GUIDE WIRE INTRODUCER

INTRODUCTEUR DE FIL DE GUIDAGE

English Abstract

ABSTRACT OF THE DISCLOSURE


In one of its aspects the invention provides a guide
wire introducer for use in leading a flexible guide wire into a
hollow needle positioned to lead the guide wire into a blood
vessel, the introducer comprising an elongate tubular sheath
having a wall defining a lumen, and a tip attached to the sheath
at one end of the sheath. The tip combines with the lumen to
contain the guide wire loosely for movement through the lumen
and tip. An opening is formed in the wall of the sheath to
expose the wire and the opening is proportioned to permit a user
to engage the wire with a finger to slide the wire along the
lumen.

Claims

I CLAIM:

1. A guide wire introducer for use in leading a flexible
guide wire into a hollow needle positioned to lead the guide
wire into a blood vessel, the introducer comprising:
a tubular sheath having an outer surface and extending
about a longitudinal axis, the sheath defining a longitudinally
extending lumen bordered by a platform and an inner surface
extending generally parallel to an adjacent first part of the
outer surface, a major part of the cross-sectional area of the
material of the tubular sheath being contained between the
platform and an adjacent second part of the outer surface; and
an access opening in the sheath at a location in said
first part of the outer surface to expose the platform so that
when a guide wire is inserted in the lumen, the wire rests on
the platform and is available to be moved longitudinally using a
thumb in the opening while gripping the sheath with the fingers
whereby the guide wire can be moved through the introducer,
through the needle, and into a selected position in the blood
vessel.

2. A combination of a guide wire introducer and a hollow
needle for leading a guide wire into a blood vessel, the
combination comprising:
a hollow needle for insertion into a blood vessel, the
needle having a proximal end and a sharpened distal end
a tubular sheath having an outer surface and extending
between proximal and distal ends about a longitudinal axis, the



sheath defining a longitudinally extending lumen bordered by a
platform and an inner surface extending generally parallel to an
adjacent first part of the outer surface, a major part of the
cross-sectional area of the material of the tubular sheath being
contained between the platform and an adjacent second part of
the outer surface;
an access opening defined in the sheath at a location
in said first part of the outer surface to expose the platform
so that when a guide wire is inserted in the lumen, the wire
rests on the platform and is available to be moved
longitudinally using a thumb in the opening while gripping the
sheath with the fingers; and
the needle and sheath cooperating at the respective
proximal and distal ends to define location means for
positioning the sheath with the needle so that the guide wire
will pass directly from the sheath into the needle and thence,
in use, into a blood vessel for positioning at a selected
location in the blood vessel.



3. A guide wire introducer for use in leading a flexible
guide wire into a hollow needle positioned to lead the wire into
a blood vessel, the introducer comprising:
a tubular sheath having a longitudinal axis and
defining a lumen with respect to said axis such that in
cross-section the wall of the tubular sheath is thin at a first
location and thicker at a second location diametrically spaced
from the first location;
a tip coupled to the sheath and adapted to combine with



the needle to locate the sheath as the wire is fed into the
needle;
an opening defined by the sheath in said first location
and positioned adjacent the tip and exposing the lumen to
provide access for manually moving the wire axially along the
lumen to feed the wire into the needle.



4. An introducer as claimed in claim 3 in which the lumen
is defined in part by a platform positioned at a side of the
lumen nearest said second location.



5. An introducer as claimed in claim 3 in which the tip is
tapered.



6. A guide wire introducer for use in leading a flexible
guide wire into a hollow needle positioned to lead the guide
wire into a blood vessel, the introducer comprising:
a tubular sheath having an outer surface and extending
about a longitudinal axis, the sheath defining a longitudinally
extending lumen; and
an access opening in the sheath to expose the lumen so
that when a guide wire is inserted in the lumen, the wire is
available to be moved longitudinally using a thumb while
gripping the sheath with the fingers whereby the guide wire can
be moved through the introducer, through the needle, and into a
selected position in the blood vessel.

7. A combination of a guide wire introducer and a hollow



needle for leading a guide wire into a blood vessel, the
combination comprising:
a hollow needle for insertion into a blood vessel, the
needle having a proximal end and a sharpened distal end;
a tubular sheath having an outer surface and extending
between proximal and distal ends about a longitudinal axis, the
sheath defining a longitudinally extending lumen;
an access opening defined in the sheath to expose the
lumen so that when a guide wire is inserted in the lumen, the
wire is available to be moved longitudinally using a thumb while
gripping the sheath with the fingers; and
the needle and sheath cooperating at the respective
proximal and distal ends to define location means to position
the sheath with the needle so that the guide wire will pass
directly from the sheath into the needle and thence, in use,
into a blood vessel for positioning at a selected location in
the blood vessel.



8. A guide wire introducer for use in leading a flexible
guide wire into a hollow needle positioned to lead the guide
wire into a blood vessel, the introducer comprising:
a tubular sheath having an outer surface and extending
about a longitudinal axis, the sheath defining a longitudinally
extending lumen;
a tip at an end of the sheath and having a leg
extending inside the sheath, the leg defining a platform inside
the sheath; and
an access opening in the sheath to expose the platform


so that when a guide wire is inserted in the lumen, the wire
rests on the platform and is available to be moved
longitudinally using a thumb in the opening while gripping the
sheath with the fingers, whereby the guide wire can be moved
through the introducer, through the needle, and into a selected
position in the blood vessel.

9. A combination of a guide wire introducer and a hollow
needle for leading a guide wire into a blood vessel, the
combination comprising:
a hollow needle for insertion into a blood vessel, the
needle having a proximal end and a sharpened distal end;
a tubular sheath having an outer surface and extending
between proximal and distal ends about a longitudinal axis, the
sheath defining a longitudinally extending lumen;
a tip at an end of the sheath and having a leg
extending inside the sheath, the leg defining a platform inside
the sheath; and
an access opening defined in the sheath to expose the
platform so that when a guide wire is inserted in the lumen, the
wire rests on the platform and is available to be moved
longitudinally using a thumb in the opening while gripping the
sheath with the fingers; and
the needle and tip cooperating at the respective
proximal and distal ends to define location means to position
the sheath with the needle so that the guide wire will pass
directly from the sheath into the needle and thence, in use,
into a blood vessel for positioning at a selected location in
the blood vessel.

Description

20~69~9

This invention relates to the introduction of a guide
wire used in venous catheterization, and more particularly to an
introducer for containing and advancing a J-shaped flexible
guide wire into a hollow needle and hence into a blood vessel.
In some surgical procedures an intermediate step is the
introduction of a guide wire for subsequent use in guiding a
catheter into position in a blood vessel. The procedure
normally starts by using a hollow needle to penetrate body
tissue and to make an entry into the blood vessel. A guide wire
is then engaged down the needle into the blood vessel before
withdrawing the needle and making use of the guide wire for
subsequent dilation of tissue and engagement of the catheter.
The guide wire is of course extremely flexible but in its
natural relaxed state it can have an end part which is J-shaped
to permit manipulation of the wire in the blood vessel to pass
branches and irregularities in the blood vessel. As a result it
is desirable to have some form of introducer to enter the wire
into the needle.
It is an object of the present invention to provide
such an introducer and to make it in a very simple and efficient
form to permit engaging a guide wire into a needle.
Accordingly, in one of its aspects the invention
provides a guide wire introducer for use in leading a flexible
guide wire into a hollow needle positioned to lead the guide
wire into a blood vessel, the introducer comprising an elongate
tubular sheath having a wall defining a lumen, and a tip
attached to the sheath at one end of the sheath. The tip
combines with the lumen to contain the guide wire loosely for

2056919
movement through the lumen and tip. An opening is formed in the
wall of the sheath to expose the wire and the opening is
proportioned to permit a user to engage the wire with a finger
to slide the wire along the lumen.
This and other aspects of the invention will be better
understood with reference to the drawings in which:
Fig. 1 is an isometric view, with portions broken away,
showing a preferred embodiment of introducer according to the
invention and containing a J-shaped flexible guide wire;
Fig. 2 is a sectional view on line 2-2 of Fig. 1 and
drawn to a larger scale;
Fig. 3 is a side view of a part of the introducer with
a guide wire positioned ready to be introduced into a
conventional needle; and
Fig. 4 is a side view (to a scale larger than that used
in Fig. 3) with part in section to show an alternative
embodiment of the invention.
Reference is first made to Fig. 1 which illustrates an
introducer designated generally by the numeral 20 and consisting
of an elongate main part 21 in the form of a tubular sheath and
containing a guide wire 22 having a J-shaped leading end 24.
The guide wire is a loose fit in the introducer which has a
tapered tip 26 for combining with a needle (as will be
explained), and a similar tip 27 at the other end so that the
introducer can be used from either end. The cross-section of
the introducer is interrupted by an elongate opening 28 which
permits manual manipulation of the wire in the introducer as
will be explained.

20~69~9

Reference is next made to Fig. 2 which illustrates a
cross-section of the main body of the introducer. AS can be
seen in this figure, the cross-section is circular and contains
a lumen 30 which is offset with respect to the longitudinal axis
of the circular cross-section of the introducer. In the
preferred embodiment shown in Fig. 2, the lumen is generally
D-shaped in cross-section having an interior surface including a
platform 32. The outer surface of the introducer can be
considered to be in two parts. A first part is at the top of
the cross-section as drawn in Fig. 2 and a second part at the
bottom. A wall or surface 34 of the lumen 30 is parallel to the
outer surface at the first part of the introducer and the
platform 32 is adjacent the second part.
The cross-section can also be considered in terms of
the thickness of the wall surrounding the lumen 30. As drawn in
Fig. 2 a thin part of the wall is at the top of the
cross-section and a thicker part (i.e. below the platform 32) is
diametrically opposite the thin part.
The lumen 30 is proportioned to contain the guide wire
22 loosely so that it will move with minimal friction through
the introducer. As can be seen in Fig. 2, the opening 28
provides ready access for a user to engage the wire 22 using
finger and thumb about the introducer, and to slide the wire in
the introducer along the elongate opening 28.
Reference is next made to Fig. 3 where it can be seen
in broken outline that the tip has a leg 35 engaged in the lumen
30. The leg fits snugly in the lumen and is engaged with the
platform 32.

20~6~

In use, the wire 22 would be moved into the introducer
until the J-shaped end is essentially contained within the
introducer and its tip 26 as indicated in Fig. 3. The double
ended arrow 36 illustrates the directions of movement available
to the user by manipulating the wire in the introducer. Once
the wire is in the position shown in Fig. 3, the tapered tip 26
can be engaged in a matching recess in the needle 35 (not shown
but conventional) for locating the introducer while the wire is
moved into the needle. With the introducer and needle engaged
in this manner, the user can then push the wire along the
introducer by engagement in the opening 28 and thereby move the
wire right throuyh the needle and into a blood vessel. Once the
wire is in position the introducer can be removed off the wire
and the procedure continued in conventional manner.
Returning to Fig. 2, it will be appreciated that the
opening 28 has a tendency to weaken the introducer significantly
and it is for this reason that the thicker part of the
cross-section below platform 32 is provided. This provides
sufficient rigidity to maintain the shape of the introducer
regardless of the fact that part of it has been cut away to
define the opening 28. Clearly other cross-sections could be
used to achieve the same result and these are within the scope
of the invention as claimed.
The material of the main part 21 of the introducer is
preferably polyethylene with the tips moulded to fit onto the
introducer from any suitable material such as nylon. Adhesives
are used if necessary.
The length of the introducer and its cross-sectional

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shape wiil depend on the size of the guide wire to be used and
the length of the guide wire being introduced. It is also
possible to deform the thermoplastic polyethylene of the main
part 21 to form tips instead of adding moulded tips.
Reference is next made to Fig. 4 where an alternative
embodiment of introducer is illustrated. Here a sheath 38 is
circular in cross-section both inside and outside and a tip 40
is provided having a cylindrical extension 42 engaged in the
sheath and a leg 44 extending from the extension 42. The leg
defines a platform 46 so that a section of Fig. 4 taken at a
position equivalent to section 2-2 of Fig. 1 will provide a
similar shape to that shown in Fig. 2 with the platform formed
by the leg 44.
Variations such as that shown in Fig. 4 are within the
scope of the invention as claimed.

Representative Drawing