GB2354948A

GB2354948A - Laryngoscope blade

Info

Publication number: GB2354948A
Application number: GB9918452A
Authority: GB
Inventors: Peter William King-Lewis; Mike Craig Harrison
Original assignee: KING LEWIS PETER WILLIAM
Current assignee: KING LEWIS PETER WILLIAM
Priority date: 1999-08-06
Filing date: 1999-08-06
Publication date: 2001-04-11
Also published as: WO2001010293A1; GB9918452D0; AU6305900A

Abstract

A laryngoscope blade comprises a body portion 10 for insertion, the body portion comprising an elongate neck 12 in which is formed a channel 18 to assist in the guiding of tubes during intubation, the channel being defined by at least a lower wall, a side wall 20 and a top wall 22, the minimum thickness of the lower wall being not less than 80% of the internal distance between the top wall and the lower wall. The top wall extends over between 40% and 70% of the width of the bottom wall to balance protection provided for the soft tissues of the neonate with reduction of the bulk of the blade in the confines of the neonate throat. In a further aspect, a laryngoscope blade comprises a body portion for insertion comprising an elongate neck in which is formed a channel to assist in the guiding of tubes during intubation, and a socket portion 17 for attachment to a laryngoscope handle, the socket comprising an extended hook portion 26 for engaging with the handle and a sidewardly extending protrusion 30 which is depressable into the socket but biassed to protrude.

Description

2354948 1 LARYNGOSCOPE BLADE The present invention results to a

laryngoscope blade.

In our earlier Application GB 2296436, we described a novel laryngoscope blade which was particularly suitable for the examination of neonates and was adapted to conduct light through the body of the blade.

The design described in GB 2296436 provided the first purposedesigned laryngoscope blade for the examination of neonates. Prior to that blade, neonatal laryngoscopes were essentially scaled down versions of laryngoscopes used for older children and adults. Such blades caused considerable practical difficulties as set out in our earlier Application.

Further investigation of our blade has revealed that, whilst offering a significant advance, its suitability for part of the population of neonates could be improved.

The present invention therefore provided a laryngoscope blade comprising a body portion for insertion, the body portion comprising an elongate neck in which is formed a channel to assist in the guiding of tubes during intubation, the channel being defined by at least a lower wall, a side 2 wall and a top wall, the minimum thickness of the lower wall being not less than 80% of the internal distance between the top wall and the lower wall.

Given that the thickness of the channel will usually be adapted to suit the thickness of an intubation tube, this essentially places constraints on the total thickness of the body portion of the blade which therefore renders it particularly suitable for most neonates.

Preferably, the aspect ratio of the insertable length of the blade is greater than 2.5:1. This again places constraints of the total thickness of the blade whilst providing for an adequately long insertable length.

The top wall preferably extends over at least 40% of the insertable blade length. This then permits protection of the soft tissues of the neonate from the tip of the tube as it is inserted.

It is also preferable that the top wall extends over at least 40 % of the width of the bottom wall. If the top wall extends over a lesser distance then less protection is provided to the soft tissues of the neonate. However, it is preferred that the top wall extends over less than 70% of the width, as a greater proportion will tend to increase the bulk of the blade which is undesirable in the confines of the neonate throat.

The invention also provides, in a further and independent aspect, a laryngoscope blade comprising a body portion for insertion comprising an elongate neck in which is formed a channel to assist in the guiding of tubes during intubation, and a socket portion for attachment to a laryngoscope handle, the blade being fabricated of a transparent, lightconveying plastics 3 material, the socket comprising an extended hook portion for engaging with the handle and a sidewardly extending protrusion which is depressable into the socket but biassed to protrude, also to engage with the handle.

The protrusion is preferable a metallic member biassed by a spring located within a blind bore in the socket. The metallic member is preferably substantially spherical.

An embodiment of the present invention will now be described by way of example, with reference to the accompanying Figures, in which; Figure 1 is a side view of the laryngoscope blade according to the present invention; Figure 2 is a section of the laryngoscope blade according to the present invention on 11-11 of figure 1; and Figure 3 is an end view of the laryngoscope blade according to the present invention, in the direction of arrow III of figure 1.

Figure 1 shows the blade from the side. The body portion 10 includes an elongate neck 12 which is intended for insertion through the bucal cavity into the pharynx and thus into the trachea of a neonate. It is formed of polycarbonate or acylic and edges are rounded as shown (for example) at 14 to limit damage to internal tissues of the patient. The tip 16 of the neck is deflected downwardly to assist in navigating the blade around curved passages. A socket 17 extends downwardly from the body and, as will be described later, allows the blade to be attached to a known handle (not 4 shown) of conventional design.

A channel 18 is defined in the neck by a side wall 20 which extends upwardly from the main part of the neck 12, and a top wall 22 which returns over the main part from the upper extent of the side wall 20. The channel opens at the root 24 of the neck. A tube can thus be introduced into the trachea after insertion of the blade by passing it through the channel 20, assisted initially by the widening at 24.

The main part of the neck 12 is about 4Y2mm thick, and the channel is about 5mm deep. The top wall 22 is about 2mm thick, giving a total thickness of about 11 Y2mm for the neck. This has been found to be capable of being accommodated by a neonate. By making the channel and the main part of comparable depth, a sufficiently deep channel for a tube can be combined with a neck which is strong enough to withstand normal use.

The usable part of the neck 12, ie that part which can be inserted, is about50mmlong. This is the length from the tip of the neck 22 tothe front face of the socket 17, which will in use approach the chin of the patient and will not be inserted. This length allow the blade to penetrate deeply enough to guide the tube to an adequately deep location without the tube having to pass unprotected along a significant length of the patient's throat. As the tip of the tube may be cut and hence relatively sharp, this is of significant benefit to the neonatal patient. Thus, the neck 12 has an aspect ratio of about 4:1, which combines adequate length without excessive thickness.

The top wall 22 extends over about 30mm of the insertable length of neck 12. This serves to protect the throat tissue of the patient from the tube, as noted above. This length is therefore about 60% of the insertable length of the neck 12.

As can be seen in figures 2 and 3, the top wall 22 extends only partly over the main part of the neck 12 when seen from one end. This is because this is in practice all that is needed to prevent a tube from contacting the throat tissue. By narrowing the top wall 22, the overall profile of the blade is reduced, allowing insertion into tighter passages of smaller neonates. In the embodiment shown, the top wall 22 is about 7mm wide in total, whilst the neck 12 is about 1 3mm wide in total. Thus, the top wall covers about 40% of the neck 12.

The socket 17 of the blade 10 comprises a hook 26 defined by a recess 28 formed across the width of the socket 17, and a protrusion 30. The hook 26 engages with a handle (not shown) beneath a retaining rod which is provided thereon. The protrusion 30 is a ball bearing seated within a blind bore 32 in the socket 17. A compression spring 34 is seated in the bore 32 to bias the ball bearing 30 outwardly. To prevent release of the ball bearing 30, the bore 32 has a slightly narrower throat. The bore 32 can be lined with a metallic member to add strength. In a preferred arrangement, the plastics socket 17 is provided with a through bore in which is placed a n externally threaded metallic part which defines the blind bore 32. A hollow screw is then inserted from the other side of the through bore and engage with the thread of the metallic part and hold it firmly within the socket 17.

It will be appreciated by those skilled in the art that many variations can be made to the above-described embodiment without departing from the present invention.

6

Claims

1 A laryngoscope blade comprising a body portion for insertion, the body portion comprising an elongate neck in which is formed a channel to assist in the guiding of tubes during intubation, the channel being defined by at least a lower wall, a side wall and a top wall, the minimum thickness of the lower wall being not less than 80% of the internal distance between the top wall and the lower wall.

2. A laryngoscope blade according to claim 1 in which the aspect ratio of the insertable length of the blade is greater than 2.5:1.

3. A laryngoscope blade according to claim 1 or claim 2 in which the top wall extends over at least 40% of the insertable blade length.

4. A laryngoscope blade according to any preceding claim in which the top wall extends over at least 40% of the width of the bottom wall.

5. A laryngoscope blade according to any preceding claim in which the top wall extends over less than 70% of the width.

6. A laryngoscope blade comprising a body portion for insertion, which comprises an elongate neck in which is formed a channel to assist in the guiding of tubes during intubation, and a socket portion for attachment to a laryngoscope handle, the blade being fabricated of a transparent, light-conveying plastics material, the socket comprising an extended hook portion for engaging with the handle and a sidewardly extending protrusion which is depressable into the socket but biassed to protrude, also to engage with the handle.

7 7. A laryngoscope blade according to claim 6 in which the protrusion is a metallic member biassed by a spring located within a blind bore in the socket.

8. A laryngoscope blade according to claim 7 in which the metallic member is substantially spherical.

9. A laryngoscope blade substantially as herein described with reference to and/or as illustrated in the accompanying figures.