APPARATUS TO PROVIDE COMMUNICATION WITH THE VEINS OF A PATIENT
United States Patent 3613663
An apparatus for obtaining blood specimens from a patient which includes a needle adapted to be temporarily injected and retained in communication with a vein of a patient and a body made of a self-sealing material with a cavity or void formed therein, which is in communication with the needle.
US Patent References:
Refrigerating apparatus
Horlacher - March 1960 - 2930556
Aseptic draining and support means for flexible bags
Soto - February 1967 - 3306563
Parenteral administration unit
Shaw - April 1944 - 2346334
Intravenous attachment
Eisenstein - October 1953 - 2656835
Venoclysis apparatus
Ryan - April 1958 - 2832338
Refrigerating apparatus
Horlacher - March 1960 - 2930556
Aseptic draining and support means for flexible bags
Soto - February 1967 - 3306563
Parenteral administration unit
Shaw - April 1944 - 2346334
Intravenous attachment
Eisenstein - October 1953 - 2656835
Venoclysis apparatus
Ryan - April 1958 - 2832338
Application Number:
04/758504
Publication Date:
10/19/1971
Filing Date:
09/09/1968
View Patent Images:
Export Citation:
Primary Class:
Other Classes:
604/179, 604/93.010, 604/86
International Classes:
A61B5/15; A61M39/04; A61M39/02; A61B10/00
Field of Search:
128/2,214,350,214.2,260,1,DIG.5,215,216 267/152
US Patent References:
| 2868200 | Flash-back indicator | January 1959 | Gewecke | |
| 2955595 | Therapeutic fluid sampling means | October 1960 | Semple | |
| 3157201 | Fluid exchange valve | November 1964 | Littmann | |
| 3310051 | Surgical reservoir for implantation beneath the skin | March 1967 | Schulte | |
| 3332418 | Injection site for venoclysis apparatus | July 1967 | Brody | |
| 3378006 | Piercing device guard and connector assembly | April 1968 | Burke | |
| 3429311 | FLASHBACK INDICATOR FOR PARENTERAL LIQUID ADMINISTRATION SET | February 1969 | Wickett | |
| 3447570 | PUNCTURE PAD AND HOLDER | June 1969 | Collins |
Primary Examiner:
Gaudet, Richard A.
Assistant Examiner:
Howell, Kyle L.
Claims:
What is claimed is
1. Medical apparatus adapted for treating a patient, said apparatus comprising a body of material which is penetrable by a needle and self-sealing upon withdrawal of the needle and which has wholly defined therein a cavity surrounded by said self-sealing penetrable material whereby to afford removable communication with said cavity by means of a hollow needle to provide for supply or withdrawal of fluids between said cavity and a patient, said body having at least one generally flat surface and being dimensioned such that the distance, in a first plane extending parallel to said surface and through said cavity, from said cavity to the outside of said body is substantially greater than the distance from said cavity to the outside of said body in a second plane extending through said cavity and perpendicularly to said surface, and a plate member assembled to said surface, and plate member being formed of a material which is nonpenetrable by a needle.
2. Medical apparatus adapted for treating a patient, said apparatus comprising a body of material which is pierceable by a needle and self-sealing upon withdrawal of the needle and which has therein a cavity, whereby to afford removable communication with said cavity by means of a hollow needle to provide for supply or withdrawal of fluids between said cavity and a patient, said body being generally wafer shaped with opposed faces and being dimensioned such that the distance, in a first plane extending generally parallel to said opposed faces and through said cavity, from said cavity to the outside periphery of said body is substantially greater than the distance from said cavity to the outside of said body in a second plane extending through said cavity and perpendicular to said first plane, and plate members assembled to said body and extending along the surface of each of said opposed faces, said plate members being nonpenetrable by a needle.
3. Apparatus in accordance with claim 2 including a conduit in one of the said plate members and a hollow needle extending from said one plate member and through said body into said cavity and communicating with said conduit.
4. Apparatus in accordance with claim 3 including another conduit in one of said plate members and another hollow needle extending from said plate member having said other conduit and through said body into said cavity and communicating with said other conduit.
5. Apparatus in accordance with claim 2 wherein one of said plate members has portions extending outwardly from said body on opposite sides thereof and including openings therein adapted to permit connection of said apparatus to a support.
6. Medical apparatus adapted for treating a patient, said apparatus comprising a body of material which is penetrable by a needle and self-sealing upon withdrawal of the needle and which has wholly defined therein a cavity surrounded by said self-sealing penetrable material whereby to afford removable communication with said cavity by means of a hollow needle to provide for supply or withdrawal of fluids between said cavity and a patient, said body having dimension such that the distance, in a first plane extending through said cavity, from said cavity to the outside of said body is substantially greater than the distance from said cavity to the outside of said body in a second plane extending through said cavity and perpendicularly to said first plane, and plate members assembled to said body along opposed surfaces of said body generally parallel to said first plane, said members being formed by a material which is nonpenetrable by a needle.
7. Apparatus in accordance with claim 6 wherein said body is generally wafer shaped having first and second opposed surfaces generally parallel to said first plane.
8. Apparatus in accordance with claim 6 including a conduit in one of said plate members and a hollow needle extending from said one plate member and through said body into said cavity and communicating with said conduit.
9. Apparatus in accordance with claim 8 including another conduit in one of said plate members and another hollow needle extending from said plate member having said other conduit and through said body into said cavity and communicating with said other conduit.
10. Apparatus in accordance with claim 6 wherein one of said plate members has portions extending outwardly from said body on opposite sides thereof and including openings therein adapted to permit connection of said apparatus to a support.
11. Apparatus in accordance with claim 10 including a band member extending through at least one of said openings.
12. Apparatus in accordance with claim 6 including a resilient backing attached to one of said plate members on the side thereof remote from said body.
1. Medical apparatus adapted for treating a patient, said apparatus comprising a body of material which is penetrable by a needle and self-sealing upon withdrawal of the needle and which has wholly defined therein a cavity surrounded by said self-sealing penetrable material whereby to afford removable communication with said cavity by means of a hollow needle to provide for supply or withdrawal of fluids between said cavity and a patient, said body having at least one generally flat surface and being dimensioned such that the distance, in a first plane extending parallel to said surface and through said cavity, from said cavity to the outside of said body is substantially greater than the distance from said cavity to the outside of said body in a second plane extending through said cavity and perpendicularly to said surface, and a plate member assembled to said surface, and plate member being formed of a material which is nonpenetrable by a needle.
2. Medical apparatus adapted for treating a patient, said apparatus comprising a body of material which is pierceable by a needle and self-sealing upon withdrawal of the needle and which has therein a cavity, whereby to afford removable communication with said cavity by means of a hollow needle to provide for supply or withdrawal of fluids between said cavity and a patient, said body being generally wafer shaped with opposed faces and being dimensioned such that the distance, in a first plane extending generally parallel to said opposed faces and through said cavity, from said cavity to the outside periphery of said body is substantially greater than the distance from said cavity to the outside of said body in a second plane extending through said cavity and perpendicular to said first plane, and plate members assembled to said body and extending along the surface of each of said opposed faces, said plate members being nonpenetrable by a needle.
3. Apparatus in accordance with claim 2 including a conduit in one of the said plate members and a hollow needle extending from said one plate member and through said body into said cavity and communicating with said conduit.
4. Apparatus in accordance with claim 3 including another conduit in one of said plate members and another hollow needle extending from said plate member having said other conduit and through said body into said cavity and communicating with said other conduit.
5. Apparatus in accordance with claim 2 wherein one of said plate members has portions extending outwardly from said body on opposite sides thereof and including openings therein adapted to permit connection of said apparatus to a support.
6. Medical apparatus adapted for treating a patient, said apparatus comprising a body of material which is penetrable by a needle and self-sealing upon withdrawal of the needle and which has wholly defined therein a cavity surrounded by said self-sealing penetrable material whereby to afford removable communication with said cavity by means of a hollow needle to provide for supply or withdrawal of fluids between said cavity and a patient, said body having dimension such that the distance, in a first plane extending through said cavity, from said cavity to the outside of said body is substantially greater than the distance from said cavity to the outside of said body in a second plane extending through said cavity and perpendicularly to said first plane, and plate members assembled to said body along opposed surfaces of said body generally parallel to said first plane, said members being formed by a material which is nonpenetrable by a needle.
7. Apparatus in accordance with claim 6 wherein said body is generally wafer shaped having first and second opposed surfaces generally parallel to said first plane.
8. Apparatus in accordance with claim 6 including a conduit in one of said plate members and a hollow needle extending from said one plate member and through said body into said cavity and communicating with said conduit.
9. Apparatus in accordance with claim 8 including another conduit in one of said plate members and another hollow needle extending from said plate member having said other conduit and through said body into said cavity and communicating with said other conduit.
10. Apparatus in accordance with claim 6 wherein one of said plate members has portions extending outwardly from said body on opposite sides thereof and including openings therein adapted to permit connection of said apparatus to a support.
11. Apparatus in accordance with claim 10 including a band member extending through at least one of said openings.
12. Apparatus in accordance with claim 6 including a resilient backing attached to one of said plate members on the side thereof remote from said body.
Description:
BACKGROUND OF THE INVENTION
Obtaining specimens of blood from a patient generally requires the introduction of a needle into a vein of the patient each time a specimen is taken. Repeated injection of a needle into a patient over any extended period of time leads to considerable discomfort as well as vigorous protests by the patient. The problem of obtaining specimens in obese patients is particularly acute since the veins of the patient lie buried in the subcutaneous tissue. Repeated assaults are made on a single, tiny, movable, fragile vein in the dorsum of the hand, which after the third "stick," goes into spasm, leaving only an ecchymotic area which serves as a mocking and silent testimony. Efforts have been made to relieve this discomfort in patients undergoing intravenous injections by removing the intravenous tubing at the junction with the IV needle, inserting a syringe, withdrawing a blood specimen and replacing the tubing on the IV needle. This procedure involves a certain risk in contaminating the intravenous system and the possibility of introducing foreign elements into the blood stream, in addition to being messy.
SUMMARY OF THE INVENTION
This invention provides an apparatus for periodically injecting into or removing fluid from a patient from a point remote from the veins of the patient. More particularly the invention provides medical apparatus comprising a body of material which is pierceable by a needle and self-sealing upon withdrawal of the needle and which has therein a cavity, whereby to afford removable communication with the cavity by means of a hollow needle to provide for supply or withdrawal of fluids between the cavity and a patient. The body is dimensioned such that the distance in a first plane extending through the cavity from the cavity to the outside of the body is substantially greater than the distance from the cavity to the outside of the body in a second plane extending through the cavity and perpendicularly to the first plane. In addition, the apparatus includes a plate member which is of material nonpenetrable by a needle and which is assembled to a surface of the body.
In one embodiment, the apparatus includes a wafer or disc formed from a self-sealing material with a cavity or void in the wafer connected to an intravenous needle which is adapted to be temporarily secured in a patient. Fluid is injected or removed by merely inserting a syringe needle through the self-sealing material and into the cavity. On withdrawal of the syringe needle from the cavity, the needle puncture in the wafer will be automatically closed by the self-sealing material.
This apparatus provides the patient with complete mobility during his hospital stay since the disc of self-sealing material and the intravenous needle are secured temporarily to the patient. No tourniquet is required in using this apparatus, thus virtually eliminating the possibility of obtaining spurious results. The apparatus can also be incorporated into an intravenous feeding system by connecting the cavity in the disc to a IV port in the intravenous system. The IV port can be closed when a specimen is to be taken from the cavity without disturbing any part of the intravenous feeding system.
Elimination of repeated injections into the veins of the desperately ill will salvage or preserve the veins. This is particularly significant in patients requiring injections every 2 or 3 hours.
Other objects and advantages will become apparent from the following detailed description when read in connection with the accompanying drawing in which:
FIG. 1 is an exploded view of the disc assembly for the apparatus.
FIG. 2 is a top view of the apparatus arranged for connection to an intravenous system.
FIG. 3 is a side view in section of the apparatus shown in FIG. 2.
The apparatus of this invention provides a reservoir for injecting into or removing a fluid from a patient at a point remote from the veins of a patient. More specifically, the apparatus 8 shown includes an assembly 10 having a body 18 with a cavity or void 12 connected by means of a plastic conduit 14 made of polyethylene to an intravenous needle 16 which is adapted to be injected into and left in the vein of a patient. The cavity or void 12 is formed in the body 18 with a wall of self-sealing, nontoxic, sterilizable material such as rubber. The wall of self-sealing material must be thick enough to insure a good seal. Each time fluid is to be injected into or taken from the patient, a syringe needle 20 is injected through the wall of the body 18 into the cavity 12 and the required amount of fluid is injected or is withdrawn from the cavity 12. When the needle 20 is withdrawn from the body 18, the needle will be automatically sealed by the self-sealing material, thereby preventing contamination of the apparatus.
Means are provided for protecting the assembly 10 from damage through impact while attached to the patient. In this regard, the assembly 10 is protected by means of a cover 36 and a base 30 preferably made of a plastic material and positioned in a parallel spaced relation with the body 18 positioned between the cover 36 and base 30. Various means may be used to connect the cover 36 to the base 30 and in the disclosed embodiment a pair of pegs 38 formed integral with the cover 36 extend through apertures 40 in the body 18 and are connected to the base 30. The body 18 can be made in a variety of shapes, such as a disc, wafer or doughnut with the void 12 formed in the center of the body 18. A syringe needle 20 can be inserted into the body 18 at any point on the exposed outer periphery of the disc.
Various means may be used to provide communication with the void or cavity 12 in the body 18. In the disclosed embodiment, a pair of tubes 32 are embedded in base 30 with the ends 34 of the tubes projecting upward into the cavity 12. The other ends 35 of the tubes 32 are connected to the vein of a patient and to an intravenous system. Although various means may be employed, in the disclosed embodiment the conduit 14 is used to connect the end 35 of one of the tubes 32 to the intravenous needle 16 and a second plastic conduit 22 is used to connect the end 35 of the other needle 32 to an IV port 24. All of the connections are sealed to form a closed flow path or system between the intravenous needle 16, the cavity 12, and the IV port 24 through the conduits 14 and 22. When the apparatus is used for obtaining blood specimens only, the IV port 24 is closed by means of a plug or grommet 26. Specimens can be taken from the cavity 12 in the body 18 at substantially any position around the outer circumference of the body 18 by merely inserting the syringe needle 20 through the wall of the body 18 and into the cavity 12. Although the apparatus 8 has been described as having two tubes 32 projecting into the void 12, a single tube can be used when the apparatus is used for taking blood samples only.
Means are provided for attaching the apparatus 8 to the patient to provide mobility while the patient is confined to the hospital. This means includes means for attaching the assembly 10 to the patient and means for securing the intravenous needle 16 in the patient. The assembly attaching means includes a strap or band 45 which is passed through slots 42 provided at each end of the base 30. The band 45 can be made of a strip of tape or any elastic material which can be applied to the patient. A sponge rubber backing 50 may be provided on the base 30 to cushion the assembly when mounted on the patient. The means for securing the intravenous needle 16 to the patient after injection into a vein of the patient includes a tape or strap (not shown).
In operation, the cavity 12 and tube 14 are generally filled with a neutral solution, such as a 0.9 percent saline or any balanced electrolyte solution, by inserting a syringe needle 20 or 25 into the cavity 12 or into the grommet 26 (FIG. 2). Sufficient solution is inserted to fill the cavity 12, the conduits 14 and 22 and the intravenous needle 16 to prevent the formation of an air trap or air bubble in the apparatus 8. The intravenous needle 16 is then injected into a vein in the patient and taped into position. The assembly 10 is secured to the patient at a point remote from the intravenous needle 16 and in a position convenient for injecting a syringe needle 20 into the wafer 18 by attaching the strap or band 45 to the patient. The solution in the apparatus is withdrawn to fill the conduits 14 and 22 and the cavity 12 with blood from the patient. A specimen of blood can then be taken from the cavity 12 in the body 18 by inserting the syringe needle into the cavity 12. After the blood specimen has been removed from the cavity 12, the saline solution should be re-inserted into the cavity 12 and conduit 14 and 22 to prevent clotting in the apparatus.
This apparatus can also be used as part of an intravenous system, by removing the grommet 26 from the IV port 24 and connecting the IV port 24 to intravenous tubing (not shown). Clamps 28 are provided on the conduits 14 and 22 on either side of the assembly 10 to close off the system when required. The flow of intravenous solution through the tubes 32 and the cavity 12 will provide a self-cleaning action in the cavity 12 by means of the angular deposition of the ends 34 of the tubes 32 preventing the possibility of any blood becoming stagnant in the cavity 12.
When a specimen of blood is to be taken from the cavity 12 in the wafer 10, the IV port 24 is turned off and the syringe needle 20 inserted into the cavity 12 in the wafer. The first cubic centimeter of blood withdrawn from the cavity 12 will be a mixture of blood and the intravenous solution and should be discarded. Using the same syringe needle 20 but a different syringe, the required blood specimen is withdrawn (from 10 to 20 cc. and the syringe needle 20 then removed or withdrawn from the wafer 10. The IV port 24 is turned on again to continue the introduction of the intravenous solution. The reconnection of the system for intravenous feeding flushes out the cavity 12, thus eliminating the possibility of blood becoming stagnant in the cavity 12 before the next specimen is taken.
In a specific embodiment of the apparatus, as shown in FIG. 2, the base 30 is formed from an opaque plastic that is one-eighth inch thick, 11/2 inches wide and three-fourths inches long. The tubes 32 are 19 -gauge needles and are embedded in the plastic base. The wafer or disc 18 is 11/2 inches in diameter, three-eighths inches thick with a 1/4-inch bubble or cavity in the center. The rubber consistency should be fairly firm to insure a good seal but soft enough to permit the entry and withdrawal of syringe needles of standard sizes (19-25 gauge). The polyethylene conduit is 5 inches long on the patient's side and 2 inches long on the IV side. All of the materials must be made of inert materials that will not interfere with any of the common determinations of blood.
This apparatus can also be used under conditions requiring repeated injections of IV medication. The most common of these is the repeated injection of heparin every 4 to 6 hours. The cavity 12 and conduit 14 are first primed or charged with heparin instead of the saline solution and subsequent doses of heparin are given by piercing the wafer 18 and injecting the heparin into the cavity 12. Other uses can be made of the apparatus where repeated injection or sampling is required.
Obtaining specimens of blood from a patient generally requires the introduction of a needle into a vein of the patient each time a specimen is taken. Repeated injection of a needle into a patient over any extended period of time leads to considerable discomfort as well as vigorous protests by the patient. The problem of obtaining specimens in obese patients is particularly acute since the veins of the patient lie buried in the subcutaneous tissue. Repeated assaults are made on a single, tiny, movable, fragile vein in the dorsum of the hand, which after the third "stick," goes into spasm, leaving only an ecchymotic area which serves as a mocking and silent testimony. Efforts have been made to relieve this discomfort in patients undergoing intravenous injections by removing the intravenous tubing at the junction with the IV needle, inserting a syringe, withdrawing a blood specimen and replacing the tubing on the IV needle. This procedure involves a certain risk in contaminating the intravenous system and the possibility of introducing foreign elements into the blood stream, in addition to being messy.
SUMMARY OF THE INVENTION
This invention provides an apparatus for periodically injecting into or removing fluid from a patient from a point remote from the veins of the patient. More particularly the invention provides medical apparatus comprising a body of material which is pierceable by a needle and self-sealing upon withdrawal of the needle and which has therein a cavity, whereby to afford removable communication with the cavity by means of a hollow needle to provide for supply or withdrawal of fluids between the cavity and a patient. The body is dimensioned such that the distance in a first plane extending through the cavity from the cavity to the outside of the body is substantially greater than the distance from the cavity to the outside of the body in a second plane extending through the cavity and perpendicularly to the first plane. In addition, the apparatus includes a plate member which is of material nonpenetrable by a needle and which is assembled to a surface of the body.
In one embodiment, the apparatus includes a wafer or disc formed from a self-sealing material with a cavity or void in the wafer connected to an intravenous needle which is adapted to be temporarily secured in a patient. Fluid is injected or removed by merely inserting a syringe needle through the self-sealing material and into the cavity. On withdrawal of the syringe needle from the cavity, the needle puncture in the wafer will be automatically closed by the self-sealing material.
This apparatus provides the patient with complete mobility during his hospital stay since the disc of self-sealing material and the intravenous needle are secured temporarily to the patient. No tourniquet is required in using this apparatus, thus virtually eliminating the possibility of obtaining spurious results. The apparatus can also be incorporated into an intravenous feeding system by connecting the cavity in the disc to a IV port in the intravenous system. The IV port can be closed when a specimen is to be taken from the cavity without disturbing any part of the intravenous feeding system.
Elimination of repeated injections into the veins of the desperately ill will salvage or preserve the veins. This is particularly significant in patients requiring injections every 2 or 3 hours.
Other objects and advantages will become apparent from the following detailed description when read in connection with the accompanying drawing in which:
FIG. 1 is an exploded view of the disc assembly for the apparatus.
FIG. 2 is a top view of the apparatus arranged for connection to an intravenous system.
FIG. 3 is a side view in section of the apparatus shown in FIG. 2.
The apparatus of this invention provides a reservoir for injecting into or removing a fluid from a patient at a point remote from the veins of a patient. More specifically, the apparatus 8 shown includes an assembly 10 having a body 18 with a cavity or void 12 connected by means of a plastic conduit 14 made of polyethylene to an intravenous needle 16 which is adapted to be injected into and left in the vein of a patient. The cavity or void 12 is formed in the body 18 with a wall of self-sealing, nontoxic, sterilizable material such as rubber. The wall of self-sealing material must be thick enough to insure a good seal. Each time fluid is to be injected into or taken from the patient, a syringe needle 20 is injected through the wall of the body 18 into the cavity 12 and the required amount of fluid is injected or is withdrawn from the cavity 12. When the needle 20 is withdrawn from the body 18, the needle will be automatically sealed by the self-sealing material, thereby preventing contamination of the apparatus.
Means are provided for protecting the assembly 10 from damage through impact while attached to the patient. In this regard, the assembly 10 is protected by means of a cover 36 and a base 30 preferably made of a plastic material and positioned in a parallel spaced relation with the body 18 positioned between the cover 36 and base 30. Various means may be used to connect the cover 36 to the base 30 and in the disclosed embodiment a pair of pegs 38 formed integral with the cover 36 extend through apertures 40 in the body 18 and are connected to the base 30. The body 18 can be made in a variety of shapes, such as a disc, wafer or doughnut with the void 12 formed in the center of the body 18. A syringe needle 20 can be inserted into the body 18 at any point on the exposed outer periphery of the disc.
Various means may be used to provide communication with the void or cavity 12 in the body 18. In the disclosed embodiment, a pair of tubes 32 are embedded in base 30 with the ends 34 of the tubes projecting upward into the cavity 12. The other ends 35 of the tubes 32 are connected to the vein of a patient and to an intravenous system. Although various means may be employed, in the disclosed embodiment the conduit 14 is used to connect the end 35 of one of the tubes 32 to the intravenous needle 16 and a second plastic conduit 22 is used to connect the end 35 of the other needle 32 to an IV port 24. All of the connections are sealed to form a closed flow path or system between the intravenous needle 16, the cavity 12, and the IV port 24 through the conduits 14 and 22. When the apparatus is used for obtaining blood specimens only, the IV port 24 is closed by means of a plug or grommet 26. Specimens can be taken from the cavity 12 in the body 18 at substantially any position around the outer circumference of the body 18 by merely inserting the syringe needle 20 through the wall of the body 18 and into the cavity 12. Although the apparatus 8 has been described as having two tubes 32 projecting into the void 12, a single tube can be used when the apparatus is used for taking blood samples only.
Means are provided for attaching the apparatus 8 to the patient to provide mobility while the patient is confined to the hospital. This means includes means for attaching the assembly 10 to the patient and means for securing the intravenous needle 16 in the patient. The assembly attaching means includes a strap or band 45 which is passed through slots 42 provided at each end of the base 30. The band 45 can be made of a strip of tape or any elastic material which can be applied to the patient. A sponge rubber backing 50 may be provided on the base 30 to cushion the assembly when mounted on the patient. The means for securing the intravenous needle 16 to the patient after injection into a vein of the patient includes a tape or strap (not shown).
In operation, the cavity 12 and tube 14 are generally filled with a neutral solution, such as a 0.9 percent saline or any balanced electrolyte solution, by inserting a syringe needle 20 or 25 into the cavity 12 or into the grommet 26 (FIG. 2). Sufficient solution is inserted to fill the cavity 12, the conduits 14 and 22 and the intravenous needle 16 to prevent the formation of an air trap or air bubble in the apparatus 8. The intravenous needle 16 is then injected into a vein in the patient and taped into position. The assembly 10 is secured to the patient at a point remote from the intravenous needle 16 and in a position convenient for injecting a syringe needle 20 into the wafer 18 by attaching the strap or band 45 to the patient. The solution in the apparatus is withdrawn to fill the conduits 14 and 22 and the cavity 12 with blood from the patient. A specimen of blood can then be taken from the cavity 12 in the body 18 by inserting the syringe needle into the cavity 12. After the blood specimen has been removed from the cavity 12, the saline solution should be re-inserted into the cavity 12 and conduit 14 and 22 to prevent clotting in the apparatus.
This apparatus can also be used as part of an intravenous system, by removing the grommet 26 from the IV port 24 and connecting the IV port 24 to intravenous tubing (not shown). Clamps 28 are provided on the conduits 14 and 22 on either side of the assembly 10 to close off the system when required. The flow of intravenous solution through the tubes 32 and the cavity 12 will provide a self-cleaning action in the cavity 12 by means of the angular deposition of the ends 34 of the tubes 32 preventing the possibility of any blood becoming stagnant in the cavity 12.
When a specimen of blood is to be taken from the cavity 12 in the wafer 10, the IV port 24 is turned off and the syringe needle 20 inserted into the cavity 12 in the wafer. The first cubic centimeter of blood withdrawn from the cavity 12 will be a mixture of blood and the intravenous solution and should be discarded. Using the same syringe needle 20 but a different syringe, the required blood specimen is withdrawn (from 10 to 20 cc. and the syringe needle 20 then removed or withdrawn from the wafer 10. The IV port 24 is turned on again to continue the introduction of the intravenous solution. The reconnection of the system for intravenous feeding flushes out the cavity 12, thus eliminating the possibility of blood becoming stagnant in the cavity 12 before the next specimen is taken.
In a specific embodiment of the apparatus, as shown in FIG. 2, the base 30 is formed from an opaque plastic that is one-eighth inch thick, 11/2 inches wide and three-fourths inches long. The tubes 32 are 19 -gauge needles and are embedded in the plastic base. The wafer or disc 18 is 11/2 inches in diameter, three-eighths inches thick with a 1/4-inch bubble or cavity in the center. The rubber consistency should be fairly firm to insure a good seal but soft enough to permit the entry and withdrawal of syringe needles of standard sizes (19-25 gauge). The polyethylene conduit is 5 inches long on the patient's side and 2 inches long on the IV side. All of the materials must be made of inert materials that will not interfere with any of the common determinations of blood.
This apparatus can also be used under conditions requiring repeated injections of IV medication. The most common of these is the repeated injection of heparin every 4 to 6 hours. The cavity 12 and conduit 14 are first primed or charged with heparin instead of the saline solution and subsequent doses of heparin are given by piercing the wafer 18 and injecting the heparin into the cavity 12. Other uses can be made of the apparatus where repeated injection or sampling is required.