DE102008015050A1 - Tracheostomy tube made of at least two different plastics - Google Patents

Abstract

The present invention relates to a tracheostomy tube with a tube (1), which consists of at least two different elastic plastics, one of which is softer and has a smaller modulus of elasticity and the other is relatively harder and has a relatively greater modulus of elasticity, and a method for Production of such a cannula. In order to provide a tracheostomy tube with the features mentioned, which is easier to produce, the invention proposes that the softer plastic is made in a tubular shape and groove-like or groove-like recesses (4, 5) has at least either on its inside or on its outer side, of which at least a part extends predominantly in the circumferential direction and which are filled with the harder plastic. A corresponding manufacturing method is characterized in that first a plastic tube made of soft plastic material (2) with recesses (4, 5) on either its outer (6) or its inner side (7) is produced and then the harder plastic material (3) this side of the soft tube is sprayed, wherein at least the recesses (4, 5) are filled. Conversely, a skeleton of harder material can be coated with the softer material.

Description

The The present invention relates to a tracheostomy tube with a hose made of at least two different elastic Consists of plastics, one of which is softer and one smaller Young's modulus has and the other relatively harder is and has a relatively larger modulus of elasticity, wherein at least the softer plastic is produced in tubular form is.

A corresponding tracheostomy cannula is known, for example from the EP 0 950 424 A2 , This document relates to a method for producing reinforced, medical tubing, including tracheal tubes and Tracheotomietuben (or tracheostomy tubes) are to be counted. The reinforcement of such hoses is a spiral reinforcement in the form of a metal wire or a plastic filament. This is introduced into the hose wall at a predetermined bond distance. This is done in such a way that first a base tube is extruded from a polymeric material and on the cooled surface of the spiral is wound. Subsequently, the outer tube layer of a polymeric material is applied to this combination of base tube and spiral. Additionally, the outer circumference of the base tube is coated with an adhesive prior to winding the coil. The spiral is embedded in this way between the base tube and the outer tube layer and connected via the adhesive in such a way with these tube materials, that when separating a tube section, the free end of the filament does not protrude from the end face of the tube. As an example of the material of the basic tube but polyvinyl chloride is given with a plasticizer content of at least 10%, while the filament can be made in this example of rigid PVC. Alternatively, the reinforcement is provided by means of a metal spiral.

This known manufacturing process is relatively expensive. The wall thickness the corresponding cannulas is relatively large, the Filament must be surrounded on all sides by soft material.

Across from This object of the present invention is the object of this prior art underlying, a tracheostomy tube with the aforementioned To create features that is easier to produce.

Regarding The tracheostomy tube itself accomplishes this task solved that the tube-shaped softer Plastic at least either on its inside or on its Outer groove or groove-like depressions, of which at least a part is predominantly or entirely in Circumference runs, and those with the harder Plastic are filled.

According to one Embodiment, the wells are only on the outside provided the soft tube and according to a In another embodiment, the recesses are only on the inside provided the soft tube, although also embodiments conceivable, both on the inside and on the outside have corresponding recesses, too if such variants are not preferred.

Of the recorded in the recesses of the softer plastic material harder plastic causes stiffening and stabilization the softer, tubular plastic material. The Cannula or consisting of the two plastic components Hose can therefore be bent without kinking and without severe Querschnittreduzierungen occur. This is just in the case of tracheostomy tubes especially important since the needles introduced into a tracheostoma necessarily have to have a certain curvature, depending on the anatomical conditions of a patient vary, so that in particular special also desirable is the curvature of such a tracheostomy tube to change if necessary, without thereby the free Lumen of the cannula excessively reduced becomes.

simultaneously the production of such a cannula is relatively simple, because the complex winding process of a filament is eliminated and for example the softer plastic tube by injection molding can be made with appropriate wells. For improvement the stability of the tracheostomy tube is according to a Embodiment provided that at least one the wells wholly or predominantly in the axial direction runs and others, entirely or predominantly predominantly connecting in the circumferential direction recesses interconnected. This creates a coherent ribbed structure in which a series of, for example, parallel, extending in the circumferential direction Ribs through a further extending in the axial direction rib be joined together so that a structure similar like a skeleton with a spine and arranged on it Ribs arise.

Moreover, according to one embodiment of the invention, it is also possible that the harder plastic not only fills the recesses, but (preferably in a thin layer) also covers the remaining part of the respective surface of the softer tube, in which the recesses are provided. The layer thickness of the harder plastic is less than one tenth of the wall thickness of the tube, preferably less than 1/20.

The Depressions preferably have a depth between 0.2 and 1 mm, preferably 0.4 ± 0.1 mm.

Farther is provided in an embodiment of the invention, that at least along a portion of the cannula a embedded in the wall of the softer tubing, in essential axis-parallel channel is provided, the lumen in radial direction of the hose a smaller amount than the intended in this area wall thickness of the softer Has tubing. If the channel is in a peripheral area which also extends from the circumferentially extending ribs is detected, the lumen of the channel must be smaller its than the wall thickness of the softer tubing minus the depth of the corresponding wells for Ribs.

The Wells can approximate the shape of grooves have rectangular cross section, of course the corner areas of such a cross section even with a small Radius can be rounded.

According to one In another embodiment, the recesses are in the form of Grooves with a strongly rounded base and strongly rounded transitions formed to the surface, so that in cross section a Wave or trough shape for the depression results. It understands itself, that between the more rectangular groove shape and the strongly rounded groove shape arbitrary transitions for the cross section of the grooves and the corresponding ribs possible are.

According to one Embodiment is provided that the ribs extending in the circumferential direction over more than 180 °, wherein the connected via an axially extending rib Ribs which are approximately in the same axial position, as one extending beyond the axial rib only Rib are viewed. Ultimately, it is important that the Forming rib structure as a whole in the circumferential direction ribs, spread over more than half the size the softer tubing extends to stabilize this sufficiently to be able to. On the other hand, but according to one Embodiment also provided that the ribs extending over less than 360 °, so that in Cross-section seen a certain angle range of the softer tubing is omitted from corresponding ribs. Conveniently, is preferably provided in exactly this area a channel, such as he has already been defined above and as in the case of tracheostomy tubes for example, for filling a sealing collar or for Aspirate from above or below a cuff accumulating Secretion may be provided. It goes without saying that too several such channels in the soft tubing can be embedded. If necessary, the wall thickness the softer tubing in the region of such channels be a little bit bigger.

According to one Another embodiment of the invention form the ribs Closed rings and you can also over more as an axially extending further rib with each other be connected. However, the ribs have to, though they do not extend over more than 360 ° necessarily form closed rings, but they can have free, axially or radially offset ends, the overlap only in a sectional view perpendicular to the axis, but have no direct contact with each other.

It is understood that the plastics of the softer and the harder material compatible with each other or good adhering plastics should be, but less compatible plastics too Can be used when considering the two components connects by positive engagement with each other, so for example the Rip the hardened material in undercut wells or in grooves that are close to the bottom of the groove are further than in the slot opening.

According to one Embodiment, the softer plastic has a Shore A hardness between 20 and 90, while the harder plastic has a Shore D hardness of more than 40. Alternatively you can the properties of the harder plastic by a Bend modulus or modulus of elasticity describe after ASM standard with a strain of 100% of a tension of at least 8 MPa corresponds. A reasonable upper limit for the modulus of elasticity is about 500 MPa, without the subject invention should be limited to such a value. In practice, plastics prove themselves for the harder component with a modulus of elasticity in the range of 20 to 40 MPa.

Furthermore Both plastic materials can be polyurethane, where It is also possible, in particular, polyurethane in accordance to produce different hardnesses. Alternatively, however, come other TPEs and in particular materials such as EVA, TPO, PVC, Pebax, styrene-containing copolymers such as SEES and SBS, silicone or any other elastomers in question, being for the hard Material also polypropylene, PEEK, polyamide or polyester and corresponding Copolymers / block copolymers can be used.

According to one embodiment, one of the plastics has an X-ray contrast agent, such as. B. BaSO ₄ , making the cannula radiopaque.

Regarding of the method of making a tracheostomy tube as described above, it is proposed according to the invention that first a plastic tube made of a soft Plastic material with depressions on at least one of his Outside or its inside is made and then the harder plastic material on this side of the soft tube is applied, wherein at least the recesses of the soft Hose filled with the hard material.

there The soft plastic tube can either be injection molded or be extruded. The harder plastic material can can also be extruded or it can be sprayed in a mold become. In this case, if necessary, the harder plastic material also between the depressions on the surface of the soft Plastic material are applied.

A another possibility for producing the soft tube component consists in the technique of extrusion blown, that in Zegensatz to the usual extrusion process of the production of the Length of varying sections and more complex shapes allowed.

According to one another variant of the manufacturing method according to the invention it is envisaged that first a coherent Rib structure of partially predominantly in the circumferential direction and partially axially extending ribs from the harder Plastic material is produced and then the soft plastic material is applied to this rib structure. It is understood that while only an axially extending Rib is required, even if several such ribs if necessary can be provided. These axially extending ribs can also be short by pinning or clamping together consist of connectable sections.

The Width of the ribs or depressions should typically be between 0.2 and 1 mm, although other widths quite possible are. The clear axial distance a between the circumferentially running adjacent ribs is according to a Embodiment between 1 and 15 mm, this distance for example, over the length of the cannula can be constantly maintained, according to a Embodiment but also over the length may vary across the cannula, for example, stronger to curving and / or more heavily loaded sections The cannula provides additional improved stiffness by giving the distances in these areas the ribs reduced.

By By varying the thickness and width of the ribs one can see the stiffness the total cannula vary.

According to one Embodiment should be at least the hard plastic material not only elastic, but also plastically deformable and that at a relatively low temperature, e.g. B. between 20 ° and 50 ° C., So that one on the tracheostomy tube deliberately applied at or immediately before insertion Curvature is maintained without the cannula springs back in their original form. It may be appropriate be, if the plastic deformation only above 40 ° C possible, d. H. at a temperature that is above body temperature, but if touched can not lead to burns. In particular, when using a plastically deformable plastic for the harder Component the cannula also in the form of a straight tube be prepared, the curvature only when using adjusted and adapted to a patient. Such plastics are known per se and available for example from the Eastman under the name Eastar Coplyester. Also polyisobutylene is such a plastically deformable plastic, the u. a as an additive be introduced into another harder plastic can.

In In one embodiment, the cannula has an oval Cross-section showing the insertion between the cartilage clasps of the Larynx relieves and protects them. The rib structure provides but still for sufficient stability and prevents complete or extensive squeezing the cannula cross-section itself when bending the cannula around a small radius of curvature.

The Cannula can further be formed in two parts and with a be equipped with additional inner cannula. she also according to one embodiment a movable shield to the plant or support and Positioning on the neck of a patient.

Further Advantages, features and applications of the invention will become clear from the following description of a preferred Embodiment and the associated figures. Show it:

1 a perspective view of a tube provided with corresponding recesses made of a soft tube material,

2 a running perpendicular to the axis section through the hose 1 in the area of one of the depressions 4 .

3 one perpendicular to the axis the section through the tube of Figure with a sectional plane between two wells 4 .

4 a longitudinal sectional view of the tube after 1 .

5 a 4 corresponding side view, but in which the wells are filled with harder plastic material and thus a rib structure 14 . 15 form,

6 schematically a rib structure of the harder plastic component

7 schematically a rib structure of individual zusammenclipsbaren elements, and

8th schematically a rib structure of individual, non-contiguous elements.

The Figures give the actual object only schematically and not necessarily in the right proportions again.

One recognizes in 1 in a perspective view a portion of one of a soft material 2 manufactured hose, wherein the end face of this tube corresponds to a cross-sectional image between two ribs. It can be seen in particular in this view, a channel 8th which is in the wall of the hose 2 is embedded and the extending in the axial direction depression 5 is arranged diametrically opposite one another. It is understood that both the channel 8th as well as the depression 5 should not be exactly axial, but could also be inclined to the axis and slightly spiral. Also the circumferentially extending depressions 4 not necessarily have to run exactly in the circumferential direction without any axial component, but they may also have small components in the axial direction, but should have predominant components in the circumferential direction.

Especially in the sectional view according to 2 making a cut in the area of a depression 4 shows, you can see that the wells 4 in total over a circumferential angle between 180 and 360 °, z. B. about 270 °, extend, but this angle may vary within wide ranges, for. B. can have any value between 180 ° and 360 °.

Each of the wells 4 . 5 has a depth (t), where here are the pits 4 and 5 are shown with the same depth (t), but in practice the depth of the recess 5 may be larger or smaller than that of the wells 4 , This depth t in preferred embodiments is between 0.1 to 0.8 times, preferably between 0.2 to 0.5 times the total wall thickness of the cannula.

3 shows a section in a plane parallel to the cutting plane of 2 but in a region between two adjacent recesses 4 , In this cross-section can be seen only the axially extending recess 5 and the channel 8th ,

It is understood that also several substantially extending in the axial direction depressions 5 the wells 4 could connect with each other. In the longitudinal section according to 4 that by the recess 5 and the diametrically opposite channel 8th runs, dashed also recognizes the provided on the side behind the paper plane side parallel depressions 4 passing through the recess 5 connected to each other.

4 shows a longitudinal sectional view of the finished tube, with a through the recess 5 running cutting plane. These are behind the plane of the paper and on the outside of the hose 2 lying depressions 4 dashed lines. The axial repeat distance of the recesses 4 is denoted by a, its radial depth by t.

5 shows a side view, in which now the wells 4 . 5 are filled by a harder plastic material, which thereby a rib structure of circumferentially extending ribs 14 and an axially extending rib 15 forms.

The ribbed structure made of the harder plastic is preferably plastically deformable, especially in one relatively low temperature, such. Below 50 or 60 ° C, so that one of the cannula at a corresponding Temperature imposed curvature after insertion at least largely preserved.

6 shows a rib structure of the harder plastic material for a variant of the corresponding manufacturing process 3 , So instead of the example of 1 to 5 Initially, to produce a softer plastic tube with recesses, one can alternatively of a rib structure according to 6 go out and coat them on one side or on both sides with softer plastic material, thereby creating a tracheostomy tube, which has the same structure and the same structure as in the 4 and 5 illustrated tracheostomy cannula. In this case, however, the rib structure may also be enveloped on all sides by the softer plastic material and it would also be possible to make the tracheostomy tube so that the ribs 14 . 15 define the inner cross section of the tube thus formed.

In the above manufacturing method, the rib structure may also be modular be constructed of several sections or segments, for example, overlap each other at their ends and to the entire rib structure via latching buttons 16 be clipped together, as in the case of 7 is indicated.

8th shows finally a variant, which consists only of circumferentially extending and axially spaced, separate ribs 14 There may also be circumferential rings or pipe sections. In this case, the distance of the individual rings or pipe segments, as well as their axial dimension over the length of the corresponding hose 2 vary. to achieve locally different bending stiffnesses. A connecting longitudinal rib 15 as in the case of 6 and 7 is not intended.

The Tracheostomy tubes of the invention can be endless or predetermined depending on the manufacturing process Sections produced (for example by injection molding) become. This type of production is relatively simple and straightforward and leads to inexpensive but functionally improved Tracheostomy.

For Purpose of the original disclosure is pointed out that all features, as they result from the present Description, the drawings and the claims for develop a specialist, even if they are specifically only in Context with certain other features have been described, both individually and in any combination with others the features or feature groups disclosed here can be combined unless expressly excluded or technical conditions such combinations impossible or make pointless. This also applies to features that work together are included in a dependent claim. On the comprehensive, explicit representation of all conceivable combinations of features in addition to those arising from the independent Claims arise here is only the brevity and omitted for the readability of the description.

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• EP 0950424 A2 [0002]

Claims (26)

Tracheostomy tube with a tube ( 1 ), which consists of at least two different, elastic plastics, one of which is softer and has a smaller modulus of elasticity and the other is relatively harder and has a relatively larger modulus of elasticity, characterized in that the softer plastic is made in a tubular shape and at least either groove-like or grooved depressions on its inside or on its outside ( 4 . 5 ), of which at least one part extends predominantly in the circumferential direction and which are filled with the harder plastic. Tracheostomy tube according to claim 1, characterized in that the depressions ( 4 . 5 ) are provided only on the outside of the cannula. Tracheostomy tube according to claim 1, characterized characterized in that the depressions only on the inside the cannula are provided. Tracheostomy tube according to one of claims 1 to 3, characterized in that the harder plastic in addition to the depressions ( 4 . 5 ) the remainder of the surface of the relevant external ( 6 ) or inside of the softer tubing ( 2 ) covered. Tracheostomy tube according to one of claims 1 to 4, characterized in that at least one of the depressions ( 5 ) runs entirely or predominantly in the axial direction and predominantly in the circumferential direction extending depressions ( 4 ) connects to each other. Tracheostomy cannula according to one of the preceding claims, characterized in that at least along an axial section of the cannula a cannula is inserted into the wall of the softer plastic material ( 2 ) embedded, substantially paraxial channel ( 8th ) is provided, the lumen in the radial direction of the tube has a smaller dimension than the wall thickness D of the softer tubing ( 2 ), optionally minus the depth (t) of the depressions ( 4 . 5 ). Tracheostomy tube according to one of the preceding claims, characterized in that the depressions ( 4 . 5 ) have the shape of grooves of approximately rectangular cross-section. Tracheostomy tube according to one of claims 1 to 6, characterized in that the depressions ( 4 . 5 ) the shape of grooves with a strongly rounded bottom and rounded transitions to the surface of the softer plastic material ( 2 ) to have. Tracheostomy tube according to one of the preceding claims, characterized in that the recesses extending predominantly in the circumferential direction ( 4 ) filling harder plastic ( 3 ) the shape of ribs ( 14 ), each extending over more than 180 ° in the circumferential direction. Tracheostomy tube according to claim 9, characterized in that the ribs ( 14 ) extend over less than 360 ° in the circumferential direction. Tracheostomy tube according to claim 9, characterized in that the ribs ( 14 ) form closed rings. Tracheostomy tube according to claim 9, characterized in that the ribs ( 14 ) extend over more than 360 ° and thereby have free, axially or radially staggered ends. Tracheostomy tube according to claim 9, characterized characterized in that the ribs are contiguous and are formed spirally encircling. Tracheostomy tube according to one of claims 9 to 14, characterized in that the axial distance (a) of adjacent ribs ( 14 ) over the length of the cannula ( 1 ) varies. Tracheostomy tube according to one of claims 9 to 14, characterized in that the axial distance (a) of adjacent ribs ( 14 ) over the length of the cannula ( 1 ) is substantially constant. Tracheostomy tube according to one of the preceding claims, characterized in that the radial depth (t) of the depressions ( 4 . 5 ) is between 0.2 and 1 mm and smaller than the wall thickness (d) of the softer plastic material ( 2 ). Tracheostomy tube according to one of the preceding Claims, characterized in that the softer and the harder plastic made compatible with each other and / or plastic materials adhering well to one another. Tracheostomy tube according to one of the preceding Claims, characterized in that the softer Plastic has a Shore A hardness between 20 and 90 and the harder plastic a Shore D hardness of more 40 or alternatively a modulus of elasticity of more than 8 MPa, preferably more than 20 MPa. Tracheostomy tube according to one of the preceding Claims, characterized in that both plastics Made of polyurethane. Tracheostomy tube after one of the first existing claims, characterized in that at least the harder plastic ( 3 ) is plastically deformable. Method for producing a tracheostomy tube according to one of the preceding claims 1 to 20, characterized in that initially a plastic tube made of soft plastic material ( 2 ) with depressions ( 4 . 5 ) on either its external ( 6 ) or its inside ( 7 ) and then the harder plastic material ( 3 ) is sprayed on this side of the soft tube, wherein at least the recesses ( 4 . 5 ) fill out. Method for producing a tracheostomy cannula according to one of Claims 1 to 20, characterized in that initially a coherent rib structure consists of partially predominantly circumferentially and partially predominantly axially extending ribs (Fig. 14 . 15 ) made of the harder plastic material ( 3 ) and then the soft plastic material ( 2 ) on this rib structure ( 14 . 15 ) is applied. Method according to claim 22, characterized in that that the rib structure is composed of rib modules, in particular, is clipped, with each module at least a pair of ribs and an axially extending structure portion and has the axially extending structure sections like a chain with each other are connectable to the structure of at least one axially extending and a plurality of circumferentially extending ribs. A method according to claim 22 or 23, characterized in that the soft plastic material is applied to the previously prepared rib structure of harder plastic material ( 2 ) is extruded. Method according to claim 22 or 23, characterized in that the ribbed structure ( 14 . 15 ) in the dipping process with the softer plastic material ( 2 ) is coated. Method of making a tracheostomy tube according to one of claims 21 to 25, characterized that the inner and / or the outer surface the cannula with a thin layer of the harder Plastic is coated