Stabilizing rod

Abstract

The present invention provides a stabilizing rod and methods for accessing a difficult airway by intubating a subject using the stabilizing rod. The stabilizing rod includes a distal end comprising at least one section having a reduced outer diameter as compared to another more proximal section; a proximal end adapted and configured for selective engagement with at least one of a videoscope and a positive-pressure ventilation device; a largest outer diameter adapted and configured for passing through an inner diameter of a laryngeal mask airway (LMA); and a hollow bore extending between the distal end and the proximal end, the hollow bore being adapted and configured to receive a portion of the videoscope therein.

Description

[0001] STABILIZING ROD

[0002] CROSS-REFERENCE TO RELATED APPLICATIONS

[0003] The present application claims priority under 35 U.S.C. § 119(e) to U.S. Provisional Patent Application No. 63 / 639,888, filed April 29, 2024, which application is incorporated herein by reference in its entirety.

[0004] BACKGROUND OF THE INVENTION

[0005] There are many instances in which patients require endotracheal intubation. Some patients present with either a known difficult airway, or signs or symptoms suggestive that endotracheal intubation may be difficult. In these clinical situations, a provider tasked with performing airway management may have difficulty with facemask ventilation, difficulty with tracheal intubation, or both. Both adult and pediatric subjects can present with a difficult airway, albeit with different underlying risk factors suggestive of difficulty. Per the American Society of Anesthesiologists (ASA) difficult airway algorithm, during a “cannot intubate, cannot ventilate” or “cannot intubate, can ventilate” scenario, a supraglottic airway, which is usually a laryngeal mask airway (LMA) is the default rescue device to oxygenate and ventilate the patient. The LMA can also serve as a conduit for endotracheal tube (ETT) placement when a definitive airway is required.

[0006] Various techniques have been described to intubate through an LMA, including the use of airway exchange catheters, (Aintree intubation catheter®, Cook Medical), guidewires, and gum elastic bougie. However, these techniques require the operator to perform an airway exchange without direct visualization of the trachea. This has the possibility of either accidental extubation or damage to upper airway stmctures. In patients that are already difficult to ventilate, this is potentially deleterious. Indeed, the ASA closed claims database demonstrates some of the largest awards have gone to plaintiffs for damages related to airway management or loss. The inability to intubate through and remove an LMA under direct visualization while retaining the ability to oxygenate and ventilate remains a severe limitation in airway management.

[0007] Accordingly, there remains a need in the art for articles and methods that improve on existing articles and methods for intubation, particularly for patients with difficult airways. The present disclosure meets this need. SUMMARY

[0008] In one aspect, a stabilizing rod includes a distal end comprising at least one section having a reduced outer diameter as compared to another more proximal section; a proximal end adapted and configured for selective engagement with at least one of a videoscope and a positive-pressure ventilation device; a largest outer diameter adapted and configured for passing through an inner diameter of a laryngeal mask airway (LMA); and a hollow bore extending between the distal end and the proximal end, the hollow bore being adapted and configured to receive a portion of the videoscope therein.

[0009] In some embodiments, the stabilizing rod is rigid or partially rigid. In some embodiments, the stabilizing rod is fabricated from one or more selected from the group consisting of: metal and plastic, In some embodiments, the stabilizing rod has a mass of 1,000 g or less. In some embodiments, the stabilizing rod has a length between 4 cm and 20 cm. In some embodiments, the stabilizing rod can withstand at least 20 Ibf of applied force.

[0010] In some embodiments, the at least one section having a reduced outer diameter is adapted and configured to engage with an endotracheal tube (ETT). In some embodiments, the reduced outer diameter is further adapted and configured to form a fluid tight seal with the ETT. In some embodiments, the at least one section having a reduced outer diameter comprises a plurality of proximally ascending outer diameters and shoulders adapted and configured to engage with an inner diameter of a variety of endotracheal tubes (ETTs). In some embodiments, each outer diameter is adapted and configured to form a fluid tight seal with one or more particular ETT sizes.

[0011] In some embodiments, the stabilizing rod further includes a quick release feature, the quick release feature adapted and configured to disengage the stabilizing rod from an endotracheal tube (ETT). In some embodiments, the quick release feature comprises a telescoping element coupled to an actuating element, the telescoping element being adapted and configured to disengage the ETT from the distal end of the stabilizing rod when the actuating element is actuated.

[0012] In some embodiments, the stabilizing rod further includes an attachment port for sampling CO2.

[0013] In some embodiments, the proximal end further comprises a handle, the handle being adapted and configured to grasp, and maintain the position of, the stabilizing rod during use. In some embodiments, the handle comprises one or more selected from: latching loops and gripped handles.

[0014] In another aspect, a method of placing an endotracheal tube in a subject includes placing a laryngeal mask airway (LMA) with its cuffed end within the subject’s oro-hypopharynx; engaging an endotracheal tube (ETT) with a distal end of the stabilizing rod according to any of the embodiments disclosed herein; loading the stabilizing rod onto a videoscope; inserting the ETT into the LMA; and guiding positioning of the ETT with the videoscope.

[0015] In some embodiments, the loading of the stabilizing rod onto the videoscope includes passing a portion of the videoscope through the hollow bore of the stabilizing rod. In some embodiments, the loading of the stabilizing rod onto the videoscope further includes passing a portion of the videoscope through the ETT.

[0016] In some embodiments, guiding positioning of the ETT with the videoscope includes advancing the ETT through the lumen of the LMA until the subject’s vocal cords and trachea are observed through the videoscope.

[0017] In some embodiments, the method further includes proximally withdrawing the LMA while maintaining a position of the ETT and videoscope with the stabilizing rod. In some embodiments, the method further includes unloading the stabilizing rod from the videoscope and withdrawing the videoscope while maintaining a position of the ETT with the stabilizing rod. In some embodiments, the method further includes removing the stabilizing rod and withdrawing the LMA;

[0018] In some embodiments, the method further includes confirming placement of the ETT. In some embodiments, confirming the placement of the endotracheal tube includes ventilating and checking end tidal carbon dioxide, passing the videoscope through endotracheal tube again to visualize, or a combination thereof.

[0019] In some embodiments, the method further includes coupling a positive-pressure ventilation device to the proximal end of the stabilizing rod and ventilating the subject through the stabilizing rod and the endotracheal tube.

[0020] BRIEF DESCRIPTION OF THE DRAWINGS

[0021] For a fuller understanding of the nature and desired objects of the present invention, reference is made to the following detailed description taken in conjunction with the accompanying drawing figures wherein like reference characters denote corresponding parts throughout the several views.

[0022] FIGS. 1A-B depict exemplary stabilizing rods according to embodiments disclosed herein. (A) Adult stabilizing rod including a step-down in diameter forming stops for engaging with an endotracheal tube (ETT) of varying sizes between sections 1 and 2 as well as between sections 2 and 3. (B) Pediatric stabilizing rod including a step-down in diameter forming a stop for engaging with an ETT of varying sizes between sections 1 and 2.

[0023] FIGS. 2A-C depict illustrations of endotracheal tube placement with the stabilizing rod according to one or more embodiments of the present disclosure.

[0024] FIG. 3 depicts the top part of an endotracheal tube (ETT) for measuring the stabilizing rod’s bottom interface measurement.

[0025] FIGS. 4A-C depict images of a stabilizing rod passing through a laryngeal mask airway (LMA) according to one or more embodiments of the present disclosure. (A) An exemplary laryngeal mask airway (LMA) highlighting the cut location for measuring the inner diameter and for determining rod outer diameter. (B) Cross-section of a stabilizing rod engaged with a videoscope, ETT, and LMA, according to an embodiment of the disclosure. (C) Cross-section of a stabilizing rod (blue) when engaged with a videoscope, ETT, and LMA, according to an embodiment of the disclosure.

[0026] FIGS. 5A-B depict exemplary adult (FIG. 5A) and pediatric (FIG. 5B) stabilizing rods according to one or more embodiments of the present disclosure.

[0027] FIG. 7 provides a front and side view of a stabilizing rod including foldable handle loops as contemplated herein.

[0028] FIGS. 8A-B depict a detachable handle assembly according to one or more embodiments of the present disclosure. (A) An exemplary detachable handle assembly. (B) A schematic illustrating an exemplary process for assembling the stabilizing rod and handle assembly.

[0029] FIG. 9 depicts a stabilizing rod including a lever for quick release of an ETT and an attachment for sampling CO2 according to one or more embodiments of the present disclosure.

[0030] FIGS. 10A-C depict the locations of where the fixed constraint is applied on the rod model. (A) The non-circular shape of the loop in the initial rod provides multiple locations for tight grip. (B-C) The semi-circular lip / latches of the revised rod evenly distributes the effect (applied force) of the pressing finger. FIG. 11 illustrates three different locations where forces are applied in the initial rod design.

[0031] FIG. 12 depicts the locations where forces are applied on the handle assembly in the revised rod design.

[0032] FIG. 13 depicts the von-Mises stresses for the applied forces at location 1 in the initial rod design. 10 Ibf of compressive force is applied in this simulation. It was observed that the circled return of the loop has a stress close to the tensile strength of the ABS material.

[0033] FIG. 14 depicts the von-Mises stresses when 10 Ibf of force is applied at location 2. As indicated, in the force map, the loop fails.

[0034] FIG. 15 depicts the von-Mises stresses when 10 Ibf of force is applied at location 3. As indicated, the loop fails in this scenario as well. Furthermore, in this force application position, the rod stem fails as well as the loop.

[0035] FIG. 16 depicts the von-Mises stresses under 10 Ibf of applied force on the revised pediatric rod made with ABS material.

[0036] FIG. 17 depicts the von-Mises stresses under 20 Ibf of applied force on the revised pediatric rod design made with ABS material.

[0037] FIG. 18 depicts the von-Mises stresses under 20 Ibf of applied force on the revised pediatric rod design made with SS material.

[0038] FIG. 19 depicts a stabilizing rod (upper inset) and the stabilizing with attached ETT loaded onto a videoscope. ETT indicates endotracheal tube.

[0039] DEFINITIONS

[0040] The instant invention is most clearly understood with reference to the following definitions.

[0041] As used herein, the singular form “a,” “an,” and “the” include plural references unless the context clearly dictates otherwise.

[0042] Unless specifically stated or obvious from context, as used herein, the term “about” is understood as within a range of normal tolerance in the art, for example within 2 standard deviations of the mean. “About” can be understood as within 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, 0.5%, 0.1%, 0.05%, or 0.01% of the stated value. Unless otherwise clear from context, all numerical values provided herein are modified by the term about. As used herein, the terms “subject” and “patient” are used interchangeably. As used herein, a subject is preferably a mammal such as a non-primate (e.g., cows, pigs, horses, cats, dogs, rats, etc.) and a primate (e.g., monkey and human), most preferably a human.

[0043] As used in the specification and claims, the terms “comprises,” “comprising,” “containing,” “having,” and the like can have the meaning ascribed to them in U.S. patent law and can mean “includes,” “including,” and the like.

[0044] Unless specifically stated or obvious from context, the term “or,” as used herein, is understood to be inclusive.

[0045] Ranges provided herein are understood to be shorthand for all of the values within the range. For example, a range of 1 to 50 is understood to include any number, combination of numbers, or sub-range from the group consisting 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, or 50 (as well as fractions thereof unless the context clearly dictates otherwise).

[0046] DETAILED DESCRIPTION OF THE INVENTION

[0047] Device

[0048] Provided herein are stabilizing rods for intubating through a laryngeal mask airway (LMA) for subjects with a difficult airway. A difficult airway may include the clinical situation in which a conventionally trained provider tasked with performing airway management may have difficulty with facemask ventilation, difficulty with tracheal intubation, or both. Suitable subjects include both pediatric and adult subjects with a difficult airway in need of intubation thereof. As such, referring to FIGS. 1A and IB, a stabilizing rod 100 according to the embodiments disclosed herein may be configured for adult patients 100a (FIG. 1A) or pediatric patients 100b (FIG. IB). Unless stated otherwise, the features of the stabilizing rod discussed herein apply to both the adult stabilizing rod 100a and the pediatric stabilizing rod 100b.

[0049] The stabilizing rod 100 includes a proximal end 110, a distal end 120, and a hollow bore 130 extending therebetween. In some embodiments, as illustrated in FIGS. 2A-C, the proximal end is adapted and configured for selectively engaging with a videoscope and / or a positivepressure ventilation device 200 (e.g., standard ventilator circuit / endotracheal tube adapter, bagmask ventilator bag, Jackson Reese type circuit or capnometer coupling). For example, the proximal end may include a universal ventilator adaptor 111 (FIGS. 1 A-B) for engaging with one or more ventilation devices, such as, but not limited to, a bag ventilator 201 and / or oxygen reservoir 203, a mechanical ventilator, or the like. Additionally, or alternatively, in some embodiments, the proximal end includes a clip-on or friction-based element to mount onto a videoscope such that the device with the engaged ETT remains securely fixed. In some such embodiments, the videoscope may be used to provide oxygenation via its internal channel when mounted thereto.

[0050] Referring to FIGS. 1A-3, in some embodiments, the distal end of the device is adapted and configured to engage with an endotracheal tube (ETT) 300 (FIG. 3). For example, in some embodiments, as illustrated in FIGS. 1A and IB, the distal end of the stabilizing rod 100 includes at least one distal section 121 having a reduced outer diameter as compared to another, more proximal section (e.g., section 1 as compared to section 2, section 2 as compared to section 3, etc.). In some embodiments, the stabilizing rod 100 also includes a shoulder 123 formed at the end of at least one of the sections, the shoulder extending radially from the smaller outer diameter of the more distal section to the larger outer diameter of the more proximal section. The sections and / or corresponding shoulders may be adapted and configured to engage with specific ETT sizes. For example, in some embodiments, the outer diameter of each of the sections is configured to form a snug or air tight seal with one or more specific ETT sizes positioned thereon. Additionally, or alternatively, each of the shoulders may be configured to form a stop that prevents specific ETT sizes from sliding past the shoulder and onto / over another section. In some embodiments, when the proximal end of the stabilizing rod is mounted to the videoscope and the distal end is engaged with the ETT, the ETT is positioned at a handle side of the videoscope.

[0051] The stabilizing rod may include any suitable number of sections and / or shoulders. For example, as illustrated in FIG. 1 A, the stabilizing rod 100 may include a plurality of sections with proximally ascending outer diameters and shoulders, each of the sections being adapted and configured to engage with an inner diameter of a different ETT size. Alternatively, in some embodiments, as illustrated in FIG. IB, the stabilizing rod includes two sections with a single shoulder. In some embodiments, the stabilizing rod shown in FIG. 1A forms an adult stabilizing rod and the stabilizing rod shown in FIG. IB forms a pediatric stabilizing rod. As will be appreciated by those skilled in the art, the sections and / or shoulders of each stabilizing rod may be configured to engage with any suitable ETT size. For example, referring again to FIG. 1 A, in some embodiments, the shoulder between sections 1 and 2 of the stabilizing rod is adapted and configured to form a stop for size 6 and 7 ETTs, while the shoulder between sections 2 and 3 is adapted and configured to form a stop for a size 8 ETT. Additionally, or alternatively, in some embodiments, section 1 of the adult stabilizing rod 100a has an outer diameter of from about 5 mm to about 5.5 mm, from about 5.5 mm to about 6 mm, from about 6 mm to about 6.5 mm, from about 6.5 mm to about 7 mm, from about 7 mm to about 7.5 mm, or any and all increments therebetween. In some embodiments, the outer diameter of section 1 of the adult stabilizing rod is about 7.1 mm. In some embodiments, section 2 of the adult stabilizing rod 100a has an outer diameter of from about 6 mm to about 6.5 mm, from about 6.5 mm to about 7 mm, from about 7 mm to about 7.5 mm, from about 7.5 mm to about 8 mm, from about 8 mm to about 8.5 mm, from about 8.5 mm to about 9 mm, from about 9 mm to about 9.5 mm, from about 9.5 mm to about 10 mm, or any and all increments therebetween. In some embodiments, section 2 of the adult stabilizing rod 100a has an outer dimeter of about 9 mm. In some embodiments, section 3 of the adult stabilizing rod 100a has an outer diameter of from about 8 mm to about 8.5 mm, from about 8.5 mm to about 9 mm, from about 9 mm to about 9.5 mm, from about 9.5 mm to about 10 mm, from about 10 mm to about 10.5 mm, from about 10.5 mm to about 11 mm, from about 11 mm to about 11.5 mm, from about 11.5 mm to about 12 mm, from about 12 mm to about 12.5 mm, from about 12.5 mm to about 13 mm, or any and all increments therebetween. In some embodiments, section 3 of the adult stabilizing rod has an outer diameter of about 11.5 mm.

[0052] Referring now to FIG. IB, in some embodiments, the shoulder between sections 1 and 2 of the pediatric stabilizing rod 100b is adapted and configured to form a stop for size 4.5, 5, and / or 5.5 ETTs. Additionally or alternatively, in some embodiments, section 1 of the pediatric stabilizing rod 100b has an outer diameter of from about 3 mm to about 3.5 mm, from about 3.5 mm to about 4 mm, from about 4 mm to about 4.5 mm, from about 4.5 mm to about 5 mm, from about 5 mm to about 5.5 mm, from about 5.5 mm to about 6 mm, from about 6 mm to about 6.5 mm, or any and all increments therebetween. In some embodiments, section 1 of the pediatric stabilizing rod 100b has an outer diameter of about 5.4 mm. In some embodiments, section 2 of the pediatric stabilizing rod 100b has an outer diameter of from about 5 mm to about 5.5 mm, from about 5.5 mm to about 6 mm, from about 6 mm to about 6.5 mm, from about 6.5 mm to about 7 mm, from about 7 mm to about 7.5 mm, from about 7.5 mm to about 8 mm, from about 8 mm to about 8.5 mm, from about 8.5 mm to about 9 mm, or any and all increments therebetween. In some embodiments, section 2 of the pediatric stabilizing rod 100b has an outer diameter of about 7 mm.

[0053] Turning to FIGS. 4A-C, in some embodiments, the stabilizing rod 100 is adapted and configured to engage one or more ETTs while permitting an LMA to pass freely over at least a portion thereof. For example, in some embodiments, the adult stabilizing rod 100a is adapted and configured to permit a size 3 LMA to pass freely over at least a portion thereof. Additionally, or alternatively, in some embodiments, the pediatric stabilizing rod 100b is adapted and configured to permit size 2 and 2.5 LMAs to pass freely over at least a portion thereof.

[0054] Still referring to FIGS. 4A-C, in some embodiments, the hollow bore is adapted and configured to permit a scope (e.g., videoscope) to pass therethrough. The hollow bore can include any suitable cross-sectional dimension for permitting the scope to pass therethrough. Suitable cross-sectional dimensions of the hollow bore include, but are not limited to, at least 3 mm, at least 4 mm, at least 5 mm, from about 3 mm to about 3.5 mm, from about 3.5 mm to about 4 mm, from about 4 mm to about 4.5 mm, from about 4.5 mm to about 5 mm, from about 5 mm to about 5.5 mm, from about 5.5 mm to about 6 mm, from about 6 mm to about 6.5 mm, or any and all increments therebetween. For example, in some embodiments, the hollow bore has a cross-sectional dimension of about 4 mm. In some embodiments, the hollow bore has a minimum cross-sectional dimension of at least 5 mm.

[0055] In some embodiments, the stabilizing rod 100 includes one or more grasping features for easy pushing-pulling during the ETT-LMA exchange (pushing ETT into trachea to appropriate location, then pulling LMA out while holding ETT in place). For example, in some embodiments, as illustrated in FIGS. 5A-B, the proximal end of the stabilizing rod 100 includes a handle assembly 500 having one or more handles 510 for stabilizing the rod during use. The handle assembly 500 may include any suitable handle(s) 510 for stabilizing the rod, such as, but not limited to, open loops 511 (FIG. 6A), closed loops 513 (FIG. 6B), or any other grips or handles as understood in the art. In some embodiments, the handles include a gripping surface such as a textured surface, a non-slip surface such as a rubberized non-slip surface, and the like. In some embodiments, the handle assembly 500 may include foldable handle(s), as depicted in FIG. 7. For example, in some embodiments the 2 or more open loops may include a hinging mechanism such as a spring hinge, and lockable sliding hinge, or the like that can be actuated to deploy the handles into an open configuration.

[0056] The handle assembly 500 according to any of the embodiments disclosed herein may be removably attached to the stabilizing rod 100. For example, the handle assembly may be adapted and configured to engage one or more attachment features on the stabilizing rod 100. Referring to FIGS. 8A-B, in some embodiments, the handle assembly 500 includes a threaded portion 801 (FIG. 8 A) on an inner surface thereof, and the stabilizing rod 100 includes a corresponding threaded portion 803 (FIG. 8B) on an outer surface thereof. In such embodiments, as illustrated in FIG. 8B, the handle assembly 500 may be slid over the distal end of the stabilizing rod 100 and screwed onto the proximal portion thereof, with the internal threading in the handle assembly 500 engaging with the external threading on the outer surface of the proximal end of the rod. Although shown herein primarily with respect to corresponding threaded portions, as will be appreciated by those skilled in the art, the disclosure is not so limited and includes any other suitable mechanism for attaching the handle assembly 500 to the stabilizing rod 100. Other suitable attachment mechanisms include, but are not limited to, engaging a tongue and groove, one or more retractable pegs and holes, or other snapping mechanism as understood in the art.

[0057] Referring now to FIG. 9, in some embodiments, the stabilizing rod will have a quick release mechanism 901 to separate the ETT from the device. The quick release mechanism includes any suitable mechanism for disengaging the ETT from the stabilizing rod. For example, in some embodiments, the stabilizing rod includes a telescoping feature coupled to an actuating element (c. ., button / lever), such that when the actuating element is actuated the telescoping feature disengages (e.g., pushes) the ETT from the stabilizing rod. Although described herein primarily with respect to a telescoping feature, as will be understood by those skilled in the art, the disclosure is not so limited and expressly includes any other suitable quick release mechanism for disengaging the ETT from the stabilizing rod. Additionally, or alternatively, in some embodiments, the stabilizing rod includes one or more elements for sampling CO2. For example, in some embodiments, the proximal end of the stabilizing rod 100 includes an attachment 903 to sample carbon dioxide (CO2) / check capnometry in real time during use. The attachment 903 may include any suitable attachment for sampling CO2, such as, but not limited to, a direct adapter, a luer lock, or any other suitable attachment. Tn some embodiments, the stabilizing rod includes an electronic feature for sampling CO2 during use.

[0058] The stabilizing rod TOO may be formed from one or more biocompatible materials, such as, but not limited to, metal (e.g., stainless steel, titanium, and the like), plastic (e.g., ABS, polyvinyl chloride, and the like), or combinations thereof. In some embodiments, the stabilizing rod is rigid or partially rigid. For example, the stabilizing rod may be constructed from a semirigid material and may be semi-deformable and also capable of applying a load of up to about 20 pounds-force (~ 89 N). Additionally or alternatively, in some embodiments, the stabilizing rod includes elastic material durability that enables frictionless passage through the lumen of the LMA. In some embodiments, the stabilizing rod is disposable.

[0059] In some embodiments, the stabilizing rod includes a mass of about 1000 g (1 kg) or less. For example, the stabilizing rod may have a mass of up to about 1000 g, up to about 900 g, up to about 800 g, up to about 700 g, up to about 600 g, up to about 500 g, up to about 400 g, up to about 300 g, from about 100 g to about 200 g, from about 200 g to about 300 g, from about 300 g to about 400 g, from about 400 g to about 500 g, from about 500 g to about 600 g, from about 600 g to about 700 g, from about 700 g to about 800 g, from about 800 g to about 900 g, from about 900 g to about 1000 g or 1 kg, or any combination, sub-combination, range, or sub-range thereof. Additionally or alternatively, in some embodiments, the stabilizing rod includes a length selected to hold the ETT in place as the LMA is removed without impeding the videoscope from reaching the carina. For example, in some embodiments, the stabilizing rod includes a length of between about 4 cm and about 20 cm. Although specific ranges of length are discussed herein, as will be appreciated by those skilled in the art, the length of the stabilizing rod will vary depending upon the length of the LMA. Therefore, the disclosure is not limited to the specific length ranges discussed herein and any other length corresponding to that of a selected LMA is expressly contemplated.

[0060] Methods

[0061] Also provided herein are methods for intubating a subject using the stabilizing rods according to one or more of the embodiments described herein. In some embodiments, the stabilizing rod enables and / or stabilizes the exchange of an LMA with an ETT under direct visualization e.g., through any suitable videoscope). The subject may be an adult patient or a pediatric patient. The patient may also be a patient with a difficult airway as assessed by a medical professional.

[0062] In some embodiments, the method includes inserting a supra-glottic airway, ventilating the subject, inserting a videoscope with an ETT, directing the vi descope into the subject’s airway, advancing the ETT, and removing the supra-glottic airway. For example, referring to FIGS. 2A-C, in some embodiments, the method includes first inserting a LMA into the subject’s oropharynx and confirming ventilation. In some embodiments, the LMA is placed with its cuffed end within the subject’s oro-hypopharynx. The LMA may include an adult LMA or a pediatric LMA. The LMA may include one or more sizes selected from a number 2, 2.5, 3, 4, 5 LMA, or other suitable number as needed to best fit the subject in need thereof.

[0063] After inserting the LMA, the method may include inserting an ETT into the LMA using the stabilizing rod according to any of the embodiments disclosed herein. For example, in some embodiments, the ETT is engaged with the distal end of the stabilizing rod, and then the stabilizing rod and the engaged ETT are inserted into the LMA. A sterile lubricant gel may be applied to the distal end of the endotracheal tube and its cuff before being inserted into the LMA. Additionally or alternatively, in some embodiments, the ETT adaptor piece is removed before inserting the ETT into the LMA. The ETT adaptor piece may be reconnected to the ETT at any time for ventilation if needed. The ETT may include an ETT sized for an adult subject and / or an ETT sized for a pediatric subject. The ETT tube may include one or more standard number ETT. For example the ETT may be selected from a number 4, 4.5, 5, 5.5, 6, 7, or 8 ETT. Additionally, or alternatively, in some embodiments, ventilation and / or oxygenation can be achieved using the stabilizing rod and engaged ETT by direct attachment to the anesthesia circuit, bag-mask ventilator bag or other jet ventilator by attaching to the universal adapter on the stabilizing rod.

[0064] In some embodiments, the stabilizing rod is loaded onto a videoscope. Additionally, or alternatively, in some embodiments, the proximal end may be secured to the videoscope using a clip-on or friction-based element to mount onto a videoscope such that the device with the engaged ETT remains securely fixed. The stabilizing rod 100 may be loaded by passing the videoscope through the hollow bore of the stabilizing rod. In some embodiments, loading the stabilizing rod 100 onto the videoscope includes mounting the proximal end of the stabilizing rod to the videoscope. Once the stabilizing rod is loaded onto the videoscope, the stabilizing rod and / or ETT is then passed through the LMA and into the trachea under direct videoscopic guidance. For example, in some embodiments, the stabilizing rod / ETT is inserted through the LMA until the subject’s vocal cords are visualized with the videoscope. Alternatively, in some embodiments, the ETT and / or videoscope is advanced past the vocal cords until the carina is visualized. In some embodiments, one skilled in the art such an anesthesiologist, a nurse anesthetist, or the like, may confirm that the distal end of the ETT is well positioned in the trachea and above the carina. As will be appreciated by those skilled in the art, the ETT may be engaged with the stabilizing rod before or after the stabilizing rod is loaded onto the videoscope.

[0065] In some embodiments, following positioning of the ETT, the method includes proximally withdrawing the LMA. In such embodiments, the stabilizing rod may be used to maintain the ETT positioning as the LMA is removed (e.g., from its supraglottic position). In some embodiments, the videoscope may be connected to an oxygen source to transiently oxygenate the patient if needed at any time (e.g., via passive apneic oxygenation and / or for spontaneous breathing patients). In some embodiments, the videoscope may be connected to a suction source to transiently suction the patient if needed at any time. Additionally or alternatively, the method may include removing the videoscope while maintaining the position of the endotracheal tube. For example, the videoscope may be dismounted from the stabilizing rod and then withdrawn from the stabilizing rod and ETT while the stabilizing rod is used to maintain the position of the ETT. In some embodiments, the subject may be transiently oxygenate and or ventilate by connecting the proximal end of the stabilizing rod to a ventilator, (in some cases, the ETT may be advanced into the proximal trachea and while still engaged with the device, can be used to provide oxygenation or ventilation prior to removing the LMA). In some embodiments a pilot balloon on the ETT may be inflated, if needed once it is below the vocal cords (as occurs in the prior example in which the ETT is within the proximal trachea). In some embodiments, the subject may be ventilated through the stabilizing rod and the endotracheal tube. For example, a positive-pressure ventilation device may be coupled to the proximal end of the stabilizing rod 100. The positive-pressure ventilation device may include one or more of a bag-valve mask device, a BiPap device, or other suitable device as understood in the art. Alternatively, in some embodiments, the stabilizing rod is also removed. For example, the LMA, stabilizing rod, and videoscope may be removed while the endotracheal tube remains in-situ. In some embodiments, the LMA, stabilizing rod, and videoscope are removed together, in one motion. At any point during placement of the stabilizing rod / ETT, transient oxygenation, ventilation, and / or removal of any of the elements above, the method may include sampling CO2 from the subject using the attachment 903 according to any of the embodiments disclosed herein. Additionally, or alternatively, whenever disengagement of the stabilizing rod from the ETT is desired, the method may include utilizing the quick release 901 according to any of the embodiments disclosed herein.

[0066] In some embodiments, the method further includes confirming placement of ETT. For example, the placement of the ETT may be confirmed by ventilating the subject and checking end tidal carbon dioxide. Additionally or alternatively, the placement of the ETT may be confirmed by passing a videoscope through endotracheal tube again to visualize.

[0067] In the event that a videoscope is not readily available, or an emergent situation, the intubation may be done as a blind technique with only the ETT, LMA and stabilizing rod. In such embodiments, the LMA is first placed in the patient, followed by the endotracheal tube through the LMA, and the stabilizing rod pushing the ETT in while removing the LMA. This procedure also allows for ventilation and capnometry check when the stabilizing rod is engaged with the ETT.

[0068] The devices and methods disclosed herein enable insertion of an ETT under videoscope vision, while also providing the ability to oxygenate and / or ventilate throughout the procedure. Additionally, the devices and methods disclosed herein facilitate removal of a supra-glottic airway in one swift maneuver. Furthermore, the devices and methods disclosed herein provide a universal adapter and enable universal use with supra-glottic airways. Accordingly, the devices and methods disclosed herein avoid laryngoscopy and / or facilitate insertion of an ETT without neck mobilization.

[0069] EXPERIMENTAL EXAMPLES

[0070] Example 1: Strength Analysis

[0071] The stabilizing rod is subject to a compressive force that is exerted on the loop bottom (for the initial stabilizing rod) and on the semi-circular lip (for the revised stabilizing rod) while its bottom is fully constrained due to holding of the ETT in-place during the LMA removal. This compressive force will cause the stabilizing rod to experience buckling and bending stresses. Therefore, for conservatism, the analysis considers the farthest constrained end of the rod (which is the top of Section 1 as illustrated in FIGS 1 A-1B). This constraint makes the stabilizing rod’s free length be the longest which is the worst scenario for the applied stresses. Therefore, the passing criterion under this farthest constraint guarantees the stabilizing rod safety for upperlevel constraints.

[0072] FIGS. 10A-C show the location where the fixed constraint is applied on the stabilizing rod model.

[0073] In terms of compressive force application, the non-circular shape of the loop in the initial stabilizing rod makes the pressing finger to be placed on three possible locations, as shown in FIG. 11, while the semi-circular lip of the revised stabilizing rod adapter evenly distributes the effect of the pressing finger. Further, the applied force is considered only at one side of the stabilizing rod for conservatism because if the force is balanced over the stabilizing rod sides, the bending stresses will be reduced or even disappear. Therefore, the applied force on one side is the worst scenario on the stabilizing rod.

[0074] FIG. 12 shows the location of the applied force for the revised stabilizing rod. The figure shows the adult stabilizing rod because the pediatric stabilizing rod uses the same rod adapter which is why it is not shown alongside in the figure.

[0075] The applied force is considered as a constant static force.

[0076] For analysis purposes, the assembly interface between stabilizing rod stem and adapter in the revised design is considered as bonded because threading distributes the axial force over the thread length. This consideration is valid because even if a tooth of the thread breaks, the adapter is still fully engaged with the stem which makes total failure at threading is of a negligible probability. Therefore, the threading feature is removed from the model and replaced by a bonded contact for the sake of quick analysis.

[0077] Initial Stabilizing Rod Analysis

[0078] Following a failure during initial pressure testing (FIGS. 13-15), a switch was made to bonded material.

[0079] Revised Pediatric Stabilizing Rod Analysis

[0080] The stabilizing rod for pediatric use was analyzed under 10 lb and 20 lb forces using the ABS material. FIG. 16 shows the von-mises stresses for the 10 Ibf applied on the Rod adapter. It is clearly observed that the stabilizing rod is failure-safe but with a safety factor way less than 2. Therefore, when the 20 Ibf is applied, the stabilizing rod will fail at Section 2 of the stem, as shown in FIG. 17. As such, the ABS material is not suitable for the stem part of the pediatric revised rod. This unsuitability comes from the fact that the size of Section 2 of the stem is small in diameter which makes it highly susceptible to failure. Notice that the adapter experiences negligible stresses which prove that its geometrical features do transfer the compressive force near the stem’s central axis, which does the development of the short moment arm that reduces the experienced bending stresses.

[0081] In view thereof, the stabilizing rod was re-analyzed using stainless steel material for the stem. As shown in FIG. 18, the stabilizing rod is safe from failure under 20 Ibf application when its stem is made of stainless-steel material.

[0082] It is noted that Section 1 of the pediatric stabilizing rod has a wall thickness of 0.85 mm, which is a thin Section that can be easily broken when made from ABS if being bent while inside the ETT top part. Therefore, making the stem of the pediatric stabilizing rod from stainless steel is recommended to prevent Section 2 failure as well as to strengthen Section 1 in case it experiences accidental lateral load.

[0083] Revised Adult Stabilizing Rod Analysis

[0084] Since the stem of the pediatric stabilizing rod is thinner than that for the adult stabilizing rod, the passing criterion of the pediatric stabilizing rod ensures the safety for the adult stabilizing rod as well. Therefore, the adult stabilizing rod was not further analyzed, as it is assured to pass when its stem is made of stainless steel.

[0085] Example 2: Videoscopic-Assisted Endotracheal Rod for Endotracheal Intubation Through a Supraglottic Airway in Patients with Difficult Intubation: A Clinical Device Study

[0086] Tracheal intubation is performed in many settings (e.g., emergency and operating room, and intensive care units). Difficulty with intubation may be known or anticipated in the setting of prior difficulty or in the presence of signs associated with difficulty (e.g., poor mouth opening, short thyromental distance). Difficult tracheal intubation may be unanticipated and may occur in patients without signs suggestive of difficulty.

[0087] Despite widespread availability of airway adjuncts to facilitate intubation (e.g., flexible and rigid video-scopes), failed or traumatic intubations frequently occur and are a common primary damaging event leading to malpractice claims. Complications stemming from failure to oxygenate and ventilate are a major cause of morbidity and mortality in children and adults and a preponderance of malpractice claims. The difficult airway algorithms for pediatrics and adults suggest the use of a supraglottic airway (SGA) after failed attempts at intubation. While useful as a rescue device, definitive airway securement with an endotracheal tube (ETT) and removal of the SGA is generally required.

[0088] Current marketed solutions include placement of an SGA followed by exchange for an ETT through the SGA via the use of an airway exchange catheter or use of an intubating SGA. Current methods can be limited by size restrictions (e.g., limited to sizes 3-5), inability to perform exchange under vision (i.e., ETT advancement performed blindly) or provide oxygenation, or requires the use of a potentially traumatic catheter in the airway. Additionally, the SGA handle may not be suitable for patients with potential neck instability. Airway exchange catheter generally have a lumen for passive oxygenation but do not allow for visualization during ETT placement and have an inherent risk of injury (e.g., tracheobronchial injury, pneumothorax, damage to vocal cords) as well as the inability to pass the ETT over the catheter. Other techniques described include using an uncuffed ETT, laryngeal forceps or other pushing devices to remove the SGA as well as the use of the Air-Q intubating laryngeal airway all requiring advanced skills and familiarity with piecing specific equipment together. Analysis from the PeDI airway registry identified a first-attempt success rate for intubation via an SGA using the videoscope to be 67% based on current techniques. This suggests that alternative approaches to intubation through an SGA are warranted.

[0089] The videoscope assisted endotracheal rod (FASTER) described herein allows for ETT placement through an SGA under vision while maintaining the ability to provide oxygenation via a videoscope as well as the ability to provide ventilation via the attached ETT during the intubation should desaturation occur (FIG. 19). The following feasibility study was designed to test the efficacy and safety of the FASTER device in patients with known difficult airway. The primary aim was the success rate at endotracheal intubation using the FASTER device in patients with difficult airway. Secondary aims include identifying the first attempt success rate, time to intubation, and incidence of adverse events.

[0090] Methods

[0091] Inclusion criteria were subjects that required endotracheal intubation and had previously known difficult airway. Difficult intubation was defined according to the criteria used by the PeDI airway registry to define difficulty. Exclusion criteria were, previous airway management not identified as difficult, procedure not requiring endotracheal intubation.

[0092] Patients were identified for inclusion based on having been flagged as “difficult intubation” in the electronic medical record on a previous encounter and reviewed to ensure they fell within the inclusion criteria. Complications were defined according to definitions used by the PeDI airway registry and included minor airway trauma (dental or lip damage), oro-pharyngeal bleeding, arrhythmia, bronchospasm, epistaxis, esophageal intubation, hypoxemia, laryngospasm, and emesis. Hypoxemia was defined as a 10% decrease from pre-intubation oxygen saturation sustained for more than 45s. Postoperative sore throat, hoarseness, and accidental extubation during removal of the SGA were also recorded.

[0093] Ease of mask ventilation, use of adjuncts (oro-pharyngeal airway), 2-handed mask ventilation, number of intubation attempts (number of times the ETT and device were advanced into the airway), number of times the scope was placed in the airway, number of times the device was used to ventilate, lowest oxygen saturation during attempt, use of oxygen on the videoscope were recorded. Time to intubation (TTI) was defined as the time from the disconnect of the circuit from SGA to the documentation of ETCO2. The SGA, ETT, and videoscope size and brand were recorded.

[0094] The device is fitted with an appropriately sized ETT and loaded onto the videoscope. Once the SGA is in place, the videoscope is inserted and guided into the airway (oxygen can be given via the working channel if needed). Once at the trachea, the device is used to advance the ETT into the airway. The scope can be used to check the ETT position in the airway. The device is disconnected from the ETT and removed. The provider then grasps the ETT in the oropharynx and removes the SGA. The adapter is attached, and ventilation ensues. The videoscope can be removed to allow for ventilation at any point including when the ETT is within the SGA.

[0095] All intubations were video recorded to allow for calculation of intubation times. Sample size was 20 patients. Data was reported as absolute values for intubation attempts. Continuous variables are reported with means and standard deviations. Categorical variables are reported as ranges.

[0096] Results

[0097] Twenty patients were enrolled. The median [IQR] number of previous intubation attempts was 3 [2-3] attempts with 5 (25%) patients labeled as difficult mask ventilation during the prior encounter. The median (IQR) number of attempts to intubate using the device described herein was 1 (1-1). The mean (standard deviation [SD]) TTI was 67 (13) seconds. The mean (SD) time from which the FASTER device was used to advance the ETT until the documentation of ETCO2 waveform was 43 (11) seconds.

[0098] Discussion

[0099] The FASTER device described herein combines the techniques of intubating through an SGA, use of a videoscope, and airway exchange into one method. The FASTER device provides a mechanism for intubation through an SGA under direct vision with a videoscope while maintaining the ability to provide oxygenation. The FASTER device allows for the ability to provide ventilation via the attached ETT during the intubation should desaturation occur. The intubation is performed under vision with the videoscope during which oxygen can be provided using the working channel of the scope. The videoscope can be removed at any time to provide ventilation via the device’s adapter with the ETT fully or partially in the airway or while still in the SGA.

[0100] Successful intubations using the FASTER device were accomplished in 1 attempt and without laryngoscopy in contrast with a median (IQR) of 3 [2-3] attempts on previous encounters for patients in this cohort. In this cohort, during previous encounters, 12 patients required 3 prior attempts and 2 patients required 4 attempts. This is of obvious benefit as the risk for failed airway and the creation of airway trauma increases with the number of attempts at intubation.

[0101] The study described in this Example identifies the FASTER device to be capable for the intubation of children and adolescents with difficult airways. The device provides several advantages including the ability to perform intubation under visualization, use of passive oxygenation, avoidance of laryngoscopy, and movement of the cervical spine. Lastly, the FASTER device provides the ability to ventilate during airway management potentially avoiding the need to abandon an attempt.

[0102] EQUIVALENTS

[0103] Although preferred embodiments of the invention have been described using specific terms, such description is for illustrative purposes only, and it is to be understood that changes and variations may be made without departing from the spirit or scope of the following claims. INCORPORATION BY REFERENCE

[0104] The entire contents of all patents, published patent applications, and other references cited herein are hereby expressly incorporated herein in their entireties by reference.

Claims

CLAIMS1. A stabilizing rod comprising: a distal end comprising at least one section having a reduced outer diameter as compared to another more proximal section; a proximal end adapted and configured for selective engagement with at least one of a videoscope and a positive-pressure ventilation device; a largest outer diameter adapted and configured for passing through an inner diameter of a laryngeal mask airway (LMA); and a hollow bore extending between the distal end and the proximal end, the hollow bore being adapted and configured to receive a portion of the videoscope therein.

2. The stabilizing rod of claim 1, wherein the stabilizing rod is rigid or partially rigid.

3. The stabilizing rod of claim 1, wherein the stabilizing rod is fabricated from one or more selected from the group consisting of metal and plastic.

4. The stabilizing rod of claim 1, wherein the stabilizing rod has a mass of 1,000 g or less.

5. The stabilizing rod of claim 1, wherein the stabilizing rod has a length between 4 cm and20 cm.

6. The stabilizing rod of claim 1, where the stabilizing rod can withstand at least 20 Ibf of applied force.

7. The stabilizing rod of claim 1, wherein the at least one section having a reduced outer diameter is adapted and configured to engage with an endotracheal tube (ETT).

8. The stabilizing rod of claim 7, wherein the reduced outer diameter is further adapted and configured to form a fluid tight seal with the ETT.

9. The stabilizing rod of claim 1, wherein the at least one section having a reduced outer diameter comprises a plurality of proximally ascending outer diameters and shoulders adapted and configured to engage with an inner diameter of a variety of endotracheal tubes (ETTs).

10. The stabilizing rod of claim 9, wherein each outer diameter is adapted and configured to form a fluid tight seal with one or more particular ETT sizes.

11. The stabilizing rod of claim 1, further comprising a quick release feature, the quick release feature adapted and configured to disengage the stabilizing rod from an endotracheal tube (ETT).

12. The stabilizing rod of claim 11, wherein the quick release feature comprises a telescoping element coupled to an actuating element, the telescoping element being adapted and configured to disengage the ETT from the distal end of the stabilizing rod when the actuating element is actuated.

13. The stabilizing rod of claim 1, further comprising an attachment port for sampling CO2.

14. The stabilizing rod of claim 1, wherein the proximal end further comprises a handle, the handle being adapted and configured to grasp, and maintain the position of, the stabilizing rod during use.

15. The stabilizing rod of claim 14, wherein the handle comprises one or more selected from: latching loops and gripped handles.

16. A method of placing an endotracheal tube in a subject, the method comprising: placing a laryngeal mask airway (LMA) with its cuffed end within the subject’s oro- hypopharynx; engaging an endotracheal tube (ETT) with a distal end of the stabilizing rod of claim 1; loading the stabilizing rod onto a videoscope; inserting the ETT into the LMA; and guiding positioning of the ETT with the videoscope.

17. The method of claim 16, wherein the loading of the stabilizing rod onto the videoscope includes passing a portion of the videoscope through the hollow bore of the stabilizing rod.

18. The method of claim 17, wherein the loading of the stabilizing rod onto the videoscope further includes passing a portion of the videoscope through the ETT.

19. The method of claim 16, wherein guiding positioning of the ETT with the videoscope includes advancing the ETT through the lumen of the LMA until the subject’s vocal cords and trachea are observed through the videoscope.

20. The method of claim 16, further comprising proximally withdrawing the LMA while maintaining a position of the ETT and videoscope with the stabilizing rod.

21. The method of claim 20, further comprising: unloading the stabilizing rod from the videoscope; and withdrawing the videoscope while maintaining a position of the ETT with the stabilizing rod.

22. The method of claim 21, further comprising removing the stabilizing rod and withdrawing the LMA;23. The method of claim 16, further comprising confirming placement of the ETT.

24. The method of claim 23, wherein confirming the placement of the endotracheal tube includes ventilating and checking end tidal carbon dioxide, passing the videoscope through endotracheal tube again to visualize, or a combination thereof.

25. The method of claim 16, further comprising: coupling a positive-pressure ventilation device to the proximal end of the stabilizing rod; and ventilating the subject through the stabilizing rod and the endotracheal tube.

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