Balloon catheter

Abstract

To provide a balloon catheter whose sensor hardly projects to the outside.SOLUTION: A balloon catheter 100 comprises: a tube 12 having openings 16 and 17 formed therein to communicate with a lumen 15; a balloon 13 provided around the outer periphery of the tube 12; and a sensor body 31 which is provided at the tip of a transmission cable 32 and is freely movable together with the transmission cable 32 within the lumen 15. The sensor body 31 is positioned inside the balloon 13.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a balloon catheter.

Background Art

[0002] Acute kidney injury (AKI), which occurs in 30 to 50% of inpatients in the intensive care unit, 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. In order to measure the oxygen partial pressure in this urine in the bladder, a urethral catheter has been proposed that projects an oxygen partial pressure measuring sensor from the side hole of the urethral catheter to measure the oxygen partial pressure in the bladder or the bladder wall (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the urethral catheter according to the above conventional technology, since the oxygen partial pressure measuring sensor is projected laterally from the tip of the catheter body, there is a risk that the oxygen partial pressure sensor may hit the urethra when the urethral catheter is inserted, or that the oxygen partial pressure may not be measured appropriately.

[0005] Further, even if the tip portion of the oxygen partial pressure measurement sensor is arranged or fixed in front of the balloon and near the side holes, during the process of inserting the catheter body into the urethra, especially in the case of men, when passing over the pendulum portion that moves left and right, up and down, the curved spherical portion, and the constricted muscular sphincter, the tip portion of the catheter was likely to kink due to being soft and having low strength. In addition, due to the formation of the side holes, if there is a metal sensor such as stainless steel near the side holes, there is a risk that the metal sensor will pop out from the side holes and hit the urethra when kinking occurs.

[0006] An object of the present invention is to solve the problems caused by the above-mentioned conventional technologies and provide a balloon catheter in which the sensor is difficult to pop out to the outside.

Means for Solving the Problems

[0007] The present invention provides a balloon catheter including a tube having an opening communicating with the inner cavity, a balloon provided on the outer periphery of the tube, and a sensor body provided at the tip of a transmission cable and movable within the inner cavity together with the transmission cable, wherein the sensor body is located inside the balloon.

[0008] In this case, the transmission cable may be fixed to the tube via a fixing portion attached to the proximal end side of the tube. The length from the fixing portion to the tip of the sensor body may be the same as or shorter than the length from the fixing portion to the tip side expansion end of the balloon. The length from the fixing portion to the tip of the sensor body may be the same as or longer than the length from the fixing portion to the base end side expansion end of the balloon.

Effects of the Invention

[0009] The present invention can provide a balloon catheter in which the sensor is difficult to pop out to the outside.

Brief Description of the Drawings

[0010]

Figure 1

Figure 2

Figure 3

Figure 4

Mode for Carrying Out the Invention

[0011] Hereinafter, a balloon catheter according to an embodiment of the present invention will be described with reference to the drawings. Fig. 1 shows a side view of the balloon catheter, Fig. 2(a) shows a cross-sectional view of the tip of the balloon catheter with the balloon contracted, Fig. 2(b) shows a longitudinal sectional view of the tube, Fig. 3 shows a cross-sectional view of the tip of the balloon catheter with the balloon inflated, and Fig. 4 shows a cross-sectional view of the proximal end of the balloon catheter.

[0012] As shown in Fig. 1, the balloon catheter 100 includes a catheter body 10, a sensor 30, and a fixing portion 40. This balloon catheter 100 is a product in which 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 and integrated.

[0013] The catheter body 10 is composed of a distal end portion 11, a tube 12, a balloon 13, and a branch portion 14. On the distal end side of the catheter body 10, the distal end portion 11 and the balloon 13 are coupled to the tube 12, while on the proximal end side of the catheter body 10, the branch portion 14 is coupled to the tube 12 and integrally formed.

[0014] The tip 11, tube 12, balloon 13, and branch portion 14 according to this embodiment are formed of silicone rubber, but may be formed of latex, natural rubber, isoprene rubber, thermoplastic resin, for example, PVC and urethane rubber, fluororubber, fluororesin, or the like.

[0015] As shown in Fig. 2(a), the tube 12 passes through the balloon 13, and the balloon 13 is provided on the outer periphery near the tip by adhesion. Further, the tube 12 has a tip portion 11 formed in a cylindrical shape on the end face of the tip attached by adhesion. The tube 12 has a urine discharge lumen (inner cavity) 15 for flowing urine formed along the extending direction of the tube 12. The urine discharge lumen 15 communicates with the outside through a tip hole (opening) 16 and a side hole (opening) 17 formed in the tip portion 11, and the urine flowing in from the tip hole 16 and the side hole 17 flows through the urine discharge lumen 15 to the branch portion 14 on the proximal end side.

[0016] A part of the tube 12 is formed thick, and a balloon lumen 18 for inflating the balloon 13 is formed along the extending direction of the tube 12 in the thick portion. The balloon lumen 18 is fluidly communicated with the inside of the balloon 13 near the tip, 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.

[0017] As shown in Fig. 2(b), the urine discharge lumen 15 is formed to have a substantially circular flow path cross section, and the balloon lumen 18 is formed to have a circular flow path cross section smaller than that of the urine discharge lumen 15.

[0018] As shown in Fig. 2(a), the balloon 13 is formed to be cylindrical when not inflated. The non-inflated portions on the tip side and the base end side of the balloon 13 are formed in a tapered shape, and the outer diameter smoothly decreases toward the tip and the base 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 tip-side inflated end 13A and the base-end side inflated portion 13B, as shown in Fig. 3. Thereby, the balloon catheter 100 is fixed so that the balloon 13 is caught in the patient's bladder and cannot be removed.

[0019] As shown in Fig. 4, one end of the branch portion 14 is connected to the tube 12 on the tip side, while the other end is divided into three openings: a balloon injection port 19, a transmission cable insertion port 20, and a urine discharge port 21.

[0020] 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.

[0021] The transmission cable insertion port 20 extends linearly with respect to the urine discharge lumen 15. The sensor 30 inserted straight into the transmission cable insertion port 20 is directly inserted into the urine discharge lumen as it is.

[0022] The urine discharge port 21 extends obliquely with respect to the urine discharge lumen 15 and can be connected to a urine discharge tube (not shown) or the like, and is connected to a urine bag or the like through the urine discharge tube.

[0023] The sensor 30 inserted into the transmission cable insertion port 20 includes a sensor body 31 and a transmission cable 32, as shown in FIG. 3. The sensor 30 according to this embodiment is an oxygen partial pressure measurement sensor. The sensor 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 body 31 to the phosphor.

[0024] The sensor body 31 is provided at the tip of the transmission cable 32 and is movable together with the transmission cable 32 within the urine drainage lumen 15. That is, the sensor body 31 can be curved independently of the curvature of the tube 12 within the urine drainage lumen 15. In FIGS. 2(a), 2(b), and 3, the sensor body 31 and the transmission cable 32 are in contact with the inner surface of the urine drainage lumen 15, but since the sensor body 31 and the transmission cable 32 are not directly fixed to the tube 12, they can swing freely.

[0025] As shown in FIG. 4, 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.

[0026] The fixing portion 40 includes a fixing portion main body 41, a fixing portion cap 42, and a tightening portion 43. This tightening portion 43 has an annular shape with a through hole 43A formed in the center through which the transmission cable 32 can pass. The fixing portion 40 has the tightening portion 43 sandwiched between the fixing portion main body 41 and the fixing portion cap 42 that is 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.

[0027] As shown in Fig. 3, the length from the end face on the proximal end side of the fixing portion 40 to the tip of the sensor body 31 is shorter than the length from the end face on the proximal end side of the fixing portion 40 to the tip-side inflated end 13A of the balloon 13, and is longer than the length from the end face on the proximal end side of the fixing portion 40 to the base-side inflated end 13B of the balloon 13.

[0028] The sensor body 31 is fixed such that the transmission cable 32 has an appropriate length at the fixing portion 40, so that the sensor body 31 is held inside the balloon 13 without being fixed by adhesion or the like in the urine drainage lumen 15 of the tube 12.

[0029] The balloon catheter 100 according to the present embodiment includes a tube 12 formed with a tip hole 16 and side holes 17 communicating with the urine drainage lumen 15, a balloon 13 provided on the outer periphery of the tube 12, and a sensor body 31 provided at the tip of the transmission cable 32 and movable in the urine drainage lumen 15 together with the transmission cable 32. The sensor body 31 is located inside the balloon 13. Thereby, when the balloon catheter 100 is inserted into the urethra, the sensor body 31 is held inside the balloon 13, so that it is possible to prevent the sensor body 31 from protruding outside from the tip hole 16 or the side holes 17.

[0030] As described above, the present invention has been described based on the embodiments, but the present invention is not limited thereto. For example, in the above embodiment, the length from the end face on the proximal end side of the fixing portion 40 to the tip of the sensor body 31 is such that the sensor body 31 is located between the tip-side inflated end 13A of the balloon 13 and the base-side inflated end 13B of the balloon 13, but it is not limited thereto. As long as the sensor body 31 does not protrude outside from the tip hole 16 or the side holes 17, the length from the end face on the proximal end side of the fixing portion 40 to the tip of the sensor body 31 may be the same as the length from the end face on the proximal end side of the fixing portion 40 to the tip-side inflated end 13A of the balloon 13, or the length from the end face on the proximal end side of the fixing portion 40 to the base-side inflated end 13B of the balloon 13, or may be located inside the non-inflated portion of the balloon 13.

[0031] Also, in the above-described embodiment, the sensor 30 composed of the irradiation unit and the optical fiber is used, but the present invention is not limited thereto. Any sensor capable of measuring the oxygen partial pressure may be used, and sensors based on other methods may also be used.

Explanation of Reference Numerals

[0032] 10…Catheter body 11…Tip portion 12…Tube 13…Balloon 13A…Tip-side expansion end 13B…Base-side expansion end 14…Branching portion 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 30…Sensor 31…Sensor body 32…Transmission cable 40…Fixing portion 41…Fixing portion body 42…Fixing portion cap 43…Tightening portion 43A…Through hole 100…Balloon catheter

Claims

1. In a balloon catheter, a tube having an opening communicating with the inner cavity, a balloon provided on the outer periphery of the tube, and a sensor body provided at the tip of the transmission cable and movable within the inner cavity together with the transmission cable. The balloon catheter is characterized in that the sensor body is located inside the balloon.

2. The balloon catheter according to claim 1, wherein the transmission cable is fixed to the tube via a fixing portion attached to the proximal end side of the tube.

3. The balloon catheter according to claim 2, wherein the length from the fixing portion to the tip of the sensor body is the same as or shorter than the length from the fixing portion to the tip-side expansion end of the balloon.

4. The balloon catheter according to claim 2, wherein the length from the fixing portion to the tip of the sensor body is the same as or longer than the length from the fixing portion to the base-end side expansion end of the balloon.

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