Balloon with a multi-layer wall structure for tissue-protective low-pressure sealing of openings and cavities in the patient's body, in particular in the case of periodic fluctuations in the filling pressure value

Abstract

The invention describes a multilayer balloon membrane material (1) which combines one or several layers of elastically deformable material (2) with one or several layers of plastically deformable, inelastic material (3), wherein the inelastic layers counteract the straightening properties of the elastic layers in the case of planar folding or bending of the balloon membrane material. In particular, the cross-sectional area of the eye- or channel-like structures (6) for guiding secretions or liquids, which are typically produced in the region of the plicated invagination of the balloon membrane with dimensional redundancy in organ cavities or body cavities, can be reduced, and in particular stabilized in the case of a periodic change in the balloon filling pressure, whereby an optimal sealing closure or packing result is achieved over as large a range of filling pressure amplitudes as possible.

Description

Technical Field

[0001] The present invention relates to a balloon-like structure, particularly as a component of a catheter, for positioning in a manner within a cavity, such as a lumen or other cavity, in the body of a human or animal, such that the cavity is filled as completely as possible, i.e., without any remaining space, but the cavity generally maintains its shape or is not deformed by the balloon body. Background Technology

[0002] In many cases, catheter applications within a patient require balloon-like components that seal or fill the lumen of the catheter, maintaining the sealing and / or filling function of the balloon even when the cross-sectional area of ​​the lumen to be sealed or the volume of the space to be filled fluctuates intermittently or, for example, periodically due to the physiological function of the corresponding structures or due to body movement. Furthermore, for balloon components placed in the body for extended periods, the forces transmitted from the balloon to adjacent tissues and structures should be sufficient to maintain perfusion and prevent pressure-induced lesions.

[0003] EP 1 061 984 A1 specifically addresses the sealing of the trachea by pharyngeal secretions, proposing a fundamental solution for the problem of efficiently and biocompatiblely sealing organs or cavities. The special qualities of the tracheal seal described in this case are largely based on the use of a balloon membrane with extremely thin walls made of polyurethane (PUR).

[0004] In this manufacturing process, the circumference of the balloon (Cuff) exceeds the circumference of the tracheal segment to be sealed. This results in a typical invagination pattern (Einstülpungsmuster) when the balloon, with its dimensional redundancy, is filled into the relatively small trachea. The excess balloon material along its circumference forms radial invaginations, following the spoke-like orientation. These invaginations, at their blind ends (the ends facing the balloon center), create specific channel-like morphologies along the balloon's longitudinal axis, allowing secretions or fluids to flow freely. The formation of these invaginations is crucial for low-pressure characteristics and maintaining perfusion of adjacent structures. Based on the invagination principle of the dimensionally redundant balloon cuff, it is ensured that, to seal the corresponding lumen or space, the cuff can be stress-free by "folding" into the patient's corresponding lumen or involved cavity without entering a force-intensive expansion state, achievable with a balloon filling pressure only slightly exceeding the corresponding local pressure. In this way, the shape and size of the patient's lumen or other cavities are maintained.

[0005] For balloon sheaths with dimensional redundancy constructed from PUR, EP 1 061 984 A1 describes a specific wall thickness range of 5 to 20 μm, in which, for in-situ placement of the balloon sheath, a channel-like morphology is achieved, the inner diameter of which impedes the free flow of secretions or creates a stagnant capillary effect on secretions. According to EP 1 081 984 A1, the diameter of the small channel is less than 0.11 mm, preferably less than 0.05 mm.

[0006] Aside from the specific implementation of the material of the sheath itself, the diameter of the small channels formed in the indentation of the cuff, which adjusts with tracheal breathing, largely depends on the current inflation pressure in the balloon. If the inflation pressure decreases, the channel-like structure begins to expand, with the small channels gradually opening from the corresponding blind end of the indentation towards the tracheal side base or opening of the indentation. If the inflation pressure in the balloon decreases further, the indentation fully converges towards the tracheal mucosa and enters a configuration that is generally U-shaped or W-shaped radially. The size of the indentation opening, or the cross-sectional area of ​​the small channels achieved in this case, determines the sealing capability of the cuff at a given point in time.

[0007] Within the realm of such sealed or tamponade balloon techniques, sealing the trachea or space where internal pressure fluctuates periodically presents particular challenges, such as with the trachea or esophagus. Both structures experience continuous, periodic pressure fluctuations within the chest caused by the patient's own breathing. Regardless of whether the patient is using unassisted or mechanical ventilation, the resulting chest pressure corresponds to the filling pressure of the cuff that seals the trachea.

[0008] If, during a patient's inspiration, the pressure in the chest cavity decreases, this temporary pressure reduction is transmitted to the tracheal and esophageal walls, which in turn leads to a decrease in pressure within the corresponding balloon structures located in the trachea or esophagus. As the tracheal or esophageal walls relax, the cross-sectional area of ​​the terminal channel expands synchronously, resulting in increased secretions and fluid passing through during the expansion phase. This can cause the balloon to completely lose its seal, leading to embolism.

[0009] Badenhorst and his colleagues have noted a specific association between the endotracheal tube cuff and the patient's work of breathing [“Changes in cuff pressure during respiratory support”, CH, Badenhorst, Critical Care Mediane 1987, 15;4, 300-302]. Badenhorst described the cuff pressure values ​​for each patient, starting from approximately 20 mbar and progressing into the subatmospheric range, generally following the intrathoracic pressure values ​​in the chest of a breathing patient.

[0010] In current literature on the sealing properties of endotracheal tube cuffs with dimensional redundancy, the ability of specific cuff types to ensure effective sealing against secretions is determined on static observation models. Accordingly, for example, in an experiment conducted by Bassi et al. [“An in vitro study to assess determinant features associated with fluid sealing in the design of endotracheal tube cuffs and exerted tracheal pressures”; Bassi et al.; Critical care Mediane, 2013; 41:518-526], different endotracheal tubes were inserted into a rigid tube, and subsequently, a water column was installed above the endotracheal tube cuff under filling pressure. For conventional PVC-based cuff types, at the recommended filling pressure of 30 mbar, the leakage determined in the static model was in the range of a few milliliters per minute. Only PUR-based cuff types with extremely thin walls achieved a reliable seal even at filling pressures reduced to 15 mbar. However, at filling pressures below 15 mbar, even PUR balloons with a wall thickness of less than 20 μm begin to expand in the channel-like morphology used to guide secretions. In this case, like the much thicker PVC-Cuff, the cross-section of the small channel from the corresponding indented blind end to its base opens in a drop-like manner, and eventually more secretions and fluids can pass through.

[0011] In summary, static models cannot record the periodic fluctuations in the tracheal cross-sectional area as scalable coefficients. Therefore, static models are unsuitable for reflecting the clinically effective quality of balloon-based tracheal seals under pressure fluctuations. Summary of the Invention

[0012] The purpose of this invention is to provide a novel type of Cuff structure that improves the sealing performance of a balloon assembly under conditions where the balloon filling pressure fluctuates periodically in sync with the organ, ensuring efficient sealing characteristics even when the balloon filling pressure fluctuates continuously with a pressure range from 30 to 5 mbar.

[0013] Within the scope of similar balloon-like structures, the solution of the present invention to achieve the above-mentioned objective is that the balloon is composed of a multilayer balloon film material, wherein at least one layer is composed of elastically deformable polyurethane (PUR), and at least another layer is composed of a non-elastic material such as polyvinyl chloride (PVC), wherein the at least one PUR layer is composed of a thermoplastic PUR type having a water absorption rate of 5% or less according to DIN ISO 62, preferably having a water absorption rate of 2% or less according to DIN ISO 62.

[0014] Therefore, this invention describes a solution for improving the sealing properties of a soft, membrane-like balloon that performs sealing and / or packing functions, the balloon being inserted into an organ or body cavity capable of independent or passive movement, and permanently positioned therein, even when the internal pressure and / or shape of the space within the organ varies intermittently, continuously, or particularly periodically. The balloon of this invention has a specific multi-layered composite structure consisting of layers of inelastically deformable material and layers of elastically deformable material.

[0015] The balloon membrane material comprises one or more layers of elastically deformable material and one or more layers of plastically deformable inelastic material, wherein the inelastic layer has a counteracting effect on the straightening properties of the elastic layer when the balloon membrane material is folded or bent in a planar manner.

[0016] For balloon assemblies with corresponding multi-layered structures that form folded indentations in situ during placement and application of filling pressure, the straightening and opening characteristics of the perforated or channel-like cross-section are reduced by using a material composite containing a non-elastic material. This results in a reduction in the overall cross-sectional area of ​​the guiding secretion at the terminal end, and a reduction in the degree of fluctuation, compared to a single-layer balloon sheath with the same wall thickness made of an elastic material such as PUR, under conditions of intermittent or periodic fluctuations in balloon filling pressure. Particularly preferably, the wall thickness of the inserted PUR layer is reduced to the smallest possible proportion of the total wall thickness of the balloon sheath.

[0017] If a balloon is formed using a pre-manufactured multilayer tubular material via blow molding, a certain proportion of the PUR layer plays a stabilizing role during the molding process. This ensures good symmetry of the balloon body even when the walls of the formed balloon are extremely thin. The tubular material to be formed gradually transitions from a uniformly formed main axis shape to a uniformly formed spherical balloon shape, which ultimately expands into a bubble shape. Based on the elastic properties of PUR, in addition to uniform symmetry, balloon assemblies with extremely small total wall thicknesses (e.g., in the range of 5 to 20 micrometers) can be consistently molded with high quality. Furthermore, in applications where the working filling pressure is temporarily and permanently exceeded, the balloon assembly exhibits high mechanical load capacity, puncture resistance, and generally excellent shape stability.

[0018] Furthermore, by combining one or more PVC-based material layers with a PUR layer that mechanically stabilizes the balloon body according to the present invention, it is also helpful to reduce the water molecule permeation effect typical of PUR. Combining a PVC layer, which has far superior barrier properties against polar substances compared to PUR, with a water-permeable PUR layer is particularly effective in reducing water condensation and accumulation within the balloon.

[0019] To minimize the total wall thickness of the multilayered balloon membrane of this invention, i.e., keeping it within the range of 5 to 30 micrometers, this invention proposes that the type of PUR used has the following characteristics: the balloon wall has a minimal tendency to swell due to the absorption of water molecules. Such swelling effects are known, particularly with non-thermoplastic polyurethanes. Therefore, this invention preferably uses a thermoplastic PUR type with a water absorption rate of less than 4%, preferably less than 2%, according to DIN ISO 62 in an exposed aquatic environment, such as the "Pellethane 2363" product series from Lubrizol Inc. or the "Elastollan 1100" product series from BASF AG. Attached Figure Description

[0020] For further details regarding the features, characteristics, advantages, and effects of this invention, please refer to the following description of several preferred embodiments of the invention in conjunction with the accompanying drawings. Wherein: Figure 1 This is a schematic diagram of the balloon sleeve of the present invention, which is composed of two material layers; Figure 2a For sealed and / or packed balloons with dimensional redundancy in circumference, a transverse cross-sectional view of a channel-like morphology for guiding secretions produced in a lumen smaller than that of a balloon. Figure 2b This shows the corresponding channel-like morphology that increases in a droplet shape when the filling pressure decreases and opens in a U-shape to guide secretions when the filling pressure decreases further. Figure 3 This is a schematic diagram of an endotracheal tube cuff, in which the channel-like shape of the balloon body spans from one end to the other. Figure 4 A two-layer embodiment of the balloon wall is shown, wherein a load-bearing PUR layer is combined with a water vapor barrier layer made of PVDC. Figure 5 A three-layer embodiment of the balloon wall is shown, wherein a load-bearing PUR layer is combined with a central barrier layer composed of PVDC and / or EVOH, and with a PVC layer that weakens the elastic straightening properties of the PUR; and Figure 6 A quantitative comparison of two balloon types formed from elastic PUR, one of which is combined with a PVC layer that modifies the elastic properties of the PUR. Detailed Implementation

[0021] Figure 1 The exemplary two-layer structure of the balloon wall 1 according to the invention is shown in an illustrative embodiment, wherein the outer material layer 2 facing the corresponding lumen or cavity is made of thermoplastic PUR (Elastollan 1100) with a Shore hardness of 90 A and has a wall thickness of 5 to 10 micrometers occupying a certain proportion. Preferably, the material layer 3 facing the inner cavity of the balloon 12 is made of PVC with a Shore hardness of 70 A and has a wall thickness of 15 to 20 micrometers occupying a certain proportion. Preferably, the two polymers are manufactured by a co-extrusion process in a direct planar connection, i.e., without an adhesive interlayer, to fix them to each other. The PVC layer with a thickness of 15 to 20 micrometers, on the one hand, suppresses the elastic straightening of the PUR layer occupying a certain proportion in a perforated form by reducing the speed and degree of straightening. On the other hand, the PVC layer occupying a certain proportion reduces the possibility of polar substances passing through or migrating through the PUR / PVC layer combination, thereby reducing the undesirable condensation and accumulation effects of liquid, especially water, in the inner cavity of the balloon.

[0022] In this invention, the wall layer composed of PVC and PUR can also be arranged in the layered composite body with the PVC layer located on the outside of the balloon.

[0023] In addition to a two-layer balloon wall, a three-layer implementation can also be used, where the PUR layer is preferably sandwiched between two PVC layers. With a total wall thickness of 30 micrometers, the layer distribution can be, for example, 12 μm PVC on the outer side, 6 μm PUR in the center, and 12 μm PVC on the outer side. This implementation is particularly helpful in limiting the undesirable migration effects of polar substances such as water.

[0024] Figure 2aThis is a cross-sectional schematic diagram of an indentation 4 used to guide secretions, when a sealed and / or packed balloon with dimensional redundancy (i.e., oversized) is placed in a lumen or space smaller than that of a balloon with redundant dimensions, resulting in a folded structure due to the indentation of the excess balloon wall. This is particularly noticeable when the filling pressure within the balloon changes periodically, resulting in a typical spoke-like arrangement of such indentations pointing from the circumference to the center during application.

[0025] The indentation has a sheet-like, planar closed portion 5, and an eyelet-like morphology 8 is formed at the blind end of each indentation pointing towards the center of the balloon. Within the area of ​​the formed eyelet, the wall of the balloon sheath is folded 180 degrees, where the elastic straightening properties of the PUR layer integrated into the wall significantly open the eyelet-like morphology. Based on the cross-sectional dimensions of the corresponding eyelet-like morphology, and by minimizing or avoiding periodic abrupt changes in the orifice's diameter, an effective sealing effect of the balloon is achieved at specific points in time. Based on capillary effect, the small cross-sectional area of ​​the eyelet inhibits the flow of secretions within the eyelet, even causing complete stagnation of secretions or the contents of the eyelet. The inhibitory effect on the free flow of secretions is lost as the cross-sectional area of ​​the eyelet gradually expands or increases.

[0026] In addition to the property of elastically straightening the balloon wall that is folded in a perforated shape, the cross-sectional area of ​​the perforated shape 6 related to sealing is determined by the current filling pressure in the balloon, which is applied in particular to the two wall layers 5a and 5b of the tabular portion 5 of the indentation 4 and presses these wall layers planarly against each other in a sealing closure, wherein an open lumen is maintained in the folded area of ​​these two wall layers, i.e. at the blind end of the relevant indentation.

[0027] The total wall thickness of the balloon according to the present invention should preferably not exceed 30 μm. In a preferred embodiment of the balloon, the ratio of the wall thickness occupied by the PUR layer to the wall thickness occupied by the PVC layer is between 1:2 and 1:4, preferably 1:3.

[0028] For example, as Figure 1 For the specific layer combination shown, if the filling pressure in the balloon fluctuates between 30 and 5 mbar due to the patient's own breathing, it will result in an increase of 10% to 25% in the cross-sectional area of ​​the orifice that determines the balloon's sealing effect, but usually will not exceed 20%. At a common filling pressure of 30 mbar, the maximum orifice diameter of the balloon manufactured according to the present invention, inside the corresponding orifice shape, is about 30 to 120 μm, preferably about 40 to 80 μm.

[0029] When the balloon filling pressure fluctuates periodically, for example, at a rate of 20 changes per minute, and the pressure amplitude of the pressure limit value is between 30 and 5 mbar, the sealing properties of the balloon of the present invention are maintained to the greatest extent, for example, when specifically applied to the sealing of organ secretions. The pump-like effect, synchronously following the patient's own breathing and acting periodically on the perforated morphology 6 or on the channel formed by the perforations, as described in medical literature for PVC-based single-layer thick-walled cuffs with a wall thickness of 70 to 120 micrometers, is largely absent in the endotracheal tube cuff implemented according to the present invention.

[0030] Figure 2b Showing with Figure 2a Corresponding to, in the same position as Figure 2a Compared to the perforated shape 6 under reduced filling pressure, if the filling pressure is below a certain critical sealing filling pressure D1, the entry region 7 located at the base of the recess 4 begins to open, and the perforated shape 6 expands, gradually extending from the inner blind end of the recess towards the outer base of the recess. The tabular sealing closure segment 5 of the recess shortens accordingly. When the filling pressure is further reduced to a value D2, the tabular segment 5 fully opens, and the recess transitions into a planar open U-shape.

[0031] Take, for example, a cylindrical sealing balloon used as a endotracheal tube cuff to seal secretions. Figure 3 The schematic diagram illustrates a channel-like shape 8, which originates from an eyelet-like folded shape 6 on a corresponding indented blind end. This channel-like shape extends continuously from one end 9 of the balloon cylinder to the opposite end, or, in many cases, is oriented approximately parallel to the cylindrical axis of the balloon under periodically varying filling pressures. This allows leakage of fluid or secretions from one end of the patient's lumen or interior to the other within the balloon, which functions as a sealing or space-filling tamponade.

[0032] Figure 4 A particular two-layer balloon wall embodiment is shown, wherein a balloon-stabilizing PUR layer 2 is combined with a water vapor-blocking and airtight barrier layer 10 made of PVDC. The PVDC layer 10 can be oriented towards either the outer or inner side of the balloon. PVDC provides highly efficient waterproofing and airtightness even with an extremely thin layer thickness. Therefore, this proposed combination lays the foundation for manufacturing a balloon with a particularly advantageous total wall thickness in the range of 10 to 15 micrometers, which helps to achieve the smallest possible or as constant as possible, non-alternating cross-sectional area of ​​the perforation morphology 6. The thickness of the PUR layer 2 is, for example, 5 micrometers, while the thickness of the PVDC layer 10 is, for example, 5 to 10 micrometers.

[0033] Figure 5 A particular three-layer embodiment of the balloon wall is shown, wherein an elastic PUR layer 2 is combined with a centrally located, airtight, water vapor-blocking barrier layer 10 (e.g., made of PVDC or alternatively of EVOH), and a layer 3, preferably made of PVC and having a low Shore hardness, which suppresses the elastic straightening properties of the PUR according to the invention. Wherein, in the case of a total wall thickness of, for example, 25 micrometers, the thickness of the PUR layer 2 is, for example, 5 micrometers, the thickness of the airtight, water vapor-blocking barrier layer 10 made of PVDC is, for example, 5 micrometers, and the thickness of the suppression layer 3 made of, for example, PVC is 15 micrometers.

[0034] Figure 6 Combining two graphs, 11 and 12, the effect of the filling pressure within the balloon lumen on the sealing effect of the cross-sectional area of ​​the perforated morphology 6 in relation to the sealing or plugging effect of the catheter or device is quantitatively shown. In a comparative approximation, a single-layer balloon (15 micrometers wall thickness, made of "Elastollan 1190A" material) with dimensional redundancy, manufactured from PUR and forming a radially inward-curving residual balloon sheath, according to graph 11, is compared with a double-layer balloon (consisting of a combination of PUR and PVC layers according to the invention, with a total wall thickness of 20 micrometers, as shown in graph 12) made of a double-layer material (according to the invention, consisting of a PUR layer and a PVC layer, with a total wall thickness of 20 micrometers, as shown in graph 12). Figure 1 A comparison is made with a redundant balloon 13 (as illustrated in the process description). With approximately 20 periodic fluctuations per minute, each within the range of 30 mbar to 15 mbar, both balloon types exhibit fairly efficient sealing, nearly achieving a complete seal. However, when the low values ​​of the pressure fluctuations fall within the range of 15 to 5 mbar, the two curves diverge, with the perforation cross-sectional area in scheme 11 increasing by approximately 10 to 25% compared to schemes 12 and 13. For the single-layer balloon according to curve 11, the sealing effect is completely lost in the pressure range below 5 mbar, while for the multi-layer balloons 12 and 13 according to the invention, composed of a PUR layer and a PVC layer, this condition only occurs below approximately 3 mbar.

[0035] Appendix Label Table 1. Balloon wall 2 Material layer 3 Material layer 4. Inward 5. Splice-like parts 6-hole eye-like morphology 7. Enter the area 8-channel morphology 9 end sides 10 Barrier Layers 11. Curve Graph 12. Curve graph 13 Balloon sleeves D1 pressure value D2 pressure value U-shaped

Claims

1. A balloon-like structure (13), particularly as a component of a conduit, for positioning in a manner within a cavity, such as a lumen or other cavity, in the body of a human or animal, such that the cavity is filled as completely as possible, i.e., with no remaining space, but in this case, the cavity substantially maintains its shape or is not deformed by the balloon body (13), characterized in that, The balloon (13) is made of a multilayer balloon film material, wherein at least one layer (2) is made of elastically deformable polyurethane (PUR) and at least another layer (3) is made of a non-elastic material such as polyvinyl chloride (PVC), wherein the at least one PUR layer (2) is made of a thermoplastic PUR type having a water absorption rate of 5% or less according to DIN ISO 62, preferably having a water absorption rate of 2% or less according to DIN ISO 62.

2. The spherical structure (13) according to claim 1, characterized in that, When the residual balloon body, which is formed by excess balloon material along the circumference of the balloon, is placed in situ, an indentation (8) is formed that is usually embedded inside the balloon body.

3. The spherical structure (13) according to claim 2, characterized in that, The indentation (8) that is embedded inside the balloon has a folded shape (6) with a hole-like cross-section. The folded shape preferably extends or continues as a channel-like shape (9) along the longitudinal direction of the balloon (13), that is, between the distal side and the proximal side (9) of the balloon.

4. The spherical structure (13) according to claim 3, characterized in that, When the filling pressure of the balloon (13) is 30 mbar, the folded shape (6) with a perforated cross-section that preferably extends or continues as a channel-like shape (9) along the longitudinal direction of the balloon (13) has an opening diameter between 30 μm and 120 μm, preferably between 40 μm and 80 μm.

5. The spherical structure (13) according to claim 3, characterized in that, Due to its combination with at least one layer (3) made of a non-elastic material, such as PVC, the opening diameter of the perforated or channel-like morphology (6, 9) is reduced compared to the opening diameter of the perforated or channel-like morphology (6, 9) of a pure PUR layer (2) having the same material type and layer thickness; wherein the at least one layer (3) made of a non-elastic material, such as PVC, has plastic, non-elastic properties such that in the event of in-situ changes in the filling pressure of the balloon (13), the planar deformation, bending or curling of the layer has an inhibitory effect on the opening movement characteristics of the perforated or channel-like morphology (8); preferably, in the event of a temporary or periodically fluctuating pressure drop in the balloon, the elastic opening or expansion of the perforation or channel is slowed down by combining at least one PUR layer (2) with at least one layer (3) made of a non-elastic material such as PVC.

6. The spherical structure (13) according to claim 3, characterized in that, By combining at least one PUR layer (2) with at least one layer (3) made of a non-elastic material such as PVC, the elastic straightening effect in the region of the perforated or channel-like folded morphology (6, 9) is reduced in a certain way, such that the cross-sectional area of ​​the perforated and channel-like structures (6, 9) used to guide secretions is reduced compared to a single-layer elastic balloon membrane (2) made of PUR alone, and is also reduced under periodic fluctuations in balloon filling pressure.

7. The spherical structure (13) according to claim 1, characterized in that, The ratio of the wall thickness of at least one PUR layer (2) to the wall thickness of at least one layer (3) made of a non-elastic material such as PVC is between 1:1 and 1:5; wherein, preferably, at least one layer (3) is made of a non-elastic material made of polyvinylidene chloride (PVDC) or ethylene-vinyl alcohol copolymer (EVOH).

8. The spherical structure (13) according to claim 1, characterized in that, Between the elastically deformable PUR layer (2) and the non-elastically deformable layer (3) made of, for example, PVC, a barrier layer (10) preferably made of PVDC or EVOH that is airtight and / or blocks water vapor is provided.

9. The spherical structure (13) according to claim 8, characterized in that, The wall thickness of the non-elastically deformable layer (3) made of, for example, PVC, is greater than the wall thickness of the elastically deformable PUR layer (2) and / or greater than the wall thickness of the airtight and / or water vapor-blocking barrier layer (10) preferably made of PVDC or EVOH; preferably, the ratio of the wall thickness of the airtight and / or water vapor-blocking barrier layer (10) made of PVDC or EVOH to the wall thickness of the non-elastically deformable layer (3) made of, for example, PVC, is between 1:1 and 1:5, preferably between 1:2 and 1:4, and particularly, for example, 1:

3.

10. The spherical structure (13) according to claim 8, characterized in that, The connection of the multiple layers (2, 3, 10) of the balloon sleeve (13) is established by co-extruding the layers (2, 3, 10), or the balloon sleeve (13) is manufactured by blow molding a multi-layer extruded hose blank.

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