Fecal discharge collection device

The present invention provides devices for collection of stool or fecal discharge. In an embodiment said device comprising a retaining component configured for deployment within a subject's rectum and having an annular cross-section, said annular cross-section of the retaining component forming a fluid inlet into an open end of a collection component affixed to said retaining component and forming a receptacle for matter discharged from a subject's rectum.

FIELD OF THE INVENTION

The invention relates to the domain of stool collection, and provides devices for collection of stool or fecal discharge.

BACKGROUND

As contents move through the gastro-intestinal (GI) tract, they pass through the stomach, small intestines, and colon. Stomach acids break down these contents so nutrients can be easily absorbed by the small intestines before reaching the colon where predominantly water is absorbed and stool becomes formed. The rectum is the most distal region of the colon and serves as temporary storage for intestinal effluents before they are expelled. As rectal pressure increases and the rectal wall expands due to materials filling it from within, a desire to defecate occurs. This desire causes the internal anal sphincter muscle to relax and the external sphincter to contract. As rectal peristalsis continues to push effluents towards the anal canal, continued relaxation of the sphincter muscles allow feces to pass. If defecation is not attended to, stool stays in the rectum where water continues to be absorbed and the stool continues to harden. If stool is left in the rectum for long enough, it can cause pain and result in difficulty to expel or pass the stool mass. This is normally called constipation.

When constipation occurs, there are multiple treatments available to help soften the stool and increase the ease of expulsion. These include the use of oral stool softeners and laxatives, as well as suppositories and enemas. Enemas have been established as a quick and effective management technique to aid in the evacuation of colonic contents by administering irrigation liquids via the anus to the intestines, preferably to both the rectum and colon. This helps soften the hardened stool mass, lubricate the rectal tissue, and stimulate contraction of the rectal muscles, called peristalsis. People who become constipated due to disruption of the nervous system or diseases of the colon and rectum often benefit from these procedures. Those who suffer from slow colonic transit, often resulting from immobility or certain medications (such as opioids), benefit from the use of these treatments as well.

Instillation of fluids into the colon is also a common practice for reasons other than stool evacuation. Patients may receive medicated enemas for treatment of certain diseases such as inflammatory bowel disease or infections such asClostridium difficile. Furthermore, fecal microbiota transplants, which involve the administration of healthy liquefied fecal matter into the colon, are becoming more common treatments for the same conditions.

Due to various factors such as traumas, diseases, age, or recent surgery, there are a number of people who are in need of these types of procedures, but are not able to move to a toilet for evacuation. For these groups of bedridden patients, enemas are normally performed while lying down on the bed and effluents are caught with diapers, pads, or bedpans. This causes stool to be exposed to the patient, care provider, and care environment, which is unhygienic and can increase the risk of infections and other complications. Furthermore, the cleaning of these patients and changing of diapers, clothing, and linens quickly becomes time consuming and an economic burden.

Current standards for containment of fecal output in bedridden patients are quickly shifting to the use of indwelling drainage catheters placed in the rectum. Though these have proven efficacious, they have significant limitations in use cases, are known to cause secondary complications, and have been described as uncomfortable or painful by patients. Their limitations and complications include:Rectum must be clear of any stool before placement.Must be inserted manually using a finger to place the device.Collection of liquid to semi-liquid stool only.Risk of lumen occlusion and/or expulsion if patient has semi-formed to formed stool.Risk of spontaneous expulsion if patient has weak or damaged anal sphincter muscles.High pressures placed on tissues causes painful internal ulcers and necrosis.

There is accordingly a need for a fluid delivery and collection device for fecal discharge that addresses the above shortcomings.

SUMMARY

The present invention provides devices for collection of stool or fecal discharge.

An embodiment of the invention comprises a device for collection of fecal discharge, said device comprising a retaining component configured for deployment within a subject's rectum and having an annular cross-section, said annular cross-section of the retaining component forming a fluid inlet into an open end of a collection component affixed to said retaining component and forming a receptacle for matter discharged from a subject's rectum.

The retaining component may include an annular body comprising a first material and a resilient ring comprising a second material, wherein the annular body overlays the resilient ring and forms an outer periphery of the annular retaining component.

The resilient ring may be configured to exert outward radial pressure of between 5 mmHg and 100 mmHg.

The thickness of the first material of the annular body between the resilient ring and an outer circumferential periphery of the retaining component may lie between 1 mm and 20 mm.

The first material and the second material may have either or both of different flexural modulus and different durometer.

In an embodiment of the invention, a first flexural modulus of the first material may be lower than a second flexural modulus of the second material.

In another embodiment, a first durometer of the first material may be lower than a second durometer of the second material.

The first flexural modulus of the first material may lie between 100 KPa and 100 MPa, and the second flexural modulus of the second material may lie between 20 GPa and 210 GPa.

In an embodiment, the first durometer of the first material is between 0 sh OO-70 sh A based on Shore Durometer testing, and the second durometer of the second material is between 40 HRB-70 HRC based on Rockwell Hardness testing.

The retaining component may comprise a plurality of vertically stacked ring structures. In an embodiment of the device, each of two or more of the plurality of vertically stacked ring structures comprises an annular body comprising the first material and a resilient ring comprising the second material, and wherein the annular body overlays the resilient ring and forms an outer periphery of vertically stacked ring structure. In a further embodiment, the thickness of the first material of the annular body between the resilient ring and an outer circumferential periphery of the vertically stacked ring structure is between 1 mm and 20 mm. In another embodiment, the first material and the second material have either or both of different flexural modulus and different durometer.

DETAILED DESCRIPTION

The invention comprises a device for collection of fecal discharge and which includes a retaining component for retaining a part of the device within the rectum, coupled with a collection component for collecting stool or liquid discharge received from the rectum. The device may additionally include a fluid delivery component to enable delivery of fluid to the colon, and/or a withdrawal component to support safe removal of the device from the patient.

The invention may also include an insertion component to constrain the retaining component in a collapsed state during placement into the rectum,

As described in more detail below, the retaining component may comprise a flexible and resilient substantially “ring-like” structure defining a lumen or passage within the periphery thereof. The retaining component is caused by its resilient properties to naturally expand from a collapsed state having a small cross sectional area to an expanded state having a larger cross sectional area. The resilient properties of the retaining component ensures that in an expanded configuration the retaining component presses against the rectal walls, causing the external peripheral surface(s) of the retaining component to resiliently conform to adjacent rectal walls and to ensure that a complete seal is created between the external periphery of the retaining component and the rectal walls—thereby ensuring that any stool or fecal discharge passes through the lumen of the retaining component instead of leaking through spaces between the external periphery and adjacent rectal walls.

The collection component (or transit sheath) comprises a bag, chute or tube made of a thin, low-friction, flexible, skin friendly material that has an open first end through which stool or fluid may enter said collection component. The first end of the collection component may be coupled with the retaining component such that stool or liquid discharge entering the lumen of the retaining component passes into the collection component through the open proximal end of said collection component. The collection component may be configured to hold and contain material that passes into it through the open proximal end. The other end of the collection component may in an embodiment be a closed end, so as to ensure that the stool or liquid discharge is retained within the collection component.

The insertion component may take any number of different forms. In one, the insertion component is a type of obdurator that is able to be fragmented or disassembled, within which the retaining component is confined in a compressed state. The obdurator may be used to deliver the retaining component into a subject's rectum (in the compressed state), and the retaining component is thereafter released from confinement within the obdurator—thereby permitting it to transition to an expanded state. The obdurator is subsequently withdrawn from the rectum, while the expanded retaining component remains within the subject's rectum. Since the retaining component is coupled to the collection component, stool or fluid discharge from the rectum entering the retaining component transits into the collection component, which is at least partially positioned outside the rectum.

The fluid delivery component comprises an assembly configured to deliver fluid from an external source to the subject's rectum while the retaining component is positioned within the rectum. The fluid delivery component comprises a fluid conduit having an open proximal end, a distal end and a lumen connecting the two—and may in an embodiment comprise a length of tubing or piping of appropriate diameter. The fluid delivery component may be coupled with one or both of the retaining component and the collection component such that when the retaining component is positioned within a subject's rectum, the open proximal end is positioned within the subject's colon while the distal end lies outside of the rectum. The lumen connecting the two ends provides a fluid passageway that enables fluid to be delivered from the distal end through the open proximal end and to the subject's colon. As a result of the configuration, the fluid delivery component enables delivery of enema fluid into the subject's rectum once the retaining component has been positioned within the rectum.

The withdrawal component comprises a structure or assembly that is configured to change either or both of the orientation and/or cross-section of the retaining component to enable withdrawal of the retaining component from the rectum. In an embodiment discussed in this invention the withdrawal component and the fluid delivery component may comprise a single component.

Specific embodiments of the above are discussed in greater detail below.

FIG.1Aillustrates the relevant portions of the human rectum100, including rectal walls102, the anorectal junction104, the anal canal106, and the anal verge108. InFIG.1A, anal canal106is shown in a constricted position.FIG.1Bdepicts the same portions of the rectal anatomy but with the anal canal106now in an expanded position (for example when the subject is passing stool).

FIG.2Aillustrates an embodiment of the retaining component200in an expanded state. Retaining component200comprises a pliant and collapsible annular body202comprising a first material and a resilient ring204comprising a second material, with resilient ring204embedded within said annular body202. Annular body202may additionally include a port (or retaining cavity)206for housing or holding an end of the fluid delivery component.

Owing to the fact that it is comprised of collapsible annular body202and a resilient ring204embedded therewithin, retaining component200can be collapsed into a number of different configurations to reduce its cross-sectional profile for the purposes of delivering it into a subject's rectum.

FIG.2Billustrates a first exemplary configuration into which retaining component200can be collapsed—wherein in said collapsed state, retaining component200has been compressed and collapsed along two mutually perpendicular axes to form two peaks208,208′ and two troughs210,210′.

FIG.2Cillustrates a second exemplary configuration into which retaining component200can be collapsed—wherein in said collapsed state, retaining component200has been compressed and collapsed along three axes, each arranged with 120 degrees between them, to form three peaks208,208′,208″ and three troughs210,210′,210″.

It would be understood that the embodiments ofFIGS.2B and2Care only exemplary and that retaining component200can be collapsed into any number of other compressed configurations. However, it will be noted by comparing the embodiments ofFIGS.2B and2Cto the illustrated embodiment inFIG.2A, that in its collapsed state, the cross-sectional profile of retaining component200is substantially reduced—enabling convenient insertion into and withdrawal from a subject's rectum.

FIG.3illustrates an assembled device300for collection of fecal discharge, said device300comprising retaining component200for retaining a part of the device within the rectum, coupled with a collection component302for collecting stool or liquid discharge received from the rectum, and a fluid delivery component304for delivery of fluid to the colon. In the illustrated embodiment, and as discussed in further detail below, the fluid delivery component304may also act as a withdrawal component to support safe removal of the device300from a patient's rectum.

As illustrated inFIG.3, collection component302comprises a bag (or alternatively a chute or tube) made of a thin, low-friction, flexible, skin friendly material that has an open first end306through which stool or fluid may enter said collection component302. The open first end of collection component302may be coupled with retaining component200such that stool or liquid discharge entering an annular opening308formed by the retaining component200, passes into the collection component302through first open end306of said collection component302. The collection component302may be configured to hold and contain material that passes into it through the open proximal end. In an embodiment, this is achieved by ensuring that a second end310of collection component302is a closed end.

Also shown inFIG.3is fluid delivery component304—which comprises an assembly configured to deliver fluid from an external source to the subject's rectum while the retaining component200is positioned within the rectum. Fluid delivery component304comprises a fluid conduit312having a first open end314positioned proximal to retaining component200and a second open end316positioned distal to retaining component200. As shown inFIG.3, second open end316of fluid delivery component304may include a connector318, which enables fluid delivery component304to be connected to a fluid source. Fluid from the fluid source may enter second open end316, pass through fluid conduit312and be delivered into a subject's rectum through first open end314of fluid conduit312. Referring back toFIG.2A, in an embodiment of the invention, fluid conduit312or first open end314of said fluid conduit312may be housed or held within port (or retaining cavity)206of retaining component200—which ensures that when retaining component200is disposed within a subject's rectum, first open end314of fluid conduit312is also disposed within the subject's rectum, thereby enabling fluid to be delivered to the subject's rectum or colon through fluid delivery component304.

FIG.4illustrate an exemplary instance of device300for collection of fecal discharge positioned within a patient's rectum100. As shown inFIG.4, retaining component200is positioned within the subject's rectum100above the shelf structure formed by the subject's anorectal junction104. Owing to the distance between the walls of the rectum100above the anorectal junction104, retaining component200has transitioned to its expanded state, and in its expanded state rests securely on the walls of the anorectal junction104. Since the distance between the walls of the anal canal106beneath the anorectal junction are narrower than the expanded cross section of retaining component200in its expanded state, retaining component200is securely held by anorectal junction104and accidental withdrawal of retaining component200from the subject's rectum is prevented.

It would be understood that retaining component200may be delivered to a position above the anorectal junction104by compressing retaining component200into a configuration having a cross-section less than the cross-section of anal canal106, delivering said retaining component200(while remaining in a compressed configuration) through anal canal106to a position above anorectal junction104, and thereafter releasing retaining component200from the applied compressive forces—thereby allowing retaining component200to transition to its expanded state, in which expanded state, it naturally resists withdrawal through the narrower anal canal106.

As shown inFIG.4, first ends of collection component302and fluid delivery component304(each of which have an end affixed to or in proximity to retaining component200), respectively trail said retaining component200into the rectum, while opposite ends of said collection component302and fluid delivery component304pass through anal canal106and are located outside of rectum100.

As in the case of insertion, removal of retaining component200(and consequently of device300) from a subject's rectum requires application of forces that cause retaining component to transition from an expanded state to a compressed state having an orientation or cross-section sufficient to enable retaining component200to be withdrawn through anal canal106by application of withdrawing force. In an embodiment, retaining component200may be caused to change orientation or collapse into a sufficiently compressed state to enable withdrawal through anal canal106by application of (i) withdrawing force (in a direction distal to the rectum) at a plurality of points distributed around a periphery of retaining component200(which withdrawing force may be applied by one or more tethers provided on the periphery of retaining component200)—which causes retaining component200to collapse or transition to a collapsed state, whereinafter continued application of withdrawing force in a direction distal to the rectum causes retaining component200(and device300as a whole) to be withdrawn from the subject's rectum.

An embodiment of the invention is particularly configured to resolve certain serious shortcomings in other prior art devices that rely on annular retaining components to serve as indwelling components within a subject's rectum. Before discussing the specific invention embodiment, reference toFIGS.5A to5Dprovides information on the specific shortcoming that is sought to be resolved.

FIG.5Aillustrates a retaining component500of the kind observed in prior art devices is in its fully expanded state, and assumes a uniformly circular (or substantially circular) shape.FIG.5Bdemonstrates the effect of inwardly directed forces F along certain points on the circumference of said retaining component500, in that portions of the resilient member on which inward forces F are directed, deform inwards, while other portions are correspondingly deformed outwards. Since retaining component500in such prior art devices is a resilient ring, the respective inward and outward deformation is a consequence of the resilient properties of the constituting material.

FIG.5Cillustrates retaining component500in its fully expanded state when disposed within a subject's rectum. Adjacent rectal walls502are illustrated in a relaxed state, wherein no inwardly directed forces are applied on retaining component500. InFIG.5D, the rectal walls502are illustrated undergoing a peristaltic contraction, wherein inwardly directed radial forces F are applied at various points on the circumference of retaining component500. Since the inwardly directed compressive forces F are applied across the circumference of retaining component500, said member500is forced to collapse inwardly into one or more inward deformations, with a view to reduce the circumferential surface area presented by retaining component500adjacent to rectal walls502. The inward deformations create gaps between rectal wall502and circumference of retaining component500, through which fecal matter or fluid within the rectum can pass, leading to seepage or leakage along the outside of the device.

The invention addresses this problem through the specific constructional parameters of retaining component200.

As described above, retaining component200comprises a pliant and collapsible annular body202comprising a first material and a resilient ring204comprising a second material and embedded within or affixed to said annular body202. The first material used for the pliant and collapsible annular body202is different from and has different properties from the second material used for resilient ring204embedded within or affixed to annular body202. In an embodiment of the invention, resilient ring204is affixed to annular body202such that the outer periphery of retaining component200is entirely comprised of annular body202—i.e. said annular body202buffers the rectal anatomy from contact with resilient ring204at all points along the outer periphery of retaining component200.

In an embodiment of the invention, the first and second materials are selected to have different flexural modulus values—wherein the first material has a significantly lower flexural modulus than the second material. More specifically, the first material forming the pliant and collapsible annular body202has a flexural modulus of between 100 KPa and 100 MPa, while the second material forming the resilient ring204has a flexural modulus of between 20 GPa and 210 GPa.

In a more preferred embodiment, the first and second materials are additionally selected to have different durometers—wherein the first material has a significantly lower hardness than the second material. More specifically, the first material forming the pliant and collapsible annular body202has a durometer (or hardness) value of between 0 sh OO-70 sh A (based on Shore Durometer testing), and the second material forming the resilient ring204has a durometer (or hardness value) of between 40 HRB-70 HRC (based on Rockwell Hardness testing).

In an embodiment of the invention, the second material is any of one or more shape memory or superelastic alloys; various forms of spring metal such as steel, titanium, or beryllium copper; thermoplastic or thermoset polymers.

In an embodiment of the invention, the first material is any of absorbent materials; open cell or closed cell foams; and/or other natural or synthetic materials having elastic, resilient, and/or compliant properties.

In a yet more preferred embodiment of the invention, the retaining component200is configured such that the outward radial pressure exerted by resilient ring204is between 5 mmHg to 100 mmHg. Yet further, retaining component200may be configured so that the thickness of the first material between resilient ring204and an outer circumferential periphery of retaining component200is between 1 mm to 20 mm.

It has been found that by configuring retaining component200in accordance with the constructional embodiments discussed hereinabove and particularly owing to the selected differential properties of the first and second materials discussed above, even in cases where inwardly directed radial forces (for example peristaltic forces) are applied to retaining component200by adjacent walls of the rectal anatomy, and even in cases where non-uniform contact surfaces (for example overlap with rectal folds or residual stool) are not avoidable, collapsible annular body202is caused to compress and form inward indentations together with moving anatomy and non-uniform surfaces while ensuring to not separate from the adjacent rectal walls, while resilient ring204does not significantly change shape or orientation, acting as the main structure—thereby ensuring that patency of the fluid seal formed between the outer periphery of retaining component200and walls of the rectum is maintained—and preventing or minimizing leakage or seepage of fecal discharge or fluid that is contained within the rectum, outside of the device300for collection of fecal discharge.

FIG.6illustrates a preferred embodiment of the device300for collection of fecal discharge, comprising retaining component200and collection component302. In the illustrated embodiment, retaining component200comprises a plurality of vertically stacked ring structures212,214. Each of said plurality of vertically stacked ring structures212,214may comprise comprises a pliant and collapsible annular body comprising a first material and a resilient ring comprising a second material and embedded within or affixed to said annular body. It would be further understood that one or more than one or all of the vertically stacked ring structures212,214may be configured in accordance with any of the preferred features of construction that have described above in this specification, including based on the above described parameters for flexural modulus, durometer, thickness and radial pressure. By implementing a retaining component200having a plurality of vertically stacked ring structures212,214, theFIG.6embodiment ensures that even if particulate fecal matter or fluid within a subject's rectum leaks or seeps past the outer periphery of a first ring structure212, it would be prevented from continuing to leak or seep outside of the device300by the next ring structure214.

WhileFIG.6illustrates an embodiment comprising two vertically stacked ring structures212,214, it would be understood that any number of such ring structures may be arranged in a vertical stack.

While the exemplary embodiments of the present invention are described and illustrated herein, it will be appreciated that they are merely illustrative. It will be understood by those skilled in the art that various modifications in form and detail may be made therein without departing from or offending the spirit and scope of the invention as defined by the appended claims. Additionally, the invention illustratively disclose herein suitably may be practiced in the absence of any element which is not specifically disclosed herein—and in a particular embodiment that is specifically contemplated, the invention is intended to be practiced in the absence of any one or more elements which are not specifically disclosed herein.