WO2008126966A1

WO2008126966A1 - Vascular access apparatus

Info

Publication number: WO2008126966A1
Application number: PCT/KR2007/004906
Authority: WO
Inventors: Byoung-Goo Min; Seung-Hee Lee; Jung-Chan Lee; Jeong-Chul Kim; Ki-Moo Lim; Wook-Eun Kim; Seong-Wook Choi; Yong-Soon Won; Jong-Weon Choi
Original assignee: Bhk
Priority date: 2007-04-13
Filing date: 2007-10-09
Publication date: 2008-10-23
Also published as: KR20080092753A; KR100876650B1

Abstract

Disclosed is a vascular access apparatus including a needle having an internal lumen to communicate with a blood passage and implanted in the patient's body, a driving part for transporting the needle in a manner such that the needle tip is expelled from the patient's body, and a controlling part for controlling the operation of the driving part in response to a signal. The vascular access apparatus is advantageous in that it is convenient to use because needle insertion and removal motions are automatically performed, repetition of needle piercing is not required because the needle can be precisely inserted into a target position, it is possible to reduce the number of needle piercing motions, thus reducing the number of times that pain is applied to a patient, and it is possible to alleviate the degree of pain applied to a patient because needle piercing is performed without being anticipated by the patient.

Description

[DESCRIPTION]

(Invention Tit Ie]

VASCULAR ACCESS APPARATUS

[Technical Field]

<i> The present invention relates to a vascular access apparatus for use in a hemodialysis process, the apparatus being implanted under the skin of a patient in order to extract patient' s blood and supply external blood to a patient's body, and more particularly, to a vascular access apparatus for use in a hemodialysis process, in which an introduction needle for introducing external blood into a patient' s body and an extraction needle for extracting blood from the patient's body are movably arranged so that they are implanted under the skin, and are driven to puncture the skin and thus protrude from the patient 's skin.

[Background Art]

<2> The kidney in a human body has a variety of functions, such as a function of filtrating and evacuating metabolic waste from a human body, a function of maintaining acid-base equilibrium, a function of producing and excreting hemopoitic hormones, or the like. Accordingly, if kidney malfunction occurs, blood vessels are clogged up in the manner that a sewer pipe clogs, because waste is accumulated in blood, leading to uremia. Thus, the person with the kidney malfunction finally comes to die. Accordingly, it is impossible to save the life of an end-state renal failure patient if the patient cannot get any of the following treatments: transplantation of a living kidney, peritoneal dialysis, and hemodialysis using an artificial kidney apparatus which is installed outside a patient's body and performs the function of a living kidney. Auxiliary treatments using chemicals accompany the aforementioned treatment in order to treat other symptoms of the patient, such as the over-accumulation of phosphorous or potassium, or anemia. Because it is unlikely for a donor of a living kidney to be found in a given country, most patients with kidney malfunction continue living by getting hemodialysis treatment. Further, patients suffering from diabetes also get the same treatment as patients with kidney malfunction when their kidneys do not normally function.

<3> The mot important part of the artificial kidney apparatus is a dialyzer, which has a bunch of hollow fibers and in which blood and dialysate contact each other with a septum interposed therebetween, thereby filtrating waste from the blood and adding electrolytes to the blood. The dialysis capability of the artificial kidney apparatus is very good in comparison with living kidneys, but the artificial kidney is disadvantageous in that a patient must undergo dialysis at rigid times, for example, two to three times a week for four to six hours each time, because it is impossible to carry the artificial kidney apparatus.

<4> When hemodialysis treatment is performed, blood is first extracted from a patient's body, purified, and then returned to the patient's body. At this time, a vascular access apparatus which extracts and returns blood from and to the patient's body must be used.

<5> Until now, vascular access is established generally by means of central venous access using a catheter and of the formation of arterio-venous fistula in the arms, and many efforts have been made to facilitate permanent use thereof .

<6> Hereinafter, a vascular access apparatus according to a related art will be described with reference to the accompanying drawings.

<7> FIG. 1 is a perspective view illustrating a vascular access apparatus according to a related art, and FIG. 2 is a sectional view illustrating exemplary use of the vascular access apparatus according to the related art.

<s> The vascular access apparatus shown in FIG. 1 i^~s disclosed in U.S. Patent Publication No. 2007/0016162, entitled Valve Port and Method for Vascular Access. The valve port for vascular access includes a flexible conduit 14 having an end elongated to terminate at a right atrium and a base 12 which is connected to the other end of the flexible conduit 14 and which is provided with an opening 36 through which a needle N can be introduced.

<9> The valve port 10 having the aforementioned configuration is implanted under the skin S of a patient at a position close to the collarbone. The valve port 10 is constructed to pass through the skin S, puncturing the skin S from outside, and to function to extract blood from a patient and return treated blood to the patient through the needle N communicating with the opening 36 of the base 12.

<io> The use of the valve port for vascular access having the aforementioned structure is advantageous in that it makes hemodialysis treatment convenient because it is possible to extract and return blood from and to a patient's body just by performing a simple action of coupling the needle N to the base 12. It is further advantageous in that the patient can enjoy his or her usual activities, such as taking a bath, swimming, or the like right after the hemodialysis treatment because the opening of the valve port is closed when the needle N is removed).

<π> However, the use of the valve port for vascular access is also disadvantageous in the following aspect. That is, when establishing vascular access, an operator must precisely sense the position of the base 12 by touching the patient's skin and then pierce the skin of the patient with the needle N at the position of the base 12, so that the needle N is precisely introduced into the opening 36 of the base 12. However, it is difficult for an unskilled operator to insert the needle N into the opening 36 in one attempt because the operator must sense the position of the base 12 only by touching the patient's skin, but cannot visually observe the base 12 with the eyes. Accordingly, generally needle piercing is repeated a couple of times when an unskilled operator conducts the vascular access, thereby causing much discomfort to patients. Further, events in whrch even skilled operators cannot precisely insert the needle N into the opening 36 in one attempt frequently occur because there are times when the skilled operators cannot concentrate on the needle piercing for some reason.

<12> Further, when performing hemodialysis treatment using the related art apparatus, two vascular access apparatuses (a vascular access apparatus for transferring patient' s blood to a dialyzer and a vascular access apparatus for returning purified blood to the patient) are required. Accordingly, in the case in which two vascular apparatuses are used, two needle piercing actions are conducted, so that a patient is exposed to more frequent pain. [Disclosure] [Technical Problem]

<13> Accordingly, the present invention has been devised in consideration of the aforementioned problems and conditions, and it is a feature of the present invention to provide a vascular access apparatus which is capable of preventing improper needle piercing from being performed, reducing the number of needle piercing actions to half in comparison with the case of using the vascular access apparatus of the related art, thereby reducing the number of times that pain is applied to a patient, and alleviating the degree of pain applied to a patient . [Technical Solution]

<i4> In order to solve the various problems encountered in the known art, and in order to achieve the above described advantageous effects and features, in accordance with the present invention, there is provided a vascular access apparatus, including a needle having an internal lumen and implanted into a patent' s body so as to communicate with a blood passage in a patient' s body, and a driving unit for transporting the needle in a manner such that the tip of the needle is expelled from the patient' s body to be disposed outside the patient' s body.

<15> It is preferable that the needle include a first needle for extracting patient' s blood and a second needle for introducing external blood into the •patient' s body.

<16> It is preferable that the vascular access apparatus include two or more needles, two or more blood passages, and two or more gate blocks, the two or more needles being installed on a single transportation block.

<17> It is preferable that the driving unit be implanted in the patient' s body and that the vascular access apparatus further include a control unit for controlling the operation of the driving unit in response to an externally transmitted signal.

<18> It is preferable that the vascular access apparatus further include an external signal transmission device for transmitting a signal in a wireless manner to the control unit.

<19> It is preferable that the driving unit includes the gate block which is movably constructed and controls the blood passage so that it is linked with or isolated from the internal lumen of the needle, a transportation block on which the needle is mounted, and a motor for transporting the transportation block in a manner such that the tip of the needle is introduced into the patient's body or is expelled from the patient's body to be disposed outside the patient' s body.

<20> It is preferable that the gate block be structured in a manner such that it can be transported by the transportation block, and that the gate block have a gate lumen which is usually in a first position in which it can communicate with the internal lumen of the needle but is selectively placed in a second position in which it can communicate with the blood passage when the transportation block is transported in a manner such that the tip of the needle is driven to be expelled from the patient' s body and disposed outside the patient' s body.

<2i> It is preferable that the driving unit be structured to sequentially perform actions of transporting the transportation block in a manner such that the tip of the needle is driven to be expelled from the patient' s body and disposed outside the patient' s body and of further advancing the transportation block so that the blood passage and the internal lumen of the needle come to communicate with each other.

<22> It is preferable that the vascular access apparatus further include an elastic member which imparts elastic force to the gate block in a direction in which the gate block advances so that the gate lumen is isolated from the blood passage. [Advantageous Effects]

<23> The vascular access apparatus of the invention is an apparatus for extracting patient' s blood and introducing external blood to a patient' s body in order to transfer the patient' s blood to a hemodialysis apparatus and return the blood treated by the hemodialysis apparatus to a patient' s body, the apparatus being implanted in the patient' s body.

<24> When extracting blood from the patient' s body and returning the blood to the patient' s body after treatment of the blood, a needle which has an internal lumen and which is subcutaneousIy introduced into the patient' s body must be used. In the related art vascular access apparatus shown in FIG. 1 and FIG. 2, a needle is subcutaneousIy introduced into a patient' s body. However, in the vascular access apparatus according to the invention, a needle is implanted in the patient' s body and normally remains in the patient' s body and is driven to be expelled from the patient' s body through the skin of the patient' s body. [Description of Drawings]

<25> FIG. 1 is a perspective view illustrating a vascular access apparatus according to the related art;

<26> FIG. 2 is a cross-sectional view illustrating an exemplary use of the vascular access apparatus according to the related art;

<27> FIG. 3 is a cross-sectional view illustrating a vascular access apparatus according to a first embodiment of the present invention!

<28> FIG. 4 is a cross-sectional view illustrating the vascular access apparatus according to the first embodiment of the present invention, in which the tip of a needle is expelled from a patient's body to be disposed outside the patient's body;

<29> FIG. 5 is a cross-sectional view illustrating the vascular access apparatus of the invention, to which a tube of a hemodialysis apparatus is coup1ed;

<30> FIG. 6 is a cross-sectional view illustrating the vascular access apparatus of the invention, which is in a state in which the blood of a patient can be introduced and extracted;

<3i> FIG. 7 is a cross-sectional view illustrating a vascular access apparatus according to a second embodiment ;

<32> FIG. 8 is a cross-sectional view illustrating the vascular access apparatus according to the second embodiment, in which a needle is transported upward; and

<33> FIG. 9 is a cross-sectional view taken along line A-A, shown in FIG. 8. [Best Mode]

<34> Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

<35> The internal structure of a vascular access apparatus of the invention will be described below.

<36> FIG. 3 shows a vascular access apparatus according to a first embodiment of the invention.

<37> As shown in FIG. 3, the vascular access apparatus according to the invention includes a needle 100 having an internal lumen which can be linked with a blood passage 200 in a patient' s body and which is implanted in a patient's body, a driving unit 300 for actuating the needle 100 in a manner such that the tip of the needle is expelled from the patient's body through the skin of the patient to be disposed outside the patient's body, and a control unit implanted in the patient's body for controlling the operation of the driving unit 3000 in response to an external signal. All of the above elements are installed in a housing 600, and the housing 600 is implanted in the patient 's body.

<38> The blood passage 200 is a device for transferring the patient' s blood to the needle 100. The blood passage 200 takes a form in which the end thereof communicates with the right atrium of a patient, like the^* flexible conduit in the related art (refer to reference numeral 14 in FIG. 1 and FIG. 2), and the other end communicates with the needle 100. The blood passage 200 is desirably made of material having biocompatibility. The blood passage 200 is not limited in the kind thereof, for example, it is not limited to particular artificial articles or living organs, as long as blood can pass therethrough. <39> The needle 100 includes a first needle 110 for extracting patient's blood flowing out through the blood passage 200 and a second needle for introducing external blood to a patient's body. The first needle 110 and the second needle 120 are desirably provided in replaceable form, so that they can be replaced when they are degraded after they have been used many times.

<40> The end of each of the first needle 110 and the second needle 120 has a sharp tip so that it can penetrate the patient's skin S and the other end of each of the first needle 110 and the second needle 120 are linked with a first blood passage 210 and a second blood passage 220 via a first connection tube 132 and a second connection tube 134, respectively. Accordingly, the patient's blood transferred through the first blood passage 210 is discharged through the first connection tube 132 and the first needle 110, is then subjected to dialysis treatment, and is finally returned to the patient' s body through the second needle 120 and the second connection tube 134.

<4i> In the vascular access apparatus according to this embodiment, each of the needle 100, the connection tube 130, and the blood passage 200 is provided as a pair, but the number of connection tubes 130 engaged with the needle 100 is not limited, but is freely variable. For example, in the case in which the patient's blood is only extracted, or in the case in which external blood is only introduced into the patient's body, only a single needle 100 and a single connection tube 130 are needed. Further, the number of each of the first needle 110, the first connection tube 132 and the first blood passage 210 for extracting the patient's blood can be plural (two or more), and the number of each of the second needle 120, the second connection tube 134 and the 'second blood passage 220 for introducing external blood to the patient's body also can be plural (two or more).

<42> The driving unit 300 is an element for transporting the needle 100 installed in the housing 600 in a manner such that the tip of the needle 100 is expelled from the patient's body, penetrating through the skin S of the patient to be disposed outside the patient' s body. The driving part 300 includes a gate block 310 which is structured so as to be able to move in the direction in which the needle 100 travels and which determines linkage and isolation between the blood passage 200 and the internal lumen of the needle 100 by the position thereof, a transportation block 320 to which the other end of the needle 100 is coupled, a motor 330 for transporting the transportation block 320 in the direction in which the needle 100 travels, and a battery pack 340 for supplying electric power to the motor 330.

<43> The motor 330 and the transportation block 320 are coupled in a manner such that a driving force is transferred by a gear unit and rotating force generated by the motor 330 is changed to linear force by the gear unit. That is, when the motor 330 starts, the transportation block 320 is transported upward or downward depending on the rotation directions of the motor 330.

<44> The transportation block 320 has a pressing plate 322 laterally extending from the lower end thereof. Accordingly, when the transportation block 320 is transported upward, the gate block 310 is pushed by the pressing plate 322, so that the gate block 310 moves upward together with the transportation block 320. The pressing plate 322 can take any forms and sizes as long as it can make the gate block 310 move.

<45> The gate block 310 has a gate lumen 316 in the form of a penetration hole so that blood can pass therethrough. One end of the gate lumen 316 is engaged with the connection tube 130, and the other end thereof is selectively engaged with the blood passage. In detail, the gate lumen 316 always communicates with the internal lumen of the needle 100, but selectively communicate with the blood passage only when the transportation block 320 is transported in a manner such that the tip of the needle 100 is expelled from the patient's body to be disposed outside the patient's body.

<46> AS shown in FIG. 3, in a first position, in which the needle 100 is completely introduced into the patient's body, the blood passage 200 and the gate lumen 316 are not linked with each other, and thus blood in the blood passage 200 is not transferred to the needle 100. Conversely, in a second position, in which the tip of the needle 100 is expelled from the patient's body, penetrating through the patient's skin S in order to extract or introduce blood, the blood passage 200 and the gate lumen 316 are linked with each other. Thus, the blood in the blood passage 200 is transferred to the needle 100. The mechanism in which the blood passage 200 and the gate lumen 316 are linked with each other or isolated from each other will be described in detai 1 below.

<47> The housing 600 is introduced into the patient's body and remains under the skin of the patient. The lower surface of the housing 600 is safely placed on the fascia. The lower surface of the housing 600 is provided with a ring-shaped safe-placement portion 630 having an empty space in the center thereof. Accordingly, when the housing 600 is safely placed on the fascia, fibrous tissue grows from living organs around the ring-shaped safe-placement portion 630 and becomes tangled around the ring-shaped safe-placement portion 630. Thus, the housing 600 can be more stably fixed on the fascia.

<4S> In this embodiment, the safe-placement portion 630 has a ring shape, but it can have a hook form, in which a portion thereof is open.

<49> FIG. 4 shows an exemplary use of the vascular access apparatus according to the first embodiment. In FIG. 4, the tip of the needle 100 is protruded from the patient's skin S to be disposed outside the patient' s body after passing through the patient's skin S. FIG. 5 shows another exemplary use of the vascular access apparatus according to the first embodiment, in which a hemodialysis apparatus 700 is coupled to the vascular access apparatus of the invention. FIG. 6 shows a further exemplary use of the vascular access apparatus according to the first embodiment, in which the vascular access apparatus is in a position in which patient's blood can be extracted and external blood can be introduced into' a patient's body.

<50> From the state shown in FIG. 3, when the controlling part 400 receives a first driving signal, the controlling part 400 controls the motor 330 to start, and rotating force generated from the motor 300 is changed to linear force by the gear unit, thereby transporting the transportation block 320 upward, as shown in FIG. 4. At this time, the vascular access apparatus of the invention may further includes an external signal transmission device which allows a user to easily transmit a signal to the control unit 400 in a wireless manner.

<5i> When the transportation block 320 is transported upward, since the first needle 110 and the second needle 120 are coupled to the transportation block 320, the first needle 110 and the second needle 120 are also transported upward, tips of the first needle 110 and the second needle 120 come to protrude from the patient's skin after passing through a first opening 610 and a second opening 620 formed in the housing 600, respectively, and through the patient's skin S. The first opening 610 and the second opening 620 are configured to be laterally spaced apart from each other when the needle 100 is introduced into the patient's body. Further, it is desirable that the first opening 610 and the second opening 620 have a function of securing the needle 100 so that it does not shake in a lateral direction when the tip of the needle 100 is expelled to be disposed outside the patient's body after passing through the patient's skin. The first needle 110 and the first opening 610 are engaged with sealing means 640 and the second needle 120 and the second opening 620 are engaged with sealing means 640. The sealing means 640 takes the form of a tube with an internal lumen therein and prevents a variety of liquids from leaking in the space between the needle 100 and the openings 610 and 620.

<52> In the use of the vascular access apparatus of the invention, in which the needle 100 stays in the patient's body and then protrudes from the patient's skin S after passing through the patient's skin S when a signal is transmitted, there is no need to try to precisely introduce the needle N into the opening 36, as shown in FIG. 1 and FIG. 2. Accordingly, even an unskilled operator can easily extract patient's blood and return the patient's treated blood to a patient's body.

<53> When using the vascular access apparatus of the invention, the needle is precisely inserted into a target position of a patient's body in one attempt. Thus, there is no need to conduct needle piercing motions a plurality of times, unlike the case of using the related art vascular access apparatus, thereby reducing pain applied to patients every time a needle is inserted into a patient's body. In addition, when using the vascular access apparatus of the invention, even if a needle is inserted into and removed from the patient's skin many times, only a single hole is formed in the patient's skin. Accordingly, skin damage and infection are decreased.

<54> Further, the related art vascular access apparatus is limited to an overall circular shape in order to allow an operator to easily sense the precise position of the opening 36, whereas the vascular access apparatus of the invention can take a variety of forms because there is no need to precisely sense the positions of the first opening 610 and the second opening 620. Still further, it is possible to vary the position where the tip of the needle 100 protrudes and the direction in which the tip of the needle 100 travels to create circumstances under which it is convenient to use the vascular access apparatus.

<55> Yet further, the vascular access apparatus of the invention is preferably configured in a manner such that only the needle 100 need be replaced when the needle 100 is degraded over time. In such a case, it is preferable that the needle have sharp tips at the lower and upper ends thereof because the lower end of the new needle 100 must penetrate the skin S of the patient to be engaged with the transportation block 320 when the new needle 100 is driven downward for new needle installation.

<56> When the pressing plate 322 comes into contact with the gate block 310 in a state in which the needle 100 is completely introduced in the housing 600, as shown in FIG. 3, the gate block 310 and the transportation block 320 are raised together, thereby linking the blood passage 200 and the gate lumen 316 to each other as soon as the tip of the needle 100 protrudes from the skin S, passing through the skin S, as shown in FIG. 4. Thus, there is a risk that blood will be discharged through the needle 100 before the tube 700 of the hemodialysis apparatus is coupled to the needle 100.

<57> In order to avoid the aforementioned problem, the pressing plate 322 and the gate block 310 are spaced apart from each other with a predetermined gap therebetween, and the driving unit 300 operates to raise the transportation block 320 only until the pressing 322 does not push the gate block 310 upward. Accordingly, even if the transportation block 320 is continuously transported until the state shown in FIG. 4 comes to be established, that is, until the pressing plate 322 comes into contact with the lower surface of the gate block 310, the state in which the blood passage 200 and the gate lumen 136 are isolated from each other is maintained because the gate block 310 is not moved upwards. When the tip of the needle 100 is protruded from the skin S, as shown in FIG. 4, an operator couples the tube of the hemodialysis apparatus to the needle 100, as shown in FIG. 5.

<58> When the tube of the hemodialysis apparatus is engaged with the needle 100, the user manipulates the external signal transmission device to transmit a second driving signal to the control part 400. After receiving the second driving signal, the control part 400 controls the driving part 300 to drive the transportation block 320 and' the gate block 310 to be raised until the blood passage 200 and the gate lumen 316 are linked, as shown in FIG. 6. That is, the driving part 300 included in the vascular access apparatus of the invention is configured in a manner of sequentially performing a first action of transporting the transportation block 320 so that the tip of the needle 100 is expelled from the patient's body to protrude from the skin of the patient, and a second action of further advancing the transportation block 320 so that the tip of the needle 100 protrudes more and the blood passage 200 and the internal lumen of the needle 100 are linked with each other.

<59> When the blood passage 200 and the gate lumen 316 are linked with each other, as shown in FIG. 6, the blood in the first blood passage 210 is transferred to the hemodialysis apparatus (not shown) via the gate lumen 316 of the first gate block 312, the first connection tube 132 and the first needle 110 in turn, and then the blood, passing out the hemodialysis apparatus, is returned to the patient's body via the second needle 120, the second connection tube 134, the gate lumen 316 of the second gate block 314 and then the second blood passage 220. At that time, the vascular access apparatus of the invention may further includes a clamp for clamping the needle 100 protruding from the skin S of the patient so that it is not reintroduced into the patient's body.

<60> When trying to reintroduce the needle 100 into the housing 600 from the state shown in FIG. 6, an operator manipulates the external signal transmission device to transmit a needle downward motion signal to the control part 400 so that the needle 100 moves downward. The control part 400, having received the needle downward motion signal, drives the motor 300 to rotate in a reverse direction so that the transportation block 320 is transported downward. At this time, since the transportation block 320 and the gate block 310 are coupled to each other, the gate block 310 does not move downward even if the transportation block 320 is transported downward. Thus, the linked state of the blood passage 200 and the gate lumen 316 is maintained.

<6i> Accordingly, the vascular access apparatus of the invention further includes an elastic member 500 which imparts elastic force to the gate block 310 in a downward direction, so that the blood passage 200 and the gate lumen 316 are isolated from each other by a motion such that the gate block 310 moves downward when the transportation block 320 is transported downward. The elastic member 500 includes a first elastic member 510 for restoring the position of the first gate block 312 and a second elastic member 520 for restoring the position of the second gate block 312.

<62> An upper end portion of the elastic member 500 is coupled to the housing 600 and a lower" end portion of the elastic member 500 is coupled to the gate block 310. Thus, when the gate block 310 moves upward so that the blood passage 200 and the gate lumen 316 are linked with each other, the lower end portion of the elastic member 500 is forced upward and thus the elastic member contracts, as shown in FIG. 6. Conversely, when the transportation block 320 is moved downwards, the elastic member 500 expands to recover its original state, thereby isolating the blood passage 200 from the gate lumen 316 by forcing the gate block 310 downward, as shown in FIG. 3. At this time, if the elastic member 500 has excessive elasticity, upward motion of the gate block 310 cannot smoothly be established. Conversely, if the elasticity of the elastic member 500 is insufficient, downward motion of the gate block 310 cannot smoothly be established. Accordingly, .the elasticity of the elastic member 500 must be properly set according to the driving force of the driving unit 3000 and the characteristics of other elements.

<63> According to the vascular access apparatus of the invention, a needle introduction motion and a needle expelling motion are automatically performed. ^' Accordingly, the risk of medical accidents which occur as a result of needle insertion and needle removal actions is decreased. Further, since the needle insertion and removal motions are performed without being anticipated a patient, it is therefore possible to alleviate the pain of a patient .

<64> FIG. 7 shows a cross-section of a vascular access apparatus according to a second embodiment of the invention. FIG. 8 shows a cross-section of the vascular access apparatus with the tip of the needle which is transported upward. FIG. 9 shows a section of the vascular access apparatus, taken along line A-A shown in FIG. 8.

<65> As shown in FIG. 7, the vascular access apparatus of the invention can be configured in a manner such that the first blood passage 210 and the second blood passage 220 are directly linked with the first needle 110 and the second needle 120, respectively. The blood passage 200 is configured to be open or closed by the elastic force of the elastic member 500. That is, the gate block 310 provided to the end portion of the elastic member 500 presses the blood passage 200 using the elastic force of the elastic member 500, and the blood passage 200 is closed as the portion which is pressed by the gate block 310 is squashed flat.

<66> The internal lumen of the needle 100 is normally filled with an aqueous anticoagulant solution for preventing blood from coagulating, and heparin and an antiseptic solution for cleansing the needle. Accordingly, when the needle 100 is disposed under the skin, as shown in FIG. 7, if the blood passage 200 is closed by contraction thereof, the aqueous anticoagulant solution, heparin and antiseptic solution do not leak from the needle 100.

<67> When the transportation block 320 and the needle 100 are transported upward by the driving part 300 from the positions shown in FIG. 7, the gate block 310 is pulled upward by the action of the pressing plate 322 provided to the lower end of the transportation block 320 and thus the blood passage 200 is restored to its original state, i.e. to the open state, as shown in FIG. 8 and FIG. 9. For this reason, the blood passage 200 is made of material having elasticity so that it restores its original state when external force is released.

<68> As described above, when the vascular access apparatus has a configuration in which the blood passage 200 is directly coupled to the needle 100 and the opening and closing of the blood passage 200 is controlled by the elastic member 500, the gate lumen 316 and the connection tube 130 shown in FIG. 3 and FIG. 6 are needed, and thus the structure of the vascular access apparatus can be simplified and malfunction and disorder thereof can be remarkably decreased.

<69> While the description above is directed particularly to use of the vascular access apparatus for hemodialysis, it will be appreciated that the invention can be applied to other uses, for example, the introduction of anti-cancer medicine to a patient's body.

<70> It will be apparent to those skilled in the art that the present invention is' not limited to the aforementioned embodiments, but that various modifications and variations to the embodiments may be made without departing from the spirit or scope of the invention. Accordingly, it is intended that the present invention cover the modifications and variations of this invention provided they fall within the scope of the appended claims and their equivalents. [Industrial Applicability! <7i> According to the invention, a needle introduction motion and a needle expelling motion are automatically performed, and thus it is convenient to use the vascular access apparatus. Since the needle can be precisely inserted at a target position, there is no need to repeat needle piercing motions many times. Further, a plurality of needles can pierce a patient's body at one time. For these reasons, it is possible to reduce the number of needle piercing motions, which cause pain to a patient. Still further, since the needle introducing and expelling motions are performed in a manner not anticipated by a patient, it is possible to alleviate the degree of pain of a patient.

<72> In addition, when using the vascular access apparatus of the invention, even after a needle is inserted in and removed from the patient's skin many times, only a single hole is formed in the patient's skin. Accordingly, it is possible to reduce skin damage and infection.

<73> Still in addition, since it is possible to freely vary the position where the tip of the needle is inserted in the patient's skin and the direction in which the tip of the needle 100 travels, the vascular access apparatus of the invention may be implemented in a variety of designs.

Claims

[CLAIMS] [Claim 1)

<75> A vascular access apparatus, comprising-'

<76> a needle which has an internal lumen to communicate with a blood passage in a patient body and which is implanted in a patient's body; and

<77> a driving part for transporting the needle in a manner such that a tip of the needle is expelled from the patient's body to be disposed outside the patient 's body.

[Claim 2]

<7S> The vascular access apparatus according to claim 1, wherein the needle comprises a first needle for extracting patient's blood and a second needle for introducing external blood to the patient's body.

[Claim 3]

<79> The vascular access apparatus according to claim 1, wherein the driving part comprises a gate block having a movable structure for controlling linkage and isolation between the blood passage and the internal lumen of the needle, a transportation block on which the needle is mounted, and a motor for transporting the transportation block such that the tip of the needle is inserted into and removed from the patient's body.

[Claim 4]

<80> The vascular access apparatus according to claim 3, wherein the number of each of the needle, the blood passage, and the gate block is two or more and wherein the two or more needles are mounted on a single transportation block. -

[Claim 5)

<si> The vascular access apparatus according to claim 3, wherein the gate block is configured to be able to move by action of the transportation block, and wherein the gate block has a gate lumen which is always linked with the blood passage but is selectively linked with the internal lumen of the needle only when the transportation block is transported, to thus expel the tip of the needle from the patient's body to be disposed outside the patient's body.

[Claim 6]

<82> The vascular access apparatus according to claim 3, further comprising an elastic member for imparting elastic force to the gate block in a direction in which the gate block advances in order to isolate the gate lumen from the blood passage.

[Claim 7]

<83> The vascular access apparatus according to claim 1, further comprising an elastic member for closing the blood passage by pressing the blood passage when the needle is' disposed under the patient's skin and for opening the blood passage by releasing pressure applied to the blood passage when the tip of the needle 1000 is expelled from the patient's body to be disposed outside the patient 's body.

[Claim 8]

<84> The vascular access apparatus according to claim 7, wherein the driving part comprises a transportation block on which the needle is mounted and a motor for transporting the transportation block such that the tip of the needle is inserted into and removed from the patient's body, and

<85> wherein the transportation block releases pressure applied to the blood passage by contracting the elastic member when the tip of the needle is transported to be expelled from the patient's body.

[Claim 9]

<86> The vascular access apparatus according to any one of claims 1 to 8, wherein the driving part sequentially performs a first action of transporting the transportation block so that the tip of the needle is expelled from the patient's body to be disposed outside the patient's body, and a second action of further advancing the transportation block so that the tip of the needle further protrudes from the patient's body and the blood passage and the internal lumen of the needle are linked with each other.

[Claim 10]

<S7> The vascular access apparatus according to any one of claims 1 to 8, wherein the driving part is implanted into the patient's body and wherein the vascular access apparatus further comprises a control part for controlling operations of the driving part in response to an externally transmitted signal.

[Claim 11]

<88> The vascular access apparatus according to claim 8, further comprising an external signal transmission device which transmits a signal to the control part in a wireless manner.

[Claim 12]

<89> The vascular access apparatus according to any one of claims 1 to 8, wherein the needle is installed in a manner such that it can be replaced with another one.

[Claim 13]

<90> The vascular access apparatus according to claim 12, wherein both ends of the needle are sharp.

[Claim 14]

<9i> The vascular access apparatus according to any one of claims 1 to 8, further comprising a housing implanted into the patient's body for encasing the needle and the driving part,

<92> wherein the tip of the needle penetrates the housing when it is expelled from the patient's body.

[Claim 15]

<93> The vascular access apparatus according to claim 14, wherein a lower surface of the housing is placed on a fascia after being introduced under the patient's skin and the lower surface has a safe-placement portion having a ring shape or a hook shape.

[Claim 16]

<94> The vascular access apparatus according to claim 14, wherein the housing has openings through which the needle passes, and sealing means is provided in gaps between the needle and the openings.