Protective structure and indwelling needle

Abstract

The utility model discloses a protective structure and indwelling needle, protective structure includes: elastic part, is set up with the through -hole of the puncture needle of indwelling needle's crossing on it, the aperture of through -hole is less than the maximum outer diameter of puncture needle upper limit department, and elastic part is equipped with at least one protective sheet towards needle tip one end, protective layer is connected with elastic part and is at least covered in the circumferential side of elastic part, and protective layer can deform with elastic part to cover needle tip with elastic part jointly after the retreat of puncture needle. The protective structure can effectively avoid the blood residual infection risk and the positive pressure spatter problem, and the security and the operation convenience of clinical use are significantly improved.

Description

Technical Field

[0001] This utility model relates to the field of medical devices, and in particular to a protective structure and an indwelling needle. Background Technology

[0002] Indwelling intravenous catheters are commonly used vascular drug delivery devices in clinical practice. Due to their advantages such as reducing repeated punctures and improving treatment efficiency, they are widely used in infusion, blood transfusion, and drug administration scenarios. Among existing technologies, open-type indwelling catheters are one of the mainstream types. Their typical structure includes a puncture needle, catheter, catheter hub, needle hub, and anti-puncture component. The anti-puncture component often uses an elastic spring structure (such as a figure-eight shaped metal spring) to wrap around the needle tip after puncture to avoid the risk of needlestick injury.

[0003] During the procedure, once the puncture needle penetrates the blood vessel wall and blood return is observed in the needle hub's blood return chamber, medical staff need to press on the blood vessel and withdraw the puncture needle. At this time, the elastic spring structure, due to the restriction of the catheter hub's inner lumen, does not initially move synchronously with the puncture needle; when the needle tip is withdrawn to the spring opening position, the spring closes under its own elastic force, wrapping around the needle tip and continuing to withdraw with the puncture needle, ultimately achieving the anti-needle puncture function.

[0004] However, existing open-type indwelling needles still present the following problems in clinical use: The existing elastic spring structure is an open structure, meaning that even after the needle tip is retracted and covered, a tiny gap remains exposed, posing a risk of infection from residual blood at the needle tip. Furthermore, due to the positive pressure within the blood vessel, blood sprays from the needle tip to the needle hub during puncture, easily creating a closed space within the needle hub and forming a positive pressure cavity. After needle withdrawal, a small amount of blood remaining in the needle tube may splash out from the open gap on the side of the elastic spring structure under this positive pressure, leading to occupational exposure for healthcare workers or environmental contamination, increasing the difficulty of infection control. Summary of the Invention

[0005] To overcome the deficiencies in the prior art, this utility model provides a protective structure and indwelling needle. The synergistic effect of the elastic element and the protective layer covers the needle tip and intercepts leaking blood. Combined with the breathable element, it balances the pressure of the blood return chamber, effectively avoiding the risk of infection from residual blood and the problem of positive pressure splashing, significantly improving the safety and ease of operation in clinical use.

[0006] To achieve the above objectives, the technical solution adopted by this utility model is as follows:

[0007] Firstly, a protective structure for an indwelling needle includes:

[0008] An elastic element has a through hole for the puncture needle of the indwelling needle to pass through. The diameter of the through hole is smaller than the maximum outer diameter of the upper limit portion of the puncture needle. The elastic element has at least one protective plate at the end facing the needle tip.

[0009] A protective layer is connected to the elastic element and at least covers the periphery of the elastic element. The protective layer can deform with the elastic element so that it, together with the elastic element, covers the needle tip after the puncture needle is retracted.

[0010] This protective structure uses a through-hole in an elastic element to engage with a limiting part on the indwelling needle. When the needle retracts to the point where the limiting part and the inner wall of the through-hole form a limit, the protective sheet of the elastic element automatically retracts and covers the needle tip. Simultaneously, the protective layer connects to the elastic element and deforms synchronously with it, both together covering the needle tip to form a closed space. Through the synergistic effect of the physical covering of the elastic element and the outer periphery of the protective layer, the leakage channel of residual blood at the needle tip can be blocked, thereby reducing the occupational exposure risk for medical personnel.

[0011] Optionally, the protective layer is a flexible sheet structure, including a protective circumferential portion surrounding the outer periphery of the elastic element and a protective bottom portion located on the side of the elastic element opposite to the protective sheet. The protective circumferential portion and the protective bottom portion enclose a receiving space. By enclosing the receiving space with the protective circumferential portion and the protective bottom portion, the open areas of the outer periphery and bottom of the elastic element can be covered, preventing blood from leaking further from the open areas of the elastic element after leakage from the gap between the needle tip and the protective sheet, thus avoiding occupational exposure of medical personnel or environmental contamination, and increasing the difficulty of infection control.

[0012] Optionally, the edge of the protective circumferential portion is connected to the protective sheet, and the volume of the accommodating space is larger than the volume of the elastic element, allowing the protective layer to have deformation allowance. Through the connection between the edge of the protective circumferential portion and the protective sheet, the protective layer and the protective sheet can move in tandem. When the elastic element causes the protective sheet to retract, the protective circumferential portion can simultaneously tighten to conform to the movement trajectory of the protective sheet. Simultaneously, the volume allowance of the accommodating space provides sufficient deformation buffer for the protective layer, helping to reduce the risk of wrinkles or breakage caused by excessive stretching of the protective layer during changes in the elastic element's state, thereby improving the sealing integrity of the area around the needle tip.

[0013] Optionally, the thickness of the protective layer is 0.1 mm to 0.5 mm. This thickness range helps to balance the flexibility and structural strength of the protective layer. The lower limit of 0.1 mm helps the protective layer achieve micron-level conformal deformation with the elastic element; the upper limit of 0.5 mm can enhance the physical barrier against blood splashes, while also helping to avoid excessively occupying the internal space of the catheter due to excessive thickness, thereby increasing the volume of the catheter.

[0014] Optionally, the elastic element includes a base and at least two elastic arms connected to the base. The through hole is opened in the base. One end of each elastic arm is connected to the base, and the other end extends toward the needle tip and is provided with the protective plate. When the puncture needle is retracted to the limiting part and forms a limiting fit with the inner wall of the through hole, the elastic arm can retract toward the axis of the puncture needle, so that the protective plate covers the needle tip.

[0015] An indwelling needle, comprising:

[0016] Conduit fittings;

[0017] The needle hub assembly is detachably connected to the catheter, and the needle hub assembly has a blood return chamber inside;

[0018] The puncture needle has a needle tip at one end that is movably inserted through the catheter, and the other end is connected to the needle hub assembly and communicates with the blood return chamber. A limiting part is provided on the side wall of the puncture needle near the needle tip.

[0019] An elastic element is disposed within the catheter assembly and has a through hole through which the puncture needle passes. The diameter of the through hole is smaller than the maximum outer diameter of the limiting portion. At least one protective plate is provided on the end of the elastic element facing the needle tip. The elastic element is configured such that when the puncture needle is in the puncture position, the protective plate is located on the side of the puncture needle; when the puncture needle is retracted to the limiting portion and forms a limiting fit with the inner wall of the through hole, the protective plate can cover the needle tip.

[0020] A protective layer is connected to the elastic element and at least covers the periphery of the elastic element. The protective layer can deform synchronously with the elastic element so that it, together with the elastic element, covers the needle tip after the puncture needle is retracted.

[0021] Optionally, the needle hub assembly includes a needle hub body and at least one venting element. The venting element is disposed on the needle hub body and communicates with the blood return chamber to achieve gas exchange between the blood return chamber and the external environment. By setting up a first venting element and a second venting element to form a dual venting guarantee, the problem of positive pressure accumulation in the blood return chamber caused by blockage or closure of a single venting path can be effectively prevented. The synergistic effect of the two elements can balance the increase in intraluminal pressure caused by positive vascular pressure, avoid the risk of blood splashing caused by venting failure, and maintain the timeliness and clarity of blood return observation, thereby improving the safety and reliability of clinical operations.

[0022] Optionally, the breathable component is a sintered PE plug or an expanded polytetrafluoroethylene breathable membrane.

[0023] Due to the application of the above technical solution, this utility model has the following advantages compared with the prior art:

[0024] 1. The protective sheet of the elastic element first achieves physical coverage of the needle tip. The protective layer covers the outer periphery and bottom of the elastic element through a flexible sheet structure, forming a secondary protection of "initial coverage + leakage interception". This intercepts blood leakage from the gaps in the protective sheet, solves the problem of blood spillage caused by the side opening of the traditional open elastic sheet structure, and reduces the occupational exposure risk of medical staff.

[0025] 2. The first and second venting components of the needle hub assembly achieve bidirectional gas flow through a dual path at the end of the blood return chamber and the side wall (gas inside the chamber is discharged under positive pressure, and external gas is introduced under negative pressure). Combined with the material design with liquid barrier properties, it can prevent abnormal pressure caused by blockage of a single channel and avoid blood leakage, ensuring stable pressure inside the chamber during needle withdrawal and reducing the possibility of blood splashing from the source.

[0026] 3. The protective layer, with a thickness ranging from 0.1mm to 0.5mm, balances flexibility and structural strength, allowing it to deform synchronously with the elastic component without occupying excessive space within the catheter lumen. The venting component uses a sintered PE plug or expanded polytetrafluoroethylene (ePTFE) venting membrane, with material properties precisely matched to gas exchange requirements, enhancing long-term stability. Simultaneously, the dual-protection design does not add any steps to the procedure or affect the smoothness of needle retraction, meeting the needs of rapid clinical procedures.

[0027] To make the above and other objects, features and advantages of this utility model more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0028] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0029] Figure 1 This is a partial schematic diagram of the protective structure in an embodiment of this utility model;

[0030] Figure 2 This is a schematic cross-sectional view of the indwelling needle puncture position in an embodiment of this utility model;

[0031] Figure 3 This is a side view of the indwelling needle retraction position in an embodiment of this utility model;

[0032] Figure 4 This is a schematic diagram of the puncture needle structure in an embodiment of this utility model;

[0033] Figure 5 This is a schematic diagram of the elastic element structure in an embodiment of this utility model;

[0034] Figure 6 This is a schematic diagram of the state of the puncture needle and the elastic element at the puncture position in an embodiment of this utility model;

[0035] Figure 7 This is a schematic diagram of the state of the puncture needle and elastic element in the retracted position in an embodiment of this utility model.

[0036] The reference numerals in the above figures are as follows: 1. Puncture needle; 11. Limiting part; 12. Needle tip; 2. Elastic element; 21. Base; 22. First through hole; 23. First elastic arm; 24. Second elastic arm; 25. Protective plate; 3. Protective layer; 31. Protective circumferential part; 32. Protective bottom; 4. Catheter component; 41. Catheter; 42. Catheter seat; 51. Needle seat; 52. Blood return chamber; 53. First ventilator; 54. Second ventilator. Detailed Implementation

[0037] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0038] Example 1: See Figure 1 As shown, a protective structure for indwelling needles includes an elastic element 2 for being fitted onto a puncture needle 1, and a protective layer 3 covering the outside of the elastic element 2. The protective layer 3 covers at least the periphery of the elastic element 2, and the protective layer 3 can deform synchronously with the elastic element 2 so that it, together with the elastic element 2, covers the needle tip 12 after the puncture needle 1 is retracted.

[0039] See Figure 4As shown, the puncture needle 1 is cylindrical in shape, with an axially extending blood return path inside. One end of the puncture needle 1 is machined into a needle tip 12 for vascular puncture. A limiting part 11 is provided on the side wall near the needle tip 12. The limiting part 11 is used to cooperate with the elastic element 2 to cover the needle tip 12 and prevent the needle tip 12 from puncturing medical personnel. The limiting part 11 can be a protrusion, and its specific shape can be designed in various forms according to clinical needs, such as an annular strip continuously distributed around the outer periphery of the puncture needle 1, or a long strip extending along the axial direction of the puncture needle 1. In an optional embodiment, the limiting part 11 is a long strip, and there are two of them. The two long strips are symmetrically arranged on both sides of the side wall of the puncture needle 1. The symmetrical layout ensures that the elastic element 2 is subjected to balanced force during the retraction of the puncture needle 1, avoiding the deflection of the protective plate 25 due to unilateral limiting. In a preferred embodiment, the outer surface of the strip facing away from the puncture needle 1 is curved. Specifically, when viewed along the axial direction of the puncture needle 1, from the end furthest from the needle tip 12 to the end closest to the needle tip 12, the curved surface exhibits a gradual thickening followed by thinning. That is, the thickness gradually increases from the initial end to the middle maximum thickness point, and then smoothly transitions to a thinner state towards the end. This curved surface guides the gradual application of force, reducing the feeling of jamming during the retraction of the puncture needle 1 and improving the synchronicity and stability of the retraction action of the elastic element 2 protective sheet 25.

[0040] See Figure 5 As shown, the elastic element 2 adopts an integral metal sheet structure, including a base 21, elastic arms, and a protective sheet 25. A first through hole 22 for the puncture needle 1 to pass through axially is provided in the middle of the base 21. A first side and a second side are provided oppositely along the width direction of the base 21, and a first end and a second end are provided oppositely along the length direction of the base 21. On the upper surface of the base 21, a first elastic arm 23 is provided at the first end of the first side, and a second elastic arm 24 is provided at the second end of the second side, with the two arms diagonally symmetrically distributed. The first elastic arm 23 extends upward from the surface of the base 21 and then tilts towards the second side, while the second elastic arm 24 extends upward simultaneously and then tilts towards the first side, forming a separate "X"-shaped structure with their apexes in a mutually distant state.

[0041] See Figure 5 As shown, each elastic arm has a protective plate 25 at its top. One end of the protective plate 25 is fixed to the elastic arm, and the other end extends obliquely upwards towards the center line of the base 21. The two protective plates 25 extend in opposite directions, and their free ends are separated by the puncture needle 1 when the puncture needle 1 is in the puncture position, allowing the puncture needle 1 to move. When the puncture needle 1 retracts to the limiting part 11 and forms a limiting fit with the inner wall of the first through hole 22, the elastic arm drives the protective plates 25 to retract in the axial direction, and the free ends abut against each other to form a wrap. See also Figure 6 , 7As shown, in the structural space, a vertical channel is formed between the two elastic arms, and a variable-diameter converging channel is formed between the two protective plates 25. The two are axially connected and coaxial with the first through hole 22 of the base 21, together forming the moving path of the puncture needle 1.

[0042] The one-piece molding design gives the elastic element 2 both structural stability and deformation flexibility. The metal material ensures that the protective plate 25 can still accurately return to its original position after multiple deformations. The "X"-shaped elastic arm layout improves the synchronicity of the closing action through symmetrical force application, effectively avoiding the risk of needle tip 12 exposure caused by unilateral deviation.

[0043] See Figure 1 As shown, in an optional embodiment, the protective layer 3 is made of a flexible sheet material (such as PE film, nylon film, or heat shrink tubing), forming a cylindrical structure that surrounds the elastic element 2. The two ends in the length direction are heat-fused together, and the lower end in the width direction is fixedly connected to the edge of the base 21, while the upper end is connected to the outer wall of the protective sheet 25, thereby completely sealing the open area around the elastic element 2 and preventing blood leakage from the side gaps. It is understood that the protective layer 3 is only connected by points or lines in the areas opposite to the protective sheet 25 and the base 21, thus achieving a sleeve-like fit over the elastic element 2. The protective layer 3 between the two protective sheets 25 is not connected, allowing it to retract synchronously when the protective sheets 25 are retracted.

[0044] In an optional embodiment, the protective layer 3 includes an integrally formed protective circumferential portion 31 and a protective bottom portion 32. The protective circumferential portion 31 surrounds the outer periphery of the elastic member 2, and the protective bottom portion 32 covers the side of the elastic member 2 facing away from the protective sheet 25, forming an accommodating space. The volume of this accommodating space is larger than the volume of the elastic member 2, providing sufficient deformation allowance for the protective layer 3. When the protective sheet 25 retracts with the retraction of the puncture needle 1, the protective circumferential portion 31 can synchronously contract in the axial direction to avoid wrinkles or cracks caused by excessive stretching; the protective bottom portion 32 covers the outer surface of the base 21. The top edge of the protective circumferential portion 31 is fixed to the outer wall of the protective sheet 25 by adhesive bonding or hot-melt welding to ensure that the protective sheet 25 drives the protective layer 3 to move synchronously during the retraction process. When the retraction of the puncture needle 1 triggers the closure of the protective sheet 25, the protective circumferential portion 31 tightens with the protective sheet 25, forming a dynamic sealing barrier outside the elastic member 2, effectively intercepting blood leaking from the gaps in the protective sheet 25, and together with the physical cover of the elastic member 2, constitutes a secondary protection system.

[0045] Understandably, the protective bottom 32 is provided with a second through hole coaxial with the first through hole 22 of the elastic element 2 base 21, and the diameter of the hole matches the diameter of the puncture needle 1. Although there is a through hole, the amount of blood remaining on the needle tip 12 is extremely small, and the protective circumferential part 31 and the protective bottom 32 have intercepted most of the splashed blood. The remaining trace amount of blood will be trapped by the double barrier structure of the elastic element 2 base 21 and the protective bottom 32, which can prevent it from leaking from the tiny gap between the through hole and the puncture needle 1.

[0046] In one optional embodiment, the thickness of the protective layer 3 is controlled within the range of 0.1 mm to 0.5 mm: the lower limit of 0.1 mm ensures that it can achieve micron-level conformal deformation with the elastic element 2, while the upper limit of 0.5 mm ensures the physical barrier against blood splashes. This thickness avoids occupying too much internal space of the catheter element 4 (preventing increased volume from affecting clinical operation) and balances flexibility and structural strength, meeting the requirements for long-term stability.

[0047] In an optional implementation, the protective layer 3 is made of a transparent material.

[0048] Secondly, see Figure 2 , 3 As shown, an indwelling needle includes:

[0049] The catheter fitting 4 includes a catheter seat 42 and a catheter 41 connected to the catheter seat 42;

[0050] The needle hub assembly is detachably connected to the catheter hub 42 (e.g., sleeved connection), and the needle hub assembly has a blood return chamber 52 inside;

[0051] The puncture needle 1 has a needle tip 12 at one end, which is movably inserted through the catheter 4 and can pass through the catheter 41. The other end is connected to the needle hub assembly and communicates with the blood return chamber 52. A limiting part 11 is provided on the side wall of the puncture needle 1 near the needle tip 12.

[0052] An elastic element 2 is disposed within the catheter 4, and has a through hole through which the puncture needle 1 passes. The diameter of the through hole is smaller than the maximum outer diameter of the limiting part 11. At least one protective plate 25 is provided on the end of the elastic element 2 facing the needle tip 12. The elastic element 2 is configured such that when the puncture needle 1 is in the puncture position, the protective plate 25 is located on the side of the puncture needle 1; when the puncture needle 1 is retracted to the point where the limiting part 11 forms a limiting fit with the inner wall of the through hole, the protective plate 25 can cover the needle tip 12.

[0053] The protective layer 3 is connected to the elastic element 2 and at least covers the periphery of the elastic element 2. The protective layer 3 can deform synchronously with the elastic element 2 so that it, together with the elastic element 2, covers the needle tip 12 after the puncture needle 1 is retracted.

[0054] In an optional embodiment, the needle hub assembly includes a needle hub 51 body and at least one venting element, the venting element being disposed on the needle hub 51 body and communicating with the blood return chamber 52 to realize gas exchange between the blood return chamber 52 and the external environment.

[0055] See Figure 2As shown, in a preferred embodiment, the venting element includes a first venting element 53 and a second venting element 54. The first venting element 53 is disposed at the end of the blood return chamber 52 opposite to the catheter 4, and the second venting element 54 is disposed on the side wall of the needle hub 51 body. Both the first venting element 53 and the second venting element 54 are configured to allow gas to pass through while preventing liquid from passing through. Optionally, multiple second venting elements 54 may be provided. The first venting element 53 and the second venting element 54 of the needle hub assembly achieve bidirectional gas flow through a dual path at the end and side wall of the blood return chamber 52 (gas inside the chamber is discharged under positive pressure, and external gas is introduced under negative pressure). Combined with the material design with liquid barrier properties, this not only prevents abnormal pressure caused by blockage of a single channel but also avoids blood leakage, ensuring stable pressure inside the chamber during needle withdrawal and reducing the possibility of blood splashing from the source.

[0056] In one optional embodiment, the breathable element is a sintered PE plug or an expanded polytetrafluoroethylene breathable membrane.

[0057] This utility model uses specific embodiments to illustrate the principle and implementation of the utility model. The above description of the embodiments is only for the purpose of helping to understand the method and core idea of ​​the utility model. At the same time, for those skilled in the art, there will be changes in the specific implementation and application scope based on the idea of ​​the utility model. Therefore, the content of this specification should not be construed as a limitation of the utility model.

Claims

1. A protective structure for a needle, comprising: include: An elastic element has a through hole for the puncture needle of the indwelling needle to pass through. The diameter of the through hole is smaller than the maximum outer diameter of the upper limit portion of the puncture needle. The elastic element has at least one protective plate at the end facing the needle tip. A protective layer is connected to the elastic element and at least covers the periphery of the elastic element. The protective layer can deform with the elastic element so that it, together with the elastic element, covers the needle tip after the puncture needle is retracted.

2. The containment structure of claim 1, wherein, The protective layer is a flexible sheet structure, including a protective circumferential portion surrounding the outer periphery of the elastic member and a protective bottom located on the side of the elastic member opposite to the protective sheet. The protective circumferential portion and the protective bottom enclose and form an accommodating space.

3. The containment structure of claim 2, wherein, The edge of the protective circumferential portion is connected to the protective sheet, and the volume of the accommodating space is larger than the volume of the elastic element, so that the protective layer has a deformation allowance.

4. The containment structure of claim 1, wherein, The thickness of the protective layer is 0.1mm to 0.5mm.

5. The containment structure of claim 1, wherein, The elastic element includes a base and at least two elastic arms connected to the base. The through hole is opened in the base. One end of each elastic arm is connected to the base, and the other end extends towards the needle tip and is provided with the protective plate. When the puncture needle is retracted to the limiting part and forms a limiting fit with the inner wall of the through hole, the elastic arm can retract towards the axis of the puncture needle, so that the protective plate covers the needle tip.

6. An indwelling needle comprising the protective structure according to any one of claims 1-5, characterized in that, include: Conduit fittings; The needle hub assembly is detachably connected to the catheter, and the needle hub assembly has a blood return chamber inside; The puncture needle has a needle tip at one end that is movably inserted through the catheter, and the other end is connected to the needle hub assembly and communicates with the blood return chamber. A limiting part is provided on the side wall of the puncture needle near the needle tip. An elastic element is disposed within the catheter assembly and has a through hole through which the puncture needle passes. The diameter of the through hole is smaller than the maximum outer diameter of the limiting portion. At least one protective plate is provided on the end of the elastic element facing the needle tip. The elastic element is configured such that when the puncture needle is in the puncture position, the protective plate is located on the side of the puncture needle; when the puncture needle is retracted to the limiting portion and forms a limiting fit with the inner wall of the through hole, the protective plate can cover the needle tip. A protective layer is connected to the elastic element and at least covers the periphery of the elastic element. The protective layer can deform synchronously with the elastic element so that it, together with the elastic element, covers the needle tip after the puncture needle is retracted.

7. The indwelling needle of claim 6 wherein, The needle hub assembly includes a needle hub body and at least one venting element. The venting element is disposed on the needle hub body and communicates with the blood return chamber to realize gas exchange between the blood return chamber and the external environment.

8. The indwelling needle according to claim 7, characterized in that, The venting element includes a first venting element and a second venting element. The first venting element is located at one end of the blood return chamber opposite to the catheter, and the second venting element is located on the side wall of the needle hub body. Both the first venting element and the second venting element are configured to allow gas to pass through while preventing liquid from passing through.

9. An indwelling needle according to claim 7 or 8, characterised in that, The breathable component is a sintered PE plug or an expanded polytetrafluoroethylene breathable membrane.

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