CA2023845A1 - Transfusion bag segment blood collector - Google Patents

Abstract

ABSTRACT

A collection apparatus and method for samples of liquid contained within cuttable walled elongated bodies, such as blood donor unit test segments, in which a collection test tube has a cutting means integrally mounted within it. The cutting means has a cutting edge or end so oriented that longitudinal movement of the body with respect to the tube after being introduced through the open end of the tube causes piercing or cutting of the body's wall so that its liquid contents can drain into the tube for further manipulation. Blade-like cutting means fixed and flexibly mounted in the tube and also needle-like cutting means are exemplified.

Description

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TRANSFUSION BAG SEGMENT BLOOD COLLECTOR -This invention relates to an apparatus and method for collecting test samples from donor units of blood collected for transfusion purposes.
When blood is collected for transfusion from a donor to a subsequent recipient, the typical apparatus at present used comprises a plastic bag, which contains a blood anticoagulant, connected by a sterile plastic tube to a cannula inserted in the donor's appropriate vein from which it flows to the bag. Typically, an additional bag or bags are attached from the first by similar plastic tubing so that after the blood has been allowed to stand selectively or been centrifuged and the cellular components concentrated, the various components, including the supernatant plasma can be transferred from the first bag through the tubing to the other bags. The sterile linked containers, therefore, can provide either red cell concentrate, plasma or other blood components as may be required from the single donor.
After collection, the blood must be tested and transferred to the ~ -receiving hospital's blood bank. The hospital in its turn will perform tests on(the blood, mixing samples of the donor's blood with that of a recipient in a process, which is known as a compatability or cross-match testing, to ensure safe transfusion. The donor unit cannot be sampled directly for these tests, because to do so would contaminate it. To provide for samples, therefore, the initial tube connecting the first bag to the cannula, immediately at the end of the donation process, is heat sealed at intervals to provide a number of individual segments each containing donor blood. The separate segments can be detached from one another as required at the heat sealed junction to provide individual sealed segments for tests. Typically, some fifteen segments will be provided with each donor unit assembly.
Each segment is about 8 cm long, about .4 cm in diameter, and contains about .6 ml of blood. Each is identified by a number printed on the surface, which corresponds to the donor unit bag number and they detach readily from one another when pulled apart at the heat seal or when cut with scissors. For carrying out tests it is necessary that the blood within each ` 2~384~

segment be transferred to a test tube in which the blood is collected, and from which it can be taken up with a standard pipette for the necessary manipulation, if desired, after initial preparation in the tube.
Problems exist with current procedures. Typically one of the ends of the plastic segment is cut with scissors or with a nail clipper and the blood is expelled by squeezing the other end. Alternatively both ends can be cut so that the blood runs straight out. In both instances the sample is collected in a test tube. The scissors or clippers naturally become contaminated with blood which must be rinsed off with water or saline before opening another segment to avoid any cross contamination. The small piece of tubing cut off in the procedure is another difficulty, it is contaminated and it may fly off in an unpredictable direction, uncontrollable drops of blood and aerosols too may be distributed in the process. All of this is insanitary and presents a potential health hazard should the blood be infected, particularly if infected with Hepatitis B or Human Immunodeficiency Virus (HIV). The problem of infection is greatly enhanced if the technologist inadvertently receives a cut during the process or if the blood comes into contact in any way with the technologist's skin or mucous membranes.
A million units of blood are collected annually in Canada alone, each Imit is tested an average of two or three times during its forty-five ~ -day storage life, and the need for a quick, safe and disposable system or apparatus for these tests is well established.
It is an object of the present disclosure to provide an apparatus and method for the safe and uncontaminated collection of test samples of liquid from plastic segments, which is relatively inexpensive and in which all parts involved in the collection process are disposable after use.
Embodiments of the invention will now be described, reference being made to the accompanying drawings wherein:
Figure 1 illustrates a typical transfusion unit polyvinylchloride tube, which has been isolated by heat sealing into individual plastic segments each containing a blood specimen, the tube is shown attached to its bag.

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Figure 2 shows a side view, Figure 3 a side view at right angles to Figure 2, and Figure 4 a plan view of a collection tube with contained cutting means embodying the invention.
Figure 5 shows a side view of the lower part of another collection - ;~
tube similar to Figure 2 with a modified cutting means.
Figure 6 is a side view of the lower part of a further collection tube which embodies the invention with a further cutting means.
Figure 7 is a side view of the lower part of another collection tube embodying the invention with yet a further alternative cutting means.
Figure 8 shows a segment having been introduced into the tube illustrated in Figures 2 and 4 in which the action of the cutting means against the segment is taking place and shows the coliection of the blood specimen in the lower end of the tube.
Figures 9 and 10 show side views of a yet further embodiment of the invention, in which the cutting means is rockable in its mounting in the collection tube.
Figure 11 shows a side view like Figure 9 illustrating a modified rockable cutting means.
Figure 12 shows the insertion of a segment into the embodiments of Figures 9, 10 or 11 and Figure 13 shows its partial withdrawal so that the segment encounters the cutting means and is pierced and discharges its contçnts for collection in the tube.
Figure 14 shows a side view of the collection tube of Figures 2, 3, 4, S, 9, 10 or 11 with the cutting means in rest position and accommodating a typical pipette used for withdrawing a specimen from the tube for investigation.
Figure 15 shows a side view of another embodiment having a fixed downwardly directed cutting means in the form of a blade with inserted segment and Figure 16 shows a side view of another embodiment with a downwardly directed cutting means.
A typical assembly 29 of blood containing segments 30 is shown in Figure 1, each having as an identifying number that of the donor unit bag 28 -to which it is connected at one end and each containing approximately .6 ml of anticoagulated blood. Illustrated for completeness is the connecting ,~ . . ... . . .

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tube 27 to a further bag associated with the bag 28, for instance, for plasma reception from bag 28, and also shown are additional conventional connection stubs 26 for the bag 28. Each segment is best separated from the next merely by pulling apart. Although this action separates the segments, it does not open the sealed ends, separation being made possible because in the heat sealing areas the cross section of the plastic is very considerably reduced over that for the remainder of the tube and, therefore, such areas represent the "weak links" in the chain of segments. Each segment is about 8 cm long and about .4 cm in diameter.
In the specific embodiment of Figure 2, a test tube lO, typically disposable and made for instance of polystyrene and typically of either 10 or 12 mm external diameter (both sizes are currently in use in hospitals) and of length 75 mm, is prepared by locating within it at about one-third the height of the tube, a cutting means, exemplified by a small rectangular piece of material forming a blade 12, suitably a piece of razor blade, with its cutting edge 14 upwards. Preferably, the blade is of a noncorrosive stainless steel. The blade 12 is held between opposite internal walls of the tube, contacting at points 16 and 18, and preferably under slight compression as an Euler strut as shown by the arcuate shape in Figure 4. In this prototype, because the steel of which the razor blade is made creates a brittle fracture when being snapped to the required length, a rough edge is formed for engaging the inner walls of the test tube and the blade is held in position in the tube at the level at which it is placed during assembly by the spring action of the blade in tending to return to its original flat shape. Plastic is particularly valuable as the material of the collecting tube 10 in this particular embodiment in that the rough broken edge of the blade tends to bite into it more firmly than would occur if the tube were of traditional glass. As seen most clearly in Figure 4, the blade 12 is arranged across a diameter of the tube, but because the blade is slightly deflected under its inherent spring action, the space between the inside walls of the tube and the blade is greater on one side 18 than it is on the other side 20.
It should be understood that the dimensions of the test tube and the material of which it is made can be varied, dependent upon the ,i:

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particular case and the specific embodiment intended. Thus the test tube can be conventionally made of glass but in that instance it can be desirable to provide indentations or shoulders at either side of the tube for support and mounting of the blade or cutting means. Thus, as Figure 5 shows, small projections 43, 44 may be included on the side edges of the blade or cutting means 12' which fit into indentations in the tube. The pair of indentations and projections at each side edge of the blade 12' will prevent its movement or rocking in the tube so that it is held securely. Those skilled in the art will appreciate further that the cutting means may be formed integrally with the tube. For instance the cutting means can be secured in the walls of the tube by chemical or heat softening of the tube walls after its insertion so that it becomes "welded" in place when the material of the tube walls hardens. In some instances the cutting means can be fixed with adhesive. This is particularly effective if the tube is plastic though it is not limited to plastic. In others the cutting means can be moulded and formed integrally with the tube and if necessary its cutting edge sharpened after such forming. It is also envisaged within this disclosure that the cutting means may be mounted to one wall of the tube or to the bottom by fusion, embedding or adhesion and in these embodiments with its cutting edge directed toward the open end of the tube. The cutting means may be differently shaped from that of a uniformly sided blade and may also be of pin- or needle-form with its sharp end forming the cutting edge, as illustrated for cutting means 46 of Figure 6, fixed to the tube wall by adhesive or glass weld 47, or the cutting means 48 of Figure 7 fixed to the bottom of the tube by similar adhesive or weld 49.
When it is desired to remove blood from a segment for testing, it is now merely necessary to orient the tube with its open end upwards and to introduce one end of the segment into the collecting tube 10 so that it encounters and is forced against the upwardly directed cutting or piercing edge of the cutting means, (edge 14 of the razor blade, as illustrated in Figure 8 where the segment 30' is seen as having been pushed down onto the cutting edge 14). The blood escapes from the segment 30', as illustrated for the embodiment in Figure 8, as drops 32 and collects in the bottom of -the tube at 34. This procedure does not require that the tip of the end of ~' ~

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';!, . . ' ' ' ' ' ~ " ' ' ' ' ' ' ' ' 20238~5 the segment 30' be cut off and avoids any consequent health or contamination hazard. The tip remains firmly attached to and part of the segment, while the cutting means passes through the impaled wall of the segment so that the blood contents can run out. Additional squeezing of the top of the tube can be done, if necessary or desired, to assist in expelling the blood from the segment into the tube. The tube 10 in the illustration of Figure 8 then contains the blood sample for further investigation. Once the segment is empty or sufficiently so for the technologist's purposes, the segment is withdrawn from the tube and disposed of or may alternatively be left in the tube for subsequent joint disposal. The segment is held relatively firmly in position by its engagement with the cutting means so that it does not fall into the liquid specimen in the tube with possible chance of contaminating the liquid.
Figure 14 illustrates the ease with which a flexible plastic pipette 40 can have its lower end 42 inserted into the tube right to the bottom, passing by the blade 12. The center of the blade is deflected away from the center diametric line of the tube because of the spring bending of the blade within the tube so that there is ample room for the pipette to be accommodated. With reference to Figure 4, the pipette is introduced through the space 18, rather than through the space 20. Whether such deflection of the blade is necessary for proper accommodation of the pipette will depend in any particular instance on the sizes of the pipette stem and the tube diameter. In instances where the cutting means is not a blade mounted across the tube for instance in the structures of Figures 5, 6 or 7 it is important too that the cutting means not interfere with the pipette used to empty the tube as those skilled in the art will understand.
Referring now to the further embodiments of Figures 9, 10, 11, 12 and 13, the cutting means comprises a blade 66 or 66' introduced into a tube 60 or 60' similar to tube 10, but this time the blade 66,66' is formed slightly differently from the blade 12 of Figures 2 or 5. The ends of the blade 66 as shown in Figure 9 can be tapered slightly outwardly in an upward direction, so that, when inserted into the tube, the tightest fit to the tube is along the upper edge 59 of the blade, whereas the lower part is free from the edges of the tube and a rocking action of the blade with respect to . j;l~ . . . ' : .
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the tube can be effected, as illustrated by the double headed arrow 64 in Figure 10. The structure of the cutting means may also be shaped as illustrated for blade 66' in Figure 11. Here the upper edge 59' is slightly above the level of the suspension pivot projections 58 received in small recesses or indentations at either side of the tube 60'.
It will be noted that because the inside of the tube is cylindrical, the extent of rocking of the blade in either of these embodiments is limited to a fairly small arc since the bottom sides 56,57 or 56',57' of the blade in each case will encounter the tube walls when swung from the direct vertical position. The amount of rotation permitted will depend upon the transverse width of the blade along its lower edge.
Typically, the blade will be given a taper or shaped on its lower side ends so that the bottom edge is some 5~ shorter than the pivot to pivot separation. One important difference from the mounting of cutting means as shown in Figures 2, 3, 4, 5, 6 or 7, is that the cutting edge in the instances of Figure 9, 10, 11, 12 and 13 is at the lower edge 55 or 55'.
With reference now to Figure 12, a segment 30" has been introduced into the tube 60 or 60' and this time it is pushed past the blade 66,66' so that it extends below it. By then withdrawing the segment 30", which catches against the side of the blade (see Figure 13) the blade is rocked into engagement with its cutting edge 55,55' against the side of the segment. Continued pulling on the segment rotates the blade even ~ore tightly against the side of the segment, cutting into it and allowing the blood to escape to be collected in the tube. The cut tip of the segment remains attached to its body. It is found that the segment can easily be removed from the tube after it has discharged its contents, by once again pushing the segment down to release the blade and then gently withdrawing the segment possibly also after having rotated it about a vertical axis completely to free any jagged edges from the blade edge. It is then disposed of in a suitable receptacle. Alternatively the segment may be left in the tube for later disposal.
In the instance of embodiments of Figures 9, 10, 11, 12 or 13, a pipette can also be used for withdrawing the blood from the collecting tube. Where the cutting means is a blade it can also be put undPr ;;

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longitudinal thrust in the tube at the manufacturing stage and adopt a deflected shape from its rest plane similar to that illustrated in Figure 4 so that one side of the blade provides ample room for the typical conventional pipette to be inserted right down to the bottom of the collecting tube. Where a larger tube (or a small pipette) is used the deflection of the blade out of its rest plane may not be required and it need not be end loaded.
While removal of the specimen of collected blood from the tube has been described, the technologist may want to process the sample in the collecting tube directly. This can clearly be done. When the tube is no longer required it and its contained segment, if not already removed can be disposed of as a single unit.
It is also possible as illustrated in Figure 16 to construct embodiments similar to those of Figures 9 to 11 in which the cutting means comprises a blade 71 with its cutting edge 74 on its lower side but where the blade is not rockable (being mounted, for example, similarly to blade 12') and is fixed offset from the position shown in Figure 12 towards that shown in Figure 13. Because the segment 73 to be cut is flexible it can be pushed past the blade even though the clearance at the lower edge is such that the segment cannot pass without distortion from its circular cross section. When the segment is then pulled outwards of the tube the cutting edge 74 prevents its withdrawal, pierces into the side, and the contents are released.
Yet further embodiments similar to those just described and as illustrated in Figure 16 may comprise a piercing member 80 mounted by welding or adhering 82 to the tube wall as in Figure 6 but with the piercing (cutting) end 81 directed downwardly towards the bottom of the tube. In such a structure the segment is pushed into the tube so that it is adjacent the lower piercing end and when withdrawal is attempted it catches on the end and becomes pierced to discharge its contents.
It is useful that the collection tube of any of the embodiments have calibration marks to show the quantity of liquid contained.
Appropriately these would be at half millilitre separation to show at least .5, 1.0, 1.5 and 2.0 millilitres though, of course, additional marks can be - 2~2~3~

provided if considered desirable in any particular case. Such marks can be easily provided in manufacture especially for plastic collection tubes.
In all instances where the cutting means comprises a blade its cutting edge need not be straight but may for instance be saw or tooth edged to improve cutting engagement of the elongated body and the cutting means.
For all of the embodiments described even greater disposal safety can be provided by supplying each with a flexible cap that may be put over the top of the collection tube when it is ready for disposal so that the contents are all sealed within the tube and spillage, leakage or-loss of any contained pieces or debris is avoided.

PAT 1622-1 .

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Claims (15)

1. Apparatus for the collection of a sample of a liquid contained within an elongated body having a cuttable wall which comprises:
a collecting tube closed at one end and open at the other, cutting means integrally mounted within said tube and having a cutting edge thereon for engaging at least one of said walls of said elongated liquid containing body when said body is moved through said open end of said tube in a longitudinal direction with respect to said tube and longitudinal force is exerted on said body with respect to said cutting means, said cutting edge thereby entering and penetrating the wall of said body, permitting discharge of said liquid into said tube and collection therein.

2. Apparatus as defined in claim 1, said cutting edge and said elongated body being mutually releaseable by relative longitudinal movement of said tube and said body in a direction opposite to that causing said penetration.

3. Apparatus as defined in claim 1, said cutting means being fixed in said tube, the cutting edge being directed toward the open end of said tube.

4. Apparatus as defined in claim 1, the cutting means being fixed in said tube, the cutting edge being directed away from the open end of said tube.

5. Apparatus as defined in claim 3 or 4, the cutting means being of pin- or needle- form.

6. Apparatus as defined in claim 1 or 2, said cutting means comprising a blade traversing said tube, the cutting edge being formed on an upper edge of said blade.

7. Apparatus as defined in claim 1 or 2, said cutting means comprising a blade transversing said tube, said cutting edge forming a lower edge to said blade and being offset from the longitudinal direction for catching said segment between said cutting edge and said tube.

8. Apparatus as defined in claim 1 or 2, said cutting means comprising a blade traversing said tube, said cutting edge forming a lower edge to said blade and said blade being limitedly rockable about an axis spaced from its lower edge so that said lower edge rocks in a sideways direction in said tube for catching said segment between said cutting edge and said tube.

9. Apparatus as defined in claim 1 or 2, said cutting means comprising a blade traversing said tube and said blade being of length slightly greater than the width of the tube at points of suspension within the tube, said blade being deflected as an Euler strut and retained in position between said walls by springing tendency to return to undeflected shape.

10. Apparatus as defined in claim 1 or 2, said cutting means comprising a stainless steel blade.

11. Apparatus as defined in any preceding claim wherein the elongated body comprises a blood transfusion tube segment.

12. A method of collecting a sample of a liquid contained within an elongated body having a cuttable wall comprising the steps of:
preparing a collecting tube having a closed and an open end with a cutting means having a cutting edge and integrally mounted within the tube, inserting said body into said open end of said tube and into contact with said cutting edge, moving said body longitudinally of said tube relatively to said cutting means for piercing said body wall by said cutting edge, and permitting said liquid to drain into said closed end of said tube.

13. The method as defined in claim 12, the cutting means being mounted in the tube by the step selected from heat softening said tube, welding to said tube, and adhering to said tube.

14. The method of claim 12 or 13, wherein said moving step comprises moving said body in a direction longitudinally inwardly of said tube.

15. The method of claim 12 or 13, wherein said moving step comprises moving said body in a direction longitudinally outwardly of said tube.