the
preceding claims, wherein the opening (35) is arranged distally or proximally from the
enlargement (32) and wherein the opening (35) extends in axial direction for a
distance of 0.3 to 1mm.