BLOOD SAMPLE SEGMENT EVACUATION TOOL
FIELD OF THE INVENTION
This invention relates to personal safety in the medical laboratory, especially to the releasing of blood products from blood sample segments more efficiently, and in a way to minimize employee exposure to blood borne pathogens and disease.
BACKGROUND—DESCRIPTION OF PRIOR ART
When a patient is deficient in a blood product, such as red blood cells, platelets, or blood clotting factors, the doctor may order the patient to receive a transfusion from a donor source. In the laboratory, tests must be performed to ensure the donor blood products are compatible with the patient's blood type, preventing the possibility of a transfusion reaction.
The compatibility testing requires that a sample of the red blood cells found in the donor unit of blood be removed without compromising the units integrity. This is accomplished with the use of blood sample segments. Blood sample segments are produced by heat sealing the inch plastic tubing that attaches the needle in the donors arm to the donor bag, in about two and a half inch segments. Each segment is full of blood, just like the blood to be given to the patient. The segments are folded together and bound with a rubber band, while still attached to the donor bag. This allows a blood sample to be removed for testing, one at a time, as needed.
Heretofore the blood products were removed from the blood sample segments by cutting off one end with scissors, inserting the cut end into a clean test tube then cutting off the remaining end, allowing the blood to drain out by the force of gravity.
This process frequently sprayed tiny droplets of blood into the air with the first cut of the scissors and always left blood on and between the blades of the scissors. The scissors must be wiped off before being used on another segment, and subsequently rinsed with bleach water before being put away.
The most recent art work found with regard to blood sample segment evacuation was a device called Safety Segment Slitter, a patent pending product being sold by the Innovative Laboratory Acuylics, Inc. This device is a single piece of stainless steel, cut and shaped in a way that allows it to set in a test tube, with a sharp pointed blade cut out of one edge and bent so the point of the blade is centered in the device. As the segment is pushed down into the device it is sliced by the blade, allowing the blood to drain out over the blade and bottom plate into the test tube. The device does by-pass the use of scissors, but still allows undue exposure to blood borne pathogens in that the bottom plate and some of the sharp edges of the cut steel are covered with blood when the device is removed for disposal.
The previously patented art work with regard to the releasing of blood from blood sample segments found to date are:
1) "Blood sample processor" patent number 4,320,787 by McMorrow.
2) "Blood sample processor" patent number 4,178,451 by McMorrow.
3) "Blood sample segment detaching and tearing device" patent number 4,790,842 by Coburn.
It has been found these devices, although meritorious, are not practical in a blood bank with respect to cost and ease of use when compared to the standard use of scissors. Patents one and three above also have sharp surfaces exposed to the worker.
The present invention, using a prototype in a real blood bank setting, has proven time and again to be faster, safer and easier to use than scissors. In addition, advantageously it can be mass produced at a reasonable cost, thereby giving the laboratory a much needed product at a very reasonable price.
Hospital regulating agencies are getting more and more thorough in regards to employee safety in response to the ever increasing cases of blood borne related diseases occurring every day, including Hepatitis and, of course, AIDS.
SUMMARY OF THE INVENTION
One object of the present invention is to provide an improved blood sample segment evacuation tool.
A further object of the present invention is to provide a device for dispensing blood from a blood sample in segment characterized in that the device comprises: an elongated cylindrical tube having an open end for receiving the blood sample segment and having a closed end, an elongated hollow shaft housed within the cylindrical tube and secured thereto near the closed end, the shaft having an inside bore forming a passageway from within the cylindrical tube, through the closed end, the elongated hollow shaft having a shank with a diameter and an angled upper edge formed to pierce a wall of the blood sample segment as the cylindrical tube guides the blood sample segment onto the shaft, the passageway delivering blood from within the blood sample segment, through the closed end of the elongated cylinder.
INDUSTRIAL APPLICABILITY
To provide a tool for the blood bank employee which allows a safe means of releasing the blood sample from a blood sample segment without the fear of air borne blood droplets, the exposure to sharp, contaminated equipment or the clean up of blood equipment, thereby improving work conditions and allowing peace of mind by elimination of undue exposure to blood borne pathogens.
The use of this invention also allows a faster and more efficient means of retrieving blood samples from blood sample segments, cutting the release time by one third over scissors and in a way that virtually eliminates any accidental exposure to blood or sharp edges.
Further objects and advantages of the invention will be obvious from a consideration of the ensuing description and the accompanying drawing.
BRIEF DESCRIPTION OF THE DRAWINGS
Fig. 1 shows a perspective elevational view of a one-piece tool according to one embodiment of the invention;
Fig. 2 shows a top view of such tool taken along the line 2—2 of Fig. 1; and
Fig. 3 shows a level side view of such tool positioned to be inserted into a clean test tube with a blood sample segment positioned to be inserted into such tool.
DESCRIPTION OF PREFERRED EMBODIMENTS
Fig. 1 shows a single-piece tool according to the preferred embodiment of the invention. The tool is comprised of a hollow needle 14 approximately 5/8 inch long which is sharpened at the free end by a single angled cut across the shank producing a bevelled edge 18. The needle 14 is connected to the well 32, extending through the bottom, with the blunt end of the needle 19 stopping flush with the outside edge of the well 32.
The protective outer portion of the tool is a single tubular piece of formed plastic with a needle attachment 16 which is located in the center of the well 32. The attachment of the needle 14 to the base of the well 32 can be accomplished by: a) forced plastic injection molding of the outer shell around the needle base 18 with the needle 14 in place within the mold prior to injection or, b) by the use of an adhesive to hold needle 14 into a pre¬ formed hole at the base of well 32. The walls of the well 32 are parallel with the needle 14 and become the tube guide 12 measuring approximately 5/18 of an inch wide and approximately 1 inch long. The tube guide 12 tapers out to make the funnelled edge 10 which joins with the lip 8 at the top.
The single-piece tool of Fig. 1 is designed to facilitate a safer and more efficient means to release the contents of blood sample tubing for testing within a blood bank laboratory including
quality control and compatibility testing.
Fig. 3 shows a perspective elevational view of the invention in use, where the user sets the tool in the opening of a clean test tube 28 so that the tube guide 12 is inside the test tube 26 with the funnel edge 10 resting in the opening of the test tube 28. The funnel edge 10 is tapered in a way to accommodate a variety of the test tube sizes.
The blood sample segment 20 is inserted past the funnel edge 10 and directed by the tube guide 12 so that the needle 14 pierces the bottom edge of the blood sample segment 20 in the center. The blood sample segment 20 is pushed all the way down until its end is sitting at the bottom of the well 32, ensuring the bevel of the needle 18 has completely entered into the blood sample segment 20.
The blood inside the blood sample segment 20 usually separates with the clear yellowish plasma 22 on top and the red blood cells 24 on the bottom. Because the user needs a sample of the donor red blood cells to check for compatibility with the recipient blood, it is necessary to insert the blood sample segment 20 with the plasma end 22 sticking up out of the tool, giving the user a concentrated sample of red blood cells when the tool is activated. If the plasma 22 and the red blood cells 24 are mixed or if the blood sample segment holds only one product, such as fresh frozen plasma, then either end may be inserted.
Once the blood sample segment 20 is in place with the needle 14 penetrating the end of the blood sample segment 20, the user applies gentle pressure to the portion of the blood sample segment 20 protruding out of the top of the tool. Under gentle pressure, the blood product at the bevel edge of the needle 18 will be forced through the needle 14, exiting a drop at a time from the blunt end of the needle 19 into the bottom of the test tube 24.
Once the desired amount of blood product has been released, the tool and the blood sample segment 20 can be disposed of as one unit without fear of continued draining of blood products or
exposure to sharp edges. With the tools design, no blood can escape out of the needle 14 if pressure is not being applied, because of the vacuum that forms inside the blood sample segment 20 once the user releases pressure.
While the above description contains many specificities, the reader should not construe these as limitations on the scope of the invention, but merely an example of the preferred embodiments thereof. Artisans with an imagination will easily be able to change the dimensions and shapes of the various embodiments. For example, the funnelled opening could be stair shaped for the different test tube sizes, or omitted completely so the guide section joins directly with an over-sized lip at the top. The tube guide section could be made longer or shorter, and could be made oval shaped or even square. The hollow needle could be made of different lengths, or have a variety of bore sizes. It may be possible to make the needle out of plastic as one unit with the outer casing. Accordingly, the reader is requested to determine the scope of the invention by the appended claims and their legal equivalents, and not by the examples which have been given.