GB2445655A

GB2445655A - Obturator for laryngeal mask

Info

Publication number: GB2445655A
Application number: GB0725157A
Authority: GB
Inventors: John Edward Nash
Original assignee: Smiths Group PLC
Current assignee: Smiths Group PLC
Priority date: 2007-01-10
Filing date: 2007-12-24
Publication date: 2008-07-16
Anticipated expiration: 2027-12-24
Also published as: GB0700388D0; GB2445655B; GB0725157D0

Abstract

The obturator 2 has a malleable tubular rod 20 with an expansible portion 24 of a foam at its patient end which fills the internal space 30 of the mask portion 14. The compressible nature of the foam 24 enables the obturator 2 to be pulled out of the laryngeal mask 1 after the mask has been inserted in the patient. Locking fitments 12 and 21 on the mask 1 and obturator 2 enable the obturator to be retained with the mask during insertion. Three fins 32 project from the outside of the obturator 2 and centre it towards the patient end of the mask 1.

Description

S

LARYNGEAl MASK ASSEMBLIES AND OBTURATORS This invention relates to laryngeal mask assemblies and obturators.

It is common practice to use an obturator in order to insert an endotracheal tube into a patient. The obturator usually takes the form of a bendable rod inserted along the tube so that the assembly of the tube and obturator can be bent to a preferred shape for insertion. The obturator also serves to block the end of the tube and prevent it catching on anatomical structures during insertion. One example of such an obturator is described in GB2323534. It has also been proposed to use an obturator with a laryngeal mask for the purpose of blocking the end of the airway tube where it enters the internal volume of the mask portion. This serves to prevent the epiglottis entering the end of the airway tube during insertion. An obturator for a laryngeal mask is described in US6050264.

It is an object of the present invention to provide an alternative laryngeal mask assembly and obturator for such an assembly.

According to one aspect of the present invention there is provided a laryngeal mask assembly including a laryngeal mask with a tubular portion and a mask portion mounted at the patient end of the tubular portion such that the tubular portion opens into the interior space of the mask portion, the assembly further including an obturator insertable into and removable from the tubular portion, and the obturator having an expansible portion towards its forward, patient end that expands into the interior space of the mask portion.

The expansible portion of the obturator is preferably arranged substantially to fill the interior space. The expansible portion of the obturator may be provided by a foam, an inflatable cuff or may include a gel. The external diameter of the obturator may be substantially less than the internal diameter of the tubular portion and the obturator may have one or more projections to centre it at least towards the patient end of the tubular portion.

The obturator is preferably malleable or rigid so that it holds the tube to the shape of the obturator while inserted in the tube. The obturator is preferably hollow and opens forwardly of the expansible portion. The obturator and laryngeal mask may be provided with retaining means towards the machine end of the laryngeal mask to hold the obturator in position until it is released. The tubular portion of the laryngeal mask may be flexible and may be reinforced with a helical reinforcement member.

According to another aspect of the present invention there is provided an obturator for an assembly according to the above one aspect of the present invention.

According to a further aspect of the presen invention there is provided a laryngeal mask obturator including a rod portion and an expansible portion towards one end of the rod portion, the expansible portion being arranged substantially to expand to fill an interior space of a mask portion at one end of a laryngeal mask and being collapsible to allow the obturator to be removed from the laryngeal mask.

A laryngeal mask assembly and obturator will now be described by way of example with reference to the accompanying drawing, which is a partly-sectional side elevation view of the assembly with the obturator fully inserted.

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The laryngeal mask assembly comprises a conventional laryngeal mask I and an obturator 2. The obturator 2 is inserted within the laryngeal mask 1 during insertion of the mask in the patient and is subsequently removed.

The mask 1 comprises a curved tubular portion 10 with a machine end 11 having retaining means in the form of a locking fitment 12. The opposite, patient end 13 of the tubular portion 10 supports a mask portion 14 having an integral dished, oval mount 15 to which is attached an inflatable annular sealing cuff 16. The tubular portion 10 and mount 15 are both made of a plastics material and are moulded together as a single piece, such as by injection moulding. Alternatively, the mount and tubular portion could be formed separately and subsequently joined with one another. The tubular portion 10 may be highly flexible, having a thin wall reinforced by a helical reinforcement member (not shown), such as a metal wire or stiff plastics filament.

The obturator 2 takes the form of a tubular rod 20 having an external diameter about half the internal diameter of the tubular portion 10 of the mask 1. The rod 20 is preferably malleable so that it can be bent to a desired shape and then retains this shape. The rod 20 may be made entirely of a malleable material, such as a metal, or it may be made of a plastics material with a malleable insert. Alternatively, the rod 20 could be rigid so that it retains a fixed shape. The rod 20 is substantially the same length as the laryngeal mask I and carries retaining means in the form of a locking fitment 21 fixed at its machine end 22. The locking fitment 21 takes the form of a cylindrical collar adapted to lock with the locking fitment 12 at the machine end 11 of the laryngeal mask 1. The locking fitment 21 on the obturator 2 provides a grip for the user. The locking fitment on the obturator could be extended rearwardly and to one side to provide a handle for use in inserting the assembly.

The locking fitments 12 and 21 limit the extent the obturator 2 can be inserted in the laryngeal mask 1 and, when engaged, lock the obturator and laryngeal mask against inadvertent separation. The tip of the patient end 23 of the obturator 2 is inclined at an angle so that it lies approximately level with the patient end 13 of the laryngeal mask 1 when fully inserted.

The patient end 23 of the obturator 2 has an expansible portion 24 on its outer surface, which in the present embodiment, takes the form of a pear-shape foam member or cushion attached to the outer surface of the obturator 2 and extending along a distance of about 40mm. The narrow end 25 of the foam cushion 24 is to the rear; and the wide end 26 is to the patient end. When located in the laryngeal mask 1, the narrow end 25 of the foam cushion 24 extends a short dislance within the patient end of the tubular portion 10 of the laryngeal mask with the wider, patient end 26 filling substantially the entire internal space 30 or atrium of the mask portion 14. The patient end surface 31 of the foam cushion 24 projects slightly beyond the patient end surface of the mask portion 14 or lies level with it.

The obturator 2 also has three fins 32 (only two being visible) located just rearwardly of the foam cushion 24 and projecting radially outwardly of the obturator equally spaced around its circumference. The fins 32 serve to centre the patient end 23 of the obturator 2 within the tubular portion 10 of the laryngeal mask 1 and their dimensions are such as that their outer edges loosely contact the inner surface of the tubular portion.

The laryngeal mask assembly is used by first inserting the obturator 2 to its full extent into the laryngeal mask 1. Alternatively, the assembly could be provided with the obturator 2 already inserted in the laryngeal mask 1. The foam cushion 24 is compressed during passage along the tubular portion 10 and then expands as it enters the mask portion 14. The locking fitments 12 and 21 are engaged with one another and the assembly is bend to the desired shape for insertion. The assembly is inserted into the patient in the usual way.

The forward surface 31 of the foam cushion 24 ensures that the epiglottis cannot enter the interior space 30 of the mask portion 14 during insertion. It also prevents the tongue being caught on the assembly during insertion. The passage through the obturator 2 allows an endoscope 40 to be inserted via the obturator to confirm correct location. The passage through the obturator 2 also provides an air passage along the assembly when an endoscope is not used. After insertion, the clinician releases the two locking fitments 12 and 21 and pulls the obturator 2 from the laryngeal mask 1 by gripping the locking fitment 21 of the obturator in one hand and the machine end 11 of the laryngeal mask in the other hand. The foam cushion 24 is compressed and collapsed to a smaller diameter by passage along the tubular portion 10 during removal of the obturator. After the obturator 2 has been removed, the laryngeal mask I is used to provide ventilation for the patient in the usual way. The obturator 2 determines the shape of the laryngeal mask 1 during insertion but, after the obturator has been removed, the tubular portion 10 of the laryngeal mask can flex to accommodate movement of the patient in the usual way.

The expansible portion of the obturator need not be provided by a foam cushion but could be of various alternative kinds. For example, it could take the form of an enclosed bag of a gel material that fills the internal space within the mask portion but can be deformed and

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collapsed to allow it to pass along the obturator. Alternatively, the expansible portion could be provided by an inflatable cuff connected via an inflation line to the rear end of the obturator so that the cuff could be inflated, such as with air or a liquid, for insertion of the assembly, and deflated prior to removal of the obturator.

Claims

1. A laryngeal mask assembly including a laryngeal mask with a tubular portion and a mask portion mounted at the patient end of the tubular portion such that the tubular portion opens into the interior space of the mask portion, the assembly further including an obturator insertable into and removable from the tubular portion, wherein the obturator has an expansible portion towards its forward, patient end that expands into the interior space of the mask portion.

2. A laryngeal mask assembly according to Claim 1, wherein the expansible portion of the obturator is arranged substantially to fill the interior space.

3. A laryngeal mask assembly according to Claim I or 2, wherein the expansible portion of the obturator is provided by a foam, an inflatable cuff or a gel.

4. A laryngeal mask assembly according to any one of the preceding claims, wherein the external diameter of the obturator is substantially less than the internal diameter of the tubular portion, and wherein the obturator is provided with one or more projections to centre it at least towards the patient end of the tubular portion.

5. A laryngeal mask assembly according to any one of the preceding claims, wherein the obturator is malleable or rigid such that it holds the tube to the shape of the obturator while inserted in the tube.

6. A laryngeal mask assembly according to any one of the preceding claims, wherein the obturator is hollow and opens forwardly of the expansible portion.

7. A laryngeal mask assembly according to any one of the preceding claims, wherein the obturator and laryngeal mask are provided with retaining means towards the machine end of the laryngeal mask to hold the obturator in position until it is released.

8. A laryngeal mask assembly according to any one of the preceding claims, wherein the tubular portion of the laryngeal mask is flexible.

9. A laryngeal mask assembly according to Claim 8, wherein the tubular portion of the laryngeal mask is reinforced with a helical reinforcement member.

10. A laryngeal mask assembly substantially as hereinbefore described with reference to the accompanying drawings.

11. An obturator for an assembly according to any one of the preceding claims.

12. A laryngeal mask obturator including a rod portion and an expansible portion towards one end of the rod portion, wherein the expansible portion is arranged substantially to expand to fill an interior space of a mask portion at one end of a laryngeal mask and is collapsible to allow the obturator to be removed from the laryngeal mask.

13. A laryngeal mask obturator substantially as hereinbefore described with reference to the accompanying drawings.

14. Any novel and inventive feature or combination of features as hereinbefore described.