WO2002009799A1

WO2002009799A1 - Bougie

Info

Publication number: WO2002009799A1
Application number: PCT/GB2001/003427
Authority: WO
Inventors: David William Green; Stuart Ian Wallace
Original assignee: Individual
Current assignee: Individual
Priority date: 2000-07-31
Filing date: 2001-07-30
Publication date: 2002-02-07
Anticipated expiration: 2003-01-31
Also published as: GB0018743D0; GB0118527D0; GB2368023A; AU2001275723A1

Abstract

The present invention relates to a single use bougie (1) comprising a catheter with a first lumen (3) extending from a proximal end adjacent (2) towards a distal end adjacent end (6) said lumen being provided over at least a major proportion of its length and being provided with an obturated tip adjacent the distal end and at or adjacent its proximal end means to for the connection one or more associated devices, the invention being characterised either by a hollow stiffener (23) insertable within the said first lumen an obturated tip (6) which is exterior so substantially non-traumatising to their pharyngeal, laryngeal or nasal structures, or by a thickened portion substantially in register with the lumen (3) and with the thinner portion substantially in register with the tip portion (4), the arrangement being such that the thicker portion cannot coil up upon itself and wherein the thinner portion is substantially non-traumatic to pharyngeal, laryngeal or nasal structures (17, 18).

Description

BOUGIE

Present invention relates to an improved bougie and to a method of ascertaining its in-use position either in the trachea prior to endotracheal intubation (ETI) or the upper oesophagus prior to upper gastrointestinal tract (GIT) end scopy or gastric

drainage.

Traditional bougies are well known to comprise a solid rod of a. gum elastic material which combines stiffness with flexibility at body temperatures; usually with a smooth distal end angled at about 40° about 3.5cm from the distal tip. When used for ETI a lubricated bougie is directed past the epiglottis and into the larynx and thence into the trachea; usually with the use of a laryngoscope.

However it is often difficult to be sure if the bougie tip has entered the trachea (correct) or the oesophagus (incorrect). With the bougie correctly positioned it is possible for example to 'railroad' an endotracheal tube (ETT) over it through the larynx and into the trachea. The correct position can be confirmed by chest movement (ie inflation via an ETT utilizing a reservoir bag) and the presence of carbon dioxide (CO2) in the expired gas. If the bougie is incorrectly positioned in the oesophagus, the ETI will be 'railroaded' into the oesophagus and no CO2 obtained. In the latter instance, the bougie and ETT must be urgently withdrawn and the process attempted again. As is well known, if the ETT remains in the oesophagus the patient will become hypoxic with serious consequences.

One problem with bougies as currently used lies in the problem of sterilisation. In this connection attention is directed to Anaesthesia 2000, volume 55, pp 466-468. A sterile, single use device for local anaesthesia of the larynx area and referred to as a 'laryng-o-jet' (IMS) is also available. This comprises a tube approximately 20cm long comprising a lumen. This tube is integral with a syringe filled with 4ml of lignocaine at 4% W/V. This device is provided with a hollow tube curved and

obturated at its distal end and provided with a plurality of apertures for the lignocaine. Other anaesthetics can of course be used. The device is introduced into the trachea and the larynx area is treated with lignocaine prior to insertion of the ETT. Since the device is sterile and is adapted for single use only, sterilisation is not required. However, the presence of a fixed syringe at its proximal end and its short length precludes it functioning as a bougie for ETI as described above. US-A-5052836 relates to an endotrachael replacement device which does not require an outer tube which is non-traumatic to nasal structures. W095/11716 relates to an endotrachael tube with a carbon dioxide sensor attached, and

WO 88/06908 relates to an endotrachael tube assembly including an introducer tube but which is genuinely complex.

Another problem lies in that in the prior art devices, the coiling up of nasogastric tubes happens on occasion, along with trauma to delicate structures. Providing a device which does not cause trauma to the delicate nasal or posterior pharyngeal structures is of a positive benefit. This may be achieved by stiffening the tube to allow an easy passage down to the oesophagus to avoid coiling, while also providing a soft tip (6) to the device. The stiffening may be associated with malleability so that the bougie device can be steered by rotation if desired. The present invention provides in one aspect therefore a single use bougie comprising a catheter with a first lumen extending from a proximal toward a distal end, said lumen being provided over at least a major proportion of its length and being provided with an obturated tip adjacent the distal end, and at or adjacent its proximal end means for the connection of one or more associated devices, characterised by a hollow stiffener insertable within the first lumen and by an obturated tip which is exteriorly substantially non-traumatising to nasal structures. In a second aspect there is provided a single use bougie comprising a catheter with a first lumen extending from a proximal to a distal end, said lumen extending over a major proportion of the length of catheter and being provided with an obturated tip adjacent the distal end, and at or adjacent its proximal end means for connection to one or more: devices associated therewith; characterised by a proximal portion substantially in register with the lumen, and with a distal portion substantially in register with a tip portion, the arrangement being such that the proximal portion cannot coil up upon its self, and wherein the distal portion substantially is non- traumatic to nasal or pharyngeal structures.

The bougie of the invention may therefore comprise one or a plurality of apertures connected between the first catheter lumen and the exterior as desired. Other devices maybe used and these include a carbon dioxide (CO2) monitoring device, a syringe device or a cap. The lumen confers on the bougie a non-traumatic resilience which is desirable for its purpose, while the stiffener which may be malleable, provides an elastic memory which allows the bougie to be steered by rotation as desired.

The connection means should be such that it is small enough to fit within an endotracheal intubation tube so that tube can be 'railroaded' down the bougie towards the larynx and trachea or indeed towards the oesophagus if required. A conventional luer-lock arrangement at its proximal end is suitable. By use of this device it is also possible to ascertain if the bougie is correctly orientated in the trachea if used for ETI, or the oesophagus. This is effected by monitoring the CO2 output via the bougie lumen and using a known capnograph (CO2 output monitor), or a device which changes colour in the presence of CO2. It will be appreciated that CO2 is a by-product of respiration and hence is to found in the trachea but not of course in the oesophagus. The bougie of the invention may be made of one or more plastics materials, so long as the softer of materials is to the exterior.

According to a further aspect of the invention therefore there is provided a single use bougie comprising a first catheter with a lumen over at least a major proportion of its length, at least one or a plurality or apertures adjacent the obturated tip, said apertures connecting the lumen with the exterior at its distal end, and at or adjacent its proximal end a CO2 monitoring device.

In another aspect of the invention there is provided a method of determining the position of a bougie tip when in-situ within a patient, said bougie comprising a first catheter lumen extending over a major proportion of its length and an aperture adjacent an obturated tip, connecting said lumen to the exterior, and at or adjacent its proximal end a CO2 monitoring device; comprising the steps, of a) inserting the bougie past the epiglottis b) connecting the proximal tip to a CO2 monitoring device, and, c) monitoring the CO2 output to ascertain if CO2 is present. If CO2 is present the bougie is located within the trachea and if not it is located in the oesophagus. It is also possible using the device of the present invention to 'steer' the bougie tip into the trachea or the oesophagus using the CO2 monitor, particularly if the hollow stiffening member, for example, is formed of nylon or polypropylene which is malleable as discussed above. The bougie of the invention can be used in anaesthetising the larynx, trachea or the oesophagus in ETI or endoscopy.

The device may also be used for operative nasogastric intubation. It is normally placed after endotracheal intubation. It may be inserted via the nasal or oral route. It is not intended that the device is left in-situ for more than a few hours e.g. for use during surgical procedures but not for use in the ward.

The soft tip ensures there is minimal trauma to the delicate nasal and/or posterior pharygeal structures whilst the stiffener which may be made of nylon or polypropylene allows easy passage down the oesophagus and avoids coiling. Thus the exterior tube or catheter may be formed of a soft plastics material for example a medical grade PVC whereas the interior tube may be formed of nylon or polypropylene. Thus insertion is facilitated.

The invention will now be described, by way of illustration only, with reference to the accompanying drawings wherein:- Fig.1 shows in diagrammatic plan a bougie in accordance with the present invention, Fig.2 shows the bougie of the present invention insetted into a patient in part - vertical cross-section,

Fig.2a shows an enlarged view of section of Fig 2 in vertical cross-section,

Fig.3 shows arrangement of Fig 2 utilising an ETI tube, Fig.3a shows an enlarged section of Fig 3 in vertical cross-section,

Fig.4 shows an enlarged vertical cross-section of the device monitoring CO2 expression using the present invention, and Fig.5 shows a diagrammatic plan view of a bougie according to claim 1 with a stiffener internal thereto with the tip (6) of the bougie being other than in the plane of the drawing.

Turning first to Fig.l there is provided a hollow bougie (1) provided with a luer- 5 lock (2) at i ts proximal end, and a lumen (3) extending from the luer-lock (2) to just short of obturated tip (6). The bougie of the invention also provides a curved portion (4) adjacent the obturated tip (6) and a plurality of apertures (5) communicating between the lumen (3) and the exterior. As can be seen from Fig.2a the luer-lock (2) can be associated v/ith a syringe for l o anaesthetic (11) (eg. Lignocaine). Syringe ( 11 ) is secured to the bougie ( 1 ) via the luer-lock (2).

In use (see Fig.3) the patient shown generally at (10), is supine on the operating table with his head upon a pillow (9). A laryngoscope (7) is inserted into the buccal cavity in accordance with usual practice and the bougie ( 1) is positioned

15 with its tip (6) in the larynx (8) in accordance with normal procedures. Using the luer-lock it is possible then to anaesthetise the larynx and trachea as has previously been effected and then to remove the syringe (11) and cap off the lumen (3) by means of a luer-lock cap (not shown). As is shown clearly in Figs.3 and 3a with the larynx suitably anaesthetised it is then

20 possible to intubate with an ETI device which has an interior diameter greater than the exterior diameter of the luer-lock (2). The intubation tube is provided in accordance with traditional methods with a cuff (13) for reasons which are well understood. By means of the invention in Figs.l to 3a it is possible to anaesthetise an appropriate portion to the body and also allow a degree of flexibility/resilience to the bougie thereby to effect in a single device that which was previously been effected by two devices.

In an alternative or additional form of the invention the positioning of the bougie (6) can be closely monitored by using a capnograph (21). As will appreciated a by- product of respiration is carbon dioxide and this can be readily measured. The utilisation of a bougie comprising a lumen allows carbon dioxide to be monitored on a one off or continuous basis. Thus if CO2 levels on the capnograph (21) rise and fall with respiration the tip (6) will be in the trachea whereas if it does not do so the tip (6) will be in the oesophagus. As has been described before it is difficult sometimes for the surgeon to see whether the bougie has entered the trachea or oesophagus even despite the laryngoscope (7) and this will make that clear. Alternatively a CO2 indicating strip may be used to indicate the presence of CO2 above a base value. Turning now particularly to Fig.4 a patient (10) is provided vertical section with a nasal cavity (14) which is essentially left undisturbed. The tip of the bougie (6) is introduced via the buccal opening (15) and into the buccal cavity (16) and then via the posterior pharynx (17) so that the tip (6) then passes the epiglottis (18) and in this particular instance is advanced into the trachea (20). The tip (6) of the bougie (1) may be positioned in the oesophagus in some applications. As the tip of the bougie (6) advances towards the epiglottis ( 18) the luer-lock (2) of the bougie (1) can be connected to a CO2 monitor (21) via a sampling tube (22). As will be appreciated the bougie (1) is provided with a curved portion (4) adjacent its tip (6). This allows the operator to 'steer' the bougie tip (6) merely by rotating the bougie (1). By watching the capnograph (21) it is only necessary that the surgeon ascertain whether CO2 is present or not to ascertain whether the tip of the bougie is in the oesophagus or the trachea.

It will be appreciated that in order to monitor CO2 it may only be necessary to provide a fully continuous lumen within the bougie (1), by removing the obturated tip (6). However if an anaesthetisation is required at the same time, providing a plurality of suitably spaced apertures is most desirable.

With the tip (6) of the bougie (1) in position in the trachea (20) anaesthetic can be dispensed and it is only then necessary to remove the syringe from the luer-lock assembly to 'railroad' the intubation tube (12) over the bougie before withdrawing the bougie.

With reference to Fig.5 there is shown in plan view a stiffened bougie. The bougie of Fig.1 is provided with a stiffener (23) formed for example of nylon 66. This arrangement is both to prevent coiling during use and to reduce the "dead" space for anaesthetic material. The stiffener (23) has an outer diameter of about 3.5mm whereas the outer diameter of a bougie has a value of about .0mm and is formed of medical grade PVC or polypropylene. As can be seen nylon 66 for example has an elastic memory and accordingly is malleable to the extent that an operator can bend it to the desired shape for a particular patient. The invention therefore relates to a sterile bougie according 1o claims 1 or 2 as herein after set forth, to a bougie comprising CO2 monitoring device, and to a method of determining a position of a bougie when in-situ within a patient.

Claims

1. A single use bougie comprising a catheter with a first lumen extending from a proximal toward a distal end, said lumen being provided over at least a major proportion of its length and being provided with an obturated tip adjacent the distal end., and at or adjacent its proximal end means for the connection of one or more associated devices, characterised by a hollow stiffener insertable within the first lumen and by an obturated tip which is exteriorly substantially non-traumatising to pharyngeal, laryngeal or nasal structures.

2. A single use bougie comprising a catheter with a first lumen extending from a proximal to a distal end, said lumen extending over a major proportion of the length of catheter and being provided with an obturated tip adjacent the distal end and at or adjacent its proximal end means for connection to one or more devices associated therewith; characterised by a proximal portion substantially in register with the lumen, and with a distal portion substantially in register with a tip portion, the arrangement being such that the proximal portion cannot coil up upon its self, and wherein the distal portion is substantially non-traumatic to pharyngeal, laryngeal or nasal structures.

3. A bougie according to claim 1 or claim 2 comprising a plurality of apertures adjacent the obturated tip, communicating between the first catheter lumen and the exterior.

4. A bougie according to any preceding claim wherein the other devices secured to the proximal end of the bougie are selected from the CO2 monitoring device, a syringe device or a cap.

5. A bougie according to claim 1 characterised in that the stiffener terminates at its distal end spaced from the obturated tip.

6. A single use bougie comprising a first catheter with a lumen over at least a major proportion of its length, at least one or a plurality of apertures adjacent the obturated tip, said apertures connecting the lumen with the exterior at its distal end, and at or adjacent its proximal end a CO2 monitoring device.

7. A bougie according to any preceding claim characterised in that the hollow stiffener is malleable and the bougie is of a non-traumatising material whereby together they form a malleable tip.

8. A bougie according to claim 7 the catheter is formed of a medical grade PVC material and in that the stiffener is in the form of a medical grade nylon or polypropylene material.

9. A method of determining the position of a bougie tip when in-situ within a patient, said bougie comprising a first catheter lumen extending over a major proportion of its length and an aperture adjacent an obturated tip connecting said lumen to the exterior, and at or adjacent its proximal end a C02 monitoring device; comprising the steps of a) inserting the bougie past the epiglottis b) connecting the proximal tip to a CO2 monitoring device, and, c) monitoring the CO2 output to ascertain if CO2 is present.

10. A method according to claim 9 wherein d) said first lumen further comprises a hollow stiffening member.

11. A method according to either of claims 9 or 10 characterised in that the hollow stiffening member is formed of a malleable material, and that: the first lumen is formed of a material which is non-traumatising to nasal structures.