Blood vessel punch

Abstract

The present invention is a novel vascular punch that uses a positive pressure force to separate the tissue of the target blood vessel. The present invention is specifically designed to punch large round holes in vascular surgery without causing heavy bleeding. The side-biting punch mechanism realizes a punching method that uses positive force cutting to achieve a neat incision without wear. The side-biting vascular punch includes a U-shaped razor blade, a baffle for stopping the blade, and a linkage mechanism that brings the razor blade to the surface of the baffle, which forms an aligned contact line that can generate positive pressure to cut the tissue on the target blood vessel. The semi-rigid pad installed on the baffle can reduce errors during part manufacturing and assembly, and the adjustable baffle can further improve the formation of the cutting line to improve cutting efficiency. The best embodiment of the side-biting punch includes a four-bar linkage and a scissor-like single pivot mechanism, and the handle drives the side-biting punch action and generates the required cutting force. The former realizes translational bite cutting, and the latter realizes rotational bite cutting of the razor blade and the baffle.

Description

Technical Field

[0001] The present invention generally relates to perforating blood vessels associated with cardiovascular surgery, and more specifically, to producing a large circular opening (usually a hole with a diameter greater than 6 mm); however, currently available blood vessel perforators on the market are not able to produce satisfactory large holes. Background Art

[0002] Ventricular assist device (VAD) is a form of mechanical circulatory support that has entered a mature stage and can be considered the standard of care for advanced heart failure. Circulatory support is achieved by a pulsatile or continuous blood pump that first draws blood from the heart, then pressurizes it through the VAD to provide energy, and finally returns it to the human circulation. The blood flow pressurization process of this mechanical circulatory assistance requires an artificial flow channel (such as a graft) that connects a first (inflow) end next to the assist device and a second (outflow) end that is anastomosed to the arterial wall. The success of VAD implantation depends on many factors, among which the anastomosis of the graft is a key factor, which is affected in different ways by surgical skills and special tools that help achieve a satisfactory anastomosis.

[0003] The catheter of the VAD graft is usually made of Dacron, polytetrafluoroethylene (PTFE) or silicone, etc., and can be connected to the artery in the ascending or descending aorta in an end-to-side manner. The diameter of the above-mentioned catheter is large, usually in the range of about 15-20 mm. During the surgical operation, the surgeon first uses a scalpel to cut an incision in the aortic wall that is equivalent to the size of the hole, then trims the edges of the incision with scissors, and finally sews the graft and the cut and enlarged vascular opening stitch by stitch. The quality of the end-to-side anastomosis usually depends on the vascular tools provided, the surgeon's skills and the allowed surgical methods. For a surgeon to complete this anastomosis, the size and neatness of the incision and the trimming of the edges of the vascular wall opening are important. During suturing, an incision that is too large or too small or irregularly enlarged around the incision may cause the edges of the graft connected to the host vessel to not match, resulting in distortion or wrinkles in the connection of the anastomosed tissue layers. Poor anastomosis between the end and the side may cause bleeding during surgery or cause thrombosis in the later stages of surgery due to unevenness and wrinkles at the connection between the graft and the host. Unfortunately, there is no large aortic punch that can help surgeons safely and effectively punch a hole that is large enough and has no edge wear, which can serve as a good basis for ensuring high-quality graft connection.

[0004] As of today, aortic punchers that can punch small holes (less than 6 mm in diameter) in the aortic wall have been developed and are used clinically, particularly in coronary bypass surgery. Typically, these minor surgical punchers consist of a slidable anvil rod and a cutting tube coupled thereto. First, a needle (anvil or iron) is inserted into the aorta through a small incision made in the vessel wall. Then, the anvil is pulled against the cutting tube to generate shear forces, and the cutting tube accommodates the anvil and its support rod very tightly. The fingers and palms must exert a large force to complete the punching action. Clinically, it is found that the most difficult part to be neatly separated is the adventitia. Therefore, in order to overcome the difficulties encountered in vascular punching, some new methods have been proposed, including razor-like tubes or anvil cutters to increase the shear force during the cutting process; introducing rotational motion relative to the sliding cutting action caused by the engagement of the anvil and cutting tube; and amplifying the shear force through a pistol-like handle and trigger mechanism.

[0005] The small vascular punch proposed by the above mechanical principles and methods and the prior art cannot make a larger hole in the artery. There are two main reasons: First, when an incision as large as 10-20 mm is formed on the artery, hemostasis becomes a problem. In the case of a large opening, a large amount of bleeding will occur due to the high arterial blood pressure, and this type of bleeding is usually not allowed to occur in cardiovascular surgery. Even if the bleeding can be stopped temporarily, the subsequent insertion of the anvil will inevitably make the incision open wider, resulting in more serious and uncontrollable bleeding. Secondly, the mechanism that provides the shear force required for tissue separation will not be suitable for cutting larger holes, because the area of ​​action of the shear force may be greatly increased, and greater hand pressure will need to be applied, which is usually beyond the power that human hands can easily provide.

[0006] For the above reasons, there is a need to invent a large blood vessel punch using a different cutting mechanism and design principle. During the formation of a large opening on an artery, not only does it require quick and neat separation of tissue, but it also requires ensuring hemostasis to avoid heavy and uncontrollable bleeding. Summary of the invention

[0007] An object of the present invention is to provide a surgical instrument capable of making large holes in blood vessels, wherein the incision of the hole is clean and in the correct position without wear.

[0008] Another object of the present invention is that the force required to complete the punching action of the above-mentioned device is not too great and can be easily done by hand.

[0009] Another purpose of the above instrument is that the excised tissue can be retained in the instrument after perforation.

[0010] Another object of the present invention is to ensure hemostasis (absence of bleeding) when the present invention is used together with a partially clamped vascular clamp (hemostatic forceps) without interfering with each other.

[0011] According to the above design requirements, the present invention provides a blood vessel punch, which includes a side-bite cutter and a handle that can amplify the cutting force applied by the hand. The side-bite cutter is composed of a U-shaped razor blade and a baffle. Figure 1a and Figure 1b As shown. Unlike conventional vascular punches that use shear force to separate tissue, the side-biting punch of the present invention uses normal force to achieve a clean cut. The normal stress acting on the tissue to be cut is the applied force F divided by the area A that the tip of the razor blade is in normal contact with. Because the blade edge is usually very thin, this cutting contact force is usually very large. In the design of the side-biting cutter, the contact pattern and characteristics of the blade edge relative to the support baffle are the key to achieving a clean cut.

[0012] exist Figure 2a , 2b , 2c depict three basic failure modes that result in poor side-bite cutting. Failure mode A describes a situation where the contact between the razor blade and the baffle is incomplete. Assuming that the baffle surface is not completely rigid, and the razor blade can cut into the shallow surface of the baffle, a contact area is formed instead of a contact point. A clean cut will be achieved in the area of ​​contact. However, this incomplete partial contact will produce a reaction force so that the rest of the blade edge does not interact with the baffle surface, resulting in an uneven cut. Failure mode A shows the importance of keeping the baffle surface and the razor blade edge parallel (even if the razor blade and baffle surface are very straight). Failure mode A is almost always due to manufacturing inaccuracies and / or assembly errors of the connecting rod.

[0013] On the other hand, failure mode B describes the incomplete contact caused by the fine-toothed razor blade, while failure mode C represents the situation where the uneven surface of the baffle contacts a very straight blade edge.

[0014] In failure modes B and C, the cutting force is only applied to the contact area, while the non-contact area does not generate cutting force, resulting in an uneven cut. Failure mode A is related to manufacturing inaccuracies and misalignment of the connecting rod assembly, even if the blade edge and the baffle surface are assumed to be ideal. Failure modes B and C are caused by manufacturing inaccuracies of the cutter, which cannot be eliminated in theory and are related to the manufacturing method in addition to mechanical accuracy. Please note that the gap of incomplete contact depicted in the above failure modes is exaggerated for demonstration purposes. In fact, the gap size that will cause cutting failure is usually less than 100 microns.

[0015] In the actual application of side-bite punches, these three failure modes coexist during cutting. The root cause of failure is due to the non-parallel linkage mechanism that mounts the razor and the baffle, and the non-smooth surface and wavy edge profile of the baffle and blade edges. In the process of manufacturing the linkage, razor blade and baffle, certain strict tolerances must be met. Although it is very impractical to require very strict tolerances in the manufacturing and assembly processes. In order to overcome this practical difficulty, a remedy that effectively reduces the above failure modes must be proposed, such as installing a semi-rigid pad on the baffle. This pad must have an appropriate surface hardness. A pad with too low hardness may cause cutting failure because the tissue may block the cut instead of being cut along the cutting line. However, a pad with too high hardness will result in an incomplete contact area during cutting because the hard pad will prevent the initial area of ​​contact with the blade from expanding further, making it impossible to produce sufficient contact engagement required for a clean cut.

[0016] Typical side bite cutter and baffle designs include: Figure 3a , 3b , 4a, 4b. The cutter includes a U-shaped razor blade, a blade holder and a locking mechanism, as shown in FIG. Figure 3a Exploded view and Figure 3b The U-shaped razor blades are pre-formed and have different sizes to achieve different hole sizes in the blood vessel wall. The baffle includes a fixed base and a semi-rigid pad mounted thereon, and an adjustable base mechanism, such as Figure 4a , 4b As shown. This pair of cutting modules (such as the cutter and the baffle) can be installed on a connecting rod structure that can generate and transmit force, and the cutter, the baffle and the connecting rod structure will form a one-side biting blood vessel perforator. Furthermore, the connecting rod structure will be referred to as an operator later.

[0017] The operator required to implement the side-bite punch is a four-link and single-pivot mechanism (but not limited to this), such as Figure 5 , 6 shown. Figure 5 In the invention, the four-bar linkage comprises two crossbars on which the razor blades and the baffle are mounted, and the two crossbars are connected in a parallel manner. By rotating the two connecting rods connected to the crossbars, the distance between the razor blade edge and the baffle surface is gradually reduced to zero, so that the razor blade edge and the baffle surface come into contact. The razor blade edge is semicircular or any curved shape and has open two end points. During the cutting process, the razor blade and the baffle will approach each other, forming the so-called contact line. The normal stress generated along the contact line is usually large enough to cut the tissue compressed along the contact line.

[0018] like Fig. 9 ,10 As shown, the contact line between the razor edge and the baffle can also be achieved by a single pivot mechanism, in which two crossbars are connected in a specific scissor-like design. During cutting, the contact line between the razor edge and the baffle will be formed when the pivot crossbar is in the closed position. According to the same side bite principle as the four-bar punch, the tissue will be separated at this time.

[0019] Depending on the characteristics of the linkage mechanism designed in each operator, the required force amplification can be achieved. Figure 5 , 6 The four-bar linkage or Fig. 9 , 10 The single pivot mechanism in the paper is assumed to be an ideal rigid body. However, in reality, the combined beam-shaped crossbar is not a perfect rigid body under stress. When designing and manufacturing parts, different materials and crossbar structures (solid round rods, thin-walled I-beams, U-beams, etc.) will produce different degrees of bending. The bending deformation of the crossbar will cause the contact force to be absorbed by the deformation of the structure according to the elasticity of the material, resulting in uneven or even insufficient distribution of the cutting force along the contact line, or causing the contact line to be misaligned and unable to achieve a neat cut on the target tissue.

[0020] The best embodiment of the present invention is achieved by Figure 5 The side-biting blood vessel perforator shown in the figure is composed of a cutter crossbar, a baffle crossbar and an operator connecting the two crossbars. The baffle crossbar is rigidly assembled on a pistol-shaped base, which will be held in the palm of the user. There are two shorter connecting rods responsible for connecting the cutter crossbar and the baffle crossbar to form a parallelogram four-bar linkage to facilitate the cutting action. A trigger rod slidably connected to the cutter crossbar can apply force to rotate the two connecting rods through a pivot in the groove, so that the cutter crossbar can perform a translational movement relative to the baffle crossbar, such as Figure 7 , 8 When the blade edge and the baffle plane meet, the forward translation of the cutter crossbar stops and a contact line is formed between the two.

[0021] When the contact line is formed, the rotation of the connecting rod will stop, so that the gripping force of the hand on the four-bar linkage will be converted into a cutting force. After the contact line is formed and the cutting force is generated, the cutting of the tissue can be achieved. The semi-rigid pad on the baffle will completely receive the razor blade and reduce the influence of errors in manufacturing and assembly. Generally speaking, by providing the pad with appropriate hardness, the razor blade will cut through the compressed tissue and even reach a certain depth of the semi-rigid pad. Therefore, when the user completes the cutting and presses the trigger to keep it in the closed position, the tissue cut from the blood vessel will be retained in the space surrounded by the razor blade and the baffle. Through the present invention, it is possible to neatly punch holes in the blood vessel, and the cut tissue can be safely removed from the human body.

[0022] Reference Fig. 9 , 10 Another embodiment of the present invention is a scissor-like side-biting blood vessel punch that is connected by a single pivot to a cutter crossbar and a baffle crossbar. The two crossbars are installed in such a way that when the gripping force is applied, the two crossbars will enter a closed position for cutting, and a contact line will be formed between the razor blade and the baffle surface. Compared with a four-bar punch, a single-pivot punch is more susceptible to manufacturing and assembly errors. Errors are easily magnified at positions farther from the pivot. When this scissor-like punch is used for tissue separation, the initial contact point or segment formed usually falls in the area closer to the pivot, that is, at the two tail ends of the U-shaped razor blade.

[0023] For the razor portion away from the pivot, especially the razor in the semicircular portion, the gap between the razor edge and the baffle surface will be larger as the distance from the pivot becomes farther. This often results in incomplete cutting of the razor blade in the semicircular portion away from the pivot. Very precise parts manufacturing and assembly methods are required to achieve neat tissue cutting. In order to reduce the common failure of incomplete or irregular cutting during contact line formation, the baffle must be an adjustable design, specifically, a positioning mechanism is provided for the surface of the baffle. During the assembly of the punch, the cutter crossbar and the baffle crossbar are first installed on the pivot, and then the two crossbars are adjusted to the closed position, and the initial contact point or initial contact segment is established at the same time. By adjusting the positioning of the baffle surface, the cutting engagement of the entire blade edge and the baffle can be maximized to form an approximate required complete contact line. After installing a semi-rigid pad that can reduce errors, the expected neat cutting can usually be achieved.

[0024] U-shaped razor blades with different radii of curvature can also be specified to create holes of different sizes in the blood vessel. Oval blades can also be customized to meet the needs of specific artificial blood vessel connections. In clinical end-to-side anastomosis, the connected blood vessels or artificial blood vessels will have different cross-sectional shapes depending on the different angles of connection of the artificial blood vessel to the host. The present invention can achieve the goal of this anastomosis by providing a set of pre-formed blades, the shape of which is designed for the projected shape and size of the suture area.

[0025] In the process of surgical perforation, it is most important to keep hemostasis. The side bite-off punch of the present invention can ideally cooperate with the existing partial clamp-stop tool. Fig.11 , 12The overall application of the side-bite-off punch and the partial clamp-off hemostat is demonstrated. Before perforating a blood vessel, first, a portion of the target blood vessel is clamped to prepare an isolation area for perforation. In this isolation area, the blood vessel wall becomes flat, and the blood flow of the artery is blocked and cannot enter this isolation area. At this time, the side-bite-off punch can act on this area, and the razor blade will perform a cutting action at a limited distance from the boundary of the clamping area ( Fig.12 This combined tool provides highly reliable hemostasis during and after the currently designed perforation procedure. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The cutting efficiency, mechanical principles and other objects, features and advantages of the present invention can be understood by referring to the following description of the accompanying drawings:

[0027] Figure 1a The side bite-off punch includes a U-shaped razor cutter and a baffle base for generating a positive force during cutting.

[0028] Figure 1b is a cross-sectional view of a razor blade engaged in tissue separation, and is the normal cutting stress generated by the applied force F divided by the blade edge area A.

[0029] Figure 2a Illustrated is failure mode A of a side bite-off punch, where the razor edge and the baffle surface are not aligned due to errors in the manufacture or assembly of the parts by the operator, resulting in incomplete contact of the cutting line and tissue cutting.

[0030] Figure 2b The figure shows failure mode B of the side bite punch, which refers to the wavy shape of the razor edge due to manufacturing errors, resulting in incomplete cutting line contact and tissue cutting.

[0031] Figure 2c The figure shows the failure mode C of the side bite-off punch, which refers to the uneven surface of the baffle plate due to manufacturing errors, resulting in incomplete contact of the cutting line and tissue cutting.

[0032] Figure 3a An exploded view of a representative side bite cutter design consisting of a U-shaped razor blade, blade holder, and locking mechanism.

[0033] Figure 3b A cross-sectional view of a representative side bite cutter design consisting of a U-shaped razor blade, blade holder, and locking mechanism.

[0034] Figure 4ais an exploded view of a representative baffle design consisting of a fixed base, semi-rigid pad, and adjustable pad platform.

[0035] Figure 4b is a cross-sectional view of a representative baffle design consisting of a fixed base, semi-rigid pad, and adjustable pad platform.

[0036] Figure 5 It is an exploded view of a preferred embodiment of a four-bar type side-bite hole punch.

[0037] Figure 6 It is a cross-sectional view of a preferred embodiment of a four-bar type side-bite punch.

[0038] Figure 7 It is a three-dimensional view of a four-bar type side-bite-off hole punch in an open position ready for use.

[0039] Figure 8 It is a stereoscopic view of a four-bar side bite-off punch in a closed position and having completed a side bite-off punching action.

[0040] Fig. 9 It is an exploded view of a single-pivot side-bite hole punch according to another embodiment.

[0041] Fig.10 It is a cross-sectional view of another embodiment of a single-pivot type side-bite punch.

[0042] Fig.11 The invention is a stereoscopic view of the side-biting-off puncher and the partial-clamping hemostatic forceps used in combination to punch a hole on a blood vessel wall to achieve hemostasis.

[0043] Fig.12 It is shown that a defined distance is created between the hemostatic area and the cutting line by clamping a portion of the blood vessel. DETAILED DESCRIPTION

[0044] refer to Figure 5 and Figure 6 The four-link side-biting blood vessel punch is composed of a razor cutter 10, a baffle 20, a cutter crossbar 30, a baffle crossbar 40, a pair of connecting rods 50 and a handle 60. The razor cutter can be further decomposed into a U-shaped razor blade 11, a blade holder 12 and a locking cover 13. Figure 3a and Figure 3bAs described in detail, the blade holder 12 is locked on the razor cutter 10 by means of a fixing screw 14, and the razor blade 11 is pressed against the inner flange of the blade holder 12 by means of a locking cover 13. During the installation of the razor blade 11, the back of the razor blade 11 first contacts the inner flange of the blade holder 12, and then the side wall of the razor blade 11 is pressed and shaped by the locking cover 13, and then the locking cover 13 is fixed by means of two locking screws 15. The cutter 10 and the baffle 20 are in contact with blood, so they tend to be manufactured for single use to eliminate the possibility of infection. When the assembly is completed, the cutter 10 becomes an integral extension of the cutter crossbar 30, and a strict assembly tolerance is required to ensure that the edge of the razor blade 11 and the cutter crossbar 30 are parallel.

[0045] The baffle 20 comprises a base 21 and a semi-rigid pad 22 glued thereon. Figure 4a and Figure 4b 20 is shown in the figure. The base 21 and the fence 20 are connected by a locking screw 23, and three fixing screws 24 are further added to adjust the positioning of the fence surface to obtain the best contact line during cutting. Similar to the integration of the cutter 10 and the blade holder 12, the fence 20 and the fence crossbar 40 also require strict tolerances for alignment.

[0046] The baffle crossbar 40 is rigidly connected to the handle 60, while the cutter crossbar 30 has a first pivot 65 fixed by a first screw 66, so that it is slidably connected to the handle 60 through the first pivot 65. A pair of connecting rods 50, each having a short pin and two through holes 51 at both ends thereof, on which the cutter crossbar 30 and the baffle crossbar 40 are rotatably connected, forming a four-bar linkage. The rotational movement of the connecting rod is provided by two pairs of pivots 52 and their corresponding screws 53, and the cutter crossbar 30 and the baffle crossbar 40 are connected in a rotationally constrained manner.

[0047] Figure 7 and Figure 8 The four-bar linkage is shown in two states: an open position ready for use and a closed position for retraction after cutting. The four-bar linkage mechanism makes synchronous rotational motion through two connecting rods 50, so that the cutter crossbar 30 can make parallel translational motion with the baffle crossbar 40. The parallelism between the cutter crossbar 30 and the baffle crossbar 40 is the key to the effective side-bite punch to remove vascular tissue during surgery. The parameters affecting the parallelism include the position of the connecting rod 50, the cutter crossbar 30 and the pivot hole drilled on the baffle crossbar 40, the matching tolerance of the connecting rod 50 and the parts connected in rotation, the cutter crossbar 30 and the baffle crossbar 40, and the rigidity of the cutter crossbar 30 and the baffle crossbar 40 when subjected to the cutting force generated by the hand-held device 62 holding the trigger 61 toward the handle 60.

[0048] For the cutter crossbar 30 and the baffle crossbar 40, a U-shaped beam structure is optimal because such a thin-walled structure can achieve maximum bending stiffness of the crossbar rigidity with a lighter weight. The trigger 61 is rotatably mounted on the handle 60 through a second pivot 63 and a second screw 64 corresponding thereto, forming a mechanism for applying a cutting force to the side bite punch and causing the cutter crossbar 30 to perform translational movement. The cutter crossbar 30 is connected to the groove of the trigger 61 by a first pivot 65 and a first screw 66, and forms a pivot-in-groove relationship with the end portion of the trigger 61, wherein a groove is provided to accommodate the first pivot 65.

[0049] Thus, the cutter bar 30 can be pushed forward from the upright position to the closed position, and vice versa, from the closed position back to the upright position. The force required for the forward movement is provided by the hand grip, and the backward movement is provided by the recoil force generated by a pair of leaf springs 67, whose spring legs are fixed to the hand-held device 62 and the trigger 61 by screws 68 respectively. When the trigger 61 moves in a circle around the second pivot 63, the end groove of the trigger 61 guides the cutter bar 30 to move forward and backward and slide the first pivot 65 in the groove, and then the connecting rod 50 rotates and drives the cutter bar to move upward or downward accordingly. The hand gripping of the trigger 61 towards the hand-held device 62 initiates the cutting action and drives the cutter bar 30 downward until the edge of the razor blade 11 falls on the surface of the baffle to cut the compressed tissue under the contact line. After the cutting is completed, the user keeps the present invention in the closed position, which can ensure that the cut vascular tissue remains in the space defined by the inner side of the razor blade 11 and the baffle 20. Therefore, after the present invention is removed from the patient's body, the tissue can be safely removed.

[0050] Another embodiment of the present invention - a single pivot type mechanism, such as Fig. 9 and Fig.10 As shown. The single-pivot side-bite punch comprises a razor cutter 70 and a baffle 80 which is preferably adjustable, a cutter crossbar 90, a baffle crossbar 100, a pair of leaf springs 101, a pivot 102 and its pivot screw 103. The razor cutter 70 is composed of a razor blade 71, a blade holder 72, a locking cover 73, a locking screw 74 and two fixing screws 75, as in the design of the aforementioned four-bar side-bite punch. The razor cutter 70 is rigidly mounted at the end of the cutter crossbar, and the baffle 80 is also mounted on the baffle crossbar 100. The cutter crossbar 90 and the baffle crossbar 100 are locked together by the pivot 102 and the pivot screw 103 to form a scissor-like structure, so that the gripping force can be amplified and transmitted to the edge of the razor blade. This single pivot side bite punch aligns the contact line of the blade edge with the fence surface when the punch is brought to the closed position for cutting.

[0051] The design of the adjustable baffle 80 is similar to the baffle 20 in the aforementioned four-bar linkage configuration. For this adjustable baffle 80, the pad platform 82 is glued onto the semi-rigid pad 81 and is loosely mounted on the support base of the baffle 80 from the outside by the locking screw 83 so that the positioning of the pad can be adjusted. Moreover, the adjustment method of the pad positioning is not limited to this. There are also three fixing screws 84, which form the three vertices of a triangle and are locked on the base of the baffle 80 to adjust the positioning of the baffle 80 surface. By individually adjusting the locking depth of the three fixing screws 84 and the locking screw 83, the contact line of the cutting can be repositioned so that the razor edge and the semi-rigid pad 81 can have complete contact, thereby improving the cutting efficiency.

[0052] During surgical procedures, ensuring hemostasis is of utmost importance during the perforation of large blood vessels. Partial clamp hemostats are usually used to achieve partial blood flow blockage in arteries or veins. The present invention of the punch can be easily used with those clinically proven partial clamp hemostats to prevent bleeding, both during and after the perforation. Fig.11 and Fig.12 The combined use of the present invention and the partial clamp hemostat is illustrated in FIG. First, the partial clamp hemostat is used to create an area to isolate the blood flow. Then, a side bite-off punch is used to cut off part of the tissue in the hemostatic area. The cutting line is as shown in FIG. Fig.12 As shown, there is still enough distance between the clamped hemostat and the puncture. When the partial clamp hemostat is locked to the fixed point, bleeding problems can be eliminated, and end-to-side anastomosis can be safely performed by suturing the end of the artificial blood vessel and around the opening.

[0053] Existing vascular punches (anvil-in-a-tube-cutter type) generate shear force based on the linear or threaded overlap of the anvil and its cutting tube, which is well known to vascular surgeons. In fact, tissue separation can only be achieved when the hole diameter is less than 6 mm. If a larger hole is to be made in the blood vessel, the force required far exceeds the limit of human grip strength, and it is usually difficult to maintain hemostasis. In actual application, surgeons usually need to repeat the side bite-off action around the small hole several times to achieve the required large hole diameter. As a result, the workload is increased, but the quality of the hole is not necessarily guaranteed. The present invention proposes a side bite-off punch design based on a completely different positive force tissue separation principle, which can be easily operated with a partial clamp hemostat to maintain hemostasis during and after the hole. Although the present invention introduces and describes two embodiments, it should be understood that those skilled in the art can design different modifications or equivalents without violating the spirit and scope defined by the appended claims of the present invention.

Claims

1. A blood vessel puncher, comprising: A sharp razor-like cutter having a U-shaped razor blade mounted on a blade holder; an adjustable baffle, comprising a pad platform provided with a surface positioning mechanism, a U-shaped rigid base positioned on the pad platform, and a semi-rigid pad disposed on the U-shaped rigid base, wherein the semi-rigid pad abuts against the U-shaped razor blade when the razor-shaped cutter presses down the adjustable baffle, so that a contact line is formed between the edge of the U-shaped razor blade and the inner wall of the U-shaped rigid base; An operator, comprising: a cutter crossbar, wherein the cutter assembly is mounted on the front end of the cutter crossbar so that the edge of the U-shaped razor blade is parallel to the cutter crossbar; A baffle crossbar, wherein the baffle assembly is disposed at the front end of the baffle crossbar; a handheld device connected to the baffle crossbar; and A trigger, pivotally connected to the handheld device and slidably connected to the cutter crossbar; The surface positioning mechanism includes a locking screw locked from the inside of the adjustable baffle and three fixing screws locked from the outside; the three fixing screws are individually adjusted to form a complete contact line between the edge of the U-shaped razor blade and the surface of the semi-rigid pad.

2. The blood vessel punch according to claim 1, wherein the cutter cross bar and the baffle cross bar are rotatably hinged to form a four-bar parallelogram linkage mechanism, so that the cutter cross bar can form a contact line between the edge of the U-shaped razor blade and the baffle surface on the baffle cross bar; and a spring assembly is connected between the handheld device and the trigger.

3. The blood vessel punch according to claim 2, wherein a groove is provided at the end of the trigger for accommodating the pivot of the cutter crossbar, wherein the pivot of the cutter crossbar is allowed to move linearly in the groove of the trigger, and the finger applying force and a spring assembly together put the trigger in a cocked position ready for use.

4. A blood vessel puncher, comprising: A sharp razor-like cutter having a U-shaped razor blade mounted on a blade holder; an adjustable baffle, comprising a pad platform provided with a surface positioning mechanism, a U-shaped rigid base positioned on the pad platform, and a semi-rigid pad disposed on the U-shaped rigid base, wherein the semi-rigid pad abuts against the U-shaped razor blade when the razor-shaped cutter presses down the adjustable baffle, so that a contact line is formed between the edge of the U-shaped razor blade and the inner wall of the U-shaped rigid base; An operator, comprising: a cutter crossbar, wherein the cutter assembly is mounted on the front end of the cutter crossbar so that the edge of the U-shaped razor blade is parallel to the cutter crossbar; A baffle crossbar, wherein the baffle assembly is disposed at the front end of the baffle crossbar; The cutter crossbar and the baffle crossbar are rotatably hinged to form a scissor-shaped link mechanism, so that the cutter crossbar is brought onto the baffle crossbar to form a contact line between the edge of the U-shaped razor blade and the baffle surface at the ends of the cutter crossbar and the baffle crossbar; and a spring assembly is connected to the proximal ends of the cutter crossbar and the baffle crossbar. The surface positioning mechanism includes a locking screw locked from the inside of the adjustable baffle and three fixing screws locked from the outside; the three fixing screws are individually adjusted to form a complete contact line between the edge of the U-shaped razor blade and the surface of the semi-rigid pad.

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