WO2018083451A1

WO2018083451A1 - Improvements to a bolus, an enteral tube and/or a catheter

Info

Publication number: WO2018083451A1
Application number: PCT/GB2017/053245
Authority: WO
Inventors: Iden Shams
Original assignee: Gbuk Group Limited
Priority date: 2016-11-04
Filing date: 2017-10-27
Publication date: 2018-05-11
Also published as: GB2555611A

Abstract

Improvements to a bolus, an enteral tube and/or a catheter Improvements to a bolus, an enteral tube and/or a catheter Improvements to a bolus, an enteral tube and/or a catheter Improvements to a bolus, an enteral tube and/or a catheter A bolus suitable for enteral feeding is disclosed having a generally tubular body incorporating a side wall, a posterior end adapted for attachment to the downstream end of a feeding tube or integrally formed therewith, and an anterior end; the bolus further comprises at least two fluid openings in the side wall disposed substantially opposite one another along an axis of the bolus, and wherein at least a portion of a septum is disposed between the fluid openings, the septum having curved side walls which diverge along the axis from an apex of the septum towards the anterior end of the bolus.

Description

Improvements to a bolus, an enteral tube and/or a catheter

Field of the Invention The invention relates to a bolus suitable for enteral feeding. The invention also relates enteral feeding tubes and/or catheters.

Background to the invention

Adequate nutrition and medication are of key importance in patient recovery. In patients who are unable to swallow or take adequate nutrition or medication orally, a nasogastric or nasojejunal feeding tube is often used to deliver nutrients or medication directly into the gastrointestinal tract. Enteral feeding has few complications and is low cost compared with parenteral nutrition which is associated with a high complication rate and high cost.

If the patient has a functioning gastrointestinal tract, the feeding tube is inserted through the nose into the stomach or small intestine via the pharynx and oesophagus. Correct positioning of the feeding tube is verified by aspirating gastric juice which is tested using pH paper. The patient can then receive nutrition via the feeding tube.

US-A-651 1474 discloses a feeding tube with an outlet port in a rigid bolus which is larger than the French gauge of the feeding tube. The rigidity of the bolus increases the risk of lung puncture during placement. The feeding tube has only one outlet which may get sucked onto the internal abdominal wall during aspiration of gastric juice and which therefore makes it difficult to confirm correct positioning. The outlet port is wider than the actual feeding tube which makes it more uncomfortable to place and causes a safety concern when used with securing devices such as a Corgrip™ or Nasal Bridle™. US-A-4516970 discloses a device having a tube element with openings therein to avoid stagnation of a fluid within the device.

Summary of the Invention

In a first broad independent aspect, the invention provides a bolus suitable for enteral feeding comprising a generally tubular body incorporating a side wall, a posterior end adapted for attachment to the downstream end of a feeding tube or integrally formed therewith, and an anterior end; wherein said bolus further comprises at least two fluid openings in the side wall disposed substantially opposite one another along an axis of the bolus, and wherein at least a portion of a septum is disposed between the fluid openings, the septum having curved side walls which diverge along the axis from an apex of the septum towards the anterior end of the bolus.

The septum itself may be generally solid. In relation to the septum the term side walls generally refers to an outer surface of the septum. The side walls of the septum join at the apex of the septum. This is particularly advantageous because having two fluid openings reduces the possibility that the enteral feeding tube becomes blocked with food or debris, as if one opening becomes blocked then there is still a second opening. In addition, when attempting to place a nasogastric enteral feeding tube, the test to determine whether the tube is in the correct location is the aspiration and pH testing of gastric fluid. In prior art, when only one opening exists in the wall of the bolus, the pressure created during the aspiration process could cause the bolus to suction onto a surface or organ within the body, potentially damaging it. Having two holes reduces the possibility of suction attachment to an internal surface during aspiration. Furthermore, the present arrangement directs the flow of fluid towards the fluid openings gradually to minimise turbulence and therefore optimising flow rate whether in fluid dispensing mode or in fluid aspirating mode. The arrangement ought also to evenly divide the stream of food or nutrients and deliver them evenly to the fluid openings, improving distribution.

Yet further the disposing of the at least two fluid openings on opposite sides of the bolus means that there is even less chance of the bolus becoming attached to an internal surface or organ during aspiration, as the hole on the opposite side would release the pressure preventing damage. In addition, having holes on opposite sides of the bolus ensures, in certain embodiments, even distribution of foodstuffs and or medication to the site of delivery.

Optionally, one or more fluid openings are provided as a recess in the side walls; the recess comprising an outermost rim with opposite edges which adjoin the outermost regions of said first and second curved sides.

Optionally, said apex is rounded. This is particularly advantageous in order to reduce the likelihood of any feed being blocked on a sharp edge.

Optionally, one or more fluid openings are provided as a recess in the side walls; the recess comprising an outermost rim with opposite edges which converge in the longitudinal axis of the bolus. This aspect further assists in the insertion process as the shape and configuration of the bolus facilitates its displacement to the location for feeding nutrients and/or for aspirating as appropriate.

Optionally, said outermost rim is substantially triangular when viewed in side elevation. This configuration also improves the ease with which the bolus may be displaced to its location of use.

Optionally, opposite edges of said outermost rim converge and intersect one another.

Optionally, said outermost rim is substantially perpendicular to the longitudinal axis of the bolus. This configuration is particularly advantageous in order to allow the fluid to exit the bolus in a direction perpendicular to the longitudinal axis of the bolus.

Optionally, the forward most portion of the bolus comprises no aperture. This is particularly advantageous because the edges of any such aperture could snag as the bolus is being inserted and cause damage or discomfort. Optionally, said posterior end incorporates an attachment shank, said attachment shank being suitable for insertion into a feeding tube. This is particularly advantageous because the point of attachment between the bolus and the feeding tube is susceptible to kinking. Providing an attachment shank at this location helps reduce the possibility of kinking. Optionally, said body comprises an annular flange of substantially identical outer diameter to the outer diameter of a feeding tube so that, in use, when a feeding tube is fitted to said attachment shank, said flange abuts the downstream end of the optionally fitted feeding tube without the tube protruding beyond said flange. This is particularly advantageous because it prevents a step existing between the tube and the bolus which may snag causing internal damage or discomfort.

In a second broad independent aspect, the invention provides a feeding tube comprising a bolus in accordance with any one of the preceding aspects.

In a third broad independent aspect, the invention provides a catheter comprising a bolus in accordance with any one of the preceding aspects.

Brief Description of the Figures

Figure 1 shows a first embodiment of a bolus is cross section side perspective view. Figure 2 shows a first embodiment of a bolus in perspective view. Figure 3 shows a first embodiment of a bolus in rear perspective view. Figure 4 shows a first embodiment of a bolus in a cross sectional side view. Figure 5 shows a first embodiment of a bolus in perspective view.

Figure 6 shows a first embodiment of a bolus in a second perspective view.

Detailed Description of the Figures In an embodiment, the invention provides a bolus designed and configured to be used in conjunction with a standard tube, such as a French tube, for use as part of an enteral feeding apparatus. The bolus may assist in the delivery of food to patients via enteral feeding apparatus. In addition, the bolus may prevent the feeding tube from becoming blocked with foodstuffs and other debris, and may also assist in effective aspiration of stomach acid and the like. It should be understood that although the description is made with specific reference to enteral feeding tubes and in particular nasogastric enteral feeding tubes, this is by way of example only. Further embodiments envisage the combination of a bolus with catheter tubes and then means of enteral feeding, such as; nasogastric, nasojejunal, nasoduodenal. Further embodiments provide a bolus which is integral with a tube or duct.

The term bolus is used to describe a downstream attachment to a tube which is shaped and configured to be suitable for inserting into a patient. It forms, in other words, a cap which is shaped and configured with a forward most atraumatic tip. In preferred embodiments, the forward most tip is part spherical or rounded. In further preferred embodiments, the forward most portion of the bolus is filled with solid material. In further preferred embodiments, the diameter of the bolus is no more than the diameter of a tube with which it operates in use.

To provide clarity, the elements of the invention which are common to each figure have retained identical numerical references throughout.

Figures 1 -6, show a first embodiment of a bolus 10 configured and adapted for use with a feeding tube, such as a French tube (not shown). The bolus 10 can be configured to conform to any size French tube but for consistency the current embodiment of the bolus 10 will be described as configured for a size 8 French tube. The bolus 10 has an anterior head 14, a medial dividing portion 13 and a substantially tubular posterior body 12. The body 12 has a substantially cylindrical outer surface or diameter 17 and a substantially cylindrical inner surface or diameter 18, centred around a central axis 20. At the posterior end of the body 12 is a cylindrical attachment shank 22. The attachment shank 22 has a substantially cylindrical inner surface or diameter 23 and a substantially cylindrical outer surface or diameter 24, both centred around axis 20. The inner surface 23 of the attachment shank 22, is in continuous attachment with the inner surface 18 of the body 12. The inner surfaces 18 and 23 cooperate to define the main channel 11 with aperture 26 proximal to the French tube and aperture 27 proximal to the dividing portion 13. The attachment shank 22 is adapted to be attached to the

downstream end of a French tube. The main channel 11 forms a fluid tight attachment with a French tube, so that, in use, the contents of the French tube can pass from the aperture 26, through the main channel 11 and out of the aperture 27. The term fluid includes for the avoidance of any doubt, granulated or powder compounds that are capable of flowing down tubing.

The diameter of the attachment shank 22 may be tapered by an angle of less than 10%, preferably 6%, so that, in use, the attachment shank 22 can be fitted into the free, downstream end, of the French tube, creating a frictional attachment and seal. The outer diameter of the body 12 and the diameter of the outer surface of the French tube are substantially identical, so that, in use, the feeding tube apparatus has a continuous exterior profile and no step exists between the outer surface 17 of the body 12 and the external diameter of the attached French tube. This serves to prevent internal snagging and discomfort for the patient during intubation. In addition, in use, the downstream end of the French tube circumferentially abuts the ledge 21 at the posterior end of the body 12. The diameter of the ledge 21 is defined as half the difference in the diameter of the outer surface 17 of the body 12 and the outer surface 24 of the attachment shank 22. The width of ledge 21 should be substantially identical to the width of the French tube to be used. This helps to prevent internal snagging and may provide an increased seal.

The end of the attachment shank 22 proximal to the French tube, forms a planar ring 25. The ring 25 has a width defined by half the difference between the diameter of the outer surface 24 and the inner surface 23. In a preferred embodiment, the inner surface 23 of the attachment shank 22, may taper outwards towards the outer surface 24, reducing the width of the ring 25. Alternatively, the confluence of the inner surface 23 and the ring 25 could be chamfered. This change in angle or reduction in the width of the ring 25 reduces the potential for food to become trapped against the ring 25, and reduces the potential for the feeding tube becoming blocked.

Preferably, the head 14 of the bolus 10 is smooth and rounded to prevent internal snagging and discomfort to the patient during intubation. In a preferred embodiment, the head 14 can be sized and weighted to provide optimal conditions for intubation, depending on the desired location of the feeding tube. The bolus 10 incorporates two substantially identical fluid openings 30 and 31, disposed on opposite sides of the bolus 10. The fluid openings 30 and 31 are substantially opposite one another, equally distributed along the horizontal axis of the bolus 10.

As fluid passes out of the aperture 27 of the main channel 1 1, it enters the medial dividing portion 13, where it is diverted from the central horizontal plane by a septum 32. The septum 32 is a horizontal dividing wall with apex 33 forming a medial division across the diameter of aperture 27 of the main channel 1 1. The septum 32 has curved side walls 34 and 35 which diverge along the axis 20 from apex 33 of the septum 32 towards the anterior end 14 of the bolus 10 leading to fluid openings 30 and 31 respectively, in the side wall of the bolus 10.

Fluid openings 30 and 31 are characterised by recesses in the side wall 17 of the bolus 10. Fluid opening 30 has an outermost rim with side edges 36 and 37 which tend towards each other at the anterior end, adjoining at point 40. Fluid opening 31 has an outermost rim with side edges 38 and 39 which tend towards each other at the anterior end, adjoining at point 41. In the current embodiment, the outermost rims of the fluid openings 30 and 31 are broadly isosceles triangles, with an apex at the anterior end. In an alternative embodiment, the outermost rim of the fluid openings 30 and 31 could be square, oval, circular or any other suitable shape. The base of the recesses of fluid openings 30 and 31 are defined by the curved side walls 34 and 35 of septum 32, which curve from apex 33 to intersect with the outermost rims of the fluid openings 30 and 31, respectively.

The septum 32 has a substantially bell curved shape with side walls 34 and 35 following horizontally symmetrical, sigmoidal paths. The confluence of the side walls 34 and 35 of the septum 32 and the outermost rims of the fluid openings 30 and 31 are precipitous. Optionally, the apex 33 of the septum 32 is a gentle convex curve. As the fluid enters the medial dividing portion 13 it is diverted by the apex 33 of the septum 32, diverting half the fluid or granulated solid in an upwards direction (as oriented in figure 1), and half the fluid in an opposite downwards direction. The separated streams, travel along curved surfaces 34 and 35 respectively, which direct the flow towards the fluid openings 30 and 31. The curved surfaces 34 and 35 of the septum 32 are optimized to increase fluid flow through fluid openings 30 and 31 respectively. The upward curvature may be sufficient to guide the fluid from the central axis 20 to the fluid openings 30 and 31. However, if the curvature is too severe then it may obstruct the flow of fluid and result in a decrease in the flow output. Optionally, the curved surfaces 34 and 35 of the septum 32 may have a more severe angle of curvature as they tend towards confluence with the outermost rim of the fluid openings 30 and 31. This has the added benefit of ensuring the fluid exits the bolus 10 in a direction perpendicular to axis 20.

The bolus 10 and a French tube may optionally be secured by an adhesive which provides a gap-free joint between the outer surface 24 of the shank attachment 22 and the inner surface of the French tube. In an alternative embodiment, the outer surface 24 of the shank attachment 22 incorporates a number of recesses, which, in use, act as fluid reservoirs and increase the surface area for bonding. Adhesive is applied along the length of the attachment shank 22, which provides support and resistance to kinking across the main channel 1 1 at the downstream end of the French tube. This is an area that would otherwise represent the weakest part of the French tube and most prone to kinking. In an embodiment, an endoscopic camera may be incorporated into the anterior head 14 of the bolus 10. This has the added benefit of assisting the process of guiding the feeding apparatus into the correct location without the use of radiological assistance. This may be beneficial for nasojejunal and nasoduodenal placements which cannot use aspiration of gastric fluids as an indicator of correct placement. The camera may be wirelessly configured to transmit the images to an external monitor that could be viewed by the practitioner fitting the enteral feeding tube. This may also be of benefit for the localised and targeted application of medication to areas such as ulcers. The camera may allow the practitioner to target the medication with greater accuracy than a traditional

administration means.

Claims

1. A bolus suitable for enteral feeding comprising a generally tubular body incorporating a side wall, a posterior end adapted for attachment to the downstream end of a feeding tube or integrally formed therewith, and an anterior end; wherein said bolus further comprises at least two fluid openings in the side wall disposed substantially opposite one another along an axis of the bolus, and wherein at least a portion of a septum is disposed between the fluid openings, the septum having curved side walls which diverge along the axis from an apex of the septum towards the anterior end of the bolus.

2. A bolus according to claim 1, wherein one or more of the said fluid openings are provided as a recess in the side walls; the recess comprising an outermost rim with opposite edges which adjoin the outermost regions of said curved sides of the septum.

3. A bolus according to either claim 1 or claim 2, wherein said apex is rounded.

4. A bolus according to any of the preceding claims, wherein one or more of the said fluid openings are provided as a recess in the side walls; the recess comprising an outermost rim with opposite edges which converge in the longitudinal axis of the bolus.

5. A bolus according to claim 4, wherein said outermost rim is substantially triangular when viewed in side elevation.

6. A bolus according to claim 4, wherein said opposite edges converge and intersect one another.

7. A bolus according to any one of claims 4 to 6, wherein said outermost rim is

substantially perpendicular to the longitudinal axis of the bolus.

8. A bolus according to any of the preceding claims, wherein the anterior portion of the bolus comprises no aperture.

9. A bolus according to any of the preceding claims, wherein said posterior end

incorporates an attachment shank, said attachment shank being suitable for insertion into a feeding tube.

10. A bolus according to claim 9, wherein said body comprises an annular flange of substantially identical outer diameter to the outer diameter of a feeding tube so that, in use, when a feeding tube is fitted to said attachment shank, said flange abuts the downstream end of the optionally fitted feeding tube without the tube protruding beyond said flange.

1 1. A feeding tube comprising a bolus in accordance with any of the preceding claims.

12. A catheter comprising a bolus in accordance with any of claims 1 to 10.