METHOD FOR INTERMITTENTLY TRIGGERING A REFLEX-COORDINATED DEFECATION
20180311479 · 2018-11-01
Inventors
Cpc classification
A61M2025/09116
HUMAN NECESSITIES
A61M3/0245
HUMAN NECESSITIES
A61M2025/105
HUMAN NECESSITIES
A61M25/10181
HUMAN NECESSITIES
A61M2025/0687
HUMAN NECESSITIES
A61M2025/1052
HUMAN NECESSITIES
International classification
A61F2/00
HUMAN NECESSITIES
Abstract
The invention relates to a method for filling an inflatable catheter balloon of a device for transanally introducing an infusion into the rectum or colon of a patient by means of a filling device, wherein a fill volume or a filling pressure prevailing in the catheter balloon is until there occurs a gradual, user-controllable, pneumatically initiated expansion of portions of the bowel wall, thus triggering a coordinated defecation reflex, wherein the timing and intensity of the triggering stimulus can be determined to the greatest possible extent by the user.
Claims
1.-20. (canceled)
21. A method for filling an inflatable, catheter balloon of a device for transanally introducing an infusion into the rectum or colon of a patient by means of a filling device, wherein a fill volume or a filling pressure prevailing in the catheter balloon is increased by pumping air or another gas into the catheter balloon until there occurs a gradual, user-controllable, pneumatically initiated expansion of portions of the bowel wall, thus triggering a coordinated defecation reflex, wherein the timing and intensity of the triggering stimulus can be determined to the greatest possible extent by the user.
22. The method according to claim 21, wherein a catheter balloon is used which consists of an only slightly volume-expandable (compliant) material or of a non-volume-expandable material.
23. The method according to claim 22, wherein a catheter balloon is used which consists of polyurethane (PUR).
24. The method according to claim 22, wherein a catheter balloon is used which consists of polyethylene, PVC or mixtures of the aforesaid materials with polyurethane.
25. The method according to claim 21, wherein a catheter balloon is used which is preformed to its working dimensions, especially in an enlarged balloon segment adapted for being placed intrarectally, and/or in a tapered balloon segment adapted for being placed transanally.
26. The method according to claim 21, wherein a fill volume or a filling pressure prevailing in the catheter balloon is increased in two or more steps.
27. The method according to claim 21, wherein the pressure in the transanally placed catheter balloon is initially set to a first, low pressure range, preferably of approximately 10 to 25 mbar, which primarily anchors and seals the catheter in the anus of the patient.
28. The method according to claim 21, wherein an inflow fluid is introduced into the rectum of the patient.
29. The method according to claim 28, wherein the inflow fluid is introduced into the rectum of the patient by squeezing it out of a connected container.
30. The method according to claim 27, wherein, after a suitable retention time, the filling pressure in the catheter balloon is raised, preferably to approximately 30 to 60 mbar, causing only the rectal bowel wall of the patient to be initially included in the expansion, and at which the defecation reflex is triggered in most users.
31. The method according to claim 27, wherein, upon a further increase in the filling pressure in the catheter balloon, preferably to approximately 60 to 120 mbar, the anal canal of the patient is also caused to expand, which in many cases substantially increases the intensity of the stimulus triggering the defecation reflex.
32. The method according to claim 21, wherein, by a sequential pneumatic triggering of a defecation reflex, a volume of the irrigation fluid is reduced to a value of approximately 80 to 120 ml per administration, or to a volume smaller than that.
33. The method according to claim 32, wherein the fluid is delivered as ready-to-use solution through a preferably fixed feed conduit to the catheter, as a disposable product.
34. The method according to claim 21, wherein the necessary amount of an infusion fluid is reduced by the pneumatic expansion stimulus that can be well controlled by the user.
35. The method according to claim 21, wherein the catheter further comprises a preferably fixedly glued-in filling conduit for charging the catheter balloon with filling pressure.
36. The method according to claim 21, wherein a unit for filling the balloon is implemented in reusable form.
37. The method according to claim 36, wherein the unit for filling the balloon is configured as a hand-operated pump balloon connectable via a coupling.
38. The method according to claim 36, wherein the unit for filling the balloon is configured as a pumped balloon with a pressure-indicating manometer.
39. The method according to claim 38, wherein the pressure-indicating manometer has a scale which displays one or more pressure ranges, recommended for the various filling steps when applying the device.
40. The method according to claim 21, wherein the filling of the balloon is volume-controlled.
41. The method according to claim 40, wherein the volume-controlled filling is achieved by use of a syringe element.
42. The method according to claim 41, wherein the syringe body comprises a suitable marking that specifies the preferred fill volume.
43. The method according to claim 21, wherein the catheter shaft is equipped in the proximal, preanal region with gripping depressions, to accommodate the fingers gripping the catheter during insertion and to ensure the most practicable and save catheter insertion possible.
44. The method according to claim 43, wherein gripping depressions are disposed on the catheter shaft in direct proximal adjacency to a rear fixation line of the catheter balloon.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0030] Further features, characteristics, advantages and effects of the invention will become apparent from the following description of preferred embodiments of the invention and by reference to the drawing. Wherein:
[0031]
[0032]
[0033]
[0034]
[0035]
[0036]
[0037]
[0038]
[0039]
[0040]
[0041]
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0042]
[0043] The balloon 2 terminally comprises two balloon shaft ends (6, 7) for attaching the balloon to the shaft. During the mounting of the balloon, the shaft ends 6 and 7 are invaginated (inverted) into the inside of the balloon by a defined magnitude B and in this position, in which they are displaced toward each other, are fixed on the shaft 1, for example by gluing or welding.
[0044] The sum of the magnitudes B of the inversions at both ends should be at least equal to the length of the tapered intermediate piece A (A smaller than/equal to the sum of the magnitudes B).
[0045] The inversion depth B at the end of the balloon facing the patient or the rectum corresponds to the distance from the apex 8 of the distal, intrarectal balloon radius 9 to the distal fixation line 11 of the balloon end 6 on the catheter shaft.
[0046] The distal radius 9 corresponds to the frontal radius during free, non-inverted unfolding of the completely filled but not pressurized balloon (broken line). An exemplary rule for geometrically determining the apex 8 to good approximation is illustrated in
[0047] It can be seen in
[0048] On the side of the balloon facing away from the patient, the inversion depth B corresponds to the distance from the apex 12 of the proximal, preanal balloon radius 13 to the proximal fixation line 14 of the balloon end 7 on the catheter shaft.
[0049] Radius 13 corresponds to the proximal radius when the balloon is freely unfolded without inversion. The geometric determination of apex 12 is similar to the approximation described in
[0050] The length of intermediate piece A is determined by determining the distance between the transitions of the shoulder radii 15 and 16 (inflection points) of the mutually facing shoulder surfaces of balloon segments 4 and 5.
[0051] The inversion depths, lengths and distances are each determined in the filled state under filling pressure, the filling pressure being so selected that the balloon unfolds completely but there is no elastic expansion of the balloon envelope.
[0052] The inversion depth B is calculated as follows: B>=A/2 (>=represents greater/equal).
[0053] In mounting the balloon on the catheter shaft, the respective points for the inversion of each of the balloon shaft ends are the apex 8 of the distal, intrarectal balloon radius 9 and the apex 12 of the proximal, preanal balloon radius 13.
[0054] In the embodiment described in this figure, the distal fixation line 11 also corresponds to the distal end of the catheter shaft 1. The shaft terminates directly at the fixation line 11 and does not extend distally past this fixation line in the manner illustrated in
[0055]
[0056] The forward balloon radius 9, frontally facing the intestinal lumen, of the intrarectal balloon segment 4 is illustrated as a broken line. It is constructed from the two inflection points 9a and 9b and the two inflection tangents 9c and 9d respectively belonging to these inflection points.
[0057] One of the two inflection points 9a or 9b is used to construct a straight line 9e or 9f that is normal to the respective inflection tangent 9c or 9d and intersects the corresponding inflection point 9a or 9b. The point of intersection of these straight lines 9e or 9f with the axis X of symmetry yields the center point of the circle K.
[0058] The circle K, and thus the forward balloon radius 9, results from the center point M of the circle and the inflection points 9a and 9b, which are on the circumference of the circle. In this derivation, apex 8 is obtained from the point of intersection of the circumference of the circle with the axis X of symmetry of the balloon.
[0059] For the description of the frontal apex 8 used below, the derivation of the farthest distally ranging point of the filled, unpressurized balloon envelope is performed, for purposes of simplification, using the point of intersection of the connecting line Z between the two inflection points 9a and 9b with the axis X of symmetry.
[0060]
[0061] In a preferred, particularly thin-walled and soft-film-like implementation of the balloon body, the two segments move toward each other in response to the slightest, nearly ambient filling pressure and roll over the middle segment 3. When the two segments are in contact in the region of the transition points (15, 16) of the shoulder radii, the apex 8 of the radius 9 is flush or nearly flush with the distal fixation line 11 of the distal balloon shaft end 6 on the catheter shaft.
[0062] A configuration of this kind would correspond in situ to a clinical use situation in which the anal canal was maximally shortened in length. Even in this extreme case, it would thus be ensured by virtue of the described inversion rule that the free distal catheter shaft end, which here corresponds to the distal fixation line 11, does not extend into the intestinal lumen and even in the event of maximal lateral deflection of the catheter shaft in the rectum (tilting of the intrarectal portion of the shaft toward the bowel wall) does not come into contact with the wall of the intestine and pass beyond the distal balloon radius 9, as a maximum limit precluding irritation and lesions of the bowel wall.
[0063]
[0064] The mere individual intra-abdominal pressure bearing against the transanally placed balloon or acting on the balloon is sufficient to produce a combined transanal sealing effect, comprised of radial sealing with respect to the anal canal and axially oriented sealing brought about by the counter-rolling movement of the terminal balloon enlargements at the inner and outer outlets of the anus. The sealing effect thus is not contingent on the balloon initially being filled beyond its volume and unfolding freely until the balloon envelope begins to expand. The balloon can behave in the described axial counter-rolling and radial unfolding fashion, even under partial filling of, for example, 70 to 90% of its volume when freely unfolded on the catheter shaft. This enables the balloon catheter to be placed in the anus in a nearly pressure-neutral and irritation-free manner.
[0065] In the presence of normal or slightly modified anal anatomy, any traumatizing effect of the tip of the catheter shaft on the bowel wall can thus be precluded, even under completely pressure-neutral charging with a filling medium, by the inversion of the shaft tip that occurs according to the invention.
[0066]
[0067] Length B is increased in comparison to
[0068] The corresponding inversion depth B is preferably calculated taking into account a tip piece in the form: B>=A/2+C.
[0069] Alternatively hereto, the corresponding inversion depth B can, less preferably, be obtained considering a tip piece according to the relation: B>=A/2+C/2.
[0070]
[0071] This rule particularly considers a possible axially oriented deflection of the catheter shaft inside the filled, transanally placed balloon. In the context of the inventively described inversion of the balloon shaft ends on the catheter shaft supporting the balloon, such deflection of the shaft in the longitudinal axis could cause the distal end of the catheter shaft to be deflected toward the bowel, thus creating a potential risk of perforation.
[0072] The maximum distal deflection W of the forward fixation line 11 is defined as a distance that emanates from the apex 8 of the radius 9, forming a distally directed prolongation of the longitudinal axis of the shaft, and extends to the apex 20 of a radius 21, said radius 21 being constructed over the largest diameter D of the intrarectal balloon segment 4.
[0073] If the catheter shaft has a tip piece 18 that extends beyond line 11, the maximum deflection path W should be correspondingly selected so that upon maximum deflection W of the shaft, the tip 19 of the tip piece does not extend past radius 21.
[0074] The radius 21 defined by the largest diameter D in the intrarectal balloon segment constitutes a fundamentally relevant boundary line for distal portions of the catheter shaft. In the event of lateral tilting of the shaft longitudinal axis of the transanally placed catheter shaft, the fact that the maximum deflection W is referred to the largest balloon diameter D ensures that the catheter shaft tip (11, 19) still moves within the pivot radius 21 of balloon segment 4, thus preventing relatively well any potential traumatizing contact of the tip with the bowel wall adjacent the balloon.
[0075] In determining the inversion depth B, the particular ratio of the distance W to the radius 21 or of the diameter D on which it is based is preserved and the inversion depth B is adjusted accordingly as necessary.
[0076]
[0077] In this state, the two envelope portions preferably come to lie approximately at the height of the line segment between the fixation points of the balloon ends 6 and 7 on the surface of the shaft. The envelope of the preanal balloon segment 5, by contrast, is preferably smoothed out in the proximal direction and protrudes past the fingers gripping the catheter for insertion, the preferred gripping point being located just proximal of the proximal fixation line 14. The gripping point 22 is preferably implemented as a depression-like receiving surface, one such preferably being provided on each of the opposite, 180-apart shaft surfaces.
[0078] The evacuated balloon being fixed in such fashion, the user grips with his fingers under the envelope of segment 5, which envelope is smoothed out in a proximal direction, and guides the catheter into the rectum until the gripping fingers abut the external anus. A defined insertion depth is thereby ensured. It is further ensured that the intrarectal balloon section 4 is inserted into the rectal cavity, while the proximal balloon portion 5 comes to lie outside the anus (preanally). Reliable transanal positioning of the catheter therefore occurs as the waisted balloon is filled.
[0079]
[0080] In a particularly large-volume implementation of the intrarectal balloon segment or a longitudinal expansion of the balloon segment that reaches far into the rectum, the balloon segment, in the non-air-filled, ready-to-use state, can optionally be stuffed or packed partially into the opening 24. It then slips out of the opening as the inserted catheter is filled.
[0081] Given suitable implementation of the shaft material, the waist 23 can also predefine a certain kinkability of the shaft body, thus improving its atraumatic properties.
[0082] The filling of the balloon takes place through a separate duct 26 integral to the shaft.
[0083] To prevent backflow of irrigation fluid, the inflow catheter can is [sic] equipped with a non-return valve in the region of the fluid-conveying duct 25.
[0084] The valve can preferably consist of a thin-walled tube element having a wall thickness of few, preferably, 5 to 15 micrometers and the diameter of the duct 25, the distal end of the tube lying freely in the duct 25 over a length of approximately 5 to 10 mm and its proximal end being connected sealingly to the inner wall of the duct 25. As the medium flows through the duct in the direction of the tip, the tube element opens and allows the medium to flow freely. In response to flow in the reverse direction, the tube element collapses and closes up sealingly, preventing an effective backflow.
[0085]
[0086] When the user then initiates an increase in the filling pressure in the balloon into range 30 (30-60 mbar, with increasing corresponding expansion of the rectal portions of the bowel wall) or into range 37 (60-120 mbar, with increasing additional expansion of the anal sphincter), the user is ultimately able to generate a trigger stimulus of largely reproducible intensity in order to trigger a defecation reflex. The user thus has the advantage of being able to avoid an evacuation reflex in the presence of an initially low balloon pressure merely having an anchoring and sealing action, and thus of being able to retain the infusion fluid in the bowel long enough for his individual needs, resulting in better dissolution or suspension of stool in the fluid. On the other hand, by intentionally causing an increase in pressure in the balloon, he can generate an intense, relatively prompt-acting reflex-triggering stimulus, which can, if necessary, exceed in intensity the triggering effect of a column of colorectal fluid.
[0087] The catheter balloon is preferably filled with air, through a fill line integrated into the shaft wall of the catheter body 1.
[0088] In addition to pressure-controlled filling of the balloon using a pump manometer, as illustrated in
[0089] A volume-controlled filling of the balloon can also be a two-step process, in which incomplete filling is first performed and the balloon is then, in the second filling step, filled with a volume that has a triggering effect. The pressures developed in the transanal balloon in response to the particular volume should preferably fall within the pressure ranges (29, 30) described in
[0090] To limit the filling pressure or prevent critically high balloon filling pressures, in the case of both manometer- and syringe-actuated filling a pressure limiting valve 31 can be interposed between the filling element and the catheter, to prevent, for example, balloon filling pressures over 120 mbar.
[0091]
[0092] The volume of the container 33 must be dimensioned in this case to accommodate approximately 80 to 120 ml of irrigation solution. The relatively small quantity is squeezed out manually by the user and thus introduced into the rectum by repeated squeezing. To make it possible to grip the container even with impaired hand motor function, the container is preferably shaped as cylindrical, with a diameter of approximately 4-6 cm.
[0093] Connection 32 is preferably equipped with a seal 35 that can be broken by bending and that releases the irrigation solution. It is also advantageous to provide a non-return valve 36, which is integrated into the fluid-conveying arm of the ready-to-use device and which permits the directed emptying of the container without backflow.
[0094] Another feed conduit 34 can be connected directly to a pump manometer 27 or a filling syringe.
[0095] The balloon element 2 consists of a thin-walled soft film in the wall thickness range of 5 to 100 micrometers. Films in the thickness range of 5 to 40 micrometers are advantageous. Wall thicknesses of 5 to 15 micrometers, on the other hand, are particularly preferable.
[0096] The use of only slightly volume-expandable materials, such as, for example, polyurethane (PUR), for example of the specification Pellethane 2363 80A to 90A, Dow Chemical Corp., is preferred, since these materials have good dimensional stability in the lowest wall thickness range, including as balloon films, in the pressure range of approximately 10 to 120 mbar.
[0097] Such thin-walled PUR balloon films formed into complex shape can preferably be produced by hot molding from previously extruded raw tubing material, which, with suitable stretching of the tube blank before tempering, permits a polymer orientation and lends the shaped balloon films exceptional mechanical strength.
[0098] It is also conceivable to use polyurethanes of low Shore hardness, for example in the range of 60 to 75A, to impart a volume-expandable behavior, with a relative loss of dimensional stability, to the catheter balloon in the wall thickness range of less than 40 m, and preferably less than 15 m, in the typical filling pressure range during use of 10 to 120 m.
[0099] Alternatively, for example non-volume-expandable materials can also be used, such as polyethylene, PVC or mixtures of the aforesaid materials with polyurethane.
[0100] Balloon films according to the invention can also be shaped directly from the extruded, still soft, largely amorphous tube molding compound (in-line molding), in which case the achievable strengths of the films are much lower than those of pre-extruded tubes and the attainable wall thicknesses are much higher than in the case of forming from pre-extruded material.
[0101] Dipping processes using liquid PVC or PUR materials can also be contemplated for production.
[0102] The welding together of single layers of film to form balloon bodies is also conceivable.
[0103] The connection of the balloon to the shaft body is effected by gluing, by thermal methods, or alternatively by shrinking the balloon ends onto the shaft body.
[0104] In the freely unfolded, unpressurized state, the balloon should preferably have a diameter of approximately 30-60 mm in the intrarectal section 4, approximately 10 to 30 mm in the middle, waisted region 3, and approximately 30-50 mm in the preanal region 5. The middle segment 3 should have a length of approximately 20-40 mm and each of the terminal segments 4 and 5 a length of approximately 20-40 mm.
[0105] If, as a special measure for sequential filling, the catheter balloon is provided with optional intrarectal balloon triggering, the intrarectal balloon section 4 in the freely unfolded, unpressurized state preferably has a diameter of approximately 40-80 mm and a length of preferably 30-60 mm.
[0106] In addition to the transanal use of the inflow catheter, the embodiments according to the invention can also be used for perforation-safe placement of a transanally inserted drainage tube for, among other purposes, the ongoing drainage of stool from a patient's intestine. Further, the described catheter technique may also be contemplated for use in surgically created stomata/openings or other natural body openings.