U.S. patent number 3,604,410 [Application Number 04/759,002] was granted by the patent office on 1971-09-14 for multitube blood sampler.
Invention is credited to Gary L. Whitacre.
United States Patent |
3,604,410 |
Whitacre |
September 14, 1971 |
MULTITUBE BLOOD SAMPLER
Abstract
A multitube blood sampler of a type which uses two, three or
more evacuated sample tubes of the type which are closed by rubber
stoppers. The sampler combines a retainer which holds the sample
tubes and a head fastened onto the front of the retainer which
carries a forwardly projecting cannula and rearwardly projecting
insert needles. The insert needles, within the retainer, pierce the
rubber stoppers of the tubes. The unit is completed by a branched
passageway within the head which connects the cannula to the insert
needles so that when the cannula is inserted into the vein of a
patient and the insert needles inserted into the several tubes, all
of the tubes will be filled with a blood sample. The head carrying
the cannula and insert needles is separable from the retainer and
preferably, is provided as a throwaway unit once it has been
used.
Inventors: |
Whitacre; Gary L. (Castle Rock,
CO) |
Family
ID: |
25054004 |
Appl.
No.: |
04/759,002 |
Filed: |
September 11, 1968 |
Current U.S.
Class: |
600/575; 604/191;
600/577 |
Current CPC
Class: |
A61B
5/150389 (20130101); A61B 5/154 (20130101); A61B
5/150519 (20130101); A61B 5/150221 (20130101); A61B
5/150351 (20130101); A61B 5/155 (20130101); A61B
5/15003 (20130101); A61B 5/150732 (20130101); A61B
5/150251 (20130101); A61B 5/150259 (20130101) |
Current International
Class: |
A61B
5/155 (20060101); A61B 5/15 (20060101); A61b
005/10 (); A61m 001/00 () |
Field of
Search: |
;128/2,214,215,216,221,214.2,276 ;220/60 ;128/214.2,276 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Camp; Warner H.
Claims
I claim:
1. A blood sampler adapted to receive a plurality of sample tubes
of the type which are evacuated and have stoppers closing the ends
thereof, and comprising:
a. a retainer, which is open at the rear end thereof, to receive
said plurality of sample tubes, stopper first, at selected tube
positions within the retainer;
b. a head traversing the front end of the retainer;
c. a cannula mounted upon the forward face of the head and extended
forwardly therefrom;
d. a plurality of tubular insert needles mounted upon the rearward
face of the head, extending rearwardly therefrom, and lying within
the retainer, with a needle being located upon the head at the
approximate center of each said selected tube position for contact
with and insertion into the stopper of a tube placed in the
retainer at said selected tube position; and
e. a separate passageway within the head, independently
interconnecting the cannula with each insert needle to permit the
passage through the cannula to communicate with the passage through
each insert needle, whereby blood will flow through the cannula,
when inserted into a patient's vein, and into the plurality of
sample tubes when they are placed in the retainer with the insert
needles being inserted through the stoppers.
2. In the sampler defined in claim 1, wherein said retainer is
formed as a flat unit, substantially rectangular in plan and oval
in cross section, and being adapted to hold the tubes in a
side-by-side arrangement.
3. In the sampler defined in claim 1, wherein said head is a
separable member from the retainer member, and including further, a
means adapted to attach the head onto the retainer when the sampler
is being used.
4. In the sampler defined in claim 3, wherein the attaching means
includes a hooklike lug on one member and a transversely disposed
surface on the other member adapted to be engaged by the lug.
5. In the sampler defined in claim 3, wherein a portion of one
member laps a portion of the other member, and wherein the
attaching means includes a lug at the lapped portion of one member
and a socket at the lapped portion of the other member adapted to
receive the lug.
6. In the sampler defined in claim 5, wherein one of the members is
resilient at the lapping, interlocking portions and is thereby
adapted to flex to effect disengagement of the lug from the
socket.
7. In the sampler defined in claim 3, wherein said head includes a
hood lapping the retainer having diametrically opposed, inwardly
directed lugs, wherein said retainer includes diametrically opposed
sockets at its end adapted to be engaged by the lugs when the two
members are interconnected, and wherein said retainer includes
slits at each side of one socket of sufficient extent as to form an
elastic strip which may be flexed sufficiently as to release the
lug from the socket.
8. In the sampler defined in claim 3, wherein the head comprises a
pair of flat wafers welded together as a unitary member, including
a forward, outer wafer and a rearward, inner wafer, with the
forward wafer carrying the cannula, with the rearward wafer
carrying the insert needles and with said passageways being at the
innerface of the two wafers.
9. In the sampler defined in claim 3, wherein the underside portion
of the retainer is formed as an arched surface adapted to lie upon
a patient's arm and the cannula, mounted upon the head, is adjacent
to this undersurface.
10. In the sampler defined in claim 9, wherein the walls of the
retainer are sufficiently transparent as to view the stopper end of
a tube inserted therein, and a mark on the walls of the retainer
adapted to facilitate the partial insertion of a tube to the
aforesaid selected depth.
11. A blood sampler adapted to receive a plurality of individual
sample tubes, each of which is evacuated and is closed at its end
by a comparatively thick rubber stopper, and comprising in
combination therewith:
a. a retainer having a front end, a rear end, a flattened
undersurface adapted to lie upon the body of a patient when a blood
sample is being taken and a laterally widened socket cavity therein
which opens at the rear end to receive said plurality of sample
tubes stopper-first, in a longitudinal side-by-side array at
selected positions therein, and with the floor portions of the
socket cavity being adjacent to the flattened undersurface.
b. a head traversing the front end of the retainer;
c. a cannula having an insert section adapted to be inserted into
the vein of a patient, mounted upon, outstanding forwardly from the
forward face of the head and positioned at the approximate lateral
center of the head but being offset to the bottom edge of the head
with the insert portion being substantially parallel with and lying
closely adjacent to a plane which is generally defined by the
flattened undersurface of the retainer;
d. a plurality of tubular insert needles having a length sufficient
to penetrate the tube stoppers, with one needle for each tube,
mounted upon, outstanding rearwardly from the rearward surface of
the head, within the socket cavity and at each selected tube
position, said needles lying in spaced parallelism to the cannula
insert section and in a plane parallel with the aforesaid plane
defined by the flattened undersurface of the retainer but above
this plane and near the center of the head; and
e. a passageway means in the head communicating between each
tubular needle and the cannula whereby, when each of the plurality
of tubes is partially inserted into the retainer opening, to a
selected depth, the stopper of each tube will contact a needle and
the needles will be partially inserted into their stoppers to block
off the passageway means to prevent a flow of blood from the
cannula and through the needles whenever the cannula is inserted
into a patient's vein, but when one of the tubes is thereafter
completely inserted into the retainer opening, the needle
penetrates the stopper and the passageway means is open to the
interior of the tube to permit blood to flow thereinto.
12. In the sampler defined in claim 11, wherein
the walls of the retainer are sufficiently transparent as to view
the stopper end of a tube inserted therein; and
a mark on the walls of the retainer adapted to facilitate the
partial insertion of a tube to the aforesaid selected depth.
13. In the sampler defined in claim 11, wherein the underside
portion of the retainer is formed as an arched surface adapted to
lie upon a patient's arm and the cannula, mounted upon the head, is
adjacent to this undersurface.
Description
This invention relates to blood-sampling devices, and more
particularly to blood-sampling devices which use evacuated sample
tubes for receiving blood. The present invention provides an
improved blood sampler which holds a plurality of such evacuated
sample tubes.
The present methods of blood sampling in most hospitals and clinics
throughout the country involve the use of evacuated tubes which are
closed by soft rubber stoppers. Such a sample tube is fitted into a
cylindrical retainer having a cannula projecting from its end. The
base of the cannula includes a needle extension which lies within
the retainer. Thus, whenever the cannula is inserted into a
patient's vein and the needle extension within the retainer is
pushed into and through the stopper to break the vacuum, blood will
flow from the vein and into the tube, the flow being enhanced by
the vacuum to rapidly fill the tube. The tube is then removed from
the retainer and the stopper again seals the tube as the needle is
removed.
Should it be necessary to draw several samples of blood, the sample
tube will be removed from the retainer, but the retainer will not
be removed from the patient, and another sample tube will be
inserted into the retainer and filled in the same manner.
Additional sample tubes will be filled in the same way if
necessary. While this system is far superior to, and has
practically replaced the drawing of blood with a hypodermic
syringe, it nevertheless has certain disadvantages when more than
one sample is required. The obtaining of such blood samples in this
sequential manner is time consuming, prolonging the discomfort and
sometimes pain to the patient. Moreover, blood will often flow
through the cannula when the tubes are being changed, and this lost
blood can soil clothing and generally create a mess.
The problems created by the need for multiple blood samples can
become very serious in hospitals and special care clinics, where
two or more blood samples are required each time a patient's blood
is drawn. For example, in the Swedish Hospital in Denver, Colorado,
a check indicated that in more than 90 percent of the cases where
blood was drawn, two or more samples were required each time blood
was drawn.
It follows that there is a real and definite need for improvements
in blood sampling devices where it is necessary to draw more than
one sample, and especially for a blood sampler which can reduce the
time interval between the drawing of successive blood samples and
also eliminate the problems created by blood lost between
samples.
The present invention was conceived and developed with such a need
in view, and the invention comprises, in essence, a multitube blood
sampler having a single, outwardly projecting cannula for insertion
into a patient's vein, but a plurality of insert needles for
insertion into tube stoppers. In use, the proper number of tubes
are placed in the sampler and connected with the insert needles so
that all of the tubes may be filled either simultaneously or
sequentially without removing any from the retainer. Thus, when the
tubes are filled, the retainer is removed from the patient and the
blood drawing operation is completed.
It follows that an object of the invention is to provide a novel
and improved blood sampler for a plurality of tubes, which reduces
the blood-drawing time to a minimum whenever more than one sample
is required, and at the same time, minimizes the discomfort
experienced by the patient.
Another object of the invention is to provide a novel and improved
multitube blood sampler which avoids the necessity of leaving the
cannula in a patient's vein after a sample tube is filled and
removed, and thereby eliminates the mess which is sometimes caused
by blood loss when sample tubes are being changed.
Another object of the invention is to provide a novel and improved
multitube blood sampler which includes a simplified construction of
a cannula head for a plurality of tubes, which is adapted to be
quickly and easily fastened onto and subsequently disconnected from
the sampler, and which may be provided as a sealed, completely
sterile, low-cost, throwaway unit, once it has been used.
Another object of this invention is to provide a novel and improved
multitube blood sampler which is especially suitable for being
manufactured as either a two-tube, or three-tube unit, to cope with
most demands for blood sampling, but may also be manufactured as a
unit capable of using four or more tubes.
Other objects of the invention are to provide a novel and improved
multitube blood sampler which is neat, economical and reliable, and
which involves no special techniques and is used in substantially
the same manner as single-tube blood samplers are presently being
used.
With the foregoing and other objects in view, all of which more
fully hereinafter appear, my invention comprises certain
constructions, combinations and arrangements of parts and elements
as hereinafter described, defined in the appended claims and
illustrated in preferred embodiments in the accompanying drawings,
in which:
FIG. 1 is a perspective view showing a two-tube sampler having its
cannula in a patient's forearm for drawing blood from the
patient.
FIG. 2 is a longitudinal sectional plan view of the blood sampler
shown at FIG. 1, as taken substantially from the indicated line
2--2 at FIG. 1, and with a broken line outline indicating a base
which may be used to facilitate holding the two tubes together.
FIG. 3 is an isometric front end view of the sampler per se, but
with the cannula head being separated from the tube retainer.
FIG. 4 is an isometric rear end view of the sampler per se, but
with the cannula head being separated from the tube retainer.
FIG. 5 is a fragmentary detail view of a corner of the tube
retainer, as taken from the indicated arrow 5 at FIG. 3, but on an
enlarged scale, and with a resilient portion of the retainer being
moved as to a position to effect a release of the cannula head from
the retainer.
FIG. 6 is a bottom view of the cannula head, as taken from the
indicated arrow 6 at FIG. 3, but on an enlarged scale.
FIG. 7 is a sectional view, as taken from the indicated line 7--7
at FIG. 6.
FIG. 8 is a sectional view, as taken from the indicated line 8--8
at FIG. 6.
FIG. 9 is a sectional view, as taken from the indicated line 9--9
at FIG. 6.
FIG. 10 is a fragmentary sectional portion, as taken from the
indicated line 10--10 at FIG. 7, but on a further enlarged
scale.
FIG. 11 is a plan view of an alternate construction of a three-tube
blood sampler.
FIG. 12 is a transverse sectional view, as taken substantially from
the indicated line 12--12 at FIG. 11, and with broken lines
indicating portions hidden from view, and also the manner in which
the retainer is flexed to remove the head from the retainer.
FIG. 13 is a fragmentary sectional detail, as taken from the
indicated line 13--13 at FIG. 12, but on an enlarged scale.
FIG. 14 is an isometric view similar to FIG. 3, showing a modified
form of a two-tube retainer.
Referring more particularly to the drawing, the two-tube blood
sampler shown at FIGS. 1 to 10 is a somewhat flat, cuplike unit
which is rectangular in plan and generally oval in cross section.
It is formed as two components, including a retainer R adapted to
hold the two sample tubes T. A cannula head H, attached to one end
of the retainer, carries the cannula C and two tubular insert
needles N which lie within the retainer. To facilitate the
description of these components, the head H will be designated as
being at the forward end of the sampler and thus designated, the
cannula C extends forwardly from the front wall of this
transversely disposed head, at the longitudinal center plane of
symmetry of the unit. The cannula is also adjacent to the bottom
edge of the head, that is, the bottom or undersurface of the unit
which lies upon the patient's arm as when a sample is being taken,
as illustrated at FIG. 1.
Each sample tube T is a conventional, standardized unit formed as
an evacuated cylindrical test tube 20 closed at its mouth by a
comparatively thick, soft rubber stopper 21 which holds the vacuum
within it. The tube may contain selected reagents for specific
tests and the rubber stoppers are usually color coded when reagents
are used. These tubes are all the same size and will fit any
standard sampler. The manner in which they are used is
standardized. For example, a conventional blood-drawing operation
is initiated by inserting the insert needle within the sampler part
way into the stopper 21 and at a depth which will not break the
vacuum within the tube. After the cannula is inserted into a
patient's vein, the insert needle is pushed through the stopper to
provide communication from the vein to the interior of the tube so
that a blood flow into the tube may commence which is facilitated
by the vacuum within the tube. This basic procedure is not modified
by the present invention as will appear.
In the present invention, the flat, tube-retainer R is preferably
manufactured as a unitary member of any transparent, rigid but
resilient synthetic resin such as a selected acrylic polyethylene,
vinyl, butadiene styrene or high-impact polystyrene, or any other
type which may be manufactured at low unit cost by injection
molding or other similar process. This retainer is symmetrical from
each side of its longitudinal center plane and two longitudinally
disposed passageways 24 extend through this retainer. Each
passageway has a diameter sufficient to easily receive a standard
sampler tube T and while the passageways are illustrated as being
separated by a center wall 25, it is to be noted that a portion of
this wall may be omitted as in the manner illustrated at FIG. 14.
The sidewalls 26 of this retainer are rounded or are cylindrical in
form. The bottom surface 27 is preferably arched slightly to better
fit upon a patient's arm, and to enhance the appearance of the
unit, the top surface 28 may be crowned upwardly slightly to
compliment the arched bottom surface.
The length of this retainer R is such as to permit a sample tube to
be inserted from the rear of the retainer a little more than
halfway into a retainer passageway when the stopper 21 contacts the
end of an insert needle N and this needle is inserted into the
stopper. The retainer R is necessarily transparent to permit a
technician to watch the insertion of the stopper end of a sample
tube T into a needle N. To facilitate a proper preinsertion where
the needle end does not extend through the stopper, but only
partially into the stopper as illustrated at FIG. 2, a limit line
29 may be provided across the top of the unit, the same as is
provided in conventional single-tube retainers. Also, a finger
flange 30 is provided at each side of the rear end of the retainer
to facilitate a technician in gripping it to push tubes into place
beyond the line 29 after the cannula has been inserted into the
vein of a patient.
This retainer R is completed by a means for connecting with the
cannula head H at the forward end of the unit. In the unit
illustrated at FIGS. 2 to 5, the cannula head connector includes a
socket 31 at each sidewall 26 near the front end thereof, which is
adapted to receive mating, inturned lugs on the head as hereinafter
described. In order to permit connecting with these fixed lugs, the
sidewall at one side of the retainer is formed as a flexible strip
32 between longitudinal, spaced slits 33 at each side of the
socket. These slits extend from the forward end of the retainer and
into the body of the retainer to permit the forward end of the
strip to be flexed inwardly by finger pressure a distance
sufficient to release it from a lug, as to the position illustrated
at FIG. 5. To facilitate pushing this strip to its flexed position,
a wedged-shaped finger tab 34 may be formed upon this strip as
illustrated.
The cannula head H is essentially a flat member oriented
transversely when connected to the front end of the retainer. It
consists of two parts which are joined together as will be
hereinafter described. The parts are preferably manufactured by
injection molding a synthetic resin plastic material as rigid, but
not necessarily transparent members. The plastic selected for the
head H must also be capable of bonding to hold the metal cannula
and insert needles. Suitable materials for its manufacture will
include selected types of acrylic, butadiene styrene and
high-impact polystyrene.
This head H will correspond in shape to the end of the retainer R
and it will carry the cannula C outstanding from its forward face
35 centered and adjacent to the bottom edge 27 as heretofore
described. The two insert needles N will also outstand from the
rearward face 36 at spaced locations, at the axis position of each
passageway 24 when the head is connected to the retainer.
Other features include a passageway means within the head to
connect the tubular cannula with each of the tubular insert needles
and preferably, separate passageways 37 are formed within the head,
each independent passageway 37 extending from the cannula to an
insert needle so that the passageway through the tubular cannula
may communicate with the similar passageway through the tubular
insert needles, as hereinafter further described. The head includes
further, a rearward hood 38 which overlies and extends about each
side of the forward end of the retainer when the two members are
interconnected. Each side of this hood carries a lug 39 which
engages with a socket 31 on the corresponding side of the retainer
to lock the two members together as clearly illustrated at FIG. 2
and heretofore described. To complete the head, a stop 40 outstands
from the inner face 36 adjacent to the lug 39 which engages the
socket 31 in strip 32, the stop 40 serving to limit the distance to
which the strip 32 may be flexed when disconnecting the head from
the retainer.
To facilitate the manufacture of this head H and especially the
passageways 37 within it, the head is preferably formed as two
comparatively flat wafers, a forward, outer wafer 41 and a
rearward, inner wafer 42. These wafers join a contacting surfaces
43 and 43a and are welded together by any suitable method, such as
by standard, thermal or solvent welding procedures to form a solid,
unitary member.
The forward wafer 41 carries the hood 38 which extends rearwardly
as a socketlike member to retain the rearward wafer 42. It is also
formed with a boss 44 to securely hold the cannula C in position.
The cannula, a small-diameter metal tube, is formed with a steeply
sloped forward end 45 as a point for injection into a patient's
vein, the surface of the slope facing upwardly with respect to the
wafer for proper positioning when being inserted into a patient's
vein. The base of the cannula extends through the wafer 41 as an
inclined end 46 which projects from the contact face 43 in an
upward direction to lie within the junction of the passageways 37,
hereinafter further described. To complete this forward wafer 41, a
lug 47 may project from the forward face at each side of the boss
44 to facilitate holding a protective sheath S, shown in broken
lines at FIG. 3, which can maintain the cannula in a sterilized
condition once it has been sterilized and ready for use.
The rearward wafer 42, which lies against the forward wafer 41
within the embrace of the hood 38, is formed with the passageways
37 at its contacting surface 43a as a channel having a V-shaped
path with its apex at the bottom center of the wafer at the point
where the cannula end 46 is located. Each branch of the channel
extends outwardly and upwardly from this apex and to the base 48 of
an insert needle N which is mounted in the rearward wafer 42 to
outstand therefrom. Each insert needle N is held in position in the
wafer 42 by a boss 49 projecting from the rearward surface 36 with
the rearwardly extended end 50 being pointed to facilitate its
insertion into a stopper. The base end 48 of each needle is also
inclined and with the inclined face being directed towards the
channel as in the manner illustrated at FIG. 10.
The use of this improved sampler is manifest from the foregoing
description. A retainer R may be provided for repeated use while
the cannula head H will ordinarily be provided as a throwaway item
once it has been used, such assuring a completely sterile cannula
for each patient and eliminating the chance of contamination of
blood samples. To commence a blood-sampling operation, the head H
is attached to the retainer R by fitting the lugs 39 into the
retainer sockets 31. Two tubes T are then fitted into the retainer
with the needles N being partially inserted into the stoppers 21 as
illustrated at FIG. 2. Subsequently, the cannula of the sampler is
inserted into a patient's vein, and the tubes are then pushed into
the retainer so that the needles N project through the stoppers and
into the tube cavity to permit the blood samples to be drawn. The
operation is completed by removal of the sampler from the patient,
removal of the tubes from the sampler and finally, removal of the
head from the retainer.
The tubes may be pushed upon their needles in a sequential manner
or simultaneously, once the needles have been partially inserted
into the stoppers. Whenever, it is desirable to fill both tubes
simultaneously, the pair of tubes may be carried in a common base
51 as indicated in broken lines at FIG. 2.
FIGS. 11 to 13 show a three-tube sampler similar in construction to
the unit shown at FIGS. 1 to 10 in that it is formed with a cuplike
retainer R' having a passageway 24' sufficient to accommodate three
standard sample tubes, although the passageway 24' is illustrated
at FIG. 12 as being a single passageway rather than a plurality of
passageways as heretofore described. This retainer R' is connected
with a cannula head H' at its front end and the sampler is formed
as a rectangular unit in plan, generally oval in cross section with
the underside 27' being arched and the top side 28' being crowned,
as heretofore described. Other features of the retainer R' are also
similar. It includes rounded sidewalls 26', a limit line 29' for
restricting the depth of insertion of sample tubes prior to using
the sampler, and finger flanges 30' at the rearward end to
facilitate holding the unit when the tubes T are being pushed into
position for filling. The manner in which the cannula head H' is
attached to the retainer is modified, however, in that the retainer
has sockets 31' spaced about its front edge to receive pins 39' on
the head H' as will be described.
The head H' is also generally similar in construction to the
two-tube head heretofore described, in that it is formed of two
flat wafers 41' and 42' which are welded together when the unit is
completed. The outer wafer 41' carries the cannula C in a boss 44'
in the same manner heretofore described. The inner wafer 42'
includes three passageways 37' which extend from a bottom apex
where the cannula base is located, the three passageways, shown in
broken lines at FIG. 12, extending to three insert needle bases
48'. This unit differs from that previously described in that the
inner wafer 42' is smaller than the outer wafer and is centered
upon the outer wafer to provide a rabbeted shoulder 52 whereover
the forward end of the retainer R' is fitted as best illustrated at
FIG. 13. Lugs 39' upstand from this shoulder to fit into the
sockets 31' to hold the retainer and head together. To connect or
disconnect the head from the retainer, the rabbet edge 52 is cut
back from its contact edge with the inner surface of the retainer
as at sections 53 illustrated at FIG. 12. By squeezing the
retainer, its top will be lifted as to the position indicated in
the broken line 54 at FIG. 12, to release the lugs 39' from the
sockets 31'.
The construction illustrated at FIG. 14 is a two-tube sampler
constructed essentially the same as the unit described at FIGS. 1
to 10, excepting that a different mode for connecting the head to
the retainer is provided. In this modified unit, hooks 55 are
provided at each side 26" of the retainer R" to extend from the
front end of the retainer and sockets 56 are formed at each side of
the head H" to be engaged by the hooks to hold the head H" in
position upon the retainer.
It becomes manifest that yet other constructions may be used to
carry the cannula and the plurality of insert needles, in various
head constructions or even in partial head constructions where
portions of the head may be formed integrally with the retainer,
and yet where the construction is not significantly modified from
that disclosed herein. Therefore, while I have now described my
invention in considerable detail, it is obvious that others skilled
in the art can build and devise alternate and equivalent
constructions which are clearly within the scope of the appended
claims.
* * * * *