GB2507761A

GB2507761A - A device for introducing a medical element into a blood vessel

Info

Publication number: GB2507761A
Application number: GB201220134A
Authority: GB
Inventors: Manoj Srivastava
Original assignee: BARKING HAVERING AND REDBRIDGE UNIVERSITY HOSPITALS NAT HEALTH SERVICE TRUST
Current assignee: BARKING HAVERING AND REDBRIDGE UNIVERSITY HOSPITALS NAT HEALTH SERVICE TRUST
Priority date: 2012-11-08
Filing date: 2012-11-08
Publication date: 2014-05-14
Also published as: GB201220134D0; WO2014072690A1

Abstract

A device 2 for introducing a medical clement into a blood vessel is disclosed. It comprises a proximal body portion 4 connected to a distal body portion 6. The portions are connected in such a way as to allow them to switch between a first relative orientation 10 and a second relative orientation 14. When the distal body portion 6 has been inserted into the blood vessel, a medical element can be inserted into the blood vessel through the proximal body portion 4 in one axial direction 10 of the blood vessel when the proximal and distal body portions arc in the first relative orientation and in the other axial direction 14 of the blood vessel when the proximal and distal body portions arc in the second relative orientation. The medical element is preferably a catheter or a guide wire. Preferably the two portions 4, 6 are connected by a hinge and are rotatably engaged. Optionally, in the first orientation the proximal portion 4 is at a first angle relative to the distal portion 6 and, in the second orientation, the proximal portion 4 is at a second angle relative to the distal portion 6.

Description

A DEVICE FOR INTRODUCING A MEDICAL ELEMENT INTO A BLOOD VESSEL

The present invention relates to a device for introducing a medical element, for example a guidewire or catheter, into a blood vessel, in particular a device that allows the medical element to be inserted selectively in either or both of the two axial directions of the blood vessel.

Atherosclerosis Frequently occurs in difFerent parts of the body simultaneously, For example in the coronary vasculature and in a section of the peripheral vasculature, such as in a leg. The treatment may involve the introduction of a catheter into the vascular system, for example via the femoral artery. In order to simplify the intervention process and/or reduce stress on the patient, it is desirable to make only a single puncture in the femoral artery. However, it is challenging to introduce a catheter into the femoral artery in both of the two axial directions of the artery using a single puncture.

US 2012/0010563 Al discloses a bidirectional vascular introducer sheath which can be inserted into the patient and which allows a guide wire for a catheter to be inserted in both directions of an artery. However, the disclosed introducer is complex and bulky, leading to increased manufacturing expense and, possibly, risk of infection. Furthermore, the procedure for inserting and using the introducer is fundamentally different to procedures traditional unidirectional catheter insertion. Use of the introducer sheath of US 2012/0010563 Al thus requires a surgeon to learn new skills.

It is an object of the invention to address at least some of the problems with the prior art discussed above. In particular, it is an object of the invention to provide a device for introducing a medical element into a blood vessel that is of simple construction, cost effective to manufacture, easy for a surgeon to use and/or which minimizes a risk of infection.

According to an aspect of the invention, there is provided a device for introducing a medical element into a blood vessel of a human or animal body, comprising: a proximal body portion and a distal body portion, the proximal body portion being connected to the distal body portion in such a way as to allow switching of the relative orientation between the proximal and distal body portions between a first relative orientation and a second relative orientation, the device being configured such that: when the distal body portion has been inserted into the blood vessel, a medical element can be inserted into the blood vessel through the proximal body portion in one axial direction of the blood vessel when the proximal and distal body portions are in the first relative orientation and in the other axial direction of the blood vessel when the proximal and distal body portions are in the second relative orientation.

Thus, simply by manipulating the relative orientation between the proximal and distal body portions, a user is able to switch the direction of insertion of the medical element into the S blood vessel. This approach facilitates simple construction, thus minimizing manufacturing costs arid risk olinleclion.

In thc case wherc the relative oricntation is defined by the angle bctwccn the proximal and distal portions, use of the device will be similar to traditional "Seldinger" type catheter insertion methods. For example, the angle between the proximal body portion and the distal portion when the distal portion has been inserted completely into the blood vessel may be the same or similar to the angle that is typically made bctwccn a trocar and the guide wire during insertion of the guide wire by the Seldinger method. In contrast to traditional Seldinger devices, however, the present device provides the option of simultaneously inserting a guide wire (or other medical element) in the opposite direction of the blood vessel simply by switching the relative orientation of the proximal and distal body portions, without the need to make a second puncture through the skin.

In an embodiment, the first and second relatiye orientations are configured so that in use the angle at which the surgeon needs to maintain the proximal body portion relative to the skin in the region of thc puncturc is thc same in thc first and sccond rclative oricntations. In an example, the angle in the first relative orientation is 180 degrees minus the angle in the second relative orientation. In an example the angle in the first relative orientation is about 30 degrees and the angle in the second relative orientation is about 150 degrees. In this way, the experience for the surgcon is the same in both dcvicc oricntations.

In an embodiment, the proximal and distal body portions are connected together by a mechanical hinge. In an alternative embodiment, the proximal and distal body portions are formed integrally with each other, and the switching between the first and second relative orientations is achieved by bending the proximal body portion relative to the distal body portion.

In an embodiment, a flexible sheath is provided that surroullds the region of connection between the proximal and distal body portions. In an embodiment, a valve is provided in the flexible sheath to allow medical elements to be pushed out of the device into the blood vessel. In an cmbodimcnt, the valve is configured to prcvcnt or limit blood flow from the blood vcssel into the device, particularly when no medical element is present in the valve.

In an embodiment, the proximal and distal body portions comprise hyper-elastic material.

The hyper-elastic material may facilitate maintenance of an internal lumen of sufficient cross-sectional area through the operational bending range of the device, particularly when the proximal and distal body portions are formed as a single integral body.

S Embodiments of the invention will now be described, by way of example only, with rererence to We accompanying schematic drawings in which corresponding reference symbols indicate corresponding parts, and in which: Figure 1 depicts a device for introducing a medical element into a blood vessel according to an embodimeilt of the invention; Figure 2 is a schematic side sectional view showing the device of Figure 1 when inserted into the blood vesscl, with proximal and distal body portions of thc dcvice adopting a first relative orientation with respect to each other; Figure 3 is a schematic side sectional view of the device illustrated in Figures 1 and 2 in the case where the proximal and distal body portions adopt a second relative orientation with respect to each other; Figure 4 is a schematic "transparent" perspective view of elements of the proximal and distal body portions that are configured to provide a hinge connection; Figure 5 is a corresponding non-transparent view of the arrangement shown in Figure 4; Figure 6 is a schematic pcrspcctivc vicw illustrating the connection of thc proximal and distal body portions at a hinge of the type illustrated in Figures 4 and 5, with the proximal and distal body portions being aligned with each other; Figure 7 depicts the hinge of Figure 6 in the case where the proximal and distal body portions have been rotated rclativc to cach other to a position intcrmcdiate between the first and second relative orientations; Figure 8 depicts the hinge of Figures 6 and 7 in the case where the proximal and distal body portions have been rotated through a maximum angle with respect to each other; Figure 9 is a schematic illustration of a hinged connection between the proximal and distal body portions in which a projection formed in the distal body portion is smaller than the corresponding opening formed in the proximal body portion and is allowed to move therein in order to facilitate a greater range of angular movement between the proximal and distal body portions, thc configuration of Figure 9 conesponding to a statc in which the relative anglc between the proximal and distal body portions is insufficiently small to force the projection to move within the opening; Figure 10 is a schematic illustration of the arrangement illustrated in Figure 9 in the ease where the proximal body portion has been moved so as to reduce the angle between the proximal and distal body portions to an extent that causes the projection to be forced to an opposite end of Lhe opening relative 10 the conliguralion olFigure 9, thereby lacilitaling addiiional rolalion; Figurc 11 depicts an arrangement in which the rcgion of conncction between the distal body portion and the proximal body portion is covered by a flexible sheath having a valve; Figure 12 is a schematic illustration of an example valve; Figure 13 is a schematic illustration of device that comprises indicator elements and in which the proximal and distal body portions adopt the first relative orientation; Figure 14 is a schematic illustration of the device of Figure 13 in which the proximal and distal body portions adopt the second relative orientation.

Figure 1 is a schematic illustration of a device for introducing a medical element into a blood vessel ofa human or animal body. In an embodiment, the medical element comprises a catheter or a guide wire. The device 2 comprises a proximal body portion 4 and a distal body portion 6. The proximal body portion 4 is connected to the distal body portion 6 in a way which allows the relative orientation between them to be changed. In the example shown, the relative orientation is characterised by the angle between an axis of elongation of all or a portion of the proximal body portion 4 and an axis of elongation of all or a portion of the distal body portion 6.

In the arrangement shown, the angle between the proximal and distal body portions is approximately 90°. In an embodiment 90° represents an angle that is intermediate between a first angle representing a first relative orientation and a second angle representing a second relative orientation.

In an embodiment, the proximal and distal body portions 4,6 are connected to each other in a pivotable or hinged manner so that the angle between them can be changed. Arrow 12 illustrates an example rotation of the proximal body portion 4 away from the distal body portion 6. In this embodiment, the configuration when the proximal body portion 4 reaches alignment with axis 10 corresponds to the first relative orientation. Arrow 16 illustrates an example rotation of the proximal body portion 4 towards the distal body portion 6. In this embodiment, the configuration when the proximal body portion 4 reaches alignment with axis 14 corresponds to the second relative orientation.

In an embodiment, the device comprises an access/connection port 8 for providing access for a medical element to be inserted and/or for providing connection to other components of the medical clement insertion system. The proximal and distal body portions 4,6 comprise internal lumens defining a continuous path for a medical element to be inserted via entry 7 to exit 9. As will be described in further detail below, depending on the relative orientation adopted by the proximal and distal body portions 4,6, die medical elemeni may also exit Lhe device 2 via an opcning in the region of connection between the proximal and distal body portions 4,6.

In an embodiment, a side port is further provided. The side port may be formed in the access/connection port 8, for example, or at a position upstream or downstream of this port. The side port may be configured to allow flushing of the internal lumens and/or for the injection of a contrast agent for example. The device may further comprise a removable cap upstream of the access/connection port 8 (with or without the provision of the additional side port). The removable cap may comprise a haemostatis valve. In an embodiment the removable cap comprises a screw thread and is configured to be removable by unscrewing. The valve prevents reflux of blood once the distal body portion has been inserted into the blood vessel and at the same time will facilitate insertion of medical elements such as catheters or guidewires.

Configuring the removable cap to be removable facilitates the removal of blood clots through the device without having to pass through the haemostasis valve.

Figures 2 and 3 arc schematic side sectional view showing the device 2 in a state of insertion into a blood vessel 20. In these configurations, the proximal body portion 4 traverses through tissue 18 from the environment outside the human or animal body to the interior of the blood vessel 20. The distal body portion 6 is entirely located within the blood vessel 20.

In Figure 2, the proximal and distal body portions 4,6 arc in the first relative orientation.

The angle between the axis of elongation 24 of the proximal body portion 4 and the axis of elongation 26 of the distal body portion 6is sufficiently large to favour movement 22 of the medical element in the direction shown. In this configuration, the medical element will pass through the entire length of the distal body portion 6 and exit at the tip end 15 of the distal body portion 6. This geometry corresponds closely to the geometry which would be adopted at stages during a standard Seldingcr approach to catheter insertion. For example, the angle between the proximal body portion 4 and distal body portion 6 is similar to the angle that would be maintained by a surgeon between a trocar and/or cannula and a guide wire. Manipulation of such a configuration would therefore be a familiar process for a surgeon.

Figure 3 illustrates the device of Figure 2 after it has been switched from the first relative orientation to the second relative orientation. In this embodiinent the second relative orientation is characterised by a much smaller angle between the axis of elongation 24 of the proximal body portion 4 and the axis of elongation 26 of the distal body portion 6. In this configuration, a medical element driven through the proximal body portion 4 will exit the device at an end 17 of the distal body portion 6 opposite to the tip end 15. The movement 22 of the medical device is in thc opposite axial direction of thc blood vessel compared with thc movement 22 in thc configuration of Figure 2. In an embodiment, an opening through which the medical element can pass is defined by a gap (at end 17 of the distal body portion 6 in the example shown) between a portion of the proximal body portion 4 and a portion of the distal body portion 6. In an embodiment, the opening reduces in size or closes when the proximal and distal body portions 4,6 are switched from the second relative orientation to the first relative orientation. In an embodiment, the opening is formed on an outer side of an elbow formed by the connection between the proximal and distal body portions 4,6.

From the point of view of the surgeon, the switching of the device 2 between the first and second relative orientations can be carried out relatively easy. In the particular embodiment shown, the switching is achieved merely by rotating the proximal body portion 4 protruding to the outside of the body, fix example relative to an axis lying roughly parallel to the skin. It is not nccessary to makc any additional punctures in thc skin, nor to enlarge thc existing puncture (at least not to any significant extent). The device 2 therefbre makes it possible fbr a medical element to be inserted selectively in one or both of two different axial directions within the blood vessel quickly and easily and with minimum stress to the patient. The device 2 facilitates the insertion of additional medical elements at short notice, even when the additional medical element needs to be inserted in an axial direction within the blood vessel that is opposite to the axial direction through which medical elements have already been inserted. For example, in the case where a medical procedure is being carried out on coronary vasculature via an insertion device implanted via a single femoral artery puncture, it is possible quickly to insert a new medical device travelling in the opposite axial direction within the blood vessel via the same single femoral artery puncture to enable treatment of peripheral vasculature.

In embodiments of the type illustrated in Figures 1 to 3, the first and second relative orientations of the device 2 are defined by first and second angles, respectively, of thc proximal body portion 4 relative to the distal body portion 6. In an embodiment, the difference between the first and second angles is in the range of 45-175°. In an embodiment, the first angle is roughly equal to 180 degrees minus the second angle. In this way, the angle between the proximal body portion 4 and the skin will tend to be about the same in the first and second orientations, thereby providing consistent working requirements and/or sensations to the S surgeon. Figures 2 and 3 illustrate an embodiment of this type, where angle 25 is the same in both oFUe two relative orienlations depicted.

In an embodiment, the pivoting action between the proximal and distal body portions 4,6 is implemented by means of a mechanical hinge. Figures 4 and 5 illustrate dc-connected end portions of the proximal and distal body portions 4,6 that are configured to cooperate to provide such a hinge. Figure 4 is a schematic "transparent" perspective view, where broken lines illustrate features that are inside the depicted end portions or on an opposite side of the depicted end portions. Figure 5 is a non-transparent view corresponding to Figure 4.

In the embodiments shown, the proximal body portion 4 comprises a pair of openings 28 that are configured to receive corresponding projections 30 formed in the distal body portion 6.

The projections 30 and openings 28 have substantially the same shape and are configured such that the projections 30 can rotate relative to the openings 28 within the openings 28. In an embodiment, the rotation allows the device to switch between the first and second relative orientations. In an embodiment, the projections 30 and openings 28 are configured such that the axis of relative rotation of the projections 30 remains constant during switching between the first and second relative orientations. In the example shown, the projections 30 have a circular cross section. This configuration is relatively simple to manufacture and is robust and reliable.

In an embodiment, the projections 30 are provided on extending arms 31. The extending arms engage within a recessed region 33 of the proximal body portion 4. An indented region or opening 35 is provided in the distal body portion 6 to accommodate a portion of the proximal body portion 4 when the proximal body portion 4 has been rotated through a maximum angle of rotation. In an embodiment, the maximum angle of rotation corresponds to the second relative orientation of the proximal and distal body portions 4,6.

Figures 6 to 8 illustrate operation of the hinge depicted in Figures 4 and 5 when the end portions (and therefore the proximal and distal body portions) are connected together.

In Figure 6, the hinge is configured such that the axis of elongation of the proximal body portion 4 is aligned with the axis of elongation of the distal body portion 6. This aligned configuration may be convenient for packaging the device compactly, for example for the purposes of sale or storage.

Figure 7 illustrates how the hinge can allow rotation of the proximal body portion 4 relative to the distal body portion 6 in order for the device to adopt the configuration shown in S Figure 1. In an embodiment, the angle between the proximal and distal body portions 4,6 shown in Figure 7 corresponds to an iniermediale position between the flrst arid second relative orientations.

Figure 8 illustrates the configuration of the hinge whell the proximal body portion 4 has been rotated through a maximum angle relative to the distal body portion 6. This configuration may correspond to the second relative orientation. As can be seen, a portion of the proximal body portion 4 sits within thc indcntcd region or opening 35 and allows the anglc of the proximal body portion 4 to approach the angle of the distal body portion 6 to a greater extent.

Figures 9 and 10 illustrate an alternative embodiment in which the projection 30 formed in the distal body portion 6 have a different shape and/or size to the openings 28 in the proximal body portion 4. In an embodiment, the projections 30 and openings 28 allow the axis of relative rotation of the projections 30 to change during the switching between the first and second relatiye orientations. In the arrangement shown, the projections 30 have a substantially circular cross-section whereas the openings 28 have an elongate shape. In the embodiment shown, the direction of elongation of the opcnings 28 is substantially parallel to the axis of clongation of thc distal body portion 6 when the proximal body portion 4 is inhibited (but lot prevented) from further rotation by the distal body portion 6. In an embodiment, the axis of elongation of the opening 28 is substantially perpendicular to the axis of elongation of the proximal body portion 4 within which it is formed. In this casc, any opposition to a torque tending to rotate thc proximal body portion 4 (i.e. an "inhibition") will tend to provide the basis for moving the projections 30 in the direction of elongation of the openings 28. In an embodiment, the inhibition occurs when the proximal body portion 4 reaches an angle relative to the distal body portion 6 at which a portion 37 of the distal body portion 6 comes into contact with the proximal body portion 4. The openings 28 in the proximal body portion 4 are configured to allow further rotation of the proximal body portion 4 towards the distal body portion 6 by allowing the projections 30 to move within the openings 28. The axis of relative rotation of the projections 30 thus changes (c.g. shifts latcrally, so that the different axes of rclativc rotation are parallel but spaced apart from each other). In the example shown the further rotation of the proximal body portion 4 is illustrated by arrow 32 in Figure 10. The movement of the projections 30 within the opening 28 is illustrated by arrow 34 in Figure 10. In an embodiment, the further rotation comprises pivoting about the point or line of contact between portion 37 of the distal body portion 6 and the proximal body portion 4.

Figure 11 illustrates schematically an alternative embodiment in which the proximal body portion 4 is formed integrally with Lhe disial body portion 6. In embodiments olthis type, switching between the first and second relative oricntations is achieved by bending the proximal body portion 4 relative to the distal body portion 6. In an embodiment, the bending is achieved by localised deformation of the material forming the proximal and distal body portions 4,6 in the region of connection between them. In an embodiment, the dimensions, material and/or first and second relative orientations are chosen such that the cross-sectional area of a lumen passing from the proximal body portion 4 to the distal body portion 6 is maintained within 50%, preferably 20%, of the maximum internal cross-section of the proximal body portion 4 or distal body portion 6 throughout the whole or a majority of the range of motion between the first and second relative orientations. In an embodiment, the proximal and distal body portions 4,6 comprise hyper-elastic material, at least in the region of connection between them, in order to facilitate the maintenance ofa sufficiently large lumen within the device 2.

In an embodiment, a flexible sheath 36 is provided that surrounds the region of connection between the proximal and distal body portions 4,6. In an embodiment, the flexible sheath 38 covers an opening between the proximal and distal body portions 4,6 in a region of connection between the proximal and body portions 4,6. In an embodiment, the flexible sheath 38 comprises a cylindrical tube in a resting (e.g. non-stretched) state. In the arrangement of Figure 11, the sheath 36 is provided around the region of connection between proximal and distal body portions 4,6 that are integral with each other. However, the use of a flexible sheath is not restricted to embodiments of this type. The flexible sheath can also be provided in arrangements in which a mechanical hinge is provided between the proximal and distal body portions 4,6, such as in arrangements of the type illustrated in Figures Ito 10.

In an embodiment, the flexible sheath comprises a valve 38. In an embodiment, the valve 38 is configured to allow the medical element to be pushed out of the device 2 through the valve 38 when the proximal and distal body portions 4,6 are in the second relative orientation. This is illustrated in Figure 11 by arrow 42. In an embodiment, the valve 38 is configured to prevent or substantially limit blood flow entering the device 2 when the medical element is not passing through the valve 38. In an embodiment, the flexible sheath 38 is formed from a material that is impermeable to blood. In an embodiment, the flexible sheath 38 is formed from an elastic material. In an embodiment, the flexible sheath 38 is mounted on the proximal and distal body portions 4,6 in a stretched state. The restoring force associated with the stretched state acts to press the flexible sheath 38 against the proximal and distal body portions 4,6 and helps to maintain the seal between the flexible sheath 38 arid the proximal and distal body portions 4,6.

Figure 12 is a schematic end view of the elbow portion of Figure 11 showing an example configuration for the valve 38 in the flexible sheath 36. In this example the flexible sheath 36 is cut along crossed lines 45. The lines 45 define flaps 46 that can displace relative to the rest of the sheath 36 to provide an opening for a medical element to pass through. lfthe medical element is not present, blood flow and/or the elastic properties of the sheath 36 will force the flaps 46 into a closed configuration.

In an embodiment, either or both of the proximal and distal body portions 4,6 comprise indicator elements. In an embodiment, the indicator elements are detectable optically.

Depending on the position of such indicator elements, they may be visible prior to insertion of the device in the blood vessel only, prior to and during part of the insertion process only, or at all times, even after complete insertion into the blood vessel. In other embodiments, some or all of the indicator elements are detectable using other radiation, such as radio waves, which pass through soft tissue and allow the position of the indicator elements to be determined even when they are not visible to the naked eye. In an embodiment, the indicator elements may be referred to as passive tags where they are detectable by reflecting non-visible radiation. In the ease where radio waves are used for this purpose, they may be referred to as RF tags. In other embodiments, the indicator elements may be configured actively to emit detectable radiation.

Figures 13 and 14 illustrate an example arrangement in which both the proximal and distal body portions 4,6 comprise indicator elements 52,54,56,58. Figure 13 illustrates the device when the proximal and distal body portions 4,6 adopt the first relative orientation (for insertion of a medical element to the right in the orientation of the figure as shown). Figure 14 illustrates the device when the proximal and distal body portions 4,6 adopt the second relative orientation (for insertion of a medical device to the left in the orientation of the figure as shown).

In this particular example, the proximal portion 4 comprises a mark 52 that is positioned at a predetermined distance from the end of the proximal body portion 4. The relative distance between the mark 52 and the skin can easily be recognised by a person inserting the device and used as a guide to assist with effective insertion. The mark 52 may also be used for evaluating the degree of insertion of a device that has been inserted at a previous time. For example, the mark 52 may be positioned so that when correctly inserted the mark 52 is at about the same level as the skin or just above. This is the case in the example shown in Figures 13 and 14 where the S skin level is schematically indicated by broken line 50.

In the example olFigures 13 and 14, Further indicator elements comprising passive tags 54, 56 and 58 arc provided, respectively at the distal end of the proximal body portion 4, the proximal end of the distal body portion 6 and the distal end of the distal body portion 6. In an embodiment, the positions of the passive tags is determined by reflecting radio waves off them.

It is thereby possible for a medical practitioner to determine whether the device is inserted appropriately in the blood vessel. For example, the medical practical can determine whether the proximal and distal body portions 4,6 are in the first relative orientation (as in Figure 13) or in the second relative orientation (as in Figure 14). In an embodiment, the passive tags 54,56,5 8 are also visible when not yet inserted and can be referred to during insertion to assist with the insertion process.

Claims

CLAIMS1. A device for introducing a medical element into a blood vessel of a human or animal body, comprising: a proximal body portion and a distal body portion, the proximal body portion being connected to the distal body portion in such a way as to allow switching ofthc relative orientation between the proximal and distal body portions between a first relative orientation and a second relative orientation, the device being configured such that: when the distal body portion has been inserted into the blood vessel, a medical element can be inserted into the blood vessel through the proximal body portion in one axial direction of the blood vessel when the proximal and distal body portions are in the first relative orientation and in the other axial direction of the blood vessel when the proximal and distal body portions are in the second relative orientation.
2. A device according to claim 1, wherein the medical element comprises one or more of the following: a guide wire, a catheter.
3. A device according to claim 1 or 2, wherein: the proximal and distal body portions are elongate.
4. A device according to any of the preceding claims, wherein: the first relative orientation represents a state in which an axis of elongation of all or a portion of the proximal body portion is at a first angle relative to the axis of elongation of all or a portion of the distal body portion; the second relative orientation represents a state in which the axis of elongation of all or a portion of the proximal body portion is at a second angle relative to the axis of elongation of all or a portion of the distal body portion; and the first angle is different to the second angle.
5. A device according to claim 4, wherein the difference between the first and second angles is in the range of 45-175 degrees.
6. A device according to claim 4 or 5, wherein the first angle is approximately 180 degrees minus the second angle.
7. A device according to any of claim 4-6, further comprising a mechanical hinge connecting the proximal body portion to the distal body portion.
8. A device according to claim 7, wherein the mechanical hinge comprises: a projection fbrmed in the proximal body portion and configured to engage rotatably in a corresponding opening in the distal body portion; or a projection funned in the distal body portion and configured to engage rotatably in a corresponding opening in the proximal body portion.
9. A device according to claim 8, wherein the projection is configured to rotate relative to the opening within the opening to allow switching between the first relative orientation and the second relative orientation.
10. A device according to claim 9, wherein the projection and opening are configured such that the axis of rclativc rotation of thc projection remains constant during the switching between the first relative orientation and the second relative orientation.
11. A device according to any of claims 8-10, wherein the opening has substantially the same shape as the projection.
12. A device according to claim 8 or 9, wherein the projection and opening have different shapes and/or sizes to allow the axis of relative rotation of the projection to change during the switching between the first relative orientation and the second relative orientation.
13. A device according to claim 12, wherein the opening is elongate.
14. A device according to claim 13, wherein the axis of elongation of the opening is substantially perpendicular to the axis of elongation of the proximal or distal body portion within which the opening is formed.
15. A device according to any of the preceding claims, configured such that the medical element enters the blood vessel ii rough a first end olthe distal body portion when the proximal and distal body portions arc in the first orientation and through a second end of the distal body portion when the proximal and distal body portions are in the second orientation, the first end being opposite to the second end.
16. A device according to claim 15, wherein the second end of the distal body portion is located at the region of comiection between the proximal and distal body portions.
17. A device according to any of the preceding claims, wherein: an opening is defined by a gap between a portion of the proximal body portion and a portion of the distal body portion when the proximal and distal body portions are in the second relative orientation.
18. A device according to claim 17, configured so that the opening reduces in size or closes when the proximal and distal body portions are switched from the second relative orientation to the first relative orientation.
19. A device according to claim 17 or 18, wherein the opening is formed on an outer side of an elbow formed by the connection between the proximal and distal body portions.
20. A device according to any of the preceding claims, further comprising a flexible sheath surrounding the region of connection between the proximal and distal body portions.
21. A device according to claim 20, wherein the flexible sheath comprises a valve.
22. A device according to claim 21, wherein the valve is configured to allow the medical device to be pushed through the valve when the proximal and distal body portions are in the second relative orientation.
23. A device according to claim 21 or 22, wherein the valve is configured to prevent blood flow entering an opening beiween Lhe proximal and distal body portions when We medical device is not passing through the opening.
24. A device according to any of claims 20-23, wherein the flexible sheath is formed from a material that is impermeable to blood.
25. A device according to any of claims 20-24, wherein the flexible sheath is formed from an elastic material and is mounted on the proximal and distal body portions in a stretched state, the restoring force acting to press the flexible sheath against the proximal and distal body portions and thereby maintain a seal between the flexible sheath and the proximal and distal body portions.
26. A device according to any of the preceding claims, wherein the proximal body portion is integrally formed with the distal body portion.
27. A device according to claim 26, wherein the switching between the first and second relative orientations is achieved by bending the material of the proximal and distal body portions in the region of connection between the proximal and distal body portions.
28. A device according to claim 26 or 27, wherein the dimensions, material and/or first and second orientations are chosen such that the cross-sectional area of a lumen passing from the proximal body portion to the distal body portion remains within 50% of the maximum internal cross-section of the distal body portion during the whole or a majority of the switching process from the first relative orientation to the second relative orientation.
29. A device according to any of the preceding claims, wherein the proximal and distal body portions comprise hyper-elastic material.
30. A device according to any of the preceding claims, wherein the distal body portion comprises a tapered or sharpened portion to facilitate insertion into the human or animal body.
31. A device according to any of the preceding claims, wherein the proximal body portion, the distal body portion, or both, comprise(s): an indicator clcmcnt configurcd to bc dctcctablc during and/or after insertion of thc device into the blood vessel.
32. A device according to claim 31, wherein the indicator element comprises one or more marks on the proximal body portion, the distance(s) between the one or more marks and the skin during insertion indicating a degree of insertion of the device into the blood vessel.
33. A device according to claim 31 or 32, wherein the indicator element comprises one or more tags, each configured so that the position of the tag can be detected by intercepting non-visible radiation emitted by the tag or reflected from the tag.
34. A device according to claim 33, wherein the one or more tags is/are located at one or nre of thc %llowing positions: a distal cnd of the proximal body portion, a proximal end of the distal body portion, a distal end of the distal body portion.
35. A device according to any of the preceding claims, flirther comprising a port through which the medical element can be inserted into the proximal body portion.
36. A device according to claim 35, further comprising a side port providing an additional access to the proximal body portion.
37. A device according to claim 35 or 36, further comprising a removable cap configured to be removably attached to the device upstream from, and limiting or block access to, said port through which the medical device can be inserted into the proximal body portion.
38. A device according to claim 37, wherein the removable cap comprises a haemostasis valve.
39. A method of using a device according to any of the preceding claims, comprising: inserting the distal body portion into the blood vessel; inserting a fitst medical element through the proximal body portion and into the blood vessel along thc one axial direction within the blood vessel; switching the proximal and distal body elements from the first relative orientation to the second relative orientation; and inserting a second medical element through the proximal body portion and into the blood vessel along the other axial direction within the blood vessel.
40. A device arranged and configured to operate substantially as hereinbefore described with reference to and/or as illustrated in the accompanying drawings.