Patent Application
20210275400
The present invention relates to improvements in status monitoring of in-dwelling retention balloons for Replacement Gastrostomy Tube feeding devices, placement of such tubes, and improved structural rigidity of such tubes. More particularly, the present invention relates to the overall construction and configuration of gastrostomy tubes and/or enteral feeding catheters having a portion which is deployed outside a living body, and a tube which is inserted through a stoma to a point inside the body for ongoing delivery of nutrition and medications.
Numerous inventions exist in the prior art which create the function of a gastrostomy tube for the purpose of delivering nutritional substances or other compounds directly to a patient's digestive tract within a living body. A subset of these devices are considered replacement gastrostomy tubes and they specifically perform the function of delivering nutritional substances through a surgically created opening to a point typically inside a patient's digestive tract, most commonly inside a patient's stomach. It is particularly important for medical practitioners inserting these devices to confirm placement inside the stomach and to facilitate rapid, accurate placement when replacement is required, and to maximize the lifespan of such tubes thereby minimizing the need for such tubes to be replaced.
Initially, Gastrostomy tubes are surgically placed (Percutaneous Endoscopically placed Gastrostomy Tubes—PEG). These eventually require replacement with a replacement gastrostomy tube. Replacement gastrostomy tubes wear out quickly and several replacements may be necessary per year due to, for example, deformation of a tube and build-up of pathogens on a tube. Additionally, such tubes are anchored within a patient's stomach by a balloon-like structure which may slowly spontaneously deflate. This may cause a tube to fall out and a visit to an emergency room may be required in order to replace a tube. Mechanisms and methods to detect deflation occurring before a tube may become dislodged are not provided by most currently manufactured tube designs, and advances in the related ability offer the potential for improvement in patient care. Mechanisms and methods to improve communication and detection of inflation status of an internal balloon are disclosed in the present invention as well as improvements to facilitate and confirm correct placement of said tubes. Additionally, a method to increase the structural integrity of such tubes is disclosed.
Existing devices have several shortcomings that create negative consequences for patients and caregivers. Existing Replacement Gastrostomy Tubes as customarily designed have a “balloon-like” structure internal to the patient's body after the tube is placed in positon for its function. The balloon structure is inflated with a fluid and is a primary mechanism of retaining a tube at a necessary in-dwelling position. A common failure for such tubes is loss of fluid from the retention balloon over time which creates a risk that a tube will become dislodged when the retaining action of the balloon is lost due to loss of fluid and consequent loss of shape in the in-dwelling balloon structure. Replacement fluid can be added via an external filling port to restore the retention ability of the in-dwelling balloon, however a need for additional fluid for an internal retention balloon is not easily or readily apparent in many prior art designs, or is not of a relatively simple, inexpensive and reliable design. The present invention seeks to resolve these deficiencies by disclosing methods and mechanisms for detecting and communicating the inflation status of such internal retention balloons in simple, reliable and broadly detectable manners.
Existing devices and other information disclosed in prior art lack several key advances included in the present invention. Extensive prior art addresses the broad construction of gastrostomy tubes. A disclosure which relates to similar topics as the present invention is included in patent U.S. Pat. No. 8,177,742 B1 which discloses a method and mechanism for monitoring the inflation status of the internal retention balloon by means of a visual mechanical indicator triggered by a pre-biased inflation pressure sensing mechanism, among other disclosures. The mechanism disclosed however, as will be described, has significant operational and manufacturing complexity in comparison to the present invention, and does not disclose means of communicating the inflation status beyond basic visual means.
U.S. Pat. No. 6,732,734 discloses an external “pilot” balloon that also provides a form of visual and tactile status indication, however the method of connection to the in-dwelling retention balloon requires an air tube, and the reliance on a visual signal which may not occur until significant loss of inflation pressure in the in-dwelling retention balloon. The loss of pressure in in-dwelling retention balloons remain a significant problem for practitioners using this device. These short-comings create the need for a signal mechanism which offers simpler implementation, manufacturing simplicity and a broader means of status communication for inflation status of the in-dwelling retention balloons.
Additionally, moving beyond retention balloon inflation status, placing replacement gastrostomy tubes in their in-dwelling, ongoing operational position requires a medical specialist to insert a replacement gastrostomy tube through an opening in a portion of a digestive tract. Such an opening is not visible to a practitioner and such situations can create difficulty, risk and unproductive time spent aligning a tube with such an opening. Additionally, the body opening through which a tube passes begins to close rapidly after a tube is withdrawn, further increasing the risk and difficulty in positioning a replacement tube. Prior art attempts to partially address these shortcomings by disclosing forms and degrees of taper in the distal tip of a replacement gastrostomy tube such that the tip is smaller than the circumference found in a predominant length of such a tube. The diameter of existing replacement gastrostomy tubes is often, gradually reduced as the tube approaches its distal opening which forms a “tapered” shape which creates a degree of “self-centering” action as such a tube is inserted into a surgically created opening., The degree of taper in such tubes is meaningfully limited however, because a distal opening must remain with a sufficiently large area and shape such as to allow passage of a sufficient quantity and type of nutrient and medication necessary to support the purpose of such gastrostomy tubes. To address the preceding deficiency, a portion of the present invention discloses design and construction principles for a form of temporary distal tip which is designed to remain in place during insertion of a tube and then be removed via some combination of one or more actions including dissolution of the temporary tip by fluids commonly found in a digestive tract, deposition of the tip in a digestive tract by mechanical means of ejection or by the force of initial substances delivered through such a tube, and/or mechanical removal of the tip via withdrawal though the predominant length of a tube in a direction opposite a distal opening of a tube. The design principles for the temporary distal tip of the present invention create an ability for much greater taper than available in prior art, and create a distal tip with the potential for the smallest possible distal surface area, thus creating much-improved self-centering functionality to support placement of a tube in comparison to prior art while retaining the area of distal opening necessary for function of the tube in delivering nutrients and medications.
In some cases, it is possible to insert the replacement tube through the prior tract which had led to the stomach but instead, with insertion of the new tube, the new tube creates a break in the stoma allowing the tube to enter the peritoneal cavity such that a distal opening of a replacement gastrostomy tube assumes an in-dwelling location such that said distal opening will discharge feeding materials into an unintended location. Such a situation creates extreme danger and must be rapidly corrected, however technical means of confirming with high confidence that a tube distally terminates in a stomach is often not available to medical practitioners charged with inserting such tubes. Fluids uniquely present within a stomach are, in many cases, uniquely acidic within a digestive tract, and as such, confirmation that the distal tip of said replacement gastrostomy tubes is in contact with a highly acidic fluid provides a meaningful additional confirmation that a recently-placed tube's distal opening is in fact within a stomach. The present invention discloses a feature which, when incorporated into gastrostomy tubes of customary design allows methods to be employed to assess acidity of fluids drawn into a distal end of a gastrostomy tube, facilitating said assessment of a tube's in-dwelling placement location. For example, when sufficient fluid which has accumulated in the stomach and is then suctioned up into the tube via a syringe attached to the proximal port, contact between this fluid and a ph sensitive substance embedded within the tube of the present invention can indicate whether the acidity of the fluid is such as to confirm that the tube is in fact placed in a stomach and not misplaced in another cavity. In practice, this procedure of assessing whether such a tube is placed in a stomach via analysis of liquid drawn into such a tube will usually require that a fluid such as sterile water be injected through the tube in order to provide sufficient fluid in a stomach to withdraw and assess for ph level.
A further weakness of existing replacement gastrostomy tubes is a common tendency for the tubes to deform over time after being placed in a body, and the deformation can make the tubes collapse or deform to a shape that prevents delivery of nutrients and make the tubes no longer fit for purpose, thus mandating their replacement. This deformation is due to deficiencies in materials commonly used for the tubes in dimensions necessary to balance nutrient delivery and minimally invasive stoma dimensions. The present invention discloses a structural approach to improving the structural integrity, and hence longevity, of a tube while retaining tube dimensions similar to current replacement gastrostomy tubes.
The present invention discloses methods and mechanisms to communicate inflation status of the in-dwelling balloon by additional means beyond a visual status gauge as disclosed in prior art. These means include wired or wireless communication to a remote location, triggering of a status communication device using a form of pressure-sensing mechanism in fluid contact with an in-dwelling retention balloon, and additional forms of visual and tactile status alerts such as a blinking light or auditory signal. Additionally, the present invention discloses a method of generating an alarm based on a particular status being detected, the alarm being communicated in any form whereby an external signal is generated based on a particular inflation status being detected, typically indicating reduced inflation and associated risk of undesired movement in the overall replacement gastrostomy tube device and associated risk of a tube falling out of a stomach.
To address the issues associated with previously disclosed methods as described herein, the present invention discloses a method of communicating the status of an in-dwelling retention balloon customarily found as part of a replacement gastrostomy tube. The method integrates output from any form of pressure-sensing device in fluid communication with an in-dwelling retention balloon, and communicates detected pressure information as a means of indicating the inflation status of the in-dwelling retention balloon. The pressure information may trigger local or remote alarms, using auditory, visual or remote network facilitated indicators of detection of a particular pressure (and corresponding inflation status) of an in-dwelling retention balloon. The communication may indicate a range of pressures and statuses, or trigger a communication based on detection of an adjustable, user-entered pressure to create an alarm function. The communication may also be remote via, wired, wireless, network-connected, or other means of remote communication. A power storage battery source may be included with the mechanism to power an alarm. Example alarms may include a light signal, such as a blinking light, an auditory signal such as an intermittent sound, and/or a remotely communicated alarm via wired or wireless network communications (or a combination thereof) to alert medical staff of low pressure in an internal retention balloon.
Additionally, the present invention discloses principles for designs and construction materials to create a temporary distal tip with a purpose of facilitating accurate and easy placement for replacement gastrostomy tubes with the tip having much greater self-centering taper than disclosed in prior art. As discussed herein, a key design challenge for existing replacement gastrostomy tubes is how to make the tube as easy to place in an opening within the digestive tract as possible. Existing designs attempt to address this need by incorporating varying degrees of taper between the permanent integrated distal opening and the remainder of the tube, however the degree of taper available in the prior art is limited by the need to retain a distal opening sufficiently large for nutrients to pass through with sufficient speed and quantity. Those familiar with the field and art will recognize that, for tubes meant for adults, this opening is customarily less than a diameter of 20 French for adult-use tubes which is created by a taper from the diameter from the remainder of such tubes. Tubes for pediatric use are typically smaller diameters. The present invention provides design and construction principles to create a temporary distal tip to be used during the placement into a stomach for replacement gastrostomy tubes of any dimensions and is not restricted to the diameter described above which are provided for background and context. The tip of the present invention, due to its temporary nature, is not constrained by the need for a size of distal opening to allow food to exit such tubes. The present invention accomplishes this by disclosing tip design principles for a temporary distal tip which includes taper to, for example, the point where minimal distal surface is retained, or any size of distal tip surface and shape which terminates in a diameter smaller than the opening size for the distal end of a replacement gastrostomy tube. This is accomplished by constructing the tip using materials which may dissolve and/or be removed from the device once it is placed in its in-dwelling position and which materials may enter a digestive tract or be withdrawn from such tubes. The tip device of the present invention may be dislodged from a tube by mechanical or chemical means once in place, or be forced out by food flow through such tubes, but in any case, the temporary tip of the present invention is removed for a tube to reveal an ongoing tip of necessary size and shape after a tube has been placed in position for ongoing use.
Additionally, to address the shortcomings in the previously known art related to deformation of a replacement gastrostomy tube due to weakening of the material of its construction over time, the present invention discloses a design and construction feature which reduces the potential for replacement tubes of customary design to deform with age. This feature consists of a reinforcement layer of materials suitable to achieve greater shape retention than customary unreinforced tubes using a uniform material, The present invention discloses incorporation of a latticework mesh structure incorporated into the construction material of replacement gastrostomy tubes and extending over some or all of the length of such tubes with intent to preserve a generally tubular shape, sufficient to allow such tubes to continue to perform their intended function, on both the internal lumen of such tubes and external circumference of such tubes. The reinforced portions of a main feeding tube and/or ancillary ports may extend over all, or a subset, of such tubes and ports.
Additionally, to address the shortcomings in prior art related to the potential for a replacement gastrostomy tube to be misplaced such that the distal opening of a tube is placed in a location other than a stomach, the present invention discloses a feature which, in combination with methods known to medical practitioners skilled in the related art, creates an enhanced means of confirming and documenting that distal openings of such tubes are located within a stomach. This feature embeds a ph-sensitive material in a location on the internal lumen of such tubes with the material being visible through the translucent nature of the tubes, and located within the portion of the tubes that will be external to the body-surface stoma and visible to a medical practitioner when the tubes are placed in their in-dwelling position. This ph-sensitive material will provide, when fluid at the distal opening of an in-dwelling tube is withdrawn and placed in contact with the previously described ph-sensitive material, both an indication, based on the ph-of the fluid as indicated by visual signs from the ph-sensitive material, of whether stomach placement of a distal opening can be confirmed.
The included drawings depict the present invention integrated with a replacement Gastrostomy tube of customary design, as well as the distinct components of the present invention.
Reference will now be made in detail to one or more embodiments, examples of which are illustrated in the drawings. It should be understood that features illustrated or described as part of one embodiment may be used with another embodiment to yield still a further embodiment. The present invention comprises an assembly for use in Replacement Gastrostomy Tubes, comprising one or more of: a status device able to trigger an alarm that indicates the inflation status of a retention balloon; 2) a temporary distal “tip” structure for use in centering the replacement gastrostomy tubes in vivo; 3) a gastrostomy tube design comprising an inner mesh latticework structure to increase the structural integrity of such tubes; and 4) a gastrostomy tube design enhancement comprising a pH sensor for measuring acidity of fluid at a distal tube opening.
An exemplary embodiment of the status device 13 is illustrated in
Various exemplary embodiments of the temporary distal tip are illustrated in
In one or more embodiments, the present invention comprises a kit with written instructions, or a posted link to online instructions on use of the kit, and wherein the kit comprises one of more of the devices of
Specifically focusing on
The disclosed apparatus may be configured to send or display communication signals indicating the pressure status in a stand-alone manner and/or to other devices, such alarms including but not limited to audible alarms with optionally configurable volume, network connected data and alarms, or other forms of wired or wireless data transport where the data indicates the status of the pressure detected from fluid connection to the internal retention balloon. The placement and design as depicted are shown as examples and the present invention extends to any form of incorporation of a pressure-sensing device in fluid communication with the in-dwelling retention balloon, and which includes a device to display, emit or convey a signal which may be interpreted as an indication of low pressure and consequently degraded inflation status of an internal retention balloon. A battery power source or other source of stored power may also be included to power the generation of the signal. This power source may be replaceable or permanently embedded within the device.
Addressing the specifics of
The present invention includes a sensing unit module 4 comprising hardware device receiving input from any form of pressure sensing apparatus that detects when a pressure threshold is reached for the retention-balloon fluid that is in communication with an in-dwelling retention balloon. The device may produce, upon triggering of a low-pressure threshold, any combination of an auditory alarm via an alarm module 3 such as a “beeping” tone, a visual signal such as some form of light, or a data signal such as would be connected to a network, or wirelessly communicated to a separate signaling apparatus. Additionally, the invention may optionally allow a user to specify the type of alarm or alarms that are issued when a low-pressure situation is detected by the device.
Assessment of pressure in the communication fluid may be performed by any means disclosed in prior art as depicted by the sensing module 4 (e.g. a pressure sensor of prior art) and transmitted to the presently disclosed invention via an interface point 5. A location for a form of power storage 6 is depicted which powers circuitry 7 which serves to interpret data from the pressure sensing mechanism 4 and to trigger and control the alarm function module 3. The circuitry is in physical or wireless connection 8 with the sensor interface 5 and the alarm mechanism 3. The physical implementation including, for example the placement and sequence of the modules described may vary in any manner provided the overall functions of the device are achieved as specified herein. Additionally, the invention may optionally allow a user to specify the pressure at which an alarm is triggered. Examples of such adjustment mechanisms may include digital entry of a precise pressure below which would trigger an alarm or a simple relative pressure selection such a high/medium/low, however any form of pressure specification is within the scope of the present invention.
The depiction of
Turning to
The assembly/kit of the present invention further comprises a separable tip. Turning to
A degree of taper which exceeds that found in previously disclosed designs is depicted by gradually converging boundary lines 17 which depict an example of the taper from the wider extent at the proximal end of the tip 18 to a narrower distal end point 15 supported by the present separable tip, however the depicted angle of taper is an example and any angle or and shape that creates a converging form between the proximal and distal portions of the separable tip is covered by the present invention. The separable tip may be constructed of materials dissolvable in digestive fluid (e.g. gelatin) and/or of a size and shape such as to be excreted from a body upon separation from the replacement gastrostomy tube once placed in an in-dwelling position. In this embodiment, the actual concluding distal tip is depicted as a rounded, closed tip 15, however any terminating shape for the distal tip that is of smaller area that those provided by previously disclosed designs is within the scope of the present invention. The concluding shapes forming the tip may include any form of tapered shape or shape with a smaller distal end-point than previously disclosed gastrostomy tube distal openings, and open or closed tip designs, each including a distal end point consisting of an opening smaller than the smallest of previously disclosed gastrostomy tube distal openings. A portion of the overall tip structure 18 will be embedded within or around a replacement gastrostomy tube to secure it during the placement procedure. A surface as depicted 18 will secure, via means such as compressive friction or weak adhesive, the present invention of
Materials which satisfy the requirement of having sufficient rigidity to serve the self-centering placement function and to safely enter the digestive tract are readily apparent to those familiar with the field of practice. A commonplace example found in most domestic settings is the use of a gelatin container of a size and shape sufficient to swallow (commonly referred to as “gel caps”) which contain a substance to be delivered to the digestive tract. In one example, an outer gelatin shell is dissolved in digestive fluids and contents of the “gel-cap” are deposited in a digestive tract. A similar principle would apply in the case where the presently disclosed distal tip is constructed of a material with identical or similar characteristics to gelatin or any other material which can safely be deposited into the digestive tract where it may either partially or fully dissolve, or be excreted partially or fully intact.
Devices are also well-known in the field of the art which are designed to pass completely through the digestive tract (for example, diagnostic cameras), and similar principles may be applied to removal of a dislodged temporary tip of the present invention from a gastrostomy tube once positioned in place for a tube's ongoing function.
