Patent Description:
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.

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 <NUM>% 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 <NUM>%. However, visualization does not guarantee successful endotracheal intubation.

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.

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.

<CIT> 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.

<CIT> discloses an oral airway (<NUM>) that includes an elongate tubular member (<NUM>) having a distal (<NUM>) and a proximal end (<NUM>) with an enlarged wedge-shaped housing (<NUM>) at the distal end. The wedge-shaped housing (<NUM>) is for insertion into the mouth (<NUM>) 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 (<NUM>) has anterior (<NUM>) and posterior (<NUM>) walls forming an enlarged proximal portion (<NUM>) tapering to a smaller distal portion (<NUM>) with a leading opening (<NUM>) separating the anterior (<NUM>) and posterior (<NUM>) walls at the distal end of the housing. A grate (<NUM>) covers the leading opening. Sidewalls (<NUM>, <NUM>) extend between the anterior (<NUM>) and posterior (<NUM>) walls and the wedge-shaped housing (<NUM>) is configured so that the sidewalls abut the ary epiglottic folds (<NUM>) as the wedge-shaped housing is inserted into the hypopharynx (<NUM>) of a patient to arrest insertion of the wedge-shaped housing and seat the wedge-shaped housing with the leading opening (<NUM>) adjacent to the glottis (<NUM>).

<CIT> 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.

<CIT> discloses embodiments directed to a bougie device and methods of use thereof, the device directing the deployment of an endotracheal tube through the larynx.

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.

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.

The technology described herein will be more fully understood by reference to the following drawings which are for illustrative purposes only:.

<FIG> 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.

Referring to <FIG>, an embodiment of a bougie guide apparatus <NUM> in accordance with the present description is shown installed in glottis <NUM> for access of the trachea <NUM> after placement of a video laryngoscope blade <NUM>. The video laryngoscope blade <NUM> acts to push the tongue <NUM> anteriorly and out of the line of vision, and the distal tip of the blade <NUM> is configured to curve around the tongue <NUM> to the epiglottis <NUM>. The distal end of the blade <NUM> comprises a camera <NUM> for visualization of the patient anatomy and glottis <NUM>.

In the embodiment shown the bougie guide <NUM> comprises an elongate tube <NUM> having a collar <NUM> at its proximal end, with the tube <NUM> having a tapered, curved shape terminating at distal end <NUM>. The tube <NUM> comprises a central aperture <NUM> the extends from the collar <NUM> at the proximal end to the distal end <NUM> for passage of a bougie.

The tube <NUM> comprises a primary or first curvature <NUM> that is sized and angled to follow path of blade <NUM> at least partially along its length. However, as shown in <FIG>, the orientation of the blade <NUM> with respect to the glottis <NUM> and trachea is hyperangulated with respect to the glottis <NUM> and trachea <NUM>, 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 <NUM>.

To accommodate these anatomical difficulties, the tube <NUM> comprises a second curvature <NUM> that is distal to first curvature <NUM>. The second curvature <NUM> reverses course of the first curvature <NUM> to form a subtle "s" shape that positions and orients the distal end <NUM> of the guide <NUM> at the glottis <NUM>, preferably at an angle substantially aligned with path of the trachea <NUM>.

<FIG> show side and front views, respectively, of the bougie guide <NUM> in detail. Elongate tube <NUM> comprises a circular cross-section that tapers from the proximal end, with an internal diameter DI that is larger than the diameter DI2 at the distal end <NUM>. In one embodiment, internal diameter DI of central aperture <NUM> is approximately <NUM> at the collar <NUM>, and the internal diameter DI2 is approximately <NUM>.

In the embodiment shown in <FIG> the tube <NUM> has a straight section that slopes slightly from the collar <NUM>, and leads into first curvature <NUM> having a radius r<NUM> that is generally larger than second curvature <NUM> having radius r<NUM>. The curvature leading through r<NUM> is generally configured to follow the natural curvature of the tongue <NUM>, (approximately <NUM>° to <NUM>°). While curvatures <NUM> and <NUM> are shown having a radius, it is appreciated that curvatures <NUM> and <NUM> may comprise any curvilinear shape or path.

The collar <NUM> is generally circular in shape, having a thickness t of approximately <NUM>, and diameter D<NUM> of approximately <NUM>. The collar <NUM> has a thumb notch <NUM> to help with administering and/or rotating the guide <NUM>, and as well providing a tactile (and visual) indicator or clocking of the rotational position of the guide <NUM> in the patient.

In one embodiment the overall length L of the guide <NUM> is approximately <NUM>, and the height h is approximately <NUM>.

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 <NUM> may have smaller dimensions for small patients/children).

The overall length L of the guide <NUM> is sized so that the distal end <NUM> can extend to or past the glottis <NUM> while the collar <NUM> 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 <NUM>, along with notch <NUM> in collar <NUM>, allow for easy rotation within the oropharynx when guiding the distal end <NUM> of tube <NUM> to the target location. The wall thickness of the tube <NUM> is generally about <NUM> to <NUM>, with sufficient material for rigidity to maintain its preformed curvature, while also being slightly compliant to deflect when necessary.

In a preferred embodiment, the tube <NUM> is constructed from a non-reflective dark-colored plastic that minimizes videoscopic glare. While any number of materials may be selected, the tube <NUM> 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 <NUM> to minimize friction between anatomy and components. In a preferred configuration the guide <NUM> is single use.

A preferred method for endotracheal intubation using the pre-shaped, curvilinear bougie guide <NUM> of the present description is detailed in <FIG>, <FIG> and <FIG>.

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

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

<FIG> is a schematic side-section view of the bougie guide <NUM> with a distal end <NUM> of a bougie <NUM> being delivered into the trachea <NUM>. The bougie <NUM> is preferably sized with sufficient length, diameter and flexibility to navigate through the length of the tube <NUM>. One exemplary bougie configuration is <NUM> Fr × <NUM> with Coude tip (e.g. model <NUM>-<NUM>-<NUM> by SunMed (www. With the distal end <NUM> of the guide <NUM> installed at the target location at the glottis <NUM>, the flexible (atraumatic) bougie <NUM> is inserted in aperture <NUM> at the proximal collar <NUM> and advanced along the length of the tube <NUM>. The taper of the tube <NUM> with the larger diameter at the proximal end <NUM> 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 DI2 to allow for sufficient passage of the bougie <NUM>.

When the distal end <NUM> of a bougie <NUM> reaches distal end <NUM> of the guide <NUM>, it is positioned at the glottis <NUM> and lined up with the trachea <NUM> (as a result of the curvatures <NUM>/<NUM> in the tube <NUM>) so that it easily passes through vocal folds of the glottis <NUM> and into the trachea <NUM>. Placement of the distal end <NUM> may be verified under videoscopic visualization.

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

Referring now to <FIG>, once the distal end <NUM> of a bougie <NUM> is at the desired location within the trachea <NUM>, the guide <NUM> is retracted along the path of the bougie <NUM> while the bougie is held in place to leave the distal end <NUM> of a bougie at the desired location in the trachea <NUM>. The endotracheal tube (not shown) is then advanced over the bougie <NUM> into the trachea <NUM> to intubate the patient. Removing the guide <NUM> 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.

Claim 1:
An apparatus (<NUM>) for endotracheal intubation of a patient via a flexible bougie, the apparatus comprising:
an elongate tube (<NUM>) having a distal (<NUM>) and proximal end;
the elongate tube (<NUM>) having a central aperture (<NUM>) sized to receive a flexible bougie (<NUM>);
the elongate tube (<NUM>) being sized to allow insertion in a patient's mouth and advancement through an oropharynx region of the patient such that the distal end (<NUM>) 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 (<NUM>) 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 (<NUM>) corresponding to the tongue region and a second curvilinear path (<NUM>) distal to and extending in a direction opposite the first curvilinear path to position and orient the distal end (<NUM>) of the elongate tube (<NUM>) at the glottis (<NUM>) and in substantial alignment with a path of a tracheal segment (<NUM>) distal of the glottis;
characterized in that,
the elongate tube (<NUM>) has a round cross-section that promotes rotation of the tube (<NUM>) within the patient and tapers so that the central aperture (<NUM>) is larger at the proximal end and smaller at the distal end (<NUM>).