Patent Description:
<CIT> discloses a sensor for remote monitoring of a closing action of a human sphincter muscle having a micro-fabricated electrode array formed on a flexible substrate and which is in use deformed by the action of a sphincter muscle. The substrate encircles a core electrode and the variations in capacitance with the electrodes is sensed to produce an electrical data output. A multiplexed RF link to an external module allows monitoring of the output of the sensor.

<CIT> discloses a tube for an electromyogram detection type airway intubation based on a position-variable type detector. The tube comprises a tube body, an electrode detector, and a connection conducting wire.

<CIT> discloses a laryngoscope equipped with a dynamometer in order to be able to measure and record a force expended per unit time by an anesthetist during the vacating and keeping unobstructed of a path in the oral and pharyngeal cavity for the introduction of a tube into the trachea. The dynamometer comprises pressure elements arranged in a spatula contact surface and, respectively, in the proximity of a spatula joint.

<NPL>, discloses a monitoring system comprising an electromyography intubation probe. The probe is a PVC endotracheal tube, with low-pressure balloon and <NUM> pairs of <NUM>-cm recording electrodes positioned in contact with the vocal folds.

An exemplary method, not according to the invention, of operating an intraoperative nerve monitoring system for monitoring nerve activity within a trachea of a patient is provided. The intraoperative nerve monitoring system includes a console having a controller and an output device and an endotracheal (ET) tube assembly. The ET tube assembly includes an ET tube having an outer circumferential surface, a surface electrode wrapped about a portion of the outer circumferential surface of the ET tube, and a pressure sensor assembly coupled to the outer circumferential surface of the ET tube. The method of operating the intraoperative nerve monitoring system includes steps of inserting the ET tube within the trachea of the patient; sensing, with the pressure sensor assembly, an amount of pressure between the surface electrode and a target tissue; determining, with the controller, whether the amount of pressure exceeds a pressure threshold; outputting, with the output device, a first indicator based on whether the amount of pressure exceeds the pressure threshold to facilitate proper placement of the ET tube in the trachea; monitoring, with the surface electrode, nerve activity within the trachea while the ET tube is inserted within the trachea; and outputting, with the output device, a second indicator based on the nerve activity.

An intraoperative nerve monitoring system for monitoring nerve activity within a trachea of a patient is provided in accordance with the claims.

Referring now to the drawings, exemplary illustrations are shown in detail. Although the drawings represent examples, the drawings are not necessarily to scale and certain features may be exaggerated or schematic in form to better illustrate and explain a particular aspect of an illustrative example. Any one or more of these aspects can be used alone or in combination with one another. Further, the exemplary illustrations described herein are not intended to be exhaustive or otherwise limiting or restricting to the precise form and configuration shown in the drawings and disclosed in the following detailed description. Exemplary illustrations are described in detail by referring to the drawings as follows:.

Referring to <FIG> and <FIG>, an intraoperative nerve monitoring system <NUM> for monitoring nerve activity within a trachea <NUM> of a patient is shown. Referring to <FIG>, the intraoperative nerve monitoring system <NUM> includes an endotracheal (ET) tube assembly <NUM>, which includes an endotracheal (ET) tube <NUM>, a surface electrode <NUM>, and a pressure sensor assembly <NUM>. Additionally, the intraoperative nerve monitoring system <NUM> includes a console <NUM>, which includes a controller <NUM> and an output device <NUM>.

As shown in <FIG>, the ET tube <NUM> of the ET tube assembly <NUM> includes a length L. Referring to <FIG>, the ET tube <NUM> is configured to be at least partially inserted within a trachea <NUM> of a patient. As such, the length L is sufficient for insertion within the trachea <NUM> of the patient. Additionally, referring to <FIG>, the ET tube <NUM> may be inserted within the trachea <NUM> such that the ET tube <NUM> is rotatable clockwise and counterclockwise and slidable proximally and distally within the trachea <NUM>, as illustrated by the directional arrows A1, A2, A3, and A4, respectively.

Furthermore, the ET tube <NUM> may comprise, consist essentially of, or consist of, a compliant material, such as a polymer. As such, the ET tube <NUM> may comply with a shape of the trachea, allowing the ET tube <NUM> to be at least partially inserted within the trachea <NUM>. The compliant material may comprise one or more polymers. For example, in some instances, the compliant material is selected from elastomers, thermoplastics, thermoplastic elastomers, and combinations thereof.

Also shown in <FIG>, the ET tube <NUM> of the ET tube assembly <NUM> includes an outer circumferential surface S. In <FIG>, the surface electrode <NUM> is wrapped about a portion of the outer circumferential surface S of the ET tube <NUM> and the pressure sensor assembly <NUM> is coupled to the outer circumferential surface S. While the surface electrode <NUM> is shown as being wrapped helically to the ET tube <NUM>, the surface electrode <NUM> may alternatively be wrapped in other manners. Alternately, the surface electrode <NUM> and the pressure sensor assembly <NUM> may be coupled to the outer circumferential surface S without any specific wrapping arrangement.

The surface electrode <NUM> is configured to monitor nerve activity when the ET tube <NUM> is at least partially inserted within the trachea <NUM>. The surface electrode <NUM> is also configured to output a nerve signal <NUM> corresponding to the monitored nerve activity, as shown in <FIG>. In some instances, the nerve signal <NUM> may be a voltage signal, wherein the voltage of the nerve signal <NUM> corresponds to the nerve activity.

Referring to <FIG> and <FIG>, the ET tube <NUM> may be inserted within the trachea <NUM> such that the surface electrode <NUM> contacts a target tissue <NUM>. In <FIG> and <FIG>, the target tissue <NUM> is a laryngeal muscle (and may be referred to herein as laryngeal muscle <NUM>) and the surface electrode <NUM> is configured to monitor the nerve activity of the vagus nerve <NUM> and/or the laryngeal nerve <NUM>. However, in other instances, the target tissue <NUM> may be a tissue other than the laryngeal muscle <NUM> and the surface electrode <NUM> may be configured to monitor the nerve activity of a nerve other than the vagus nerve <NUM> and/or the laryngeal nerve <NUM>. Furthermore, the surface electrode <NUM> may be configured to monitor the nerve activity of any number of nerves.

The surface electrode <NUM> may be any suitable device for monitoring the nerve activity. For example, the surface electrode <NUM> may include a plurality of electrode contacts configured to sense electromyography (EMG) signals to monitor the nerve activity.

The surface electrode <NUM> may be coupled to the outer circumferential surface S using any suitable means. For example, in <FIG>, the surface electrode <NUM> is wrapped about a portion of the outer circumferential surface S of the ET tube <NUM>. In another instance, the surface electrode <NUM> may be affixed to the ET tube <NUM> using an adhesive. In yet another instance, the surface electrode <NUM> may be integral to the outer circumferential surface S of the ET tube <NUM>.

The pressure sensor assembly <NUM> is configured to sense an amount of pressure between the surface electrode <NUM> and the target tissue <NUM>. As shown in <FIG>, the pressure sensor assembly <NUM> is also configured to output a pressure signal <NUM> corresponding to the sensed amount of pressure. In some instances, the pressure signal <NUM> may be a voltage signal, wherein the voltage of the pressure signal <NUM> corresponds to the sensed amount of pressure.

According to the invention, the pressure sensor assembly <NUM> is coupled to the outer circumferential surface S of the ET tube <NUM> using any suitable means. For example, in <FIG>, the pressure sensor assembly <NUM> is coupled to surface electrode <NUM>, which is wrapped about a portion of the outer circumferential surface S. An example coupling of the pressure sensor assembly <NUM> to the surface electrode <NUM> is illustrated in <FIG>. As shown, the ET tube assembly <NUM> includes two substrate layers <NUM> and an adhesive layer <NUM>, which are configured to couple the pressure sensor assembly <NUM> to the surface electrode <NUM>. In various instances, the pressure sensor assembly <NUM> may be coupled to the surface electrode <NUM> using any suitable means. For example, in some instances, the ET tube assembly <NUM> may include a greater or lesser number of substrate layers <NUM> and adhesive layers <NUM> for coupling the pressure sensor assembly <NUM> to the surface electrode <NUM>. In still other instances, the ET tube assembly <NUM> may omit the substrate layers <NUM> and/or the adhesive layers <NUM>. Furthermore, in some instances, the pressure sensor assembly <NUM> may be directly coupled to the outer portion of the outer circumferential surface S without being coupled to the surface electrode <NUM>. For example, the pressure sensor assembly <NUM> may be directly affixed to the outer circumferential surface S using an adhesive. In certain instances, the pressure sensor assembly <NUM> may be positioned such that the pressure sensor assembly <NUM> is closer to the lumen of the ET tube <NUM> than to the surface electrode <NUM>.

The pressure sensor assembly <NUM> may include a plurality of pressure sensors, such as two or more pressure sensors. For example, in <FIG>, the pressure sensor assembly <NUM> includes four pressure sensors 18a, 18b, 18c, 18d. The pressure sensor assembly <NUM> may be configured to sense the amount of pressure between the surface electrode <NUM> and the target tissue <NUM> by sensing an amount of pressure with each of the four pressure sensors 18a, 18b, 18c, 18d. For instance, each pressure sensor 18a, 18b, 18c, 18d may be configured to sense an amount of pressure between the surface electrode <NUM> and the target tissue <NUM> at a region on the outer circumferential surface S. For example, referring to <FIG>, the pressure sensors 18a, 18b, 18c, and 18d are configured, according to the invention, to sense the amount of pressure between the surface electrode <NUM> and the target tissue <NUM> at regions Ra, Rb, Rc, Rd, respectively. As such, the pressure sensor assembly <NUM> is able to sense the amount of pressure between the surface electrode <NUM> and the target tissue <NUM> by sensing the amount of pressure at the regions Ra, Rb, Rc, Rd.

As shown in <FIG>, the regions Ra, Rb, Rc, and Rd are divided by dividers D1 and D2 such that regions Ra and Rb are generally above the regions Rc and Rd. Furthermore, the regions Ra and Rc are angularly offset from the regions Rb and Rd. In other instances, the regions Ra, Rb, Rc, and Rd may be arranged using alternative means. For example, in some instances, the regions Ra and Rc may be vertically offset from the regions Rb and Rd. Similarly, the regions Ra and Rb may be horizontally offset from the regions Rc and Rd. In other instances, the regions Ra, Rb, Rc, and Rd may be arranged vertically along the outer circumferential surface S such that the region Ra is generally above the region Rb, which is generally above the region Rc, which is generally above the region Rd. Similarly, the regions Ra, Rb, Rc, and Rd may be arranged horizontally along the outer circumferential surface S. In still other instances, the regions Ra, Rb, Rc, and Rd may be arranged such that a different number of regions are generally above or angularly offset from one another. For instance, region Ra may be generally above the regions Rb, Rc, and Rd, which may be arranged horizontally. Similarly, region Ra may be angularly offset from regions Rb, Rc, and Rd, which may be arranged vertically. Additionally, in some instances, such as the instance of <FIG>, the regions may be separate, distinct regions on the outer circumferential surface S. However, in other instances, the regions on the outer circumferential surface S may overlap. Furthermore, the regions may be of any suitable size and the sizes of each region may be independent from one another.

Additionally, while the regions are described herein as regions on the outer circumferential surface S, the regions may be arranged such that the regions correspond to and/or include regions of the surface electrode <NUM>. For example, the regions Ra, Rb, Rc, and Rd are regions on the outer circumferential surface S, but may also be described herein as a top-left, a top-right, a bottom-left, and a bottom-right region of the surface electrode <NUM>. As such, while the pressure sensor assembly <NUM> is described as being configured to determine the amount of pressure between the surface electrode <NUM> and the target tissue <NUM> at a plurality of regions on the outer circumferential surface S, the pressure sensor assembly <NUM> may also be described as being configured to determine the amount of pressure between a plurality of regions of the surface electrode <NUM> and the target tissue <NUM>.

The number of pressure sensors included by the pressure sensor assembly <NUM> and the number of regions may vary. For example, the number of pressure sensors and the number of regions may not be equivalent to four. Furthermore, the number of pressure sensors and the number of regions may not be equivalent to one another. For example, referring to <FIG>, the pressure sensor assembly <NUM> need not have four distinct pressure sensors 18a, 18b, 18c, 18d, so long as the pressure sensor assembly <NUM> is able to distinguish between the amounts of pressure in the four regions Ra, Rb, Rc, and Rd. In such an instance, the pressure sensor assembly <NUM> may include three distinct pressure sensors for sensing the amounts of pressure in the regions Ra, Rb, Rc, and Rd. Similarly, the pressure sensor assembly <NUM> may include a number of distinct pressure sensors greater than the number of regions. For instance, the pressure sensor assembly may include eight distinct pressure sensors such that the amount of pressure in each of the four regions Ra, Rb, Rc, and Rd is sensed by two of the pressure sensors for added resolution. As such, the number of regions and/or pressure sensors is not particularly limited. In addition, the positioning of the sensors relative to the regions and the arrangement of the sensors generally is not limited.

The pressure sensor assembly <NUM> may include any suitable sensor for sensing the amount of pressure. For example, in <FIG>, the pressure sensors 18a, 18b, 18c, 18d are illustrated as resistive pressure sensors that include two sections separated by the adhesive layer <NUM>. In some instances, the pressure sensors 18a, 18b, 18c, 18d may be like the pressure sensors shown in <CIT>, entitled, "Pressure Sensor", the disclosure of which is hereby incorporated by reference in its entirety. In other instances, the pressure sensor assembly <NUM> may include a strain gauge, a capacitive sensor, or any other sensor suitable for sensing the amount of pressure. For example, the pressure sensor assembly <NUM> may include one or more layers of pressure sensitive ink embedded between flexible substrate layers, such as the substrate layers <NUM>.

Referring to <FIG> and <FIG>, the intraoperative nerve monitoring system <NUM> also includes a console <NUM>. Also shown, the console <NUM> may include a controller <NUM>, which is configured to receive the nerve signal <NUM> and the pressure signal <NUM> and output an output signal <NUM> based on the nerve signal <NUM> and the pressure signal <NUM>.

As shown in <FIG>, the controller <NUM> may include a processor <NUM> and a memory <NUM>. The processor <NUM> may be any processor suitable for processing data. For example, the processor <NUM> may be a processor typically found in a desktop computer. Similarly, the memory <NUM> may be any memory suitable for storage of data and computer-readable instructions. For example, the memory <NUM> may be a local memory, an external memory, or a cloud-based memory. The memory <NUM> may also be a random access memory (RAM), non-volatile RAM (NVRAM), flash memory, or any other suitable form of memory. In some instances, the processor <NUM> and the memory <NUM> may be configured to process the nerve signal <NUM> and the pressure signal <NUM> and output a corresponding output signal <NUM>.

As previously stated, the controller <NUM> is configured to receive the nerve signal <NUM> and the pressure signal <NUM> from the surface electrode <NUM> and the pressure sensor assembly <NUM>, respectively. In <FIG>, the console <NUM> may be coupled to the ET tube assembly <NUM> via the connector <NUM> such that the controller <NUM> may receive the nerve signal <NUM> and the pressure signal <NUM> from the surface electrode <NUM> and the pressure sensor assembly <NUM>, respectively, via the connector <NUM>. However, it should be noted that the console <NUM> may be coupled to the ET tube assembly <NUM> using wireless transceivers.

Also shown in <FIG> and <FIG>, the console <NUM> may also include an output device <NUM>. The output device <NUM> is configured to receive the output signal <NUM> from the controller <NUM> and output a first indicator <NUM> and a second indicator <NUM> based on the output signal <NUM>. The first indicator <NUM> is configured to facilitate proper placement of the ET tube <NUM> in the trachea <NUM> based on the amount of pressure between the surface electrode <NUM> and the target tissue <NUM>, and the second indicator <NUM> is indicative of the nerve activity monitored by the surface electrode <NUM>. The first indicator <NUM> and the second indicator <NUM> may include a visual indicator and/or an audible indicator. As such, the output device <NUM> may include a screen <NUM> for displaying a visual indicator and a speaker <NUM> for outputting an audible indicator, as shown in <FIG>.

In <FIG>, five examples of the first indicator <NUM> are shown. In each example, the first indicator <NUM> includes a numerical indicator <NUM>, which includes at least one number corresponding to the amount of pressure between the surface electrode <NUM> and the target tissue <NUM>. As previously discussed, this amount of pressure is sensed by the pressure sensor assembly <NUM>. As will be described herein, the numerical indicator <NUM> facilitates proper placement of the ET tube <NUM> in the trachea <NUM> by outputting the at least one number.

The at least one number output by the numerical indicator <NUM> corresponds to the amount of pressure between the surface electrode <NUM> and the target tissue <NUM>. In some instances, the at least one number may output the amount of pressure sensed by the pressure sensor assembly <NUM> using any suitable unit. For instance, the numerical indicator <NUM> may output the at least one number corresponding to the amount of pressure sensed by the pressure sensor assembly <NUM> in pascals, volts, pounds per square inch, bars, etc. The at least one number may also be a scaled factor of the amount of pressure sensed by the pressure sensor assembly <NUM> and may be unit-less. For example, in <FIG>, the numbers 51a, 51b are unit-less and may be any whole number between "<NUM>" and "<NUM>", inclusive. However, in other instances, the at least one number may be any rational number between any suitable range. Furthermore, each of the numbers 51a, 51b in <FIG> are scaled representations of a range of pressures. For example, each of the numbers from "<NUM>" to "<NUM>" corresponds to an increasing range of pressures. However, in other instances, the at least one number may correspond to a decreasing range of pressures.

Additionally, as shown in <FIG>, the first indicator <NUM> may include a diagram <NUM> of the ET tube assembly <NUM> within the trachea <NUM>, wherein the surface electrode <NUM> is illustrated as contacting the target tissue <NUM>. In some instances, the diagram <NUM> of the ET tube assembly <NUM> within the trachea <NUM> may be omitted from the first indicator <NUM>.

In <FIG>, the numerical indicator <NUM> includes a number corresponding to the amount of pressure between the surface electrode <NUM> and the target tissue <NUM> at two regions of the outer circumferential surface S, a first region 16a and a second region 16b, which are labeled on the diagram <NUM>. In such an instance, the pressure sensor assembly <NUM> may be configured to sense the amount of pressure between the surface electrode <NUM> and the target tissue <NUM> at the first region 16a and the second region 16b. The first region 16a and the second region 16b may correspond to the previously described regions Ra, Rb, Rc, and Rd, which are shown in <FIG>. For instance, in <FIG>, the first region 16a includes the regions Ra and Rb and the second region 16b includes the regions Rc and Rd. In such instances, the divider D1 from <FIG> may divide the first region 16a and the second region 16b, as shown in the diagram <NUM>. In other instances, the pressure sensor assembly <NUM> may be configured to sense the amount of pressure at regions other than the first and second regions 16a and 16b. Accordingly, in such instances, the first indicator <NUM> may include a number corresponding to the amount of pressure at the regions other than the first and second regions 16a and 16b.

In <FIG>, the numerical indicator <NUM> includes a first number 51a and a second number 51b, which correspond to the amount of pressure between the surface electrode <NUM> and the target tissue <NUM> at the first region 16a and the second region 16b of the outer circumferential surface S, respectively. As shown, the numerical indicator <NUM> may be placed adjacent to the diagram <NUM> of the ET tube assembly <NUM> such the first number 51a is aligned with the first region 16a and the second number 51b is aligned with the second region 16b. Furthermore, the numerical indicator <NUM> is configured to output a "<NUM>", "<NUM>", or "<NUM>" if the amount of pressure sensed at the corresponding region is too high, suggesting that the position of the ET tube <NUM> should be adjusted to decrease the pressure between the region of the outer circumferential surface S and the surface electrode <NUM>. Likewise, the numerical indicator <NUM> is configured to output a "<NUM>", "<NUM>", or "<NUM>" if the amount of pressure sensed at the corresponding region is too low, suggesting that the position of the ET tube <NUM> should be adjusted to increase the pressure between the region of the outer circumferential surface S and the surface electrode <NUM>. As such, by outputting a number corresponding to the amount of pressure between the outer circumferential surface S and the first and second regions 16a and 16b, the first indicator <NUM> is configured to facilitate proper placement of the ET tube <NUM> in the trachea <NUM>.

For example, in <FIG>, one instance where the numerical indicator <NUM> of the first indicator <NUM> facilitates proper placement of the ET tube <NUM> in the trachea <NUM> is shown. As shown, the numerical indicator <NUM> indicates that the amount of pressure between the surface electrode <NUM> and the target tissue <NUM> at the first region 16a is too high by outputting the number "<NUM>" as the first number 51a. Similarly, the numerical indicator <NUM> indicates that the amount of pressure at the second region 16b is too low by outputting the number "<NUM>" as the second number 51b. As such, the numerical indicator <NUM> suggests that the position of the ET tube <NUM> should be adjusted such that the amount of pressure is decreased at the first region 16a and increased at the second region 16b. As previously stated, the ET tube <NUM> may be inserted within the trachea <NUM> such that the ET tube <NUM> is rotatable clockwise and counterclockwise and slidable proximally and distally within the trachea <NUM>, as illustrated by the directional arrows A1, A2, A3, and A4, respectively, in <FIG>. In the example of <FIG>, the numerical indicator <NUM> suggests that the ET tube <NUM> should be urged distally (along the direction of A4) in order to properly position the ET tube <NUM> within the trachea <NUM>. In this way, the amount of pressure between the surface electrode <NUM> and the target tissue <NUM> is decreased at the first region 16a and the amount of pressure between the surface electrode <NUM> and the target tissue <NUM> is increased at the second region 16b.

For example, in <FIG>, one instance where the numerical indicator <NUM> of the first indicator <NUM> facilitates proper placement of the ET tube <NUM> in the trachea <NUM> is shown. As shown, the numerical indicator <NUM> indicates that the amount of pressure between the surface electrode <NUM> and the target tissue <NUM> at the first region 16a is too high by outputting the number "<NUM>" as the first number 51a. In addition, the first region 16a is highlighted in the diagram <NUM> and the first number 51a is highlighted. Similarly, the numerical indicator <NUM> indicates that the amount of pressure at the second region 16b is too low by outputting the number "<NUM>" as the second number 51b. As such, the numerical indicator <NUM> suggests that the position ET tube <NUM> should be adjusted such that the amount of pressure is decreased at the first region 16a and increased at the second region 16b. As previously stated, the ET tube <NUM> may be inserted within the trachea <NUM> such that the ET tube <NUM> is rotatable clockwise and counterclockwise and slidable proximally and distally within the trachea <NUM>, as illustrated by the directional arrows A1, A2, A3, and A4, respectively, in <FIG>. In the example of <FIG>, the numerical indicator <NUM> suggests that the ET tube <NUM> should be urged distally along the direction of A4 in order to properly position the ET tube <NUM> within the trachea <NUM>. In this way, the amount of pressure between the surface electrode <NUM> and the target tissue <NUM> is decreased at the first region 16a and the amount of pressure between the surface electrode <NUM> and the target tissue <NUM> is increased at the second region 16b.

In <FIG>, another instance where the numerical indicator <NUM> of the first indicator <NUM> facilitates proper placement of the ET tube <NUM> in the trachea <NUM> is shown. As shown, the numerical indicator <NUM> indicates that the amount of pressure between the surface electrode <NUM> and the target tissue <NUM> at the first region 16a is too low by outputting the number "<NUM>" as the first number 51a. Similarly, the numerical indicator <NUM> indicates that the amount of pressure at the second region 16b is too high by outputting the number "<NUM>" as the second number 51b. In addition, the second region 16b is highlighted in the diagram <NUM> and the second number 51b is highlighted. As such, the numerical indicator <NUM> suggests that the position of the ET tube <NUM> should be adjusted such that the amount of pressure is increased at the first region 16a and decreased at the second region 16b. In the example of <FIG>, the numerical indicator <NUM> suggests that the ET tube <NUM> should be urged proximally along the direction of A3 in order to properly position the ET tube <NUM> within the trachea <NUM>. In this way, the amount of pressure between the surface electrode <NUM> and the target tissue <NUM> is increased at the first region 16a and the amount of pressure between the surface electrode <NUM> and the target tissue <NUM> is decreased at the second region 16b.

In <FIG>, an instance where the numerical indicator <NUM> of the first indicator <NUM> illustrates that the ET tube <NUM> is properly placed in the trachea <NUM> is shown. As shown, the numerical indicator <NUM> indicates that the amount of pressure at the first and second regions 16a and 16b is within a range of acceptability. As such, both the first region 16a and the second region 16b, which are divided by D1 (shown in the diagram <NUM> of <FIG> for illustrative purposes), are highlighted as shown in diagram <NUM>. The first and second numbers 51a, 51b are also highlighted. As previously stated, each of the numbers 51a, 51b in <FIG> are scaled representations of a range of pressures. Here, the range of pressures may be selected such that the range corresponding to the number "<NUM>" is a range of acceptable pressures.

In <FIG> and <FIG>, two more instances where the numerical indicator <NUM> of the first indicator <NUM> facilitates proper placement of the ET tube <NUM> in the trachea <NUM> are shown. Similar to <FIG> and <FIG>, the numerical indicator <NUM> of <FIG> and <FIG> indicates that the amount of pressure between the surface electrode <NUM> and the target tissue <NUM> is too high or too low at the first and second regions 16a and 16b. However, in <FIG>, the numerical indicator <NUM> outputs a "<NUM>" as the first number 51a and a "<NUM>" as the second number 51b, indicating that the amount of pressure is too high at the first region 16a and too low at the second region 16b. In <FIG>, the numerical indicator <NUM> outputs a "<NUM>" as the first number 51a and a "<NUM>" as the second number 51b, indicating that the amount of pressure is too low at the first region 16a and too high at the second region 16b. As previously stated, each of the numbers 51a, 51b in <FIG> are scaled representations of a range of pressures and each of the numbers from "<NUM>" to "<NUM>" correspond to an increasing range of pressures. In this way, the numerical indicator <NUM> indicates a magnitude by which the amount of pressure between the surface electrode <NUM> and the target tissue <NUM> is too high or too low and a magnitude of the suggested adjustment of the ET tube <NUM>. For context, in some instances, after the output device <NUM> outputs the first indicator <NUM> of <FIG>, the output device <NUM> outputs the first indicator <NUM> of <FIG> as the ET tube <NUM> is urged distally along the direction of A4 before outputting the first indicator <NUM> of <FIG>. Similarly, after the output device <NUM> outputs the first indicator <NUM> of <FIG>, the output device <NUM> may output the first indicator <NUM> of <FIG> as the ET tube <NUM> is urged proximally along the direction of A3 before outputting the first indicator <NUM> of <FIG>.

In <FIG>, five examples of the first indicator <NUM> are shown. In each example, the first indicator <NUM> includes an indication of an adjustment <NUM> to correct the position of the ET tube <NUM> in the trachea <NUM>. The indication of the adjustment <NUM> is based on the amount of pressure between the surface electrode <NUM> and the target tissue <NUM>. Additionally, in <FIG>, the first indicator <NUM> is configured to provide the indication of the adjustment <NUM> based on the amount of pressure between the surface electrode <NUM> and the outer circumferential surface S at a plurality of regions. The plurality of regions may be the previously described regions Ra, Rb, Rc, and Rd. The first region 16a and the second region 16b, labelled in <FIG>, may include the regions Ra and Rb and the regions Rc and Rd, respectively. A third region 16c and a fourth region 16d, labelled in <FIG>, may include the regions Ra and Rc and the regions Rb and Rd, respectively.

Similar to the first indicator <NUM> of <FIG>, the first indicator <NUM> in <FIG> may include a diagram <NUM> of the ET tube assembly <NUM> within the trachea <NUM>, wherein the surface electrode <NUM> is illustrated as contacting the target tissue <NUM>. As previously stated, the diagram <NUM> of the ET tube assembly <NUM> within the trachea <NUM> may be omitted from the first indicator <NUM>.

In <FIG>, the indication of the adjustment <NUM> includes an indication of a clockwise rotation A1 of the ET tube <NUM>, a counterclockwise rotation A2 of the ET tube <NUM>, a proximal sliding A3 of the ET tube <NUM>, and a distal sliding A4 of the ET tube <NUM>. However, in other instances, the indication of the adjustment <NUM> may omit any of the above adjustments. For example, the indications of the adjustments <NUM> in <FIG> only include a proximal sliding A3 of the ET tube <NUM>, and a distal sliding A4 of the ET tube <NUM>. Furthermore, while the indication of the adjustment <NUM> only includes an indication of one of the adjustments A1, A2, A3, and A4 at a time, in other instances, the indication of the adjustment <NUM> may include more than one adjustment A1, A2, A3, and A4. For example, the indication of the adjustment <NUM> may simultaneously include an indication of a clockwise rotation A1 and a distal sliding A4 of the ET tube <NUM>.

<FIG> illustrates an instance of the first indicator <NUM>, where the indication of the adjustment <NUM> includes an indication of a distal sliding A4 of the ET tube <NUM>. As previously stated, the indication of the adjustment <NUM> is based on the amount of pressure between the surface electrode <NUM> and the target tissue <NUM> at a plurality of regions. In <FIG>, the amount of pressure at the first region 16a is determined to be too high and the first region 16a is highlighted in the diagram <NUM>. As such, the indication of the adjustment <NUM> is an indication of the distal sliding A4 of the ET tube <NUM> to decrease the amount of pressure at the first region 16a.

<FIG> illustrates an instance of the first indicator <NUM>, where the indication of the adjustment <NUM> includes an indication of a proximal sliding A3 of the ET tube <NUM>. In <FIG>, the amount of pressure at the second region 16b is determined to be too high and the second region 16b is highlighted in the diagram <NUM>. As such, the indication of the adjustment <NUM> is an indication of the distal sliding A4 of the ET tube <NUM> to decrease the amount of pressure at the second region 16b.

The indications of the adjustments <NUM> in <FIG> include a magnitude indicator <NUM>. Elements of the magnitude indicators <NUM> are labelled in <FIG> and <FIG> for the purposes of explanation. In <FIG>, the magnitude indicator <NUM> includes a partial arrowhead 55a and a strong highlighting 55b of the distal sliding A4 adjustment to indicate a magnitude of the distal sliding A4 of the ET tube <NUM>. In <FIG>, the magnitude indicator <NUM> does not include the partial arrowhead 55a and does not include the strong highlighting 55b. However, the magnitude indicator <NUM> in <FIG> includes a light highlighting 55c of the proximal sliding A3 adjustment. In this way, the magnitude indicator <NUM> indicates a magnitude of the proximal sliding A3 of the ET tube <NUM> that is lesser than the magnitude of the distal sliding A4 of the ET tube <NUM> in <FIG>. In other words, the magnitude indicators <NUM> in <FIG> and <FIG> indicate that the ET tube <NUM> should be urged distally a farther distance in <FIG> than the ET tube <NUM> should be urged proximally in <FIG>.

In <FIG>, an instance of the first indicator <NUM> is shown, where the indication of the adjustment <NUM> illustrates that the ET tube <NUM> is properly placed in the trachea <NUM> and no adjustment is required. In <FIG>, the first region 16a and the second region 16b of the ET tube <NUM>, which are divided by D1 (shown in the diagram <NUM> of <FIG> for illustrative purposes), are highlighted as shown in diagram <NUM>. In addition, the indication of the adjustment <NUM> includes an indication of proper placement <NUM>.

<FIG> and <FIG> illustrate instances of the first indicator <NUM>, where the indication of the adjustment <NUM> includes an indication of a clockwise rotation A1 of the ET tube <NUM> in <FIG> and an indication of a counterclockwise rotation A2 in <FIG>. In <FIG> and <FIG>, the indication of the adjustment <NUM> is based on the amount of pressure at the third region 16c and the fourth region 16d, which are divided by divider D2 (the divider is shown in <FIG> for illustrative purposes). In <FIG>, the amount of pressure at the third region 16c is determined to be too high and the third region 16c is highlighted in the diagram <NUM>. In <FIG>, the amount of pressure at the fourth region 16d is determined to be too high and the fourth region 16d is highlighted in the diagram <NUM>. Furthermore, referring back to <FIG>, where the indication of the adjustment <NUM> illustrates that no adjustment to the ET tube <NUM> is required, the divider D2 is illustrated as bisecting the surface electrode <NUM> vertically. Accordingly, in <FIG> and <FIG>, where the indication of the adjustment <NUM> indicates that the ET tube <NUM> should be rotated clockwise A1 and counterclockwise A2, the divider D2 is horizontally offset. Additionally, the indication of the adjustment <NUM> of <FIG> and <FIG> includes the magnitude indicator <NUM>. As such, the ET tube <NUM> should be rotated clockwise A1 a farther distance in <FIG> than the ET tube <NUM> should be rotated counterclockwise A2 in <FIG>.

In <FIG>, several examples of the first indicator <NUM> are shown. However, in other instances, the first indicator <NUM> may vary. For instance, the first indicator <NUM> may include color-coding, which may include any suitable color. In one such instance, the highlighted regions of the surface electrode <NUM>, as shown in the diagram <NUM>, may be highlighted with a bright red when the amount of pressure at the region is too high and the ET tube <NUM> requires an adjustment. The highlighted regions of the surface electrode <NUM> may be highlighted with a dull green when the ET tube <NUM> is properly placed. Similarly, the numbers 51a, 51b and the adjustments <NUM> in the A1, A2, A3, A4 directions may be highlighted bright red when the ET tube <NUM> requires an adjustment and the numerical indicator <NUM> and the indication of proper placement <NUM> may be highlighted dull green when the ET tube is properly placed. In another instance, elements of the first indicator <NUM>, such as the diagram <NUM>, the numerical indicator <NUM>, and the indicator of the adjustment <NUM> may not be highlighted. In yet another instance, a size and a position of the elements of the first indicator <NUM> may vary.

In some instances, such as the examples of the first indicator <NUM> shown in <FIG>, the first indicator <NUM> may include the numerical indicator <NUM> and the indicator of the adjustment <NUM>. As shown in <FIG>, the numerical indicator <NUM> and the diagram <NUM> indicate that the amount of pressure in the first region 16a is too high. Accordingly, the indication of the adjustment <NUM> indicates that the ET tube <NUM> should be distally urged A4. In <FIG>, the numerical indicator <NUM> and the diagram <NUM> indicate that the amount of pressure in the second region 16b is too high. Accordingly, the indication of the adjustment <NUM> indicates that the ET tube <NUM> should be proximally urged A3. In <FIG>, the numerical indicator <NUM> and the diagram <NUM> indicate that the ET tube <NUM> is properly placed. Accordingly, the indication of the adjustment <NUM> includes the indication of proper placement <NUM>.

In <FIG>, an instance of the second indicator <NUM> is shown, wherein the second indicator <NUM> includes a waveform corresponding to the nerve activity monitored by the surface electrode <NUM>. In the instance of <FIG>, the surface electrode <NUM> is configured to monitor nerve activity of the valgus nerve <NUM> and the laryngeal nerve <NUM> (shown in <FIG>). As such, the second indicator <NUM> in <FIG> includes a waveform 50a corresponding to the monitored activity of the valgus nerve <NUM> and a waveform 50b corresponding to the monitored activity of the laryngeal nerve <NUM>. In instances where the surface electrode <NUM> is configured to monitor nerve activity of a different nerve, the second indicator <NUM> may include a waveform corresponding to the nerve activity of the different nerve. Furthermore, as previously stated, the surface electrode <NUM> may be configured to monitor the nerve activity of any number of nerves. Accordingly, the second indicator <NUM> may include any number of corresponding waveforms.

In <FIG>, an instance of the output device <NUM> is shown, wherein the output device <NUM> is configured to output the first indicator <NUM> and the second indicator <NUM> concurrently. In <FIG>, the output device <NUM> outputs an instance of the first indicator <NUM> where the first indicator <NUM> includes the numerical indicator <NUM> and the indication of the adjustment <NUM>. The output device <NUM> also outputs an instance of the second indicator <NUM>, where the second indicator <NUM> includes the waveform 50a corresponding to the monitored activity of the valgus nerve <NUM> and the waveform 50b corresponding to the monitored activity of the laryngeal nerve <NUM>. In other instances, the output device <NUM> may output any previously described instance of the first indicator <NUM> or any combination thereof. Similarly, the output device <NUM> may concurrently output any previously described instance of the second indicator <NUM> or any combinations thereof.

Referring now to <FIG>, a method of operating the intraoperative nerve monitoring system <NUM> is shown. The method includes a step <NUM> of inserting the ET tube <NUM> within the trachea <NUM> of the patient; a step <NUM> of sensing, with the pressure sensor assembly <NUM>, an amount of pressure between the surface electrode <NUM> and a target tissue <NUM>; a step <NUM> of determining, with the controller <NUM>, whether the amount of pressure exceeds a pressure threshold; a step <NUM> of outputting, with the output device <NUM>, the first indicator <NUM> based on whether the amount of pressure exceeds the pressure threshold to facilitate proper placement of the ET tube in the trachea; a step <NUM> of monitoring, with the surface electrode <NUM>, the nerve activity within the trachea <NUM> while the ET tube <NUM> is inserted within the trachea <NUM>; and a step <NUM> of outputting, with the output device <NUM>, a second indicator <NUM> based on the nerve activity. While the steps <NUM>-<NUM> of the method are shown as proceeding in a particular order in <FIG>, the steps of any method described herein may be ordered in any suitable order.

The step <NUM> of inserting the ET tube <NUM> within the trachea <NUM> is illustrated in <FIG>. As shown, and as previously described, the ET tube <NUM> is at least partially inserted within the trachea <NUM>. The step <NUM> of sensing, with the pressure sensor assembly <NUM>, the amount of pressure between the surface electrode <NUM> and the target tissue <NUM> is shown in <FIG>. As shown, and as previously described, the target tissue <NUM> is the laryngeal muscle <NUM>. The step <NUM> of monitoring, with the surface electrode <NUM>, nerve activity within the trachea <NUM> is shown in <FIG>. As shown and as previously described, the surface electrode <NUM> is configured to monitor the nerve activity of the valgus nerve <NUM> and the laryngeal nerve <NUM>.

<FIG> illustrates the step <NUM> of determining whether the amount of pressure between the surface electrode <NUM> and the target tissue <NUM> exceeds a pressure threshold. In the instance of <FIG>, the processor <NUM> of the controller <NUM> receives the pressure signal <NUM> from the pressure sensor assembly <NUM>, which corresponds to the amount of pressure, and compares the pressure signal <NUM>, using a comparator <NUM>, to a pressure threshold PT value stored in the memory <NUM> of the controller <NUM>. The controller <NUM> then outputs the output signal <NUM> to the output device <NUM>. In other instances, the controller <NUM> may perform step <NUM> using different components. For example, the controller <NUM> may perform step <NUM> without the comparator <NUM>, or may substitute the comparator <NUM> for any other device suitable for comparing the pressure signal <NUM> to the pressure threshold PT, such as a microprocessor. Additionally, the controller <NUM> may perform step <NUM> without the use of the processor <NUM> and/or the memory <NUM>.

In other instances, the controller <NUM> may determine whether the amount of pressure between the surface electrode <NUM> and the target tissue <NUM> falls within a pressure range. For example, in some instances, such as the examples of the first indicator <NUM> shown in <FIG>, the first indicator <NUM> may include a numerical indicator <NUM> configured to output a whole number based on the amount of pressure during step <NUM>. Each of the whole numbers may correspond to a range of pressures. As such, during step <NUM>, the controller <NUM> may determine which pressure range the amount of pressure falls within during step <NUM>. For example, in <FIG>, the numerical indicator <NUM> outputs a number between "<NUM>" to "<NUM>", inclusive, during step <NUM>. The numbers "<NUM>" to "<NUM>" corresponding to seven increasing ranges of pressure. As such, during step <NUM>, the controller <NUM> may be configured to determine which of the seven ranges of pressure the amount of pressure falls within.

<FIG> also illustrates the step <NUM> of outputting the first indicator <NUM> and the step <NUM> of outputting the second indicator <NUM>. As previously discussed, the controller <NUM> outputs the output signal <NUM> based on determining whether the amount of pressure between the surface electrode <NUM> and the target tissue <NUM> exceeds the pressure threshold PT. As shown in <FIG>, the controller <NUM> may also output the output signal <NUM> based on the nerve signal <NUM>, which corresponds to the nerve activity within the trachea <NUM>. For example, in <FIG>, the processor <NUM> filters the nerve signal <NUM> using the digital filter <NUM> before outputting the output signal <NUM>. In this way, the controller <NUM> outputs the output signal <NUM> based on whether the amount of pressure exceeds the pressure threshold PT and based on the nerve activity. In other instances, the processor <NUM> may optionally omit the filtering of the nerve signal <NUM>. Furthermore, the processor <NUM> may include other components for processing the nerve signal <NUM> received from the surface electrode <NUM>. The controller <NUM> may also optionally omit any processing of the nerve signal <NUM>.

After receiving the output signal, the output device <NUM> may output the first indicator <NUM> based on whether the amount of pressure between the surface electrode <NUM> and the target tissue <NUM> exceeds the pressure threshold PT during step <NUM>. For example, in the instance of <FIG> and <FIG>, the controller <NUM> may determine that the amount of pressure does not exceed the pressure threshold PT during step <NUM>. As such, during step <NUM>, the output device <NUM> may output the first indicator <NUM>, which may include the numerical indicator <NUM> and the indication of the adjustment <NUM>. In <FIG>, the numerical indicator <NUM> outputs a "<NUM>" for the first number 51a and the second number 51b, suggesting that the ET tube <NUM> is properly placed. In <FIG>, the indication of the adjustment <NUM> includes the indication of proper placement <NUM> to indicate that the ET tube <NUM> is properly placed.

After receiving the output signal <NUM>, the output device <NUM> may also output the second indicator <NUM> based on the nerve activity during step <NUM>. For example, referring to <FIG>, the output device <NUM> may output the second indicator <NUM> based on the nerve activity sensed by the surface electrode <NUM>. In <FIG>, the output device <NUM> outputs the second indicator <NUM>, which includes the waveform 50a of the nerve activity of the valgus nerve <NUM> and the waveform 50b of the nerve activity of the laryngeal nerve <NUM>.

<FIG> illustrates a second instance of the method, wherein the pressure sensor assembly <NUM> is configured to sense the amount of pressure between the surface electrode <NUM> and the target tissue <NUM> by sensing the amount of pressure between the surface electrode <NUM> and the target tissue <NUM> at each of at least two regions spaced apart from one another on the outer circumferential surface S. For example, referring to <FIG>, the at least two regions may be the four previously described regions Ra, Rb, Rc, and Rd. As such, while the method of <FIG> includes the previously described steps <NUM>, <NUM>, and <NUM>, the method also includes instances of the previously described steps <NUM>, <NUM>, and <NUM>, which are illustrated as steps <NUM>', <NUM>', and <NUM>', and which include steps <NUM>, <NUM>, and <NUM>, respectively, described below.

As shown in <FIG>, the step <NUM>' includes the step <NUM> of sensing, with the pressure sensor assembly <NUM>, the amount of pressure at each of at least two regions. Step <NUM>' is further illustrated in <FIG>. As shown, the pressure sensor assembly <NUM> includes the pressure sensors 18a, 18b, 18c, and 18d, which are configured to sense the amount of pressure between the surface electrode <NUM> and the target tissue <NUM> at the regions Ra, Rb, Rc, and Rd, respectively.

Also shown in <FIG>, the step <NUM>' includes the step <NUM> of determining, with the controller <NUM>, whether the amount of pressure at each of the at least two regions exceeds the pressure threshold PT. For example, referring to <FIG>, the pressure signal <NUM> may include the amount of pressure at each of the regions Ra, Rb, Rc, and Rd of <FIG>. The processor <NUM> may then determine whether the amount of pressure at each of the regions Ra, Rb, Rc, and Rd exceeds the pressure threshold PT before outputting the output signal <NUM>. In such an instance, where the controller <NUM> determines whether the amount of pressure at a plurality of regions exceeds the pressure threshold PT, the pressure threshold PT may be an array stored in the memory <NUM>. As such, the pressure threshold array may output a specific pressure threshold PT value for each of the regions Ra, Rb, Rc, and Rd.

Also shown in <FIG>, the step <NUM>' includes a step <NUM> of outputting the first indicator <NUM> based on whether the amount of pressure at each of the at least two regions exceeds the pressure threshold PT. <FIG> illustrates an instance where the first indicator <NUM> includes the numerical indicator <NUM> based on the amount of pressure between the surface electrode <NUM> and the target tissue <NUM> at the first and second regions 16a, 16b. For example, the first indicator <NUM> indicates that the amount of pressure at the first region 16a exceeds the pressure threshold PT. In an instance where the at least two regions are the regions Ra, Rb, Rc, and Rd of <FIG>, the controller <NUM> may determine that the amount of pressure at the regions Ra and Rb exceeds the pressure threshold PT during step <NUM>. As shown in <FIG>, the output device <NUM> may then output the first indicator <NUM> including the numerical indicator <NUM> during step <NUM> to indicate that the amount of pressure at the first region 16a is too high and exceeds the pressure threshold PT. In this way, the numerical indicator <NUM> of the first indicator <NUM> indicates that the ET tube <NUM> should be urged distally to facilitate proper placement.

<FIG> illustrates an instance where the first indicator <NUM> includes the indication of the adjustment <NUM> based on the amount of pressure between the surface electrode <NUM> and the target tissue at the third and fourth regions 16c, 16d. For example, the controller <NUM> may determine that the amount of pressure at Ra and Rc exceeds the pressure threshold PT during step <NUM>. The output device <NUM> may then output the first indicator <NUM> including the indication of the adjustment <NUM> during step <NUM> to indicate that the ET tube <NUM> should be rotated clockwise A1 to facilitate proper placement.

It will be further appreciated that the terms "include," "includes," and "including" have the same meaning as the terms "comprise," "comprises," and "comprising.

Claim 1:
An endotracheal, ET, tube assembly configured for nerve monitoring and pressure sensing, the ET tube assembly comprising:
an ET tube (<NUM>) comprising an outer circumferential surface and a length sufficient for insertion within a trachea of a patient, the ET tube (<NUM>) being configured to be at least partially inserted within the trachea;
a surface electrode (<NUM>) wrapped about a portion of the outer circumferential surface of the ET tube (<NUM>), the surface electrode (<NUM>) being configured to contact a target tissue and monitor nerve activity when the ET tube (<NUM>) is at least partially inserted within the trachea; and
characterised in that it further comprises:
a pressure sensor assembly (<NUM>) coupled to the outer circumferential surface of the ET tube (<NUM>), the pressure sensor assembly (<NUM>) being configured to sense an amount of pressure between the surface electrode (<NUM>) and the target tissue.