The present invention relates to a connector for connecting a supply tube for an enteral feeding solution to a gastrostomy device.
Patients with chronic conditions such as certain neurologic and neuromuscular disorders, malformations of the mouth and oesophagus, as well as critically ill patients in intensive care units or patients recovering from surgery are often unable to suck or swallow and may therefore be unable to take adequate nutrients or medicines orally. In these situations a gastrostomy device is implanted in a patient's stomach wall to provide nutrition (and in some cases medication) directly into the stomach.
The gastrostomy device can be a long tube (e.g. a PEG tube) which includes a tube portion which extends outside the patient's body. These types of tubes are typically used initially or over shorter time periods. For longer term enteral feeding, low profile (e.g. “button”) tubes are often used. These have a low profile “button” connector which lies fairly flush against the patient's body. A feeding tube can then be attached to the button connector to administer nutrition or medication when required. The lack of a permanent external tube makes button tubes more attractive for long-term enteral feeding as the risk of snagging is reduced, and the button is less visible and can more easily be concealed under clothing. Balloon buttons (which are held in place by a fluid-filled balloon) can also be replaced at home after training, without medical assistance.
Feeding tubes typically have a male connector on the end which mates with a female port on the button connector. Existing male connectors such as the connector disclosed in GB2586690A typically include a tapered nozzle end which is pushed into the button connector to open a non-return valve (such as a duckbill valve) and allow feed to pass through. The tapered nozzle end reduces friction and wear on elastomeric parts (such as the non-return valve and sealing ring) during insertion and removal of the device. However, the tapered male connector could mate with or be pushed into a female connector of the incorrect (i.e. smaller) size. A patient may have multiple connectors of different sizes, each of which performs a different function (such as provision of medication, fluid draining etc). A misconnection could lead to feed or medication being provided through the wrong portal (such as an IV line), with potentially lethal results. Such misconnections are referred to in medical treatment as “never events”—a serious event which should never happen and is largely preventable.
The present invention seeks to provide a connector for enteral feeding which serves to couple reliably an enteral feeding solution supply tube to a port of a gastrostomy device. In particular, the connector seeks (for example) to avoid inadvertent misconnection and not appreciably increase wear and tear on internal components of the female button connector.
Viewed from a first aspect the present invention provides a connector for coupling an enteral feeding solution supply tube to a port of a gastrostomy device, wherein the connector comprises: a fluid conduit having an upstream end and a downstream end; a nozzle housing a first portion of the fluid conduit at the downstream end configured to be connectable to an orifice defined in the port of the gastrostomy device, wherein the nozzle has a proximal end, a distal end and a longitudinal axis extending therebetween, wherein an external diameter of the nozzle at or adjacent the distal end is substantially equal to an external diameter of the nozzle at or adjacent the proximal end, and wherein an external surface of the nozzle includes one or more indentations.
In use, the nozzle may be inserted into a respective orifice on the gastrostomy device. The nozzle may be configured to fit snugly (e.g. in a tight friction fit) within the orifice, i.e. the external dimensions of the nozzle may be slightly smaller than the internal dimensions of the orifice. The orifice may be provided with a sealing ring and a non-return valve. The dimensions of the nozzle may be such that when inserted into the orifice, the sealing ring contacts the external surface towards the proximal end and provides a fluid seal. The nozzle also may have a length sufficient for the distal end of the nozzle to push against and fully open the non-return valve when inserted to enable fluid flow. When the nozzle is removed from the orifice, the non-return valve is closed and backflow is prevented.
As the nozzle is pushed into or pulled out of the orifice, the sealing ring may be dragged along the length of the external surface between the distal and proximal ends (during insertion) or vice versa (during removal). Over time and repeated connection/disconnection this contact will cause wear to the sealing ring. The indentations according to the connector of the invention advantageously reduce the surface area of the nozzle which is in contact with the sealing ring and other elastomeric components of the port on the gastrostomy device, thus prolonging the lifetime of these components.
Preferably the nozzle and the respective orifice on the gastrostomy device have a circular cross section. A circular cross-section is advantageous as the connector then need not have a fixed orientation and can rotate within the orifice as required.
The indentations may extend longitudinally for a first distance from a first point at or towards the distal end to a second point between the distal end and the proximal end.
The second point is preferably longitudinally spaced apart from the proximal end by a second distance to define a contact area on the external surface of the nozzle which is substantially free from indentations. This ensures that the sealing ring contacts and provides a fluid seal around the entire circumference of the nozzle when the connector is connected to the port of the gastrostomy device.
Preferably there are multiple indentations spaced apart circumferentially around the external surface and circumferentially separated by ridges (i.e. regions of the external surface which are not indented and which define the outer diameter of the nozzle). The circumferential extent of each indentation may be defined by its arc on an external circumference of the nozzle. There may be any number of indentations, each having the same or a different arc. Preferably the sum of the circumferential extent of each arc is between 50% and 90% of the external circumference of the nozzle. Preferably there are between 2 and four indentations having an equal circumferential extent (arc). Even more preferably there are four equally spaced indentations separated by a total of four ridges, wherein each indentation has a circumferential extent of between 15% and 20% of the external circumference.
The circumferential extent of each ridge may be defined by its arc on an external surface of the nozzle. Preferably the sum of the circumferential extent (arc) of each ridge is between 10% and 50% of the external circumference of the nozzle. Even more preferably the sum of the arc of each ridge is between 20% and 40% of the external circumference of the nozzle. Preferably the arc of each individual ridge is not less than 5% of the external circumference of the nozzle. This ensures that the ridges have sufficient structural rigidity to not deform if a user attempts to force the nozzle into an orifice which is too small.
The first point is preferably at the distal end, such that the indentations extend from the distal end of the nozzle towards the proximal end.
Preferably a first longitudinal distance between the distal end and the second point is greater than a second longitudinal distance between the second point and the proximal end (i.e. the second point is preferably closer to the proximal end than the distal end). Preferably the first longitudinal distance is 1.5 to 3 times longer than the second longitudinal distance. Even more preferably the first longitudinal distance is about 2 times longer than the second longitudinal distance.
The nozzle may have a rounded edge at the distal end to aid insertion into the orifice of the gastrostomy device. Where the distal end has a rounded edge, the rounded edge preferably has a longitudinal extent of less than 5% the length of the nozzle.
The connector may further comprise a body housing a second portion of the fluid conduit at the upstream end, wherein the upstream end of the fluid conduit is configured for connection to an enteral feeding solution supply tube.
The nozzle may have a fillet at the proximal end to increase the structural rigidity of the connection between the nozzle and the body. The fillet preferably has a longitudinal extent of less than 5% of the length of the nozzle.
The external diameter of the nozzle at or adjacent the distal end (i.e. the diameter measured at the distal end where there is no rounded edge, or the diameter of the nozzle adjacent any rounded edge) is substantially the same as the external diameter of the nozzle at or adjacent the proximal end (i.e. the diameter measured at the proximal end where there is no fillet, or the diameter of the nozzle adjacent any fillet). In other words, the nozzle does not have a significant taper between the proximal end and distal end owing to regions such as the contact area and ridges between the indentations which together define the external diameter of the nozzle along its length.
This advantageously means that the nozzle cannot (as it does not have a smaller diameter at the distal end) be inserted or partially inserted (deliberately or accidentally) into an orifice which is smaller than that for which it is designed. The ridges prevent the nozzle being forced into a smaller orifice. This helps to reduce the risk of misconnection errors and “never events”.
Preferably the nozzle has a substantially constant external diameter along its entire length between the proximal and distal ends, excluding any rounded edge or fillet where present.
Preferably an internal diameter of the nozzle (i.e. the diameter of the fluid conduit in the nozzle) is substantially constant along the entire length between the proximal and distal ends.
The second portion of the fluid conduit may be substantially coaxial with the first portion of the fluid conduit. Alternatively the second portion of the fluid conduit may be substantially perpendicular to the first portion of the fluid conduit. This advantageously reduces the risk of the connector being prematurely disconnected if the enteral feeding solution supply pipe is snagged or pulled. The second portion of the fluid conduit may have the same internal diameter as the first portion, or may have a larger or smaller internal diameter. Preferably the second portion has the same or a larger internal diameter than the first portion.
The connector may further comprise an attachment mechanism provided at or adjacent the proximal end of the nozzle to releasably engage with a corresponding element on the gastrostomy device to secure the connector in place during feeding. The attachment mechanism may be provided on the body. The attachment mechanism may include a pair of arms circumferentially arranged around the proximal end of the nozzle, each arm including a first free end and a second free end, wherein the second free end includes a catch configured to releasably engage with a circumferential rim on the port of the gastrostomy device. Each arm may be connected to the body by a flexible bridge about which the first and second free ends of each arm can be pivoted.
The catch may be a ledge located on the inner wall of the arm that projects inwardly towards the nozzle. The ledge may have a rim-contacting surface configured to releasably engage with a ledge-contacting surface of the circumferential rim.
The connector may further comprise a lock member, at least a part of which is configured to be sandwiched between the body and/or proximal end and an inner wall of each arm. The lock member may be removably attached to the connector.
The connector may be moulded as a unitary component from a plastic material such as polyoxymethylene, polyurethane, high density polyethylene, polyvinyl chloride or polypropylene.
Viewed from a second aspect the present invention provides a feeding extension set, comprising: an enteral feeding solution supply tube; and a connector as hereinbefore defined, wherein the connector is configured for coupling the enteral feeding solution supply tube to a port of a gastrostomy device.
Viewed from a third aspect the present invention provides a method of delivering an enteral fluid to a patient comprising the following steps:
A specific implementation of the present invention will now be described, by way of example only, and with reference to the accompanying drawings in which:
Referring initially to
With reference now to
The nozzle 2 has an exterior surface 27. As best shown in
In this embodiment, the longitudinal extent (L) is equivalent to approximately two-thirds of the distance between the distal end 20 and the proximal end 21.
Between the second point 23 and the proximal end 21, the exterior surface 27 is substantially free from indentations. This defines a contact region 25.
With reference now to
The connector 1 is moulded as a unitary component from polyurethane.
With reference now to
The non-return valve 52 in this embodiment is a duckbill valve. A sealing ring 53 extends annularly around the entrance to the port 51. The sealing ring 53 and duckbill valve are composed of an elastomeric material. An outwardly facing rim 54 composed of a rigid plastic material extends circumferentially around the port 51.
The connector 1 is connected to the gastrostomy device 50 by inserting the nozzle 2 into the port 51. As the nozzle 2 is inserted, the distal end 20 contacts and pushes against the duckbill valve 52. The catches 43 on the arms 4 also contact the circumferential rim 54. As shown in
As the connector 1 is pushed further downwards from the position shown in
During insertion of the nozzle 2 into the port 51, the distal end 20 pushes against and opens the duckbill valve 52. The duckbill valve 52 is positioned within the port 51 to prevent accidental opening or damage. The nozzle 2 is long enough to penetrate and fully open the duckbill valve 52.
Once the connector 1 is locked in position on the gastrostomy device 50 and the duckbill valve 52 is open, feed can be supplied via an enteral feeding solution supply tube attached to the upstream end 33 at the shank portion 31 through the fluid conduit 10, the duckbill valve 52, void 55 and into the main channel 61 of the feeding tube 60.
When in the locked position, the sealing ring 53 is in a tight friction fit with the contact region 25, creating a fluid seal to prevent fluid leaking from the port 51. During insertion and removal, the sealing ring 53 is dragged along the exterior surface 27 of the nozzle 2. The indentations 25 (not visible in
Referring now to
As shown in
Number | Date | Country | Kind |
---|---|---|---|
GB2109572.4 | Jul 2021 | GB | national |