Catheter

Abstract

To provide a catheter which allows a transmission cable to be built easily therein.SOLUTION: A catheter 100 comprises a tube 12 having a lumen 15 that communicates with openings 16 and 17 formed at the tip. The tube 12 has cable holding parts 22 and 23 formed within the lumen 15 to hold a transmission cable 32.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to a catheter used through a transmission cable.

Background Art

[0002] Acute kidney injury (AKI), which occurs in 30 - 50% of inpatients in intensive care units, has an adverse effect on the prognosis of patients even when it is mild, and the mortality rate when blood purification is required reaches 60%. In addition, the transition to chronic renal failure is also a problem. AKI is caused in part by hypoxia in the renal medulla, and it is thought that the renal medullary oxygen partial pressure can be estimated by measuring the urinary oxygen partial pressure in the bladder. To measure the oxygen partial pressure in the urine in the bladder, a catheter provided with an oxygen partial pressure measurement sensor to measure the oxygen partial pressure in the bladder or the bladder wall has been proposed. In this type of catheter, in order to measure the oxygen partial pressure, a dedicated transmission cable lumen for the transmission cable is formed separately from the drainage lumen for urine flow in order to pass a transmission cable that connects the sensor body and a device attached to the outside of the catheter. (For example, see Patent Document 1). In this transmission cable lumen, a sensor in which the sensor body and the transmission cable are integrated is inserted into the transmission cable lumen from the proximal end of the catheter, and the sensor body is arranged near the balloon provided at the distal end of the catheter to measure the oxygen partial pressure of the urine flowing in from the distal end hole or side hole of the catheter.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the conventional catheter in which the transmission cable lumen was separately formed, it was difficult to insert the sensor into the transmission cable lumen. More specifically, when incorporating the sensor into the catheter, the rear end portion of the transmission cable was held by hand and inserted from the proximal end of the catheter. However, since the catheter formed of silicone or the like has a high coefficient of friction, it was difficult for the sensor to slide within the transmission cable lumen.

[0005] In addition, since the frictional force was large and it was difficult to slide, it was difficult to align and fix the sensor body at a specific position.

[0006] Furthermore, when aligning the sensor within the catheter, if the transmission cable was forcedly pushed in, there was a risk that the transmission cable made of an optical fiber or the like would break.

[0007] Furthermore, since it was necessary to thicken a part of the tube to form the transmission cable lumen within the tube of the catheter, the flow path area of the urine drainage lumen became small, and the flow rate of urine flowing through the urine drainage lumen decreased.

[0008] An object of the present invention is to solve the problems of the above-described conventional technology and provide a catheter capable of easily incorporating a transmission cable.

Means for Solving the Problems

[0009] The present invention provides a catheter comprising a tube having a lumen formed at the tip and communicating with an opening formed at the tip, wherein the tube is characterized in that a cable holding portion for holding a transmission cable is formed within the lumen.

[0010] In this case, the cable holding part may be formed integrally with the tube. The cable holding part may be formed in a plate shape. The cable holding part may extend along the inner cavity. It may protrude from the inner peripheral surface of the tube such that each of the pair of cable holding parts faces the other. The distance by which one of the cable holding parts protrudes from the inner peripheral surface of the tube and the distance by which the other cable holding part protrudes from the inner peripheral surface of the tube may be the same. The catheter may further include a sensor having the transmission cable, and the distance between the tip of one of the cable holding parts and the tip of the other cable holding part may be smaller than the diameter of the transmission cable.

Advantages of the Invention

[0011] In the present invention, it is possible to provide a catheter into which a transmission cable can be easily incorporated.

Brief Description of the Drawings

[0012]

Figure 1

Figure 2

Figure 3

Figure 4

Embodiments for Carrying Out the Invention

[0013] Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. Fig. 1 shows a side view of the balloon catheter, Fig. 2 shows a cross-sectional view of the balloon catheter with the balloon inflated, Fig. 3 shows a cross-sectional view of the proximal end of the balloon catheter, and Fig. 4 shows a longitudinal sectional view of the tube.

[0014] As shown in FIG. 1, the balloon catheter 100 includes a catheter body 10, a sensor 30, and a fixing portion 40. The fixing portion 40 is attached to the catheter body 10, and the sensor 30 is fixed to the catheter body 10 via the fixing portion 40 to form an integrated product.

[0015] The catheter body 10 is composed of a distal end portion 11, a tube 12, a balloon 13, and a branch portion 14. The distal end portion 11 and the balloon 13 are coupled to the tube 12 on the distal end side of the catheter body 10, while the branch portion 14 is coupled to the tube 12 on the proximal end side of the catheter body 10 and integrally formed.

[0016] The distal end portion 11, the tube 12, the balloon 13, and the branch portion 14 are formed of silicone rubber, but may also be formed of latex, natural rubber, isoprene rubber, thermoplastic resin, for example, PVC and urethane rubber, fluororubber, and fluororesin.

[0017] As shown in FIG. 2, the tube 12 penetrates the balloon 13, and the balloon 13 is provided on the outer periphery near the distal end by adhesion. Further, the distal end portion 11 formed in a cylindrical shape is attached to the end face of the distal end of the tube 12 by adhesion. The tube 12 has a urine drainage lumen (inner cavity) 15 formed along the extending direction of the tube 12 for flowing urine. The external portion communicates with the urine drainage lumen 15 through a distal end hole (opening) 16 and a side hole (opening) 17 formed in the distal end portion 11, and the urine flowing in from the distal end hole 16 and the side hole 17 flows through the urine drainage lumen 15 to the branch portion 14 on the proximal end side.

[0018] A part of the tube 12 is formed with a thick wall, and a balloon lumen 18 for inflating the balloon 13 is formed along the extending direction of the tube 12 in the thick-walled portion. The balloon lumen 18 is fluidly communicated with the inside of the balloon 13 near the distal end, and the balloon 13 is inflated by filling the inside of the balloon 13 with sterilized water supplied from the branch portion 14 on the proximal end side.

[0019] The urine passage lumen 15 is formed to have a substantially circular cross-section, and the balloon lumen 18 is formed to have a circular cross-section smaller than that of the urine passage lumen 15.

[0020] The balloon 13 is formed to be cylindrical when not inflated. The non-inflated portions on the distal end side and the proximal end side of the balloon 13 are formed in a tapered shape, and the outer diameter smoothly decreases toward the distal end and the proximal end. When sterile water is supplied from the branch portion 14 through the balloon lumen 18, the balloon 13 expands into a spherical shape centered on the tube 12 between the distal end side inflation end 13A and the proximal end side inflation end 13B. As a result, the balloon catheter 100 is fixed so that the balloon 13 is caught in the patient's bladder and does not come out.

[0021] As shown in FIG. 3, the branch portion 14 has its distal end side connected to the tube 12, while its proximal end side is divided into three, namely a balloon injection port 19, a transmission cable insertion port 20, and a urine outlet 21.

[0022] The balloon injection port 19 is fluidly connected to the balloon lumen 18 and can be connected to a reservoir (not shown) for injecting sterile water into the balloon lumen 18.

[0023] The transmission cable insertion port 20 extends linearly with respect to the urine passage lumen 15, and the sensor 30 inserted straight into the transmission cable insertion port 20 is inserted straight into the urine passage lumen as it is.

[0024] The urine outlet 21 extends obliquely with respect to the urine passage lumen 15, can be connected to a urine tube (not shown), etc., and is connected to a urine bag or the like through the urine tube.

[0025] The sensor 30 inserted into the transmission cable insertion port 20 includes a sensor main body 31 and a transmission cable 32, as shown in FIG. 2. The sensor 30 according to the present embodiment is an oxygen partial pressure measurement sensor. The sensor main body 31 is an excitation light irradiation unit, the transmission cable 32 is an optical fiber, and the transmission cable 32 is formed of a material that is harder and has a stronger elastic force than the tube 12. A phosphor is applied in the urine drainage lumen 15 of the tube 12, and the light sent from the transmission cable 32 is irradiated from the sensor main body 31 to the phosphor.

[0026] As shown in FIG. 3, the fixing portion 40 is attached to the transmission cable insertion port 20, and the sensor 30 is fixed to the tube 12 via the fixing portion 40 that fixes the transmission cable 32.

[0027] The fixing portion 40 includes a fixing portion main body 41, a fixing portion cap 42, and a tightening portion 43. The tightening portion 43 has an annular shape with a through hole 43A formed at the center through which the transmission cable 32 can pass. The tightening portion 43 is sandwiched between the fixing portion main body 41 and the fixing portion cap 42 screwed into the fixing portion main body 41. When the fixing portion cap 42 is screwed into the fixing portion main body 41, the tightening portion 43 is crushed and the diameter of the through hole 43A becomes smaller. Thereby, the tightening portion 43 tightens the transmission cable 32 to fix the transmission cable 32.

[0028] As shown in FIG. 4, in the tube 12 according to the present embodiment, a pair of cable holding portions 22, 23 for holding the transmission cable 32 are formed in the urine drainage lumen 15. The cable holding portions 22, 23 are formed integrally with the tube 12 in a plate shape and extend from the distal end side end portion to the proximal end side end portion of the tube 12 along the urine drainage lumen 15.

[0029] The urine drainage lumen 15 is defined by the cable holding portions 22, 23 into a first region A1 having a large flow path area and a second region A2 having a small flow path area, and the transmission cable 32 is accommodated and held in the second region A2.

[0030] Each of the pair of cable holders 22 and 23 protrudes from the inner peripheral surface of the tube 12 so as to face each other. The distance H by which one cable holder 22 and the other cable holder 23 protrude from the inner peripheral surface of the tube 12 is the same.

[0031] The interval S between the cable holder tip 22A of one cable holder 22 and the cable holder tip 23A of the other cable holder 23 is smaller than the diameter D of the transmission cable 32. Thereby, the transmission cable 32 is held so as not to move to the opposite side of the pair of holders 22 and 23. Note that the pair of cable holders 22 and 23 are integrally formed of the same soft material as the tube 12.

[0032] When incorporating the sensor 30 into the tube 12, the sensor 30 is inserted into the second region A2 of the urine drainage lumen 15 from the transmission cable insertion port 20 (see FIG. 3).

[0033] Once the sensor 30 is inserted into the second region A2 of the urine drainage lumen 15, next, the sensor 30 is moved through the second region A2 until the sensor body 31 is positioned near the balloon 13. At this time, since the second region A2 has a sufficiently large flow path cross-section with respect to the sensor body 31 and the transmission cable 32 of the sensor 30, the sensor 30 can easily pass through the second region A2 of the tube 12.

[0034] Once the sensor body 31 is inserted up to the vicinity of the balloon 13, next, the sensor 30 is fixed by the fixing portion 40. Thereby, the transmission cable 32 is held within the second region A2.

[0035] The balloon catheter 100 according to this embodiment includes a tube 12 in which a urine drainage lumen 15 communicating with a tip hole 16 and a side hole 17 formed at the tip is formed. In the tube 12, cable holding portions 22 and 23 for holding a transmission cable 32 are formed in the urine drainage lumen 15. Thereby, the transmission cable 32 can be inserted into the tube 12 with little frictional force generated by passing through the urine drainage lumen 15, and the transmission cable 32 can be held by the cable holding portions 22 and 23 after being inserted into the tube 12. Therefore, the transmission cable 32 can be easily incorporated into the tube 12.

[0036] Also, in the balloon catheter 100, a wide space composed of a first region A1 and a second region A2 is formed around the sensor body 31 and the transmission cable 32. Thereby, when alcohol is applied to the sensor body 31 and the transmission cable 32 in order to reduce the frictional force when inserting into the tube 12, the inserted sensor body 31 and transmission cable 32 are easily in contact with the surrounding air flow. Therefore, after being inserted into the tube 12, the alcohol applied to the sensor body 31 and the transmission cable 32 can be easily dried.

[0037] Furthermore, since there is no need to form a thick portion for forming the transmission cable lumen in the tube, the flow path area of the urine drainage lumen 15 can be increased, and the flow rate of the flowing urine can be increased.

[0038] The present invention has been described based on the embodiments above, but the present invention is not limited thereto. For example, in the above embodiment, the sensor 30 including the irradiation unit and the optical fiber is used, but it is not limited thereto. Any sensor capable of measuring the oxygen partial pressure may be a sensor using other methods.

Explanation of Reference Numerals

[0039] 10... Catheter body 11... Tip portion 12... Tube 13... Balloon 13A…Tip-side expansion end 13B…Base-side expansion end 14…Branching part 15…Urination lumen (inner cavity) 16…Tip hole (opening) 17…Side hole (opening) 18…Balloon lumen 19…Balloon injection port 20…Transmission cable insertion port 21…Urination port 22…Cable holding part 22A…Tip of cable holding part 23…Cable holding part 23A…Tip of cable holding part 30…Sensor 31…Sensor body 32…Transmission cable 34…Mounting part 35…Leg part 40…Fixing part 41…Fixing part body 42…Fixing part cap 43…Tightening part 43A…Through hole 100…Balloon catheter A1…First region A2…Second region D…Diameter H…Distance S…Interval

Claims

1. In a catheter, comprising a tube having a lumen formed therein that communicates with an opening formed at the tip, the catheter is characterized in that a cable holding portion for holding a transmission cable is formed within the lumen.

2. In the catheter according to Claim 1, the catheter is characterized in that the cable holding portion is formed integrally with the tube.

3. In the catheter according to Claim 1, the catheter is characterized in that the cable holding portion is formed in a plate shape.

4. In the catheter according to Claim 1, the catheter is characterized in that the cable holding portion extends along the lumen.

5. In the catheter according to Claim 1, the catheter is characterized in that each of a pair of the cable holding portions projects from the inner peripheral surface of the tube so as to face each other.

6. In the catheter according to Claim 5, the catheter is characterized in that the distance by which one of the cable holding portions projects from the inner peripheral surface of the tube is the same as the distance by which the other cable holding portion projects from the inner peripheral surface of the tube.

7. In the catheter according to Claim 5, further comprising a sensor having the transmission cable, the catheter is characterized in that the distance between the tip of one of the cable holding portions and the tip of the other cable holding portion is smaller than the diameter of the transmission cable.

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