CURVED BOUGIE LEAD

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to, and the benefit of, U.S. provisional patent application serial number 62 / 872,848 filed on July 11, 2019.BACKGROUND1. Technical Field

[0002] The technology of this disclosure pertains generally to patient endotracheal intubation assistance devices, and more particularly to patient endotracheal intubation via guided delivery of a bougie.2. Background Discussion

[0003] Clinicians (primarily anesthesiologists, intensivists, and emergency medicine physicians) have long used direct laryngoscopy to visualize the glottis (opening to the trachea that includes the vocal cords) in order to perform endotracheal intubation. This procedure requires much practice, is challenging to perform, and in some patients can be impossible even in expert hands. Rarely, the consequences of failure can include brain damage and death. Over the years numerous techniques have been developed to improve our odds of success, but no technique or combination of techniques has proven 100% reliable, even in patients with apparently normal airway anatomy. One such technique that has recently become widely available is video laryngoscopy. With this technique the odds of successfully visualizing the glottis approach 100%. However, visualization does not guarantee successful endotracheal intubation.

[0004] Guiding the endotracheal tube into the glottis can be challenging even when visualization is excellent. The most reliable video laryngoscope blades (the part of the instrument that pushes the tongue anteriorly and out of the line of vision) are hyperangulated. At times the angle of approach to the glottis is so anterior that the endotracheal tube tip, even when a stylet (a thick, stiff wire placed inside the endotracheal tube) designed to match the "hyper" angle of the blade is used, the tube cannot be slipped beyond the vocal cords.

[0005] A soft, non-malleable device called a bougie is sometimes used to aid guidance of the endotracheal tube into the trachea. While a bougie may have numerous uses in medicine, they are typically used to widen a passageway or guide another instrument into a passageway. The bougie is somewhat easier to pass between the vocal cords since it is smaller and easier to manipulate than the endotracheal tube. However, it is likely to be ineffective during video laryngoscopy since it is not stiff enough to hold a curved shape. A stiffer, malleable bougie exists but passing it into the trachea risks potentially fatal injury to the trachea or deeper airways.

[0006] US2012 / 298112 discloses an endotracheal tube having more than six degrees of freedom. The tube includes a first element having a distal end portion which is capable of achieving a curved configuration and a second element having a distal end portion which is capable of achieving a curved configuration. The first and second elements are rotationally and translationally connected to each other. The structure may also be used as a stylet for an endotracheal tube.

[0007] WO00 / 18461 discloses an oral airway (510) that includes an elongate tubular member (512) having a distal (510) and a proximal end (514) with an enlarged wedge-shaped housing (520) at the distal end. The wedge-shaped housing (520) is for insertion into the mouth (1) and pharynx (7A) of a patient with the proximal end of the tubular member extending from the mouth of the patient. The wedge-shaped housing (520) has anterior (522) and posterior (524) walls forming an enlarged proximal portion (520) tapering to a smaller distal portion (532) with a leading opening (534) separating the anterior (522) and posterior (524) walls at the distal end of the housing. A grate (537) covers the leading opening. Sidewalls (526, 528) extend between the anterior (522) and posterior (524) walls and the wedge-shaped housing (520) is configured so that the sidewalls abut the ary epiglottic folds (576) as the wedge-shaped housing is inserted into the hypopharynx (7) of a patient to arrest insertion of the wedge-shaped housing and seat the wedge-shaped housing with the leading opening (534) adjacent to the glottis (9).

[0008] US6,874,504 discloses an endotracheal tube that includes a proximal tube shaft and a distal tube shaft coupled to the proximal tube shaft. The proximal tube shape defines a proximal lumen and the distal tube shaft defines a distal lumen extending from the proximal lumen. The distal tube shaft includes two or more curved portions configured to be inserted into the trachea when the tube is inserted into a patient. The proximal tube shaft includes a substantially straight or a slightly curved portion. A method of intubating a patient includes advancing a tube having a distal portion with at least two curved portions into the trachea of the patient, and delivering gas through the tube to the patient's lungs.

[0009] WO 2019 / 222196 discloses embodiments directed to a bougie device and methods of use thereof, the device directing the deployment of an endotracheal tube through the larynx.BRIEF SUMMARY

[0010] The invention is defined by the enclosed claims. An aspect of the present description is a guide apparatus, system and method for endotracheal intubation using a pre-shaped, curvilinear guide to deliver a flexible (atraumatic) bougie into the trachea under videoscopic visualization. The guide serves as a conduit through which the bougie is passed. The system and method is proven easy, quick and effective. The technique is intuitive and needs little to no special training for anyone proficient in the use of video laryngoscopy for endotracheal intubation.

[0011] Further aspects of the technology described herein will be brought out in the following portions of the specification, wherein the detailed description is for the purpose of fully disclosing preferred embodiments of the technology without placing limitations thereon.BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S)

[0012] The technology described herein will be more fully understood by reference to the following drawings which are for illustrative purposes only: FIG. 1 shows a schematic side view of a bougie guide in accordance with the present description installed into the trachea of a patient along with a video laryngoscope blade. FIG. 2 shows a side view of the bougie guide of FIG. 1. FIG. 3 shows a front view of the bougie guide of FIG. 1. FIG. 4 is a schematic side-section view of the bougie guide of FIG. 1 with a distal end of a bougie being delivered into the trachea. FIG. 5 is a side view of the bougie guide of FIG. 1 removed to leave the distal end of a bougie at the desired location in the trachea. DETAILED DESCRIPTION

[0013] FIG. 1 through FIG. 5 illustrate embodiments of a guide apparatus, system and method for endotracheal intubation using a pre-shaped, curvilinear guide to deliver a flexible (atraumatic) bougie into the trachea under videoscopic visualization.

[0014] Referring to FIG. 1, an embodiment of a bougie guide apparatus 10 in accordance with the present description is shown installed in glottis 36 for access of the trachea 34 after placement of a video laryngoscope blade 30. The video laryngoscope blade 30 acts to push the tongue 38 anteriorly and out of the line of vision, and the distal tip of the blade 30 is configured to curve around the tongue 38 to the epiglottis 32. The distal end of the blade 30 comprises a camera 40 for visualization of the patient anatomy and glottis 36.

[0015] In the embodiment shown the bougie guide 10 comprises an elongate tube 12 having a collar 14 at its proximal end, with the tube 12 having a tapered, curved shape terminating at distal end 22. The tube 12 comprises a central aperture 16 the extends from the collar 14 at the proximal end to the distal end 22 for passage of a bougie.

[0016] The tube 14 comprises a primary or first curvature 18 that is sized and angled to follow path of blade 30 at least partially along its length. However, as shown in FIG. 1, the orientation of the blade 30 with respect to the glottis 36 and trachea is hyperangulated with respect to the glottis 36 and trachea 34, such that the angle of approach of a tube merely matching its path would place and / or orient the bougie too far anterior within the patient, thus creating problems for the bougie and endotracheal tube to be positioned beyond the vocal cords and glottis 36.

[0017] To accommodate these anatomical difficulties, the tube 12 comprises a second curvature 20 that is distal to first curvature 18. The second curvature 20 reverses course of the first curvature 18 to form a subtle "s" shape that positions and orients the distal end 22 of the guide 10 at the glottis 36, preferably at an angle substantially aligned with path of the trachea 34.

[0018] FIG. 2 and FIG. 3 show side and front views, respectively, of the bougie guide 10 in detail. Elongate tube 12 comprises a circular cross-section that tapers from the proximal end, with an internal diameter D I that is larger than the diameter D I2 at the distal end 22. In one embodiment, internal diameter D I of central aperture 16 is approximately 15mm at the collar 14, and the internal diameter D I2 is approximately 7mm.

[0019] In the embodiment shown in FIG. 2 the tube 12 has a straight section that slopes slightly from the collar 14, and leads into first curvature 18 having a radius r 1 that is generally larger than second curvature 20 having radius r 2 . The curvature leading through r 1 is generally configured to follow the natural curvature of the tongue 38, (approximately 95° to 105°). While curvatures 18 and 20 are shown having a radius, it is appreciated that curvatures 18 and 20 may comprise any curvilinear shape or path.

[0020] The collar 14 is generally circular in shape, having a thickness t of approximately 3 mm, and diameter D 2 of approximately 25mm. The collar 14 has a thumb notch 15 to help with administering and / or rotating the guide 10, and as well providing a tactile (and visual) indicator or clocking of the rotational position of the guide 10 in the patient.

[0021] In one embodiment the overall length L of the guide 10 is approximately 130 mm, and the height h is approximately 60mm.

[0022] It is appreciated that all dimensions are provided for illustrative purposes only, and that sizing and variations in orientation and shape may be employed to match certain patients (e.g. a bougie guide 10 may have smaller dimensions for small patients / children).

[0023] The overall length L of the guide 10 is sized so that the distal end 22 can extend to or past the glottis 36 while the collar 14 at the proximal end is external to the patient's mouth to allow for ease of manipulation from outside the mouth and optimal positioning options. The round profile of tube 12, along with notch 15 in collar 14, allow for easy rotation within the oropharynx when guiding the distal end 22 of tube 12 to the target location. The wall thickness of the tube 12 is generally about 1mm to 3mm, with sufficient material for rigidity to maintain its preformed curvature, while also being slightly compliant to deflect when necessary.

[0024] In a preferred embodiment, the tube 12 is constructed from a non-reflective dark-colored plastic that minimizes videoscopic glare. While any number of materials may be selected, the tube 12 is comprised of a generally semi-rigid to rigid material or construction to hold its shape, with inner and outer surfaces having a "slippery" or low-friction texture configured to easily glide into the oropharynx and with respect to the bougie without resistance. A biocompatible coating may be applied to inner and outer surfaces of tube 12 to minimize friction between anatomy and components. In a preferred configuration the guide 10 is single use.

[0025] A preferred method for endotracheal intubation using the pre-shaped, curvilinear bougie guide 10 of the present description is detailed in FIG. 1, FIG. 4 and FIG. 5.

[0026] As seen in FIG. 1, a video laryngoscope blade 30 is inserted into the patient's mouth and advanced such that the distal tip of the blade 30 curves around the tongue 38 and lodges anterior to the epiglottis 32. This acts to push the tongue 38 anteriorly and out of the line of vision. Visualization of the oropharynx is achieved with camera 40.

[0027] Next, the distal end 12 of the bougie guide 10 is inserted in the patient's mouth and manually advanced through the oropharynx along the path of the blade 30. The collar 14 and thumb notch 15 provide manual purchase at the proximal end of the guide 10 for both translation and rotation of the tube 12 when guiding the distal end 22 of tube to the target location. Slight clockwise or counterclockwise rotation of the tube 12 can affect the curvature of the tube in the mouth, as well as position and orientation if the distal end 22 of the tube 12 to advance past tight anatomy, preferably with aid of videoscopic visualization via camera 40. The flat of the thumb notch 15 also serves as a rotational reference point for the physician while installing the guide 10.

[0028] FIG. 4 is a schematic side-section view of the bougie guide 10 with a distal end 52 of a bougie 50 being delivered into the trachea 34. The bougie 50 is preferably sized with sufficient length, diameter and flexibility to navigate through the length of the tube 12. One exemplary bougie configuration is 15 Fr × 70 cm with Coude tip (e.g. model 9-0212-70 by SunMed (www.sun-med.com). With the distal end 22 of the guide 10 installed at the target location at the glottis 36, the flexible (atraumatic) bougie 50 is inserted in aperture 16 at the proximal collar 14 and advanced along the length of the tube 12. The taper of the tube 12 with the larger diameter at the proximal end 14 allows for easy advancement through the mouth, (promoting for less friction where the anatomy is more "open") and then constricts to a smaller diameter when the anatomy becomes more tight, while still having an inner diameter D I2 to allow for sufficient passage of the bougie 50.

[0029] When the distal end 52 of a bougie 50 reaches distal end 22 of the guide 10, it is positioned at the glottis 36 and lined up with the trachea 34 (as a result of the curvatures 18 / 20 in the tube 12) so that it easily passes through vocal folds of the glottis 36 and into the trachea 34. Placement of the distal end 52 may be verified under videoscopic visualization.

[0030] In addition to or as alternative to visualization, the bougie 50 may comprise a series of bands or markers 54 corresponding to the length along the aperture 16 of the guide tube 12, which provides visualization that the distal end 52 of a bougie 50 is approaching, at or past the distal end 22 by some increment. For example, when a first marker 54 is approaching the collar 14, the physician is alerted that the distal end 52 is about to exit the guide at end 22. The bougie can then be advanced a specified distance (e.g., 30mm) past the distal end 22 corresponding to aligning one or more of the indicators 54 with the collar 14.

[0031] Referring now to FIG. 5, once the distal end 52 of a bougie 50 is at the desired location within the trachea 34, the guide 10 is retracted along the path of the bougie 50 while the bougie is held in place to leave the distal end 52 of a bougie at the desired location in the trachea 34. The endotracheal tube (not shown) is then advanced over the bougie 50 into the trachea 34 to intubate the patient. Removing the guide 10 from the mouth prior to passing the endotracheal tube over the bougie and into the trachea minimizes risk of traumatic injury from the device to the mouth, larynx, or associated nerves.

[0032] From the description herein those skilled in the art readily will appreciate that the bougie guide can be adapted for various uses. For example, by attaching the appropriate adaptor to the proximal end of the guide, the guide may be connected to an oxygen source, such as a breathing circuit, in order to insufflate supplemental oxygen into the hypopharynx. This may be especially useful during the process of awake intubation. Another example is that, by inserting the distal tip of the guide through the glottic opening and into the upper trachea, positive pressure ventilation may be applied for the purpose of temporary rescue during critical, unplanned loss of airway and ventilation. The guide may be attached to a breathing circuit or other source of positive pressure ventilation for use in such an emergency. Accordingly, the guide provides versatility of use and can facilitate various treatment protocols.

Claims

1. An apparatus (10) for endotracheal intubation of a patient via a flexible bougie, the apparatus comprising: an elongate tube (12) having a distal (22) and proximal end; the elongate tube (12) having a central aperture (16) sized to receive a flexible bougie (50); the elongate tube (12) being sized to allow insertion in a patient's mouth and advancement through an oropharynx region of the patient such that the distal end (22) is located at or near a glottis of the patient while the proximal end is at or outside the patient's mouth; wherein the elongate tube (12) comprises a pre-formed curvilinear path corresponding to a natural curvature around a tongue region of the patient; the natural curvature having a first proximal curvilinear path (18) corresponding to the tongue region and a second curvilinear path (20) distal to and extending in a direction opposite the first curvilinear path to position and orient the distal end (22) of the elongate tube (12) at the glottis (36) and in substantial alignment with a path of a tracheal segment (34) distal of the glottis; characterized in that, the elongate tube (12) has a round cross-section that promotes rotation of the tube (12) within the patient and tapers so that the central aperture (16) is larger at the proximal end and smaller at the distal end (22).

2. The apparatus of claim 1, wherein the proximal end comprises a circular collar (14) with a thumb notch (15) allowing for manual purchase of the proximal end for advancement and rotation of the elongate tube (12) within the oropharynx region.

3. The apparatus of claim 2, wherein the notched circular collar (14) provides visual and tactile indication of the angular orientation of the elongate tube (12) with respect to the patient.

4. The apparatus of claim 1, wherein the elongate tube (12) has a length L of the order of 130 mm, and a height h of the order of 60mm.

5. The apparatus of claim 1, wherein the first proximal curvilinear path (18) comprises a first radius and the second curvilinear path (20) comprises a second radius smaller than the first radius.

6. The apparatus of claim 1, wherein the elongate tube (12) has sufficient rigidity and the second curvilinear path (20) is shaped with respect to the first curvilinear path (18) such that the distal end (22) naturally positions itself at a proper anterior-posterior location with respect to the glottis (36) and such that an exit path of a distal end of the bougie (50) when advanced past the distal end (22) of the elongate tube (12) is aligned with an opening of the glottis (36) and orientation of the trachea.

7. The apparatus of claim 1, wherein the elongate tube (12) comprises a non-reflective dark-colored plastic configured to minimizes videoscopic glare.

8. The apparatus of claim 1, further comprising: a flexible bougie (50) sized with sufficient length, diameter and flexibility to navigate through the central aperture (16) of the elongate tube (12).

9. The apparatus of claim 8: wherein the bougie (50) comprises one or more markers at a location along its length corresponding to the length along the central aperture (16) of the elongate tube (12); and wherein the one or more markers provide visualization that the distal end of a bougie (50) is near, at or past the distal end (22) of the elongate tube (12) by some increment.

10. The apparatus of claim 1, wherein said central aperture (16) has an internal diameter of the order of 15mm at the proximal end of the tube and an internal diameter of the order of 7mm at the distal end of the tube.