Tracheostomy tubes and their manufacture

Abstract

A cuffed tracheostomy tube (1) including a sealing cuff (30) and an inflation line (33), and an uncuffed tube (101) without a sealing cuff both include an identical mounting flange (13) with an aperture (40') within which the rear end of the shaft (10, 110) of the tube is secured. The flange has a passage (45) opening from the aperture (40') and extending through the thickness of the flange. In the cuffed tube the inflation line (33) extends through the passage (45). In the uncuffed tube the passage is blocked by a projection (123) from the shaft.

Description

[0001] TRACHEOSTOMY TUBES AND THEIR MANUFACTURE

[0002] This invention relates to tracheostomy tubes of the kind including a shaft and a mounting flange towards the rear end of the shaft, the mounting flange including an aperture within which the rear end of the shaft is received.

[0003] Tracheal tubes are used to enable ventilation, respiration or spontaneous breathing of a patient. Endotracheal tubes are inserted via the mouth or nose so that one end locates in the trachea and the other end locates outside the patient. Tracheostomy tubes are inserted into the trachea via a surgically formed opening in the neck. Tracheostomy tubes can be inserted by different techniques, such as the surgical cut-down procedure carried out in an operating theatre or a cricothyroidotomy procedure, which may be carried out in emergency situations.

[0004] Tracheostomy tubes are generally used for more long-term ventilation or where it is not possible to insert an airway through the mouth or nose. The patient is often conscious while breathing through a tracheostomy tube, which may be open to atmosphere or connected by tubing to some form of ventilator. The tube is secured in position on the patient's neck by means of a mounting flange fixed with the machine end of the shaft of the tube and positioned to extend outwardly on opposite sides of the tube.

[0005] Tracheostomy tubes can be made of various materials and are usually of a bendable plastics material such as PVC. polyurethane or silicone. Some tracheostomy tubes additionally include sealing means close to their forw ard, distal or patient end. Most commonly, the sealing means is an inflatable cuff attached to the outside of the shaft that is inflated and deflated by a small-bore inflation lumen extending along the shaft to an inflation indicator and valved connector to which the nose of an inflation device such as syringe can be connected. The inflation lumen may be provided in whole or part by a small-bore tube or inflation line that extends through an opening in the mounting flange.

[0006] Tracheostomy tubes need to be made in a range of different sizes to suit different patients and need to be provided in different types, such as. cuffed and uncuffed. and with or without vocalisation fenestrations. The number of different mould tools required to make the entire range of sizes and types leads to high manufacturing costs, both the initial capital costs of the mould tools and the cost of their spares and maintenance. The relatively large number of different components, such as the different shafts and flanges, means that large component inventories are needed, leading to high costs, waste and supply chain complications.

[0007] It is an object of the present invention to provide an alternative tracheostomy tube, set of tubes and a manufacturing method.

[0008] According to one aspect of the present invention there is provided a tracheostomy tube of the above-specified kind, characterised in that the aperture opens into a passage at one side that extends through the thickness of the flange, and that the passage is capable both of receiving an inflation line where the shaft is provided with an inflatable sealing cuff and alternatively receiving a radial projection from the rear end of the shaft that blocks the passage where the shaft is not provided with an inflatable sealing cuff.

[0009] The shaft preferably has an external boss towards its rear end, the boss being adapted to be received in the aperture in the mounting flange. The aperture through the mounting flange is preferably formed with a rearwardly -facing step arranged to abut a forwardly- facing wall on the boss of the shaft. The aperture may include two recesses spaced from one another around the aperture, one of the recesses including the passage that extends through the thickness of the flange, and the other recess being adapted to receive an outwardly- projecting lug on the shaft. The shaft and mounting flange are preferably of a silicone material.

[0010] According to another aspect of the present invention there is provided a set of a cuffed and an uncuffed tracheostomy tube both including a shaft and a mounting flange, the mounting flange of both tubes being of the same kind provided with an aperture within which the rear end of the respective shaft is received, the aperture opening into a passage at one side that extends through the thickness of the flange, the shaft of the cuffed tube including an inflatable sealing cuff mounted towards its patient end, an inflation line communicating at one end with the interior of the sealing cuff and extending through the passage through the flange, and the shaft of the uncuffed tube being without a sealing cuff or inflation line and having an outward projection towards its rear end that locates with the passage through the flange to block the passage.

[0011] According to a further aspect of the present invention there is provided a method of manufacture of a tracheostomy tube including the steps of providing a shaft selected from a cuffed shaft with an inflation line communicating at one end with the interior of a sealing cuff and an uncuffed shaft without an inflation line and having a radially outwards extending projection towards its rear end, providing a common mounting flange including an aperture opening into a passage at one side that extends through the thickness of the flange, and joining the cuffed or uncuffed shaft with the aperture in the flange, in the case of the cuffed shaft, so that the inflation line extends through the passage in the flange and, in the case of the uncuffed shaft, so that the projection locates with the passage through the flange and blocks the passage.

[0012] According to yet another aspect of the present invention there is provided a cuffed tracheostomy tube made by a method according to the above further aspect of the present invention.

[0013] According to a fifth aspect of the present invention there is provided an uncuffed tracheostomy tube made by a method according to the above aspect of the present invention.

[0014] A set of a cuffed and uncuffed tracheostomy tube and their methods of manufacture according to the present invention will now be described, by way of example, with reference to the accompanying drawings in which:

[0015] Figure 1 is a perspective view of the machine end of the cuffed tube of the set from its patient side;

[0016] Figure 2 is a perspective view of the machine end of the tube shown in Figure 1 from its machine side with the inflation line omitted for clarity; Figure 3 is a perspective view of the machine end of the uncuffed tube of the set from its patient side;

[0017] Figure 4 is a perspective view of the machine end of the tube shown in Figure 3 from its machine side;

[0018] Figure 5 is a perspective view of the mounting flange without a shaft;

[0019] Figure 6 is a perspective view of the machine end of the shaft for a cuffed tube, with the inflation line omitted for clarity; and

[0020] Figure 7 is a perspective view of the machine end of the shaft for an uncuffed tube.

[0021] With reference first to Figures 1, 2 and 6 the cuffed tracheostomy tube 1 has a curved shaft 10 of circular section moulded from a flexible plastics such as silicone. The patient, distal or forward end 11 of the tube 1 is adapted to locate in the trachea. The machine, proximal or rearward end 12 of the tube 1 extends through the tracheostomy and opens externally of the patient. The machine end 12 of the tube supports a laterally extending mounting flange 13 adapted to lie against the skin of the neck and having openings 14 at opposite ends that receive ends of a neck tie (not shown) extending around the neck. The machine end 12 of the tube 1 also includes an externally tapered 15mm male connector 15 arranged to receive a cooperating female connector (not shown) at one end of ventilation tubing. The connector 15 illustrated is a separate component from the shaft 10. It is moulded from a harder plastics than that of the shaft and is subsequently attached inside the rear end of the shaft. Alternatively, the connector could be an integral component, one piece with the shaft. Where the patient is breathing spontaneously a connector might not be needed so the shaft could be terminated by a low-profile end fitting.

[0022] The rear end of the shaft 10 is terminated by an external circular boss 16 (most clearly seen in Figure 6) comprising a forward circular inner step 17 and a rear outer step 19, thereby forming two forwardly-facing annular walls 20 and 21. The boss 16 is circular around its entire circumference apart from two, diametrically opposite tapered outwardly- projecting radial lugs or projections 22 and 23 on the rear step 19. One lug 22 is plain and the other lug 23 is formed on its forward surface with a recessed channel 24 aligned with an axial channel 25 in the forward step 17 the purpose of which will be explained later.

[0023] The tube 1 also includes sealing means in the form of an inflatable sealing cuff 30 such as of the low-volume / high-pressure ty pe in the form of an elastic silicone sleeve attached by opposite end collars 31 to the outside of the shaft 10 close to its patient end 11. The cuff 30 overlies the patient end opening 31 of an inflation lumen 32 on the outside of the shaft 10 so that the cuff can be inflated by supplying fluid (such as saline or air) to its interior via the lumen and its opening. The inflation lumen 32 extends along a plane parallel to and spaced from the plane of curvature of the shaft 10 by a distance equal to the external radius of the shaft. The inflation lumen 32 is provided by a small-bore inflation line or tube 33 secured along the outside of the shaft 10 as far as the boss 16 and in line with the channels 25 and 24 on the lug 23.

[0024] With reference now also to Figure 5, the flange 13 is a separately made component and may be moulded from a soft material such as silicone. The flange 13 has an integral, enlarged central collar 40 with a central circular aperture 40’ shaped to receive the boss 16 at the rear end of the shaft 10. The interior of the collar 40 is formed with a short, forward portion 41 of reduced diameter so as to provide a rearwardly facing step 42 to abut the face 21 on the rear step 19 on the boss 16. The rear part 41 ’ of the interior of the collar 40 is formed with two diametrically opposite recesses 43 and 44, which taper externally to a smaller width. The recesses 43 and 44 are arranged along a diameter of the collar 40 extending along the longitudinal axis of the flange 13, which lies orthogonally of the plane of curvature of the shaft 10. The recesses 43 and 44 are positioned and shaped to receive the lugs 22 and 23 on the shaft 10. One of these recesses 44 opens externally through the thickness of the collar 40 to form a slot or passage 45 through the flange 13. This continues internally as a short ramp surface 46 on the step 42 in alignment with the passage 45.

[0025] The tube 1 is manufactured by first separately moulding the mounting flange 13 and a sub-assembly of the shaft 10 with the sealing cuff 30, inflation line 33 and connector 15. The subassembly is threaded through the aperture 40’ in the flange 13 from its patient end 1 1 with the lugs 22 and 23 aligned with the recesses 43 and 44. When fully inserted the face 21 on the step 19 of the boss 16 contacts the step 42 in the collar 40. At the same time, the loose part of the inflation line 33 is laid onto the channels 24 and 25 on the lug 23 of the boss 16. As the lugs 22 and 23 slide into the recesses 43 and 44 the inflation line 33 is pushed along the passage 45 in the collar 40. A solvent, adhesive or the like is applied to the outside of the boss 16 or the inside of the collar 40 before assembly, or both, so that the two components are secured together after curing and the inflation line 33 is bonded in place where it emerges through the passage from the collar 40 between the lug 23 and the forward end of the slot 45. Engagement of the lugs 22 and 23 in the recesses 43 and 44 ensures the correct orientation of the mounting flange 13 relative to the curve of the shaft 10. The different shapes of the two lugs 22 and 23 make it easier for manufacturing operators to ensure that the mounting flange 13 is correctly loaded on the shaft 10, thereby reducing loading errors and handling time and improving yields. The rear end of the inflation line 33 could be joined with a combined inflation indicator and valved connector 50 either before or after assembling the shaft 10 with the flange 13.

[0026] The other member of the set of tubes is an uncuffed tube 101 as show n in Figures 3, 4 and 7. The uncuffed tube 101 is very similar to the cuffed tube 1 and, in particular, its mounting flange 13 is identical with that 13 in the cuffed tube. The uncuffed tube 101 differs from the cuffed tube 1 by having a shaft 110 without any sealing cuff or inflation line. The boss 116 of the uncuffed tube 101 is also slightly different in that the projection or lug 123, which in the cuffed tube 1 leaves a passage between it and the passage 25 through the mounting flange 13, is shown to fill and block the slot 125 in the collar 140 to avoid any passage or cavity that could otherwise trap contamination. This arrangement differs from previous tracheostomy tubes of the kind having a mounting flange formed separately of the shaft w here the mounting flanges on cuffed and uncuffed tubes differ from one another to match the different features of the respective shafts. The lugs 122 and 123 on the uncuffed tube 101 serve the same locating purpose as with the cuffed tube 1 of ensuring that the mounting flange 13 is correctly oriented with respect to the curvature of the shaft 110. In this arrangement the passage through the flange is capable both of receiving an inflation line, where the shaft has an inflatable sealing cuff, and alternatively receiving a radial projection from the rear end of the shaft that blocks the passage, where the shaft does not have an inflatable sealing cuff. The arrangement, therefore, avoids the need for different mounting flanges for the cuffed and uncuffed tubes, thereby reducing the number of moulds needed and hence the capital and maintenance cost of the mould tooling. It also enables inventory' to be reduced since there is no need to maintain separate stocks of different mounting flanges to meet demand for cuffed or uncuffed tubes.

Claims

CLAIMS1. A tracheostomy tube (1, 101) including a shaft (10, 110) and a mounting flange (13) towards the rear end (12) of the shaft, the mounting flange including an aperture (40') within which the rear end of the shaft is received, characterised in that the aperture (40’) opens into a passage (45) at one side that extends through the thickness of the flange, and that the passage is capable both of receiving an inflation line (33) where the shaft (10) is provided with an inflatable sealing cuff (30) and alternatively receiving a radial projection (123) from the rear end of the shaft (110) that blocks the passage where the shaft is not provided with an inflatable sealing cuff.

2. A tracheostomy tube according to Claim 1, characterised in that the shaft (10, 110) has an external boss (16) towards its rear end, and that the boss (16) is adapted to be received in the aperture (40’) in the mounting flange (13, 113).

3. A tracheostomy tube according to Claim 2, characterised in that the aperture (40’) through the mounting flange (13) is formed with a rearwardly -facing step (42) arranged to abut a forwardly -facing wall (21) on the boss (16) of the shaft.

4. A tracheostomy tube according to any one of the preceding claims, characterised in that the aperture (40’) includes two recesses (43 and 44) spaced from one another around the aperture, that one of the recesses (44) includes the passage (45) that extends through the thickness of the flange, and that the other recess (43) is adapted to receive an outwardly-projecting lug (22, 122) on the shaft.

5. A tracheostomy tube according to any one of the preceding claims, characterised in that the shaft 10, 101) and mounting flange (13) are of a silicone material.

6. A set of a cuffed and an uncuffed tracheostomy tube (1, 101) both including a shaft (10, 110) and a mounting flange (13), characterised in that the mounting flange of both tubes is of the same kind provided with an aperture (40’) within which the rear end of the respective shaft is received, that the aperture opens into a passage (45) at one side that extends through the thickness of the flange, that the shaft (10) of thecuffed tube includes an inflatable sealing cuff (30) mounted towards its patient end, that an inflation line (33) communicates at one end with the interior of the sealing cuff and extends through the passage through the flange, and that the shaft (110) of the uncuffed tube is without a sealing cuff or inflation line and has an outward projection (123) towards its rear end that locates with the passage (45) through the flange (13) to block the passage.

7. A method of manufacture of a tracheostomy tube including the steps of providing a shaft selected from a cuffed shaft (10) with an inflation line (33) communicating at one end with the interior of a sealing cuff (30) and an uncuffed shaft (1 10) without an inflation line and having a radially outwards extending projection (123) towards its rear end, providing a common mounting flange (13) including an aperture (40‘) opening into a passage (45) at one side that extends through the thickness of the flange, and joining the cuffed or uncuffed shaft with the aperture in the flange, in the case of the cuffed shaft, so that the inflation line (33) extends through the passage (45) in the flange (13) and, in the case of the uncuffed shaft, so that the projection (123) locates with the passage (45) through the flange and blocks the passage.

8. A cuffed tracheostomy tube (1) made by a method according to Claim 7.

9. An uncuffed tracheostomy tube (101) made by a method according to Claim 7.

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