Foley catheter adaptor

A safety adaptor having attachment components and reservoir components for use with balloon anchored catheters such that if the catheter is forcibly removed the reservoir components will act as a safety valve and allow the anchoring balloon to deflate. The safety adaptor acts to minimize damage caused to a patient due to the removal of an inflated anchor balloon of a catheter. The safety adaptor attaches to any existing catheter having a fluid balloon and does not require re-engineering or re-tooling of the catheter or adaptor.

II. FIELD OF THE INVENTION

The present invention relates to safety adaptors for use with catheters that have a balloon anchor.

The use of catheters to inject fluid into and drain fluid from a body cavity, vessel, canal, passage or duct of a patient is well-known. For urine drainage, the most commonly used catheter is the Foley catheter, named for its inventor. Certain patients may be catheterized with a Foley catheter to drain urine from the bladder through the urethra. In such a procedure, a catheter is inserted through the urethra until the distal end of the catheter is located in the bladder, after which a balloon adjacent the distal end of the catheter is inflated through an inflation lumen to retain the catheter in the patient. The proximal end of the catheter extends outside the patient's body and is usually connected to a drainage tube leading to a drainage bag. Urine passes through an opening or drainage eye adjacent the distal end of the catheter, through the drainage lumen extending through the catheter, and into the drainage tube to the bag for collection therein.

Foley catheters are generally sterile rubber or silicone tubing and are designed for insertion into the urethral meatus of the penis or vagina for the purpose of draining the urinary bladder. The Foley catheter is inserted until the catheter tip reaches the bladder and urine return is achieved. Once urine is draining through the tubing, sterile water, gas, or other fluid is pushed into a side port of another separate but attached tubing (or lumen) to inflate an external balloon proximate the tip of the catheter inside the bladder to anchor the catheter in the bladder. Currently there is no way of deflating the balloon, except by manually connecting a syringe to the port and removing the fluid.

Anchoring the catheter insures that the device stays in place while performing the desired function and it is also helpful in preventing intentional and/or accidental removal of the catheter. While anchoring the catheter is helpful in preventing its removal, removals do still occur. The removal of anchored catheters presents a serious risk of injury to patients.

An enormous number of urinary catheters are used daily in the United States. It is estimated that approximately 10 to 15 percent of patients admitted to the hospital receive a Foley catheter. Currently, if the balloon affixed to the Foley catheter is manually extracted while inflated, the balloon often tears the urethral mucosa causing strictures (scarring), bleeding, and infections. There have been numerous occasions when patients have self-extracted their catheters with the balloon fully inflated. Significant damage occurs to the urinary tract when such events occur.

A need exists for a safety device that attaches to a catheter that allows for the rapid release of pressure in the anchoring or attachment structures in order to minimize the risk of injury to patients when the catheters are forcibly removed.

IV. SUMMARY OF THE INVENTION

In an exemplary embodiment, the present invention provides an adaptor for use with a balloon anchored catheter, including a tube, a reservoir connected to the tube, an expandable reservoir member connected to the reservoir, and an attachment structure connected to the tube.

In another exemplary embodiment, the present invention provides a catheter system including a main catheter including a main flow tube; an anchoring catheter connected to the main catheter, the anchoring catheter comprising a port, an anchoring flow tube and an anchoring structure; and, an adaptor connected to the anchoring catheter, the adaptor comprising a tube structure; a reservoir connected to the tube structure; an expandable reservoir member connected to the reservoir; and, an attachment structure connected to the tube structure.

In still another exemplary embodiment, the present invention provides a catheter system including a main catheter including a main flow tube; an anchoring catheter connected to the main catheter, the anchoring catheter comprising a port, an anchoring flow tube, and an anchoring structure; and, an adaptor connected to the anchoring catheter, wherein the adaptor acts to minimize damage to a patient due to the removal of the main catheter or the anchoring catheter.

In yet another exemplary embodiment, the present invention provides an adaptor for use with a balloon anchored catheter, the adaptor including means for providing a balloon anchored catheter; and, means for providing a safety valve that allows release of pressure at an anchor balloon site of the catheter when the catheter is removed.

An attachment structure attaches the safety adaptor to a balloon anchored catheter and the adaptor acts to minimize damage to a patient due to the forcible removal of the balloon anchored catheter. The adaptor minimizes damage by rapidly allowing fluid from an anchor balloon of the balloon anchored catheter to enter the reservoir thereby relieving pressure at the anchor balloon site. This rapid release of pressure from the anchor balloon occurs when the force applied to the anchor balloon overcomes the surface tension of a flexible membrane in the adaptor.

The safety adaptor in at least one exemplary embodiment is a medical device that is attached securely to the input/output port of the anchoring balloon of a catheter. The adaptor is a safety device that allows the anchoring balloon to rapidly release itself once a certain amount of force is exerted on the balloon. The adaptor greatly reduces the trauma associated with balloon anchored catheter self extractions.

Given the following enabling description of the drawings, the apparatus and methods should become evident to a person of ordinary skill in the art.

VI. DETAILED DESCRIPTION OF THE INVENTION

The present invention describes an apparatus and method providing a safety adaptor for use with a catheter. The safety adaptor of the present invention allows a catheter to be forcibly removed without causing great trauma to the body. The adaptor acts to rapidly release pressure from an anchor balloon of a balloon anchored catheter when the force applied to the anchor balloon overcomes the surface tension of a flexible membrane of the adaptor.

With reference to the drawings,FIGS. 1A and 1Bshow a balloon anchored catheter10such as a Foley catheter that is insertable into a body cavity, vessel, canal, passage or duct to inject or drain fluid into or from the body. One exemplary use of the catheter10is to drain urine from a patient's bladder and/or to inject fluid into the patient's bladder.

In order to facilitate insertion into the body, the catheter10includes a long, slender, and flexible sterile flow tube20having a distal end24and a proximal end22. The distal end24has a thin tip26that includes an opening28. The flow tube20has attached to it a separate anchor tube30that extends along the length of the flow tube20from the distal end24to the proximate end22. The anchor tube30ends in a fluid intake/output port32at the proximal end. The anchor tube30is also fluidly connected to an anchor balloon36that surrounds the distal end24of the catheter tip26.

The catheter tip26and anchor balloon36are inserted into the bladder while the anchor balloon36is deflated. Once the catheter tip26and anchor balloon36are inside the bladder a fluid is injected through the anchor tube30into the anchor balloon36. This fluid inflates the anchor balloon36such that the diameter of the anchor balloon36exceeds the diameter of the urethra thereby securing the distal end24of the flow tube20including the catheter tip26inside the bladder.

The inflation of the anchor balloon36is achieved by attaching a fluid source (not shown) to the fluid intake/output port32of the anchor tube30. The fluid source may be, for example, a syringe that attaches to a one-way valve34found in the fluid intake/output port32. When the syringe is attached to the intake/output port32, the one-way valve34is depressed and opened allowing fluid to pass into the anchor tube30. A sufficient amount of fluid is then injected into the anchor tube30to inflate the anchor balloon36.

Once the anchor balloon36is sufficiently inflated, the fluid source is disengaged from the input/output port32thereby closing the valve34. Once the valve34is closed, there exists a closed fluid system from the anchor balloon36through the anchor tube30and to the valve34of the fluid intake/output port32. This closed fluid system presents a potential risk of injury to the patient's bladder and/or urethra resulting from the removal of the catheter10and inflated anchor balloon36.

The removal of the catheter10while the anchor balloon is inflated can be intentional or accidental. Generally, the only means for removing fluid from the anchor balloon36is by withdrawing the fluid, for example, with a syringe attached to the input/output port32. However, patient's often attempt to remove the catheter10themselves while the anchor balloon36is inflated. While at other times, accidental mishaps, such as the tubing20,30becoming entangled or snagged can lead to the catheter10being traumatically removed. Both of these occurrences present a substantial risk of injury. These injuries include bleeding, scarring, strictures, rupture of the urethra, rupture of the balloon and contamination due to balloon fragments, etc.

In order to minimize the risk of injury, the present invention in one exemplary embodiment, as illustrated inFIG. 2A, provides a catheter adaptor40that acts to release the fluid pressure in the closed fluid system by allowing the inflated anchor balloon36to be removed without causing serious injury to the bladder or urethra. In one exemplary embodiment, the catheter adaptor40includes an adaptor attachment structure42that attaches the adaptor40to the fluid intake/output port32of the anchor tube30, as illustrated inFIG. 4. The adaptor attachment structure42allows the adaptor40to be attached to most any currently existing catheter without the need for re-engineering or retooling of the catheter or adaptor40.

In keeping with the spirit of the present invention, the adaptor attachment structure42may assume various embodiments for attachment to the outside of the valve housing, including, for example, clothespin, locking arms, clamps, or clasps type fasteners, similar to the fastener illustrated inFIG. 2A. The attachment structure42illustrated inFIG. 2Aincludes a pair of pinch members that hook around a ridge (or other protrusion) commonly found on the fluid intake/output port of a catheter balloon lumen. This structure also allows for a pinching force to be applied if no ridge is present. The pinch members flex to open sufficiently to hook the ridge and/or to clamp the fluid intake/output port. The attachment structure may also assume embodiments including, for example, a Luer lock having threads60, as illustrated inFIG. 2B, or frictional fasteners such as an O-ring62, as shown illustrated inFIG. 2C. The various attachment structures are examples of means for connecting to a balloon anchor valve.

The adaptor attachment structure42is connected to a fluid reservoir48that has an open end. The open end of the fluid reservoir48is configured to engage the fluid intake/output port32of the catheter10. As illustrated inFIGS. 2A and 3A, the fluid reservoir48includes a cylindrical member (or sleeve)44at the open end with the top region flaring out from the cylindrical member44. As illustrated inFIG. 3D, the fluid reservoir48may be just a cylindrical member. A variety of shapes can be utilized for the fluid reservoir48while allowing it to open the fluid intake/output port32and establish fluid communication. The fluid reservoir48includes a tension membrane (or elastic member)50on the end opposite the cylindrical member44. The tension membrane50as illustrated includes an expandable nipple52, which can take a variety of shapes while providing sufficient expansion area for receiving fluid. The tension membrane50and the fluid reservoir48together are an exemplary means for receiving fluid released from an anchor balloon of a balloon anchored catheter during force removal.

The expandable nipple52expands, as illustrated inFIGS. 3C and 3Dto accommodate fluid that enters the reservoir48from the anchor balloon36and anchor tube30when sufficient pressure is exerted onto the anchor balloon36, for instance during the forcible removal of the catheter10while the anchor balloon36is inflated. The tension membrane50and/or expandable nipple52may be, for example, a thin elastic membrane of rubber, polymer or latex that expands or bursts in order to relieve pressure from the anchor balloon36.

In one embodiment, the tension membrane50has a surface tension selected to be higher than the surface tension of the anchor balloon36. This surface tension of the tension membrane50acts under normal system pressures to prevent fluid from entering and expanding the cavity formed by the tension membrane50and the fluid reservoir48such that the anchor balloon36remains inflated. The surface tension of the expandable nipple52is selected to be lower than the surface tension of the tension membrane50. The selected surface tension allows the expandable nipple52to stretch in order to accept at least the amount of fluid displaced from the anchor balloon36and anchor tube30when forces act on the anchor balloon36such as when the catheter10and anchor balloon36are forcibly removed.

In another exemplary embodiment, the expandable nipple52may alternatively be selected to have properties such that the nipple52bursts when a certain amount of fluid is displaced from the anchor balloon36and anchor tube30into the reservoir48when the catheter10and anchor balloon36are forcibly removed. The tension membrane50and/or the expandable nipple52may be designed to suit a variety of conditions. For example, the tension membrane50and/or the expandable nipple52may be designed to exhibit a weakened surface tension that allows the tension membrane50and/or the expandable nipple52to expand very easily. The tension membrane50and/or the nipple52may also be designed to have partial perforations or faults54, as illustrated inFIG. 3B. The faults54facilitate bursting and release of the anchoring fluid under a certain amount of pressure.

When the adaptor40is attached to the catheter10, as illustrated inFIG. 4 and 5, the fluid reservoir48depresses and opens the valve34of the fluid intake/output port32. The fluid reservoir48comprises a male fitting that locks in a female portion of the fluid intake/output port32that when in place fully depresses the valve34of the intake/output port32. The fluid reservoir48including allows a small amount of fluid from the closed fluid system to enter into the tube44of the adaptor40.

Fluid in the anchor balloon36will not be able to escape due to the tension membrane50with expandable nipple52. However, when sufficient pressure is placed on the anchor balloon36inside the urinary bladder (such as when the patient pulls forcefully on the catheter trying to self extract the catheter10) the pressure placed on the anchor balloon36will overcome the tension membrane50of the adaptor40and the fluid will displace from the anchor balloon36so that the catheter10slides out with significantly less trauma to the bladder and urethra.

In practice, when the inflated anchor balloon36is attempted to be pulled into the urethra from the bladder, the urethral wall exerts a certain amount of tension on the anchor balloon36. This tension causes circumferential pressure on the anchor balloon36so that the fluid pressure overcomes the surface tension of the rubber tension member50in the adaptor40. This causes fluid to be displaced to the tension membrane50and expandable nipple52such that the catheter10easily slides out of the bladder.

The foregoing has outlined a safety adaptor for a balloon anchored catheter that acts to minimize damage to a patient due to the forcible removal of the balloon anchored catheter. The adaptor minimizes damage by rapidly allowing fluid from an anchor balloon of the balloon anchored catheter to enter a reservoir and thereby relieve pressure at the anchor balloon site.

The adaptor of the present invention is a medical device that attaches securely to an input/output port of the bladder anchoring balloon of a catheter. The adaptor, in at least one exemplary embodiment, includes an attachment structure that allows the adaptor to be used with most any currently existing catheter, particularly Foley catheters, and greatly reduces the trauma associated with catheter self extractions.

Although the present invention has been described in terms of particular embodiments, it is not limited to those embodiments. Alternative embodiments, examples, and modifications which would still be encompassed by the invention may be made by those skilled in the art, particularly in light of the foregoing teachings.

Those skilled in the art will appreciate that various adaptations and modifications of the embodiments described above can be configured without departing from the scope and spirit of the invention. Therefore, it is to be understood that, within the scope of the appended claims, the invention may be practiced other than as specifically described herein.