MINIMALLY INVASIVE CATHETER

Abstract

Minimally invasive catheter relates to the field of eversible catheters. It is primarily intended for use as a urinary catheter, but is also usable in other fields. As a urinary catheter this minimally invasive catheter 1 used as an indwelling or intermittent catheter with transurethral or suprapubic approach. This catheter has specific technical solution for eversible motion where tubular membrane 2, attached between distal part 36a of the handle 36 and distal part 3a of the inner tube 3, can in one case free slide between these two parts and in another be fixed to form hermetically sealed space 14. Free sliding of membrane ensures eversible principle of motion during placement and withdrawal of the catheter 1. Fixation of membrane allows a formation of hermetically sealed space 14 with fluid to make catheter surface smoother and softer, and a balloon 33 to hold catheter 1 in place for prolonged period of time. Thus, present invention provides a urinary catheter that enables the reduced incidence of complications arising due to its application.

Claims

1. A catheter (1) comprising a handle (36) having a hole (13), a tubular membrane (2) having a part which is partially enlarged for forming a balloon (33), inner tube (3) being attached to the handle (36) and having body (3b) and the distal part (3a) of the inner tube (3), the distal part (3a) containing lateral holes (11a, 11b), an outer tube (4) having a rounded tip (5), the proximal opening (10) of the catheter (1) that is attachable to bags for holding body fluids characterized in that the handle (36) comprises a proximal part (36c) of the handle (36), a medial part (36b) of the handle (36) and a distal part (36a) of the handle (36), wherein the proximal part (36c) of the handle (36) is detachably connected with the medial part (36b) of the handle (36) and medial part (36b) of the handle (36) is detachably connected with the distal part (36a) of the handle (36), the medial part (36b) of the handle (36) further comprising nut (7), said nut (7) fitting with a thread (26) of the distal part (36a) of the handle (36), and proximal part (36c) of the handle (36) comprising nut (9), said nut (9) fitting with a thread (25) of the medial part (36b) of the handle (36), the tubular membrane (2) being slidable between the distal part (36a) of the handle (36) and the distal part (3a) of the inner tube (3) through the outer tube 4, the outer tube (4) is in fixed connection to the medial part (36b) of the handle (36) and the body (3b) of the inner tube (3) is mounted to the proximal part (36c) of the handle (36), the distal part (36a) of the handle (36) further comprising proximal membrane attachment (22), the inner tube (3) further comprising a distal membrane attachment (21) for tight engagement of the tubular membrane (2) with the distal part (3a) of the inner tube (3), the diameter of the distal part (3a) of the inner tube (3) being smaller than the diameter of the body (3b) of the inner tube (3), the outer tube (4) further having the lateral channels (15a, 15b) fitting with protrusions (20a, 20b) of the distal part (36a) of the handle (36), respectively, for sliding of the distal part (36a) of the handle (36) along the outer tube (4), the body (3b) of the inner tube (3) having lateral channels (19a, 19b) fitting with protrusions (24a, 24b) of the medial part (36b) of the handle (36), respectively, said distal part (3a) of the inner tube (3) having hole (16) at the end of distal part (3a) of the inner tube (3) and two lateral holes (11a, 11b) and between the outer tube (4) and tubular membrane (2) is embedded hermetically sealed space (14).

2. The catheter (1) according to patent claim 1, characterized in that the tubular membrane (2) and distal part (3a) of the inner tube (3) are enclosed inside the outer tube (4).

3. The catheter (1) according to patent claim 1, characterized in that the nut (7) of the medial part (36b) of the handle (36) and nut (9) of the proximal part (36c) of the handle (36) are screwed for tight engagement of the proximal part (36c) of the handle (36), the medial part (36b) of the handle (36) and the distal part (36a) of the handle (36).

4. The catheter (1) according to patent claim 1, characterized in that the hermetically sealed space (14) is inflated with fluid by injection of the fluid through the hole (13) of the handle (36) and a diameter of hermetically sealed space (14) is larger than a diameter of the rounded tip (5) of the outer tube (4).

5. The catheter (1) according to patent claim 1, characterized in that the hole (13) of the handle (36) is arranged on the distal part (36a) of the handle (36) or on the medial part (36b) of the handle (36) or on the proximal part (36c) of the handle (36).

6. The catheter (1) according to patent claim 1, characterized in that the tubular membrane (2) is coated.

7. The catheter (1) according to patent claim 1, characterized in that the tubular membrane (2) contains the inner layer (30) and the outer layer (31).

8. The catheter (1) according to patent claim 7, characterized in that the inner layer (30) and the outer layer (31) are engaged by the distal membrane attachment (21) and the proximal membrane attachment (22) and are also tightly engaged between themselves along their entire length, except within the balloon (33) where they are apart from each other.

9. The catheter (1) according to patent claim 7, characterised in that the inner layer (30) of tubular membrane (2) contains holes (32) within the balloon (33).

10. The catheter (1) according to patent claim 7, characterized in that the balloon (33) encloses the tubular membrane (2) containing the inner layer (30) and the outer layer (31).

11. The catheter (1) according to patent claim 7, characterized in that the inner layer (30) of tubular membrane (2) is connected with the outer layer (31) of tubular membrane (2) by the tight attachment (35) and distal membrane attachment (21).

12. The catheter (1) according to patent claim 1, characterized in that the outer tube (4) contains apertures (34).

Description

BRIEF DESCRIPTION OF DRAWINGS

[0028] FIG. 1 is a perspective view of the catheter.

[0029] FIG. 2 is a top view of the catheter along main axis with represented position of longitudinal cross-section line A-A and positions of transversal cross-section lines B-B, C-C, D-D.

[0030] FIG. 3 is a view from the side of the catheter.

[0031] FIG. 4 is a transversal cross-sectional view along line B-B.

[0032] FIG. 5 is a transversal cross-sectional view along line C-C.

[0033] FIG. 6 is a transversal cross-sectional view along line D-D.

[0034] FIG. 7 is a longitudinal cross-sectional view along line A-A.

[0035] FIG. 8 is a perspective view of the catheter in a disassembled configuration.

[0036] FIG. 9 is a view of detail A of the catheter.

[0037] FIG. 10 is an exploded view of the proximal part, medial part and distal part of the handle.

[0038] FIG. 11 shows the catheter with its internal parts prior to placement.

[0039] FIG. 12 shows the catheter with its internal parts during insertion through urethra into the urinary bladder.

[0040] FIG. 13 shows the catheter with its internal parts which is placed in the urinary bladder.

[0041] FIG. 14 shows the catheter with its internal parts which is fixed in place with inflated balloon.

[0042] FIG. 15 shows the catheter with its internal parts during the initiation of the catheter removal.

[0043] FIG. 16 shows the catheter with its internal parts during removal progression.

[0044] FIG. 17 is a tubular membrane with an enlargement of the tubular membrane in the form of a balloon.

[0045] FIG. 18 is a modification 1 of the tubular membrane.

[0046] FIG. 19 is a modification 2 of the tubular membrane.

[0047] FIG. 20 is a perspective view of the modification 1 of the outer tube.

[0048] FIG. 21 shows the detail B of modification 1 of the outer tube.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0049] The outer tube 4 and the inner tube 3 are sufficiently flexible for easily passing curvatures of the urethra.

[0050] The catheter according to the present invention includes a distal part 36a of the handle 36, tubular membrane 2, distal part 3a of the inner tube 3, outer tube 4, rounded tip 5 of the outer tube 4, medial part 36b of the handle 36, nut 7 of the medial part 36b of the handle 36, proximal part 36c of the handle 36, nut 9 of the proximal part 36c of the handle 36, the proximal opening 10 of the catheter 1 that is attachable to urine bags, or used for access to the urinary tract or other body cavities.

[0051] The distal part 3a of the inner tube 3 has lateral holes 11a, 11b for urine flow. The tubular membrane 2 has an enlargement in the form of a balloon 33 next to the distal part 3a of the inner tube 3. When the fluid is injected through the hole 13 of the handle 36, said enlargement of the tubular membrane 2 forms a balloon 33 at the end of the catheter 1, as a part of hermetically sealed space 14 which may be filled with fluid. Hole 13 of the handle 36 can be arranged on the distal part 36a of the handle 36, the medial part 36b of the handle 36 or on the proximal part 36c of the handle 36.

[0052] As shown in FIG. 3, the lateral channels 15a, 15b of the outer tube 4 must be placed in the position under the hole 13 of the handle 36, during the removal of the fluid from hermetically sealed space 14.The lateral channels 15a, 15b of the outer tube 4 are essential for efficient fluid flow from the balloon 33 through hole 13, when the hole 13 is located on the distal part 36a of the handle 36 or on the medial part 36b of the handle 36 during the removal of the fluid from the hermetically sealed space 14. Additionally, two lateral channels 19a, 19b of the inner tube 3 are essential for efficient fluid flow from the balloon 33 through hole 13, when the hole 13 is located on the proximal part 36c of the handle 36. This is important because the tubular membrane 2 should not get completely attached to the surface of the outer tube 4 which would block the flow of the fluid.

[0053] The distal part 3a of the inner tube 3 has a hole 16 at the end of distal part 3a of the inner tube 3 and two lateral holes 11a, 11b (FIG. 4). The distal part 3a of the inner tube 3 must have more than one hole, in order to prevent urine flow obstruction and pseudopolyps making. When catheter is placed within bladder, the lateral holes lateral holes 11a, 11b of the inner tube 3 should not be in contact with the membrane, because that would block urine flow through catheter.

[0054] In one embodiment, the hermetically sealed space 14 is inflated with fluid. This fluid layer between the outer tube 4 and tubular membrane 2 provides soft and smooth catheter surface in order to amortize the forces transmitted from the catheter to the epithelium and prevent biofilm making. Moreover, the fluid layer improves fitting of catheter to urethra surfaces and prevents side flow of urine between urethra walls and catheter. It is important to notice that inner lumen 17 of the outer tube 4 is circular, and body 3b of the inner tube 3 may easily slide through it.

[0055] The body 3b of the inner tube 3 can slide through medial part 36b of the handle 36, but rotatory movement is blocked because body 3b of the inner tube 3 has two lateral channels 19a, 19b that fit with protrusions 24a, 24b of the medial part 36b of the handle 36 thus preventing the rotation of inner tube 3.

[0056] The outer tube 4 is in fixed connection with the medial part 36b of the handle 36. Body 3b of the inner tube 3 is in fixed connection to the proximal part 36c of the handle 36.

[0057] A distal membrane attachment 21 is placed between the body 3b of the inner tube 3 and the distal part 3a of the inner tube 3. The diameter of the distal part 3a of the inner tube 3 is smaller than the diameter of the body 3b of the inner tube 3. A proximal membrane attachment 22 is placed on the distal part 36a of the handle 36. It is important to notice that connections between distal part 36a of the handle 36, tubular membrane 2, body 3b of the inner tube 3 and proximal part 36c of the handle 36 are fixed and hermetically sealed. In cases of prolonged use, the catheter must be fixed in a way that allows positioning at the same place in the urethra for the prolonged period of time. When the catheter is placed in urinary bladder, as shown in FIGS. 13 and 14, the nut 7 of the medial part 36b of the handle 36 and the nut 9 of the proximal part 36c of the handle 36 are screwed, and proximal part 36c of the handle 36 is tightly engaged with the medial part 36b of the handle 36 and distal part 36a of the handle 36. As a result, the hermetically sealed space 14 is enclosed by surfaces of distal part 36a of the handle 36, tubular membrane 2, body 3b of the inner tube 3, proximal part 36c of the handle 36 and medial part 36b of the handle 36. Through the hole 13 of the distal part 36a of the handle 36 (shown in FIG. 3), fluid can be injected into hermetically sealed space 14 to expand the tubular membrane 2 having balloon 33 which holds the catheter in place for prolonged period of time.

[0058] The lateral channels 15a, 15b of the outer tube 4 fit with protrusions 20a, 20b of the distal part 36a of the handle 36, respectively, which allows sliding of the distal part 36a of the handle 36 along the outer tube 4, as shown by the arrow 40 in FIG. 8, without rotation around longitudinal axis of the outer tube 4.

[0059] Tubular membrane 2 from the distal membrane attachment 21 passes through the lumen 23 of the medial part 36b of the handle 36 and is attached to the distal part 36a of the handle 36.

[0060] As shown in FIG. 9, body 3b of the inner tube 3 contains lateral channels 19a, 19b of the inner tube 3 which fit with protrusions 24a, 24b of the medial part 36b of the handle 36, respectively. These “channels and protrusions”, allow longitudinal sliding of the body 3b of the inner tube 3 as indicates an arrow 41 in FIG. 8. In addition, “channels and protrusions”, prevent the rotational movement of the body 3b of the inner tube 3.

[0061] It is important to note that theet 20a, 20b are positioned on the distal part 36a of the handle 36, while theet 24a, 24b are positioned on the medial part 36b of the handle 36.

[0062] Proximal part 36c of the handle 36 contains the nut 9 which fits with thread 25 of the medial part 36b of the handle 36 and forms hermetically fitted junction between these two parts. The nut 9 of the proximal part 36c of the handle 36, can freely rotate in the direction as shown by the arrow 42 in FIG. 8. This provides tight engagement between proximal part 36c of the handle 36 and medial part 36b of the handle 36.

[0063] Similarly, the nut 7 of the medial part 36b of the handle 36, is freely rotatable in the direction as shown by the arrow 43 in FIG. 8, and fits with a thread 26 of the distal part 36a of the handle 36 thus providing tight engagement between medial part 36b of the handle 36 and the distal part 36a of the handle 36.

[0064] Tight engagements of the lateral parts are important for prevention of twisting of the catheter during nuts screwing. Thus, lateral parts 27a, 27b of the proximal part 36c of the handle 36 fit with lateral parts 28a, 28b of medial part 36b of the handle 36, respectively, and lateral parts 28c, 28d of medial part 36b of the handle 36 fit with lateral parts 29a, 29b of distal part 36a of the handle 36, respectively. This prevents rotation of the proximal part 36c, medial part 36b and distal part 36a of the handle 36 during rotation of the nuts 7, 9.

[0065] As shown in FIG. 11, prior to placement of the catheter 1, tubular membrane 2 and distal part 3a of the inner tube 3, i.e. the parts of the catheter 1 that are in direct contact with urethra and urinary bladder, are protected from the contamination with bacteria from external environment, by being enclosed inside the outer tube 4. This prevents contamination of these parts during preparation of the catheter insertion (hygienic procedures). The catheter 1, according to the present invention, can simply be operated with one hand of the medical practitioner placed on distal part 36a of the handle 36 as well as on the tissue which surrounds the meatus of the urethra, while the other hand is used to push the medial part 36b of the handle 36 or the outer tube 4. As pressure is applied in the direction as indicated by the arrow 44 as shown in FIG. 11, the forward end of the tubular membrane 2 unrolls progressively in the direction as indicated by the arrow 45 as shown in FIG. 11 to cover the walls of the urethra U. This “eversible” principle of motion of tubular membrane 2 during catheter 1 insertion prevents transport of bacteria from the region around the meatus of urethra and distal part of urethra to urinary bladder, but also reduces sliding friction, pain and trauma of epithelium of the urethra.

[0066] During unrolling in the direction as indicated by the arrow 45 as shown in FIG. 11, the tubular membrane 2 pulls the body 3b of the inner tube 3 through the outer tube 4 as indicated by the arrow 46 as shown in FIG. 12.

[0067] As shown in FIG. 13, the lengths of the body 3b of the inner tube 3, the outer tube 4 and tubular membrane 2 are sufficient to allow the tubular membrane 2 to cover the walls of the urethra and distal part 3a of inner tube 3 to enter the bladder.

[0068] When the catheter is placed in urinary bladder, as shown in FIG. 13, the nut 7 of the medial part 36b of the handle 36 and the nut 9 of the proximal part 36c of the handle 36 provide tight engagement between proximal part 36c, medial part 36b and distal part 36a of the handle 36. The proximal part 36c of the handle 36 is than tightly engaged with the medial part 36b of the handle 36, and medial part 36b of the handle 36 is tightly engaged with distal part 36a of the handle 36. The tubular membrane 2 encloses the hermetically sealed space 14.

[0069] Prior to removal of the catheter 1 from the urinary bladder, the medical practitioner must remove the fluid from the hermetically sealed space 14 through the hole 13, followed by unscrewing the nut 7 of the medial part 36b of the handle 36 and nut 9 of the proximal part 36c of the handle 36. As a result, the balloon 33 collapses allowing the catheter 1 to be removed (FIG. 15).

[0070] During the removal of the catheter 1, the medical practitioner can easily use the catheter 1 only by one hand holding medial part 36b of the handle 36, while the other hand may pull proximal part 36c of the handle 36 or body 3b of the inner tube 3, in the direction as indicated by the arrow 47 as shown in FIG. 16. By pulling of the inner tube 3, the tubular membrane 2 is drawn together with the exhausted balloon 33 in the direction as indicated by arrows 48 and 49 as shown in FIG. 16. In turn, the tubular membrane progressively uncovers the walls of the urethra, and the outer tube 4 moves in the direction as indicated by the arrow 50 (FIG. 16). During this movement, sliding friction between tubular membrane 2 and urethra is reduced. It is important to notice that this kind of catheter 1 removal prevents the urethral damage usually caused by an incomplete collapse of the balloon. As already noted in the prior art, an incomplete collapse of the balloon, also known as a “creep phenomen” of indwelling catheters, damages the urethra. Overcoming this problem allows also the suprapubic use of catheter 1 according to the present invention.

[0071] The tubular membrane 2 should be made from material with ultrahigh strength characteristic, thin walls and compliance range from 0% to 10%. Preferably, the tubular membrane 2 is coated. FIG. 17 shows distal membrane attachment 21 and proximal membrane attachment 22. The balloon 33 may vary in shape, size, position and number.

[0072] In one embodiment, (Modification 1 of the tubular membrane 2) the tubular membrane 2 is made of two layers. The Inner layer 30 of the tubular membrane 2 is made from material with ultrahigh strength characteristic and low friction rate, thin walls and compliance range from 0% to 10%. The outer layer 31 of tubular membrane 2 is made from elastic material suitable for use in the direct contact with human tissues. These two layers are in connection between distal membrane attachment 21 and proximal membrane attachment 22. In addition, they are tightly engaged along their entire length, except within the balloon 33 where they are apart from each other. The inner layer 30 of tubular membrane 2 contains holes 32 within the balloon 33. Thus, fluid can flow through the holes 32 in both directions, allowing inflating and exhausting the balloon 33.

[0073] In another embodiment, (Modification 2 of the tubular membrane 2) the inner layer 30 of the tubular membrane 2 and the outer layer 31 of tubular membrane 2 are positioned only within the balloon 33. The inner layer 30 of tubular membrane 2 is connected with outer layer 31 of tubular membrane 2 by the tight attachment 35 and distal membrane attachment 21. Inner layer 30 of tubular membrane 2 contains holes 32 within the balloon 33 and fluid can flow through these holes 32 in both directions this enabling the inflating or exhausting the balloon 33.

[0074] In another embodiment, (Modification 1 of the outer tube 4), the outer tube 4 contains apertures 34 of different shapes, which provide flexibility of the tube. Size, shape, position and number of these apertures 34 can be different to ensure flexibility and prevent twisting. Detail B view of the outer tube 4 containing apertures 34 along the walls of the outer tube 4 having lateral channels 15a, 15b of the outer tube 4 is presented in FIG. 21.