Reversible airway device and related method for ventilating a subject

One aspect of the present disclosure relates to a reversible airway device that includes a tubular guide, a laryngeal mask, an endotracheal tube, and a sealing mechanism. The tubular guide can have a distal end portion, a proximal end portion, and a first passageway extending between the distal and proximal end portions. The laryngeal mask can be attached to the distal end portion of the tubular guide. The laryngeal mask can include an opening in fluid communication with the first passageway. The endotracheal tube can be slidably disposed within the first passageway and have a second passageway that is concentric with the first passageway. The sealing mechanism can be disposed within the first passageway and be configured to occlude the flow of a gas through the first passageway.

TECHNICAL FIELD

The present disclosure relates generally to the field of anesthesiology and, more particularly, to a reversible airway device and related method for ventilating a subject using the airway device that does not risk disconnection or loss of the patient's airway during ventilation.

BACKGROUND

Airway devices are widely used in hospital surgical environments to provide respiratory assistance and ventilate patents during medical procedures. While there are a multitude of airway devices currently on the market, one popular airway device is an endotracheal tube and another is a supra-glottic support device, such as a laryngeal mask airway (LMA). While the use of these devices is widespread, there are disadvantages associated with each of these devices.

Endotracheal tubes, for example, are used to ventilate patients requiring anesthesia and/or respiratory assistance. An example of a conventional endotracheal tube is a plastic tube, which is inserted into a subject's mouth, passed down the trachea through the vocal cords, and lodged in the trachea proximal (or above) the lungs. The endotracheal tube may have a cuff or balloon portion surrounding the circumference of the endotracheal tube near the distal end that rests in the subject's trachea. After the endotracheal tube has been inserted properly, the cuff may be inflated to seal against the wall of the trachea. Once sealed, positive pressure ventilation may be used to provide respiratory assistance and, if desired, anesthesia or other gas, gas mix, etc., to the patient though the endotracheal tube via a ventilator. The cuff provides a seal that tends to block liquids and solids from passing along the outside of the endotracheal tube between the tube and the trachea wall and entering the subject's lungs.

A LMA typically includes a hollow tube (sometimes referred to as a tubular guide, tube or guide) and a laryngeal mask. The laryngeal mask of the LMA is intended to fit in the mouth of a patient and to cover the two openings leading, respectively, to the esophagus and the trachea, on the one hand, and blocking the fluid path to and from the esophagus and stomach, on the other hand, thereby providing a fluid path to the trachea and lungs for ventilating the patient. The laryngeal mask may be positioned without requiring a physician to view the airway directly. The laryngeal mask has an inflatable cuff or rim area. Once the laryngeal mask is placed into the subject's mouth, the cuff can be inflated to seal against the walls of the inside of the mouth and, if positioned properly, to block flow to and from the esophagus. A flexible, membranous support material extends from the cuff to form a recessed area, e.g., a space or volume, into which a gas mix can be pumped through the tube or other instrumentality of the LMA to provide the requisite air and/or anesthesia to the patient. The tube is of relatively large diameter, as compared to the usually relatively narrower diameter passage of a conventional endotracheal tube, and such relatively large diameter facilitates gas mix and exhalant flow with relatively minimal interference, pressure drop, etc. The support material supports the cuff from the tube. Thus, the LMA can be used to supply a gas mix to the recessed area and from there to the trachea.

In patients that require ventilation with an airway device (e.g., critically ill or injured subjects), it is important to maintain a continuous airway. In such patients, if ventilation begins with a supra-glottic support device (e.g., a LMA) and intubation subsequently becomes necessary, the supra-glottic support device must be removed from the patient so that an endotracheal tube can be placed. Doing so, however, requires that the patient's airway be temporarily disrupted while also increasing the risk that the patient's airway may not be recovered. Additionally, placing an endotracheal tube requires the skill of an experienced medical professional, who may not be present in all circumstances in which unexpected intubation is required.

SUMMARY

The present disclosure relates generally to the field of anesthesiology and, more particularly, to a reversible airway device and related method for ventilating a subject using the airway device that does not risk disconnection or loss of the patient's airway during ventilation.

One aspect of the present disclosure relates to a reversible airway device that includes a tubular guide, a laryngeal mask, an endotracheal tube, and a sealing mechanism. The tubular guide can have a distal end portion, a proximal end portion, and a first passageway extending between the distal and proximal end portions. The laryngeal mask can be attached to the distal end portion of the tubular guide. The laryngeal mask can include an opening in fluid communication with the first passageway. The endotracheal tube can be slidably disposed within the first passageway and have a second passageway that is concentric with the first passageway. The sealing mechanism can be disposed within the first passageway and be configured to occlude the flow of a gas through the first passageway.

Another aspect of the present disclosure relates to a reversible airway device that includes a tubular guide, a laryngeal mask, an endotracheal tube, a sealing mechanism and a stiffening mechanism. The tubular guide can have a distal end portion, a proximal end portion, and a first passageway extending between the distal and proximal end portions. The laryngeal mask can be attached to the distal end portion of the tubular guide. The laryngeal mask can include an opening in fluid communication with the first passageway. The endotracheal tube can be slidably disposed within the first passageway and have a second passageway that is concentric with the first passageway. The sealing mechanism can be disposed within the first passageway and be configured to occlude the flow of a gas through the first passageway. The stiffening mechanism can be operably connected to the laryngeal mask. The stiffening mechanism can be for selectively adjusting the position of the laryngeal mask relative to the airway of a subject.

Another aspect of the present disclosure can include a method for providing an artificial airway in a subject. One step of the method can include providing a reversible airway device. The airway device can include a tubular guide, a laryngeal mask, an endotracheal tube, and a sealing mechanism. The tubular guide can have a distal end portion, a proximal end portion, and a first passageway extending between the distal and proximal end portions. The laryngeal mask can be attached to the distal end portion and include an opening in fluid communication with the first passageway. The endotracheal tube can be slidably disposed within the first passageway and have a second passageway that is concentric with the first passageway. The sealing mechanism can be disposed in the first passageway. Next, the laryngeal mask can be inserted into the subject so that an airtight seal is formed between the laryngeal mask and the airway of the subject. After inserting the laryngeal mask, the endotracheal tube can be deployed so that a distal end of the endotracheal tube is positioned below the vocal cords of the subject. The endotracheal tube can then be retracted so that the distal end of the endotracheal tube is positioned above the vocal cords. A flow of gas through the second passageway is uninterrupted during the inserting and deploying steps.

DETAILED DESCRIPTION

Definitions

In the context of the present disclosure, the singular forms “a,” “an” and “the” can include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” and/or “comprising,” as used herein, can specify the presence of stated features, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and/or groups thereof.

As used herein, phrases such as “between X and Y” and “between about X and Y” can be interpreted to include X and Y.

As used herein, phrases such as “between about X and Y” can mean “between about X and about Y.”

As used herein, phrases such as “from about X to Y” can mean “from about X to about Y.”

Spatially relative terms, such as “under,” “below,” “lower,” “over,” “upper” and the like, may be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. It will be understood that the spatially relative terms can encompass different orientations of the apparatus in use or operation in addition to the orientation depicted in the figures. For example, if the apparatus in the figures is inverted, elements described as “under” or “beneath” other elements or features would then be oriented “over” the other elements or features.

As used herein, the terms “ventilating” or “ventilate” can refer to providing breathable air or oxygen, for example, and removing gas, etc., e.g., exhalant exhaled by a subject, and providing anesthesia and/or other materials to and/or from the lungs of a subject. The terms can also have the usual meaning as used in the field of medicine. The various gases, e.g., oxygen, air, anesthesia, etc., alone or in combination sometimes are referred to below collectively as a gas mixture.

Overview

The present disclosure relates generally to the field of anesthesiology and, more particularly, to a reversible airway device and related method for ventilating a subject using the airway device that does not risk disconnection or loss of the patient's airway during ventilation. As representative of one aspect of the present disclosure,FIG. 1illustrates a reversible airway device10for establishing an artificial airway and providing continuous ventilation in a subject when needed. Existing airway devices and associated methods for ventilating subjects involve the introduction of an endotracheal tube through a supra-glottic airway support device. This is time consuming, involves multiple devices, entails ventilation stoppage, and requires a high level of medical expertise. Advantageously, the present disclosure integrates both sub-glottic and supra-glottic support components that can easily and automatically provide intubation and, when needed, be quickly changed to function as a supra-glottic airway support while not compromising ventilation.

Reversible Airway Devices

One aspect of the present disclosure can include a reversible airway device10. The reversible airway device10can generally include a supra-glottic airway support12(e.g., comprising a tubular guide16and a laryngeal mask18), an endotracheal tube14, and a sealing mechanism20. By “reversible”, it is meant that an artificial airway provided by the supra-glottic airway support12can be readily exchanged for an artificial airway provided by the endotracheal tube14without removing or disconnecting any component(s) of the airway device10, and while maintaining continuous, uninterrupted ventilation. In other words, the term “reversible” can refer to the ability of the airway device10to be automatically changed from a supra-glottic airway support12to an endotracheal tube14, and then back to a supra-glottic airway support, without compromising ventilation. As discussed in more detail below, the airway device10of the present disclosure can be used for all indications of a supra-glottic airway support device where there is a possibility that endotracheal intubation may be necessitated (e.g., in trauma or critically ill patients).

As shown inFIG. 1, one component of the airway device10includes a supra-glottic airway support12. The supra-glottic airway support12can include a tubular guide16(e.g., a hollow tube) and a laryngeal mask18that surrounds, and is connected to, a distal end portion22of the tubular guide. The tubular guide16includes a first passageway (FIG. 2B) that extends between the distal end portion22(FIG. 1) and a proximal end portion26thereof. As discussed in more detail below, the first passageway24of the tubular guide16is sized and dimensioned to receive the endotracheal tube14. Also partially extending between the proximal and distal end portions26and22of the tubular guide16is a longitudinal slot27. The longitudinal slot27can serve as a rapid and convenient means for introducing the endotracheal tube14into the tubular guide16. When in use, the proximal end portion26of the tubular guide16remains outside of the subject's mouth and, therefore, is accessible to a healthcare provider (e.g., physician, nurse or other individual). The proximal end portion26of the tubular guide16may be conveniently of any size and shape to secure a variety of attachments (not shown) to the tubular guide (e.g., a syringe, an endoscope probe, a gas mix supply connection to receive a gas mix for ventilating, anesthetizing, etc., a patient, a drainage tube, etc.).

Typically, the size and shape of the tubular guide16are selected so that the distal end portion22can be readily inserted into a subject's mouth and upper airway with the laryngeal mask18substantially sealing the laryngeal inlet of the subject. The tubular guide16is generally J-shaped to follow the profile of a typical subject's airway through the mouth, over the tongue, and into the laryngopharynx region of the subject just above the opening to the larynx. The tubular guide16is shaped to prevent the subject's tongue and pharynx from obstructing access to the trachea. The tubular guide16can be made from one or a combination of materials, such as plastic, with sufficient strength and rigidity to keep the subject's teeth apart and to prevent the subject from biting down and collapsing the tubular guide. The tubular guide16(as well as the laryngeal mask18) can also be sized to accommodate a wide range of patient sizes (e.g., pediatric patients).

The laryngeal mask18can include an opening28in fluid communication with the first passageway24(FIGS. 2A-B). In some instances, the opening28can be beveled to substantially match the angle of the subject's laryngeal inlet after insertion of the supra-glottic airway support12into the subject's airway. In other instances, the laryngeal mask18can include a guide member30(FIGS. 4A-C) for directing the endotracheal tube14at a desired angle (e.g., to substantially match the angle of the subject's laryngeal inlet). The guide member30can comprise a piece of plastic, for example, disposed on a surface of the laryngeal mask18adjacent the opening28. In one example, the guide member30can have a rectangular shape and include a U-shaped cross-sectional profile. As shown inFIG. 4C, the guide member30can be disposed within the distal end portion22of the tubular guide16and extend partially outward therefrom. The angle A2formed by virtue of the guide member30can be customized depending upon the construction (e.g., length, width, thickness, etc.) of the guide member so that the angle A2is different from the angle A1(FIG. 4B), which is naturally formed by the bevel associated with the opening28of the laryngeal mask18.

The supra-glottic airway support12can further include an inflation tube32(FIG. 1) and an air valve34for inflating and deflating an inflatable portion36or member (e.g., a cuff) of the laryngeal mask18. In addition, the supra-glottic airway support12can include a central support member (not shown in detail) that is a flexible and somewhat elastic or yielding membranous material, which generally provides support for the laryngeal mask18. Additionally or optionally, the laryngeal mask18can include one or more suction ports (not shown). Each suction port can be in fluid communication with a vacuum or source of negative pressure (not shown). In one example, the laryngeal mask18can include one or more suction ports circumferentially spaced about the perimeter of the inflatable portion36. The suction port(s) can be used to remove secretions or fluid from the patient's airway during use of the airway device10.

In another aspect, the airway device10includes an endotracheal tube14that is slidably disposed within the first passageway24(FIGS. 2A-B) of the tubular guide16. By “slidably disposed”, it is meant that the endotracheal tube14is not fixed within the first passageway24so that it is incapable of telescoping through the tubular guide16. Rather, the term “slidably disposed” can mean that the endotracheal tube14is translatable along a longitudinal axis of the first passageway24(e.g., using tactile force). In some instances, substantially the entire length of the endotracheal tube14can extend through the first passageway24. The endotracheal tube14can be sized and dimensioned to ventilate a patient requiring anesthesia and/or respiratory assistance. In some instances, the endotracheal tube14can comprise a plastic tube that can be passed through the supra-glottic airway support12, past the vocal cords, and lodged in the trachea proximal (or above) the lungs. The endotracheal tube14can include a distal end38, a proximal end40, and a second passageway42that extends between the distal and proximal ends. With the endotracheal tube14disposed in the first passageway24, the second passageway42and the first passage way are concentric or coaxial with one another. Since the tubular guide16is sized and dimensioned to receive the endotracheal tube14, a diameter associated with the first passageway24can be greater than a diameter associated with the second passageway42.

The endotracheal tube14can include a cuff44or balloon portion surrounding the circumference of the endotracheal tube near the distal end38that rests in the patient's trachea. The cuff44can be inflated to seal against the wall of the trachea after the endotracheal tube14has been properly inserted into a subject. Once sealed, positive pressure ventilation may be used to provide respiratory assistance and, if desired, anesthesia or other gas, gas mix, etc., to the patient though the endotracheal tube14via a ventilator (not shown). The cuff38provides a seal that tends to block liquids and solids from passing along the outside of the endotracheal tube14between the tube and trachea wall and entering the patient's lungs. The endotracheal tube14can further include an inflation tube46(FIG. 1) and an air valve48for inflating and deflating the cuff44.

In another aspect, the airway device10includes a sealing mechanism20(FIGS. 2A-B) configured to occlude the flow of a gas, gas mix, etc., through the first passageway24. The sealing mechanism20is disposed within a portion of the first passageway24. The sealing mechanism20is configured to permit the endotracheal tube14to translate along the longitudinal axis of the tubular guide16, while simultaneously preventing a gas, gas mix, etc., to flow between the distal and proximal end portions22and26of the tubular guide. The sealing mechanism20is configured to form a fluid-tight seal between an inner surface50(FIG. 3B) of the first passageway24and an outer surface52of the endotracheal tube14. As discussed in more detail below, the sealing mechanism20(FIGS. 2A-B) imparts the airway device10with the ability to change from the supra-glottic airway support12to an endotracheal tube14(and back again) by providing a single, common airway (i.e., the second passageway) that is not disrupted or stopped when the ventilation needs of the patient change.

In some instances, the sealing mechanism20can include one or more sealing members54configured to directly contact, and encircle, a portion of the outer surface52(FIG. 3B) of the endotracheal tube14. In one example, a sealing member54(FIG. 3A) can include an O-ring, a gasket, an inflatable cuff or cushion, or the like. As shown inFIG. 3A, the sealing member54can comprise an O-ring having outer and inner circumferential surfaces56and58that are configured to directly contact the inner surface50of the first passageway24and the outer surface52of the endotracheal tube14, respectively. By “directly contact”, is meant that there are no intervening structures, components, elements, surfaces, etc., between a first structure or surface (e.g., the inner surface50) and a second structure or surface (e.g., the outer surface56). Although the sealing member54is shown and described as being located at the distal end portion22(FIGS. 2A-B) of the tubular guide16, it will be appreciated that the sealing member can be located at any point within the tubular guide. Additionally, it will be appreciated that two, three, or more sealing members54can be used to form the sealing mechanism20.

Another aspect of the present disclosure can include a reversible airway device10′ (FIG. 5) that includes a stiffening mechanism60. Other than the stiffening mechanism60, the airway device10′ can be identically constructed as the airway device10inFIG. 1. The stiffening mechanism60can be configured to allow a user to selectively adjust the position of the laryngeal mask18, for example, when the supra-glottic airway support12is implanted in the airway of a subject. As shown inFIG. 5, the stiffening mechanism60can be operably coupled to the supra-glottic airway support12. In one example, the stiffening mechanism60can comprise tubing62that is securely connected to the tubular guide16via a fastening mechanism64, such as a band, clamp, rivet or other device. A wire (not shown) can extend from a proximal end66to a distal end68of the tubing62. The wire can be controllable by a handle70, which is operably connected to the proximal end66of the tubing62. In use, a user can operate the handle70to adjust the tension associated with the wire and thereby control movement of the laryngeal mask18during and/or after insertion of the supra-glottic airway support12into a subject's airway.

Methods

Another aspect of the present disclosure includes a method72(FIG. 6) for providing an artificial airway in a subject. Although supra-glottic airway devices, such as LMAs, are known as rescue devices that are easy to use in less trained hands, such devices are not a definite airway. Current methods for changing a supra-glottic airway support device to an endotracheal tube involve using different devices; however, such methods risk the danger of disconnection and/or loss of the airway. As described below, the method72of the present disclosure advantageously provides a technique for maintaining the airway of a subject while changing between different forms of airway assistance. A high level of skill is not required to perform the method72, which makes the present disclosure ideal for first responders, EMS personnel, etc., that may need to quickly change from a supra-glottic airway support device to an endotracheal tube (and back) without the requisite level of skill.

The method72can generally include the steps of providing a reversible airway device10(Step74), inserting a laryngeal mask18of the airway device into a subject (Step76), forming an airtight seal between the laryngeal mask and the airway (Step78), deploying an endotracheal tube14of the airway device (Step80), and retracting the endotracheal tube (Step82). Referring toFIGS. 7-9, a patient is shown schematically with the mouth open in cross-section and leading to the back of the throat (sometimes the mouth and/or throat are referred to as the oral cavity of the patient), and from there to the trachea via the laryngeal inlet, which provides an airway that leads to the lungs.

At Step74, the method72can include providing a reversible airway device10. The reversible airway device10can be constructed in an identical or similar manner as shown inFIG. 1and described above. Alternatively, the airway device10can be constructed in an identical or similar manner as the airway device10′ shown inFIG. 5and described above. For the purpose of illustration only, the method72will be described below using the airway device10ofFIG. 1. It will be appreciated that the airway device10can be sized and dimensioned to accommodate a variety of patient sizes, such as pediatric patients.

After selecting an appropriately-sized airway device10, the laryngeal mask18can be inserted into the oral cavity (mouth) of the subject (Step76). As shown inFIG. 7, the laryngeal mask18and its support member can then be positioned in the patient so that a lower portion of the laryngeal mask substantially blocks the esophagus to minimize the risk of regurgitation of stomach contents and the passage of air into the stomach. An upper portion of the laryngeal mask18also guides the distal end portion22of the tubular guide16into alignment using the laryngeal inlet of the patient as a guide to insert along the patient's airway, which is partially represented by the arrow84.

Once inserted, the inflatable portion36of the laryngeal mask18can be inflated through the inflation tube32so that the upper portion of the laryngeal mask substantially fills the patient's laryngopharynx at the level of the laryngeal inlet. At Step78, the upper portion of the laryngeal mask18surrounds the laryngeal inlet so that the opening28of the laryngeal mask is substantially sealed in fluid communication with the laryngeal inlet, e.g., pressing against walls of the oral cavity portions of the patient. Thus, substantially all of the gas inhaled or exhaled by the patient passes through the second passageway42of the endotracheal tube14.

The endotracheal tube14of the airway device10can then be deployed, if necessary, at Step80. The endotracheal tube14can be deployed automatically or under direct fiberoptic view. As shown inFIG. 8, the proximal end40of the endotracheal tube14can be urged downward through the tubular guide16using, for example, tactile force. As the endotracheal tube14is advanced, the distal end38emerges from the opening28of the laryngeal mask18and passes through the vocal cords of the patient until the cuff44of the endotracheal tube is positioned distal (below) the vocal cords. Next, the cuff44of the endotracheal tube14can be inflated to seal against the wall of the trachea. Once sealed, positive pressure ventilation may be used to provide respiratory assistance and, if desired, anesthesia or other gas, gas mix, etc., to the patient though the second passageway42of the endotracheal tube14via a ventilator.

When intubation with the endotracheal tube14is no longer necessary, the cuff44can be deflated and the distal end38withdrawn into the tubular guide16as shown inFIG. 9(Step82). Since an airtight seal is still maintained between the laryngeal mask18and the laryngeal outlet, ventilation of the patient can continue uninterrupted through the second passageway42upon discontinuing ventilation with the endotracheal tube14. Alternatively, if there is a failure of intubation using the endotracheal tube14, the airway device10can be changed to the supra-glottic airway support12without compromising ventilation since the airtight seal is maintained.

From the above description of the present disclosure, those skilled in the art will perceive improvements, changes and modifications. For example, it will be appreciated that order of steps can be changed so that the endotracheal tube14is deployed before Step78of the method72. Such improvements, changes, and modifications are within the skill of those in the art and are intended to be covered by the appended claims. All patents, patent applications, and publication cited herein are incorporated by reference in their entirety.