Systems and methods for targeted stimulation in a tracheal phrenic nerve stimulation device

Abstract

A system and method for targeted stimulation with a tracheal phrenic nerve stimulation device that can include: performing an initialization routine of a stimulation module that determines a set of stimulation parameters, the initialization routine comprises: cycling through electrode groupings, detecting a response in a respiratory signal for each electrode grouping, and determining a select electrode grouping as part of the stimulation parameters; and operating a stimulation module using the set of stimulation parameters.

Description

SYSTEMS AND METHODS FOR TARGETED STIMULATION IN A TRACHEALPHRENIC NERVE STIMULATION DEVICECROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This Application claims the benefit of U.S. Provisional Application No. 63 / 666,039, filed on 28-JUN-2024, titled “SYSTEMS AND METHODS FOR TARGETED STIMULATION IN A TRACHEAL PHRENIC NERVE STIMULATION DEVICE”, which is incorporated in its entirety by this reference.TECHNICAL FIELD

[0002] This invention relates generally to the field of phrenic nerve stimulation and more specifically to a new and useful system and method for targeted stimulation in a tracheal phrenic nerve stimulation device.BACKGROUND OF THE INVENTION

[0003] Mechanical Ventilation (MV) is a lifesaving treatment for patients with acute respiratory failure. However, it can lead to a rapid decrease in diaphragm muscle endurance and strength, a condition known as ventilator-induced diaphragmatic dysfunction (VIDD). MV can also contribute to ventilator induced lung injury (VILI). Nearly 1 million Americans received MV each year prior to the COVID-19 pandemic— the number has since risen significantly. While lung-protective modes of ventilation are becoming more utilized, the importance of diaphragm-protective strategies and its benefits for diaphragm health and improved lung function is just starting to be understood. VILI and VIDD have a significant societal burden due to poorer healthcare outcomes. Patients that undergo MV have an in-hospital mortality rate of 34.5%, and only 30.8% are discharged from hospitals. In addition, their consequences also bring significant economic burden in increased healthcare costs. Both VILI and VIDD prolong a patient’s length of stay in the ICU, increasing hospitalization costs. Current approaches to preventing ventilator associated conditions are limited to simple physicaltherapy protocols consisting of decreasing or removing MV support for brief periods of time and using ventilator strategies that minimize external support and use of paralytic medications. Diaphragm stimulation via the phrenic nerve, responsible for motor control of the diaphragm, can help prevent VIDD and VILI in MV patients.

[0004] Thus, there is a need in the phrenic nerve stimulation field to create a new and useful system and method for targeted stimulation in a tracheal phrenic nerve stimulation device. This invention provides such a new and useful system and method.BRIEF DESCRIPTION OF DRAWINGS

[0005] FIG. 1 is a schematic representation of a system variation.

[0006] FIG. 2 is a detailed schematic representation of a stimulation module with flexible splines.

[0007] FIGs. 3A-3C are detailed schematic representations of a stimulation module viewed in the transverse plane (horizontal plane) with different configurations for targeting the phrenic nerve.

[0008] FIGs. 4A-4C are detailed schematic representations of a side view of a stimulation module deforming during deployment.

[0009] FIG. 5 is a flowchart representation of a method.

[0010] FIG. 6 is a flowchart representation of a method variation.

[0011] FIG. 7 is a flowchart representation of a method variation with details on the initialization routine.

[0012] FIG. 8 is a flowchart representation of a method variation for automatically recalibrating the stimulation parameters.

[0013] FIG. 9 is an exemplary system architecture that may be used in implementing the system and / or method.DETAILED DESCRIPTION OF THE EMBODIMENTS

[0014] The following description of the embodiments of the invention is not intended to limit the invention to these embodiments but rather to enable a person skilled in the art to make and use this invention.1. Overview

[0015] Systems and methods for targeted stimulation in a tracheal phrenic nerve stimulation device may enable a catheter deployed within the trachea of a patient to dynamically adjust stimulation of a set of electrodes to target phrenic nerves in proximity to the trachea. In particular, the systems and methods may be used as part of an electrical stimulation device deployed within an endotracheal tube (ETT) or similar (e.g., tracheostomy tube, laryngeal mask, bronchoscopy port) which is also used to deliver air to lungs of a patient under mechanical ventilation. With this placement, the systems and methods may be non-lacerating and may not require an additional procedure. The system may further deliver diaphragm stimulation as a sole means of respirating a person (e.g., without the patient being on a ventilator). The system may further deliver diaphragm stimulation synchronized with the rhythm of mechanical ventilation, working in coordination with a mechanical ventilator to coordinate a state of ventilation.

[0016] The system and method may be used for more accurately and / or safely stimulating the phrenic nerve, which is responsible for contracting the diaphragm, the primary respiratory muscle. This maybe used to prevent or ameliorate VIDD, prevent or ameliorate VILI, reduce MV weaning times and hospital intensive care unit (ICU) stays, and / or otherwise improving patient outcomes.

[0017] While the systems and methods are primarily described in the context of ETT applications and ventilator support, the approach is not limited to such use cases. One skilled in the art could appreciate the systems and methods could similarly be used or deployed using any suitable airway access device (e.g., tracheal access systems), including but not limited to ETTs, tracheostomy tubes, laryngeal masks, or bronchoscopy ports.

[0018] Similarly, the systems and methods described herein maybe adapted for use in a variety of procedures or clinical contexts involving stimulation of thoracic or nearby peripheral nerves, including but not limited to the phrenic nerve, vagus nerve, or other anatomically adjacent nerve structures. Accordingly, the systems and methods maybeused for targeted peripheral nerve stimulation in the thoracic cavity or upper mediastinal region.

[0019] For example, in thoracic surgeries or procedures where there is a risk of iatrogenic nerve injury, such as phrenic nerve transection, targeted stimulation of the system and method may be used intraoperatively to assess diaphragm innervation, meaning it can help confirm that the phrenic nerve remains functionally intact and capable of controlling the diaphragm.

[0020] Other potential applications may include using phrenic nerve stimulation as an alternative or supplement to mechanical ventilation — for example, to support breathing in patients with respiratory insufficiency when ventilators are unavailable, during ventilator weaning, or as a less invasive option to avoid ventilator-associated complications. The systems and methods may also be used for therapeutic nerve stimulation to modulate vagal tone in cardiac or gastrointestinal conditions, or for diagnostic mapping of nerve function in neuromuscular disorders.

[0021] The described systems and methods maybe incorporated into various airway access tools, surgical instruments, or standalone catheters for these purposes.

[0022] The systems and methods may be used with a specialized stimulation system with a plurality of selectable electrodes. The systems and methods may dynamically select electrodes for use during stimulation (e.g., pacing of stimulation). The electrodes of the stimulation system may be used to stimulate a peripheral nerve.

[0023] As one aspect, the selectable electrodes may be used to dynamically direct stimulation in a direction for stimulating an adjacent nerve. This may help in optimizing or enhancing electrode stimulation positioning. In practice this may mean a stimulation device may be roughly positioned, and the device automatically can adjust how it applies stimulation to target the nearby nerve.

[0024] In addition to optimizing / enhancing electrode utilization, the system and method may also identify a stage of a respiratory cycle via a sensing system such as a respiratory sensor and automatically adjust the stimulation parameters using algorithms to account for patients’ anatomy, rate, and volume of breath. Stimulation parameters such as intensity, frequency, pulse width, and other properties may be set to optimize or enhance results. Continuous or periodic monitoring may be used tomodulate stimulation parameters. The stimulation parameters may be adjusted to patients individually. These dynamic adjustments may decrease airway pressure, allow for pressure differential capabilities, enable feedback loop control, and allow for controlled stimulation in sync with a ventilator machine. In this way, the system and method may deliver patient -specific stimulation that induces controlled, synchronized, smooth contraction of the diaphragm from within the trachea, that mimics a natural breathing state.

[0025] Furthermore, the systems and methods can self-monitor effectiveness of stimulation so that adjustments maybe automatically applied to account for changes. For example, movement of the subject or the stimulation system may alter the impact of the stimulation. The systems and methods can monitor impact so that the device can recalibrate stimulation parameters periodically or as needed.

[0026] The system and method may provide a number of potential benefits. The system and method are not limited to always providing such benefits and are presented only as exemplary representations for how the system and method maybe put to use. The list of benefits is not intended to be exhaustive, and other benefits may additionally or alternatively exist.

[0027] As one potential benefit, the systems and methods may enable direct phrenic nerve stimulation (PNS) that is anatomy independent or at least adaptable to a wide variety of anatomical conditions. The electrode system and dynamic control and operation of such an electrode system by the systems and methods may more accurately limit or focus stimulation to the targeted phrenic nerve(s). In particular, the systems and methods may be able to target stimulation of the right and left phrenic nerve, while avoiding or reducing unintended stimulation of other peripheral parts of the body near the trachea.

[0028] As a related benefit, the systems and methods may provide dynamic patientspecific stimulation, while being a blindly positioned electrode system. In other words, the systems and methods may not depend on additional imaging or complicated positioning systems, and the stimulation device may be more easily positioned within a body.

[0029] As another potential benefit, the systems and methods may provide a less invasive way of addressing ventilator associated complications (VIDD, VILI). By working as a system that can use an existing ETT, the systems and methods may avoid an additional procedure which would typically increase patient morbidity risk.

[0030] As another benefit, the systems and methods may result in improved patient outcomes. By being minimally invasive (e.g., using an existing ETT) and being adaptable to patient-specific anatomies, the systems and methods may provide PNS that is safe and yields better patient outcomes like shorter ventilator wean times, decreasing patient dependence on MV and preventing VIDD and VILI, and / or reducing the financial burden associated with long-term MV and its complications.2. System

[0031] As shown in FIG. 1, a system for targeted stimulation in a tracheal phrenic nerve stimulation device may include a stimulation module 100 comprising a plurality of selectable electrodes 110 with varying placement and a stimulation control system 130. In some variations, the system may additionally include a respiratory sensor system 120.

[0032] The system may use a variety of form factors of the stimulation module 100. In one variation, as shown in FIG. 2, the system includes a stimulation module with a set of flexible splines 102; a set of electrodes 110, wherein a subset of electrodes is positioned on each of the flexible splines 102; and a stimulation control system 130. The stimulation control system 130 may be configured to selectably control a stimulation state of electrode subgroups in the set of electrodes. This dynamic selection and configuration of stimulation maybe used to apply stimulation through only a subset of the electrodes which are determined to provide enhanced stimulation of a targeted nerve. The stimulation control system 130 may assign electrode polarity and activation state on a per-electrode basis, enabling spatially focused stimulation patterns.

[0033] The system is preferably used as part of a system that leverages or integrates with an ETT or another type of airway access device to achieve access to the trachea region of a subject (i.e., patient). Accordingly, in some variations, the system may additionally include an airway access device 140. The system can leverage the placementof the ETT, which delivers air to lungs of patients under mechanical ventilation, as a channel to access the tracheal wall and deliver current to the phrenic nerve. Placement of the stimulation system may therefore be non-invasive (or less invasive) and may not require additional procedures. The device can work in pace with the ventilator to provide diaphragm stimulation that is tailored to each patient and synchronized with the rhythm of inspiration provided by the mechanical ventilator. The device may also work independent of the ventilator to provide diaphragm stimulation that is tailored to each patient.

[0034] The system can include configuration within the stimulation control system 130 to dynamically adjust stimulation parameters needed to achieve appropriate stimulation from within the trachea (e.g., setting pacing of stimulation). An algorithmic process maybe used to select an enhanced set of parameters tailored to each patient. The activation of muscles via electrical stimulation depends on several variables (frequency, current, duration, interval, etc.) as well as specific positioning relationships between the electrodes and a patient’s anatomy. Each nerve and nerve type may be activated and respond differently to combinations of these stimulation variables. Additionally, muscle responses when the nerve is activated also vary, and the tissue that conducts the electric stimulus also influences these effects. The system can include configuration to dynamically adjust and adapt so as to identify parameters to induce the desired breathing state.

[0035] As another technical challenge addressed by the system, the system may be configured to deliver effective stimulation to the phrenic nerve while avoiding or minimizing undesired stimulation of other conductive systems (e.g., vagus and brachial plexus nerves, heart) as well as avoiding other undesired physiological effects. The stimulation control system 130 may adjust stimulation applied to the plurality of electrodes 110 to target desired regions of stimulation and to avoid or reduce stimulation in undesired regions. In some variations, the system may perform one of directional targeting or electrical stimulation property enhancement. In some variations, the control system may enable directional targeting and enhancing electrical stimulation pacing properties.

[0036] The stimulation module 100 functions to apply stimulation. The stimulation module may be designed for delivering stimulation from within the tracheal region.

[0037] The stimulation module 100 will include a set of electrodes 110 which can be a plurality of electrodes distributed at different points on the stimulation module 100. Some variations for configuration and design of the set of electrodes 110 are described herein.

[0038] The stimulation module 100 can be collapsable and / or expandable. The stimulation module 100 maybe initialized in a collapsed state and configured to expand radially during deployment. When expanding radially during deployment, the stimulation module 100 maybe described as being in a deployed state.

[0039] The collapsed state can refer to the structure or body of the stimulation module too being in a physical configuration that fits within a defined in a region in transverse plane (plane defined perpendicular to longitudinal axis) that is less than when in a deployed state. In particular, the collapsed state of the stimulation module 100 may have an area in the transverse plane less than that of an inner surface of an airway access device 140. For example, the stimulation module 100 can fit within an ETT when in a collapsed state.

[0040] The deployed state of the stimulation module too may describe the body of the stimulation module 100 at least partially expanding outward in the transverse plane away from a longitudinal axis. The deployed state may be triggered or deployed when the stimulation module 100 exits an airway access device 140 such as an ETT. In the deployed configuration, the stimulation module 100 expands to promote stable conductive contact between the electrodes and the tracheal wall, conforming to the surrounding tissue to ensure effective signal delivery.

[0041] Different physical designs may be used for physically having collapsed and deployed states. In one particular variation, the stimulation module 100 can include flexible splines 102, which function as deployable structural members configured to promote conductive contact with surface of a tracheal tube of a subject.

[0042] The stimulation module 100 may alternatively use alternative designs that similarly support having an array of electrodes.

[0043] The stimulation module 100 can be attached to or part of a distal end of a catheter or an airway access device such as an airway tube like an ETT. In some variations, the flexible splines 102 may support a circumferential configuration of the set of electrodes 110, wherein different subsets of electrodes maybe arranged at different radial positions about a defined longitudinal axis of the stimulation module 100. Herein, the longitudinal axis maybe defined along the length of the stimulation module 100 and maybe substantially aligned with or in a substantially similar direction of the catheter, airway access device.

[0044] A set of selectable electrodes no functions to provide a number of possible stimulation sites within the system. The set of electrodes 110 can be a plurality of selectable electrodes that are integrated into a stimulation module 100 or other suitable device at the distal end of a stimulation catheter. The plurality of selectable electrodes no maybe integrated into a structural support system of the stimulation module 100, where the structural support system physically positions electrodes in different regions within some targeted region such as the tracheal region. The set of electrodes 110 will be distributed across at least two different possible locations or regions. More specifically the set of electrodes 110 may be an array of electrodes across a number of different positions, whereby stimulation may be directed in a number of different directions through selection of a subset of the electrodes.

[0045] The electrodes may also be conductively connected to the stimulation control system 130 for dynamic control of stimulation. In one variation, conductive lines maybe run through a connected catheter to the stimulation control system 130. In another variation, electrode control circuitry may be integrated within or near the stimulation module too which may manage activation and control of stimulation. In this variation, communication data lines may run through or along a catheter to the stimulation control system 130. In another variation, the stimulation control system 130 may communicate wirelessly to the set of electrodes 110.

[0046] In some implementations, the control system may provide individual control of electrodes, while in others, electrodes may be grouped into subarrays for concurrent control. In one variation, the set of electrodes 110 maybe connected or integrated with the stimulation control system 130 so that the set of electrodes may be selectablyactivated or deactivated as different electrode subgroups. In one variation, each electrode maybe individually controlled by the stimulation control system 130. In another variation, a subset of the set of electrodes 110 may be individually controlled by the stimulation control system 130. Another subset of the set of electrodes no maybe controlled as groups. For example two electrodes maybe controlled together where stimulation state is connected. In yet another variation, each subgroup controlled by the stimulation control system 130 may include a plurality of individual electrodes.

[0047] The control over the electrodes may activate or deactivate the electrodes. An electrode in an activated state may deliver a current pulse defined by stimulation parameters such as amplitude, pulse width, and waveform shape. In some variations, current-controlled stimulation is used to ensure consistent charge delivery across varying tissue impedance. An electrode in a deactivated state does not participate in current delivery and may be electrically disconnected, isolated, or otherwise maintained at a non-stimulating potential by the stimulation control system 130. An electrode in a deactivated state maybe subsequently activated based on updated stimulation parameters. Similarly, an electrode in an active state may be changed to a deactivated state.

[0048] In addition to the active and inactive states of electrodes, the polarity and / or stimulation parameters of each electrode or subgroup of electrodes maybe dynamically assigned by the control system, enabling variable stimulation field configurations. In some variations, one or more electrodes maybe selectably used as an anode or a cathode. In some variations, one or more electrodes may have particular parameters fixed or linked to parameters of other electrodes.

[0049] Related to the control of electrode polarity, the set of selectable electrodes 110 may include different pairs of positive and negative electrodes. In one variation, the plurality of selectable electrodes 110 includes defined pairs of positive and negative electrodes. In another variation, the plurality of electrodes 110 may have positive and negative electrodes that can be individually selectable. In this way, one negative electrode maybe paired with different positive electrodes. In one variation, there may be an asymmetrical number of positive and negative electrodes, wherein there are differing number of positive and negative electrodes. In another variation, the polarityof electrodes maybe adjustable such that one or more electrodes may have polarity controlled and changed by the control system 130.

[0050] In one variation, the plurality of selectable electrodes no is configured or arranged as a circumferential array of electrodes, wherein subsets of the set of electrodes 110 may be selectable for stimulation in different radial orientations / directions. The plurality of selectable electrodes may include at least a subset of electrodes that have substantially consistent longitudinal position along the length of the catheter (e.g., along tracheal tube), but at different angular positions around a defined circumference (the circumference being defined perpendicular to the longitudinal axis). The circumferential array of electrodes maybe used to enable generation of electric field(s) directed in select circumferential regions. In other words, the circumferential array may enable selection of electrode pairs or groupings thereby directing stimulation in different anatomical regions to achieve directional targeting. In practice the stimulation module 100 may be positioned at an end of an ETT. The angular position of the stimulation module 100 relative to targeted nerve may not be known from just this initial positioning of the stimulation module 100. However, through calibrating the stimulation module 100, a subset of electrodes maybe selected which enhance stimulation of the targeted nerve. This may in some variations be selection of electrodes in nearer proximity to the targeted nerve than those not selected. However, depending on anatomy the selection may also be based on which pairing or grouping of electrodes achieves a targeted level of stimulation response, which maybe dependent on internal anatomy of a subject.

[0051] As another variation, the plurality of selectable electrodes 110 may also include an array of electrodes with longitudinal variation of electrode positioning. In other words, electrodes may be selectable with differing longitudinal positioning along an axis substantially defined along the length of a stimulation catheter. For example, two or more electrodes may have substantially similar longitudinal positioning but with differing radial positioning. In one variation, the set of electrodes includes groups of at least four electrodes aligned along shared longitudinal paths. In one such variation, at least four electrodes may each be positioned at distinct longitudinal positions on individual splines 102 of the stimulation module 100. Having multiple electrodes indifferent longitudinal positions may provide flexibility in how the stimulation module 100 is exactly positioned. As shown in FIG. 4A-4C, four electrodes maybe used, for example, to achieve high reliability for at least two electrodes to have suitable conductive contact with tissue to account for variance on exact orientation of the stimulation module 100.

[0052] When a group of electrodes is selected for stimulation, the select electrodes maybe selected along one radial orientation of the stimulation module 100. For example, the electrodes in an activate state may all be selected along one spline. However, in some variations, dynamic activation of select electrodes maybe performed from different radial orientations. For example, one electrode maybe activated from one spline and another electrode activated in an opposite polarity from an adjacent or otherwise different spline.

[0053] As mentioned, the stimulation module 100 may include a set of splines, which function as structural supports enforcing circumferential positioning. A set of splines can be distinct lengths that are radially positioned. Each spline may include one or more electrodes as shown in FIG 2. In one exemplary variation, the plurality of selectable electrodes 110 may include at least six electrode pairs with a pair of electrodes integrated on an individual spline. In another variation, one or more splines may include at least four electrodes.

[0054] The flexible splines 102 maybe connected at a proximal end of a catheter. In one variation, each flexible spline maybe configured or otherwise shaped to arc outward such that a circumferential spread increases along the longitudinal direction (in the distal direction). The flexible splines 102 may connect at a common junction at a distal end of the stimulation module 100. Alternatively, the flexible splines 102 may form an arc that extends to a distal end of the stimulation module 100 at or near a midpoint of the spline but is not terminated and instead bends back to connect again at the proximal end of the stimulation module 100. As mentioned, each spline may include two or more electrodes. In this version, electrodes on each half of the spline may be associated with opposite radial positions.

[0055] The flexible splines may include two or more electrodes positioned at different lengths along the spline. Three or more electrodes may be used to provide longitudinaloptionality for selection of an electrode. For example, four electrodes may provide optionality for a selection of distal and proximal activated electrodes. However, there may be versions where there is a single electrode such as when there is a common electrode not on the spline to form an electrode pair with a select electrode on a spline.

[0056] In some variations, the stimulation module 100 may additionally or alternatively include one or more distal and / or proximal electrode that is not positioned on a flexible spline. This may be used as a common cathode or anode. In another variation, a set of electrodes may include a subset of electrodes that form a common anode or cathode. As a common anode or cathode, these electrodes maybe conductively linked and configured as either an anode or cathode, where the other electrodes may be selectively activated to serve as an electrode of an opposite polarity.

[0057] The flexible splines 102 may enable the stimulation module 100 to deform from a collapsed state when passing the stimulation module 100 through an ETT or other type of passageway and then expand to an expanded state after exiting a distal end of the ETT or passageway. The flexible splines 102 and the stimulation module 100 may be designed such that it naturally deforms between such states. For example, the splines 102 maybe biased to expand radially from a compressed configuration to contact a tracheal wall upon deployment, supporting electrode placement circumferentially around a tracheal lumen. As shown in FIG. 4A, the splines may have an expanded stable state. The splines may compress to fit through an airway access device 140 like an ETT as shown in Fig. 4B. Then, when the stimulation module exits the distal end of the ETT or other type of passageway, the stimulation module 100 may expand within the body (within the trachea) as shown in FIG. 4C. This may also include deforming in both directions. In this way, the device can be easily inserted and removed.

[0058] Alternatively, the system may include some mechanical or other form of actuation to trigger transitioning between collapsed and expanded states.

[0059] The splines may be a thin strip with geometry to that promotes flexibility in desired directions. In general, the splines can be flexible for deformation inward and outward radially. The splines may be made of a variety of flexible materials. In one variation, they may be made of a memory shape metal like nitinol (an alloy of nickel and titanium). Such a memory shape metal may be used to establish a balloon shape whendeployed. In one variation, the flexible splines may be formed from flexible printed circuit board substrate. The flexible printed circuit board (PCB) splines may have exposed electrode pads to form the electrodes. Conductive traces maybe shielded by outer surfaces of the circuit board. In another variation, the electrodes may be formed from a platinum iridium alloy. Other conductive materials (e.g., a biocompatible conductive) may also be used in forming the electrodes, which may function to provide electrochemical stability during long-term stimulation in airway environments. A coating or other type of insulating layer may be formed on the biocompatible materials to define an exposed surface of the electrode. In one variation, the spline may be made of a nitinol underwire, a plastic extrusion fed over the underwire and a flexible PCB glued or otherwise adhered on top of the extrusion.

[0060] Other structural support systems may alternatively be used. In another exemplary variation, the structural support could be a rigid or flexible longitudinal structure (e.g., cylindrical structure) with electrodes integrated around an outer surface of the structure.

[0061] The system may include an interface to a respiratory signal. More generally, the system includes a respiratory sensor system 120, which functions as a mechanism for the system to measure, sense, or otherwise monitor respiratory state of the patient and / or a respirator device.

[0062] In one variation, the system includes an interface with a mechanical ventilator and is configured to receive a ventilator signal indicating an inspiratory or an expiratory phase. In one such implementation, the respiratory sensor system 120 may include a pressure sensor and / or a flow sensor integrated with the ETT (e.g., to track the stage of a respiratory cycle) or within the ventilatory circuit of the mechanical ventilator. The sensor may be used so that the system may induce stimulation of a phrenic nerve in synchronization with a ventilator (e.g., during the inspiratory cycle) or to induce a cadence of respiration without a ventilator.

[0063] As an additional or alternative variation, a data signal from a ventilator device may be accessed. A data interface with a respiratory device like a ventilator may allow respiratory state to be monitored indirectly based on how the respiratory device is operating.

[0064] The ventilator data signal may communicate timing signals, pressure or flow waveforms, a digital trigger signal, and / or any suitable information that maybe used to understand operation of the ventilator.

[0065] In addition to or as an alternative to sensing the respiration of a patient, the respiratory sensor system 120 may include one or more sensor system for tracking respiration of a subject. For example, the respiratory signal system may include at least one sensor selected from the group consisting of a pressure sensor, a flow sensor, an accelerometer, an external camera monitoring a patient, a heart rate monitoring device (e.g., an ECG), a muscle electromyography (EMG) sensor, an accelerometer, and / or other sensing systems. Sensor integration may occur at the tube interface, on the catheter shaft, or externally, enabling multimodal feedback for stimulation control.

[0066] In some variations, the sensor system may additionally be used to monitor activation of the diaphragm itself. For instance, a muscle electromyography (EMG) sensor may be configured to detect myoelectric signals corresponding to diaphragmatic contraction, providing direct confirmation of nerve activation. Similarly, an accelerometer may be positioned to detect mechanical movement of the chest or abdominal wall, serving as an indirect indicator of diaphragmatic motion. These signals may be used in combination with or as a proxy for respiratory metrics to assess stimulation efficacy, adapt stimulation parameters, or trigger recalibration routines when diaphragm response deviates from expected patterns.

[0067] The stimulation control system 130 functions to control and manage stimulation and / or setting of pacing for a stimulation module 100. The stimulation control system 130 or more concisely described as the control system 130 can be conductively connected to the stimulation module 100 or a connected electronic device that facilitates controlling stimulation delivered by the stimulation module 100. As mentioned, in some variations, the stimulation control system 130 may be communicatively connected through a wireless data connection.

[0068] The stimulation control system 130 can be configured to selectably activate or deactivate electrode subgroups of the set of electrodes. Furthermore, the stimulation control system 130 may include at least two modes: a calibration mode which can beused when initiating the stimulation module 100 and a stimulation mode which is when stimulation is actively used for helping the subject.

[0069] The control system 130 can additionally be connected to the respiratory sensor system 120 so that stimulation may be set and adjusted based on current conditions of a patient.

[0070] In one variation, the system may additionally include a user interface control panel connected to or otherwise integrated with the control system 130. The user interface may be a digital interface or a physical interface. The user interface may include use input elements which maybe used for changing modes of stimulation module 100 and / or for selecting, testing, or using different stimulation parameters. The user interface may additionally include output devices to communicate or indicate state of the stimulation module 100 and / or the subject. For example, a display maybe used to display feedback on stimulation and monitored respiratory information.

[0071] In some variations, the control system 130 may automatically cycle through and automatically select a best set of stimulation parameters, which may help in automatically steering stimulation towards targeted nerves and conditioning the stimulation for enhanced effects. However, in some alternative variations or modes of use of the system, a user may manually control. In one example, a user may manually cycle through different stimulation parameters to manually set the stimulation direction / orientation and / or stimulation parameters. In some examples, the system may automatically set some stimulation parameters, and a user may set or edit some subset of stimulation parameters.

[0072] The control system 130 can adjust stimulation according to the position of the stimulation module 100 relative to a patient’s anatomy. In particular, the control system 130 may determine and then set stimulation configuration to target one or more adjacent nerves. For example the control system 130 may set stimulation to target one or both phrenic nerves, which in many cases will be on substantially opposing sides of stimulation module 100. The control system 130 may determine a subset of electrodes to use from the plurality of electrodes 110 and / or how to adjust stimulation parameters for stimulation pacing customization across the selected electrodes.

[0073] To facilitate this targeting and customization of stimulation, the control system 130 may include an initialization mode that functions to calibrate or set configuration of stimulation. During an initialization mode, different pairs or groupings of electrode configurations may be used for different test stimulation signals. The stimulation tests may be different configurations of electrodes in various states of active and inactive states and / or with differing stimulation properties.

[0074] The control system 130 may monitor changes in the data from the sensor system 120 for different effects. This maybe used to understand the positioning of the stimulation module 100 relative to the anatomy and thereby determine which pair(s) of electrodes should be used for phrenic nerve stimulation.

[0075] While the system is primarily used for stimulating, in some alternative applications, the electrodes may alternatively or additionally be used for sensing or monitoring. Stimulation or sensing testing may still be performed to calibrate and determine which electrodes are oriented in proximity to targeted nerves. Sensing through electrodes may be used in alternative applications (When not used primarily for stimulation, the stimulation module 100 may more generally be referred to as an electrode module).

[0076] As shown in FIG. 3A-3C, the arrangement of the stimulation module too can have different relative positioning to a targeted nerve depending on the patient anatomy and how the stimulation module 100 was placed in the body. The plurality of electrodes will generally have some electrodes better positioned for delivering stimulation. In one example shown in FIG. 3A, pair 2 and pair 5 electrodes maybe closest to the phrenic nerves in one instance. Accordingly, the electrode pair P2 and N2 may generate an electrical field to stimulate the phrenic nerve on one side. Not shown, but the electrode pair 5 may be selected to target the other nerve.

[0077] If the stimulation module, were shifted relative to the nerve for pair 3 and 6 electrodes to be in closer proximity then cycling through the stimulation parameters may end up selecting pair 3 and / or pair 6 depending on what nerve is targeted. Fig. 3B shows pair 3 being used. In another example shown in FIG. 3C, pair 3 and pair 6 electrodes maybe closest and the selection of electrode groups may use a combination of electrode pairs for stimulating the phrenic nerve on one side. For example, pair 2 andpair 3 may be used in combination for stimulation on one side and pair 6 and pair 5 may be used in combination for stimulation on the other side as shown in FIG. 3C.

[0078] The control system 130 may additionally determine other stimulation parameters to use. In this way, the system can adjust stimulation pacing parameters like polarity, frequency, current, duration, interval, and / or other suitable stimulation parameters. In one variation, frequency may be determined between a range 1-100 Hz; current (e.g., amplitude of the peak voltage of a pulse) between a range of 2-1000 mA; duration (e.g., duration of the peak voltage) between a range of 100-1000 microseconds; period (e.g., duration of a pulse) between 200-5000 ms.; and waveform (e.g., manner that the voltage is delivered over time) selected options like ramped, triangular, trapezoidal, square, monophasic, biphasic, and asymmetric waveforms. Stimulation parameters applied to each electrode pair of the stimulation module 100 maybe variable and independently controlled. Determination of the stimulation parameters can similarly be performed during an initialization mode and / or during real-time monitoring of the patient during stimulation and ventilation.

[0079] The system may additionally include an airway access device 140 which functions as conduit for the stimulation module 100 to access the tracheal region.

[0080] In one variation, the airway access device 140 may be an ETT. The stimulation module 100 maybe inserted into position by passing through the ETT. A catheter may be used to facilitate physical manipulation of the stimulation module 100 and to form conductive contact with electronics of the stimulation module 100.

[0081] The ETT can be the same ETT also used by a connected ventilator. The system may include an ETT connector that allows a catheter to be inserted into the ETT while the ETT maintains a connection to a ventilator system. In some variations, there may be no ventilator connected such as if the system is used independently to stimulate respiration.

[0082] In applications outside of ETT use, the airway access device 140 may alternatively be a tracheostomy tube, a laryngeal mask airway (LMA), a bronchoscopy port, or another tracheal access device, or hollow catheter like device. In such variations, the stimulation module 100 may be introduced through the lumen of the access device and positioned adjacent to the tracheal wall to enable effective stimulation. Thesealternative airway access devices may similarly support integration of the stimulation module 100 while maintaining a conduit for airflow. The design and deployment approach may be adapted based on the anatomical access route and procedural context.

[0083] For example, a tracheostomy tube may allow more direct insertion from the front of the neck into the trachea. In contrast, an LMA is typically positioned above the vocal cords, sealing around the top of the windpipe (e.g., in a supraglottic region) without entering it. ETTs and tracheostomy tubes, in some cases, may reach below the vocal cords and enter the trachea directly (e.g., in the subglottic region). The system may be configured to accommodate these anatomical differences to ensure consistent electrode positioning and reliable stimulation delivery across different airway access devices.3. Method

[0084] A method for targeted stimulation in a tracheal phrenic nerve stimulation device functions to control a stimulation module to dynamically set and manage stimulation of the device. The method may enable dynamic steering or directing of stimulation to isolate or focus stimulation in a desired region. The method can additionally or alternatively adjust stimulation parameters for current conditions of a patient.

[0085] As shown in FIG. 5, a method targeted stimulation in a tracheal phrenic nerve stimulation device may include performing an initialization routine that determines a set of stimulation parameters S110 and operating a stimulation module using the set of stimulation parameters S120. The method may additionally be performed in connection with deploying a stimulation module within an ET tube S100 as shown in FIG. 6.

[0086] The method in particular may use the initialization routine to calibrate how stimulation should be applied across a plurality of electrodes. As shown in FIG. 5 the initialization routine maybe used for determining electrode grouping Sin and / or determining pacing parameters S112. Electrode grouping may function to steer or direct stimulation in one or more targeted region. This preferably selects which subset of electrodes to use of a plurality of electrodes based on which are in better orientations tostimulate the targeted nerves. Determining pacing parameters may be used to set electrical properties for stimulation.

[0087] In one variation, determining electrode grouping S111 and more broadly performing an initialization routine that determines a set of stimulation parameters S110 can include: cycling through electrode groupings S113, detecting a response in a respiratory signal for each electrode grouping S114, and determining a select electrode grouping as part of the stimulation parameters S115.

[0088] Additionally or alternatively, determining pacing parameters S112 and more broadly performing an initialization routine that determines a set of stimulation parameters S110 can include: cycling through pacing parameters S116 and selecting stimulation parameters in the set of stimulation parameters S117.

[0089] As shown in FIG. 7, a method for operating a tracheal nerve stimulation device may include performing an initialization routine of a stimulation module that determines a set of stimulation parameters S110, the initialization routine including: cycling through electrode groupings S113, detecting a response in a respiratory signal for each electrode grouping S114, and determining a select electrode grouping as part of the stimulation parameters S115; and operating a stimulation module using the set of stimulation parameters S120. The initialization routine may test different combinations of positive and negative electrodes to identify groupings of electrodes in a set of electrodes that produce diaphragm movement, as measured via respiratory pressure, flow sensors, or other patient physiological signals. In such a variation, the initialization routine may add additionally or alternatively include cycling through pacing parameters S116 and selecting stimulation parameters in the set of stimulation parameters S117. This may determine the electrical pacing parameters. These maybe performed as distinct steps, or the method may cycle through testing combinations of electrode groupings and stimulation pacing parameters.

[0090] The method is preferably performed in connection with the system described herein. As such, the method may include providing a stimulation module S100 as shown in FIG. 6. The method may alternatively be performed with any suitable system.

[0091] Providing the stimulation system may specifically include providing the stimulation module in connection with a control system, wherein the stimulationmodule includes a set of selectable electrodes. Preferably, the stimulation modules have a plurality of electrodes that may be controlled such that a subset of electrodes may be used for stimulation so as to control where stimulation is focused / directed. In some particular variations, the set of electrodes of a stimulation module can be configured as a circumferential array, wherein subsets of the set of electrodes are selectable for stimulation in different radial orientations. In other words, the circumferential array may enable selection of electrode pairs or groupings thereby directing stimulation in different anatomical regions to achieve directional targeting. Any of the variations of the system described herein may be used.

[0092] In connection with providing the stimulation module, the method may additionally or alternatively include deploying the stimulation module, which functions to physically position a stimulation module within the trachea of a patient.

[0093] In ETT applications, the stimulation module is deployed within an ET tube, but as described other applications may have the stimulation module through other airway access devices. In ETT related applications this may include initially deploying the stimulation module at a distal end of an endotracheal tube. Performing the initialization routine may then be performed subsequent to deployment of the stimulation module.

[0094] The deployment of the stimulation module may be made blindly, which is to say without using imaging or sensing to determine final positioning of the stimulation module. In one such variation, deploying the stimulation module may include moving a stimulation module that is connected to the end of a catheter to a distal end of an ET tube. When exiting the ET tube, the stimulation module can automatically deploy or be triggered into deploying.

[0095] Block S110, which includes performing an initialization routine of a stimulation module that determines a set of stimulation parameters, functions to test and configure the stimulation system for customized stimulation. The initialization routine maybe a mode of operation (e.g., initialization or calibration mode) or a series of operations. It maybe triggered when initializing the stimulation system. The initialization routine may be used for calibrating or setting configuration of a stimulation system as such the initialization routine may alternatively be referred to as acalibration routine or mode. Performing the initialization routine may include performing a set of different calibration operations. One set of calibration operations maybe used to determine a subset of electrodes to use for stimulation, wherein the stimulation module includes a plurality of selectable electrodes. This may be used to steer stimulation towards the targeted phrenic nerve(s). For example, where the stimulation module includes a set of electrode pairs each along one circumferentially arranged spine, the initialization mode may be used to select one or more pairs of electrodes. The calibration operations may additionally or alternatively be used to set the stimulation parameters related to how stimulation is applied such as frequency, current, duration, interval, and / or other suitable stimulation parameter.

[0096] In one particular variation, as shown in FIG. 7, performing an initialization routine of a stimulation module that determines a set of stimulation parameters can include cycling through electrode groupings S113, detecting a response in a respiratory signal for each electrode grouping S114, and determining a select electrode grouping as part of the stimulation parameters S115. Performing an initialization routine of a stimulation module that determines a set of stimulation parameters can additionally or alternatively include cycling through pacing parameters S116 and selecting stimulation parameters in the set of stimulation parameters S117. The stimulation parameters may similarly be selected based on the response in the respiratory signal and / or other sensor data.

[0097] Block S113, which includes cycling through electrode groupings, functions to test possible electrode positions. Cycling through the electrode groupings may test different pairs or groups of positive and negative electrode pairings for delivering stimulation.

[0098] When there is a circumferential array of electrodes, then cycling through the electrode groupings may cycle through different pairs or groups of electrodes at different radial positions. In some variations, this may include cycling through different circumferentially aligned electrode pairings or groups.

[0099] When the circumferential array is arranged on a set of splines, then cycling through the electrode groupings may cycle through electrode groupings on each of thesplines. When there are only two electrodes, this may include performing a test of electrode pairs for each spline.

[0100] When there are three or more electrodes on each spline, cycling through electrode grouping may test a plurality of electrode pairs or groupings for each subset of electrodes on each spline. In this way, cycling through electrode grouping may be cycling through different radial and longitudinal variations of electrode pairings or groupings.

[0101] For example, when there are 4 electrodes on a spline. It may test pairing the first electrode and third in opposite polarities, the second and fourth in opposite polarities, and the second and third in opposite polarities. Other pairings may also be tested including some or all of the different permutations of electrode groupings for pairs of two electrodes and / or groups of three or more electrodes (where two or more electrodes are both assigned the same polarity).

[0102] While cycling through electrode groupings may test electrodes in the same radial positions, it may also test radial variations with electrodes in different radial positions. For example, one electrode in a first radial orientation maybe set in one polarity (anode or cathode), and then it maybe tested being paired with three electrodes in different radial positions in the opposite polarity (cathode or anode). In some variations, this maybe used to simplify testing or to test for the stimulation module not being parallel with the tracheal lumen. In other words, this may be used to test for diagonal pairs or groupings of electrodes.

[0103] Block S114 and S115, which includes detecting a response for each electrode grouping and determining a select electrode grouping, functions to evaluate results from trying different electrode groupings and then pick a subset of electrodes that are positioned for a desired response. Detecting the response may be used to monitor the patient for different physiological effects that may indicate a positive result (stimulating a targeted region of the phrenic nerve) or a negative result (stimulating a region that maybe desirable to avoid). Accordingly, determining the select electrode grouping may include selecting the select electrode grouping based on which electrode grouping triggers a detected respiratory response.

[0104] In some variations, one monitored response may be changes in airway pressure, flow rate, and / or muscular activation measured through a sensor system. Using the same stimulation parameters for different pairs of electrodes may result in different changes in airway flow. In one example stimulating pairs 3 and 6 from FIG. 3A may see no change in airway flow (e.g., no diaphragm movement), while stimulating pairs 2 and 5 could see significant airway flow due to diaphragm movement.

[0105] Detecting a response may including monitoring for a respiratory effect. Detecting a response in the respiratory signal may include identifying a pattern indicative of diaphragm contraction. The diaphragm contraction maybe identified as meeting conditions for targeted contraction such being smooth, synchronized, and / or otherwise characteristic of a controlled healthy respiratory contraction.

[0106] Various signal processing rules or heuristics, a data classifier model, or other suitable data analysis process may be used to automatically detect, score, or otherwise characterize a respiratory response for the monitored signals. This may enable ranking or comparing different electrode groupings and / or stimulation parameters. In addition to positive / desired responses, analysis may also detect or evaluate a response for negative aspects. Negative results such as stimulation of a vagus nerve maybe detected by detecting perturbance of heart rate.

[0107] The method may additionally include reading a respiratory signal and / or other sensor signal for use in monitoring a respiratory effect.

[0108] In one variation, the ventilator may alternatively be sensed using a respiratory sensor that is integrated with an ETT or ventilatory circuit (e.g., a pressure sensor or flow sensor integrated with an ETT, airway access device, or MV tubing).

[0109] In another variation, the reading a respiratory signal may include reading a ventilator signal. This signal maybe a data signal directly from a ventilator.

[0110] In such variations, the method can include reading a ventilator signal (directly or indirectly through some respiratory sensor) and then, as part of detecting the response in the respiratory signal, analyzing the ventilator signal as at least part of the respiratory signal that is analyzed. In some cases, the ventilator signal may be the only data used for analysis. In other variations, the ventilator signal data maybe combinedwith other data. The ventilator data signal may be used to understand how stimulation, diaphragm contractions, and ventilation are interacting.

[0111] In another variation, one or more sensors may be used for sensing or otherwise monitoring respiration or physiological state of a subject such as using a pressure sensor, a flow sensor, an accelerometer, an external camera monitoring a patient, a heart rate monitoring device (e.g., an ECG), a muscle electromyography (EMG) sensor, an accelerometer, and / or other sensing systems.

[0112] In such variations, the method may include reading or sensing a respiratory sensor signal, which maybe from one of the sensors described herein which characterize respiration or state of a subject related to respiration. In such a variation, detecting the response in the respiratory signal may include analyzing the respiratory sensor signal as at least part of the respiratory signal. For example, EMG, accelerometer, or visual data may be used to model characteristics of respiration.

[0113] When cycling through electrode grouping in S113 and / or cycling through stimulation parameters S116, the respiratory and / or ventilation signals maybe used to in conducting test stimulation cycles. The respiratory signal maybe used to determine timing, flow, pressure information which may be used in synchronizing stimulation with phases of respiration or ventilation, such as synchronizing stimulation to inspiratory phases. Synchronizing to the respiratory or ventilation signals may similarly be performed during stimulation using the selected stimulation parameters with the select electrode grouping.

[0114] At least one pair of electrodes maybe determined to be positioned appropriately for stimulation. Multiple electrode pairs may be used to stimulate multiple regions. For stimulating the phrenic nerve with a tracheal phrenic nerve stimulation device, stimulation may be applied to the phrenic nerves which in theory would be approximately on opposing sides of the trachea. Accordingly, two pairs of electrodes maybe selected for targeting stimulation towards the phrenic nerves on differing sides. In a theoretical example the electrode groups would include two pairs of electrodes on opposing sides of the stimulation module. Anatomy will vary, however, causing nerves to not always be aligned exactly on opposing sides. Similarly, relativepositioning of the electrode system may not always be aligned. Selection of the electrodes can dynamically adjust to these variations.

[0115] Additionally, multiple electrode pairings may be used in combination for stimulation in one region. For example, the phrenic nerve maybe positioned between two different electrode pairs. Accordingly, both of the two electrode pairs maybe used simultaneously or in combination such that the induced electric field may be more focused around the targeted phrenic nerve.

[0116] Block S116 and S117, which includes cycling through stimulation parameters and selecting stimulation parameters in the set of stimulation parameters, functions to determine the stimulation properties used when applying stimulation. In particular, this may be used for testing and determining electrical stimulation pacing parameters for stimulation. As such, performing an initialization routine of blocks S116 and S117 may include cycling through pacing parameters and selecting stimulation parameters in the set of stimulation parameters. This testing and determination of electrical stimulation properties maybe performed concurrent, a separate process, or independently from with blocks S113, S114, and S115.

[0117] When cycling through stimulation parameters, different stimulation parameters such as frequency, current, duration, and / or interval maybe varied for different instances of test stimulations. Other variables may include but are not limited to voltage, pulse width, interphase delay, pulse type (e.g., square, triangular, monophasic, biphasic, trapezoidal, or ramped profiles), gaussian width, on time, ramp on time, and / or ramp off time. Results of the test stimulations can be monitored and used in selecting stimulation parameters with desired results.

[0118] As one example of an initialization routine that includes cycling through electrode groupings, functions to test possible electrode positions S113, detecting a response for each electrode grouping S114, determining a select electrode grouping S115, cycling through stimulation parameters S116 and selecting stimulation parameters in the set of stimulation parameters S117 may involve testing electrode groupings and then optimizing / enhancing stimulation parameters for selected electrodes. This process maybe based on finding stimulation parameters that improve the respiration signals (such as reducing peak pressure during MV).

[0119] When testing electrode groupings, a set of baseline stimulation parameters is selected. The baseline will generally stimulation parameters known or expected to work from previous testing. Then different pairs are selected and tested by applying stimulation. The signals measured by the sensor system may then be monitored for any changes. For example, pressure maybe monitored. Each pair or combination of electrodes maybe tested individually. In some cases, an alternative approach to electrode grouping maybe used. For example a single electrode maybe used as one polarity (e.g., a positive electrode) and then the other electrodes of the opposing polarity (e.g., negative electrodes) maybe changed for each tested electrode pairing. A pair or grouping of electrodes may be selected based on which one shows the best impact on the monitored signals. For example, the electrode pair with the biggest change in airway pressure maybe selected. Then with that electrode pair selected, the stimulation parameters may be varied to determine customized stimulation parameters.

[0120] Block S120, which includes operating a stimulation module using the set of stimulation parameters, functions to generate electric fields for stimulation. The stimulation will preferably be applied using the various parameters determined through block S110. This may include using a subset of electrodes as determined through blocks S113, S114, and S115. Additionally or alternatively, other stimulation parameters such as frequency, duration, current, and interval, and / or other parameters such as pulse waveform shape, pulse width, on-time duration, or ramp time determined through blocks S116 and S117, maybe used for stimulation. In some variations, operating the stimulation module may include repeated calibration testing to adjust the stimulation while stimulation is being applied.

[0121] When used for enhancing ventilation or respiration, operating the stimulation module using the determined stimulation parameters will preferably continue performing stimulation in a way that was found to enhance ventilation and / or respiration. As such, stimulation can maintain stimulation in synchronization with the respiratory signal(s) that were measured and used for S110. Accordingly, operating the stimulation module using the set of stimulation parameters may include activating stimulation of the select electrode grouping in synchronization with a rhythm of inspiration as indicated by the respiration signal (e.g., a ventilator signal and / or otherrespiration sensed signal). Alignment to the respiration signal may have already been calibrated in block Sno, but performing stimulation using the stimulation parameters may maintain phase alignment to inspiration and / or expiration phases of respiration.

[0122] In some variations, the method may include a process by which stimulation may be recalibrated. Recalibration may function to account for changes in stimulation module positioning or changes to a subject’s response to stimulation. For example, movement by a subject or by a professional manipulating the stimulation module may cause the relative orientation of the targeted nerve and the stimulation module to change. This can impact the efficacy of the stimulation and so recalibration can restore electrode targeting and effective stimulation.

[0123] In one variation, recalibration may be performed routinely. For example, the method may repeat S110 and S120 periodically. For example, every hour may recalibrate. In some cases, to avoid a full recalibration cycle, recalibration may be partially performed. For example, after an initial calibration in S110, partial recalibration may test small variations close to the current stimulation parameters.

[0124] In some variations, recalibration may be performed in response to user input. For example, the stimulation system may receive a user input trigger that causes recalibration for repeating S110 and then restarting S120 with updated stimulation parameters.

[0125] In some variations, recalibration may be performed dynamically in response to monitored state. The method may detect a change in a subject’s respiratory response to stimulation and adjust the stimulation parameters in response to the change with a goal or restoring enhanced directional targeting and / or electrical stimulation properties. As such, the method may include: monitoring one or more measured signals from a respiratory sensor or ventilator and determining, based on the measured signals, a change in respiratory response to stimulation S132; and in response to determining the change, performing the initialization routine to update the set of stimulation parameters S134 as shown in FIG. 8. The measured signals may include the respiratory signals discussed herein or any other data signal. This dynamic recalibration may function to adapt to changes in electrode-tissue connection. The determined change maybedetected by detecting a change in response to stimulation. For example if stimulation efficacy declines then recalibration may help improve efficacy.5. System Architecture

[0126] The systems and methods of the embodiments can be embodied and / or implemented at least in part as a machine configured to receive a computer-readable medium storing computer-readable instructions. The instructions can be executed by computer-executable components integrated with the application, applet, host, server, network, website, communication service, communication interface, hardware / firm ware / software elements of a user computer or mobile device, wristband, smartphone, or any suitable combination thereof. Other systems and methods of the embodiment can be embodied and / or implemented at least in part as a machine configured to receive a computer-readable medium storing computer-readable instructions. The instructions can be executed by computer-executable components integrated with apparatuses and networks of the type described above. The computer- readable medium can be stored on any suitable computer readable media such as RAMs, ROMs, flash memory, EEPROMs, optical devices (CD or DVD), hard drives, floppy drives, or any suitable device. The computer-executable component can be a processor, but any suitable dedicated hardware device can (alternatively or additionally) execute the instructions.

[0127] In one variation, a system comprising of one or more computer-readable mediums (e.g., non-transitory computer-readable mediums) storing instructions that, when executed by the one or more computer processors, cause a computing platform to perform operations comprising those of the system or method described herein such as: performing an initialization routine that determines a set of stimulation parameters and operating a stimulation module using the set of stimulation parameters.

[0128] FIGURE 9 is an exemplary computer architecture diagram of one implementation of the system. In some implementations, the system is implemented in a plurality of devices in communication over a communication channel and / or network. In some implementations, the elements of the system are implemented in separate computing devices. In some implementations, two or more of the system elements areimplemented in same devices. The system and portions of the system may be integrated into a computing device or system that can serve as or within the system.

[0129] The communication channel 1001 interfaces with the processors 1002A- 1002N, the memory (e.g., a random-access memory (RAM)) 1003, a read only memory (ROM) 1004, a processor-readable storage medium 1005, a display device 1006, a user input device 1007, and a network device 1008. As shown, the computer infrastructure maybe used in connecting stimulation module 1101, sensor system 1102, control system 1103, and / or other suitable computing devices.

[0130] The processors 1002A-1002N may take many forms, such CPUs (Central Processing Units), GPUs (Graphical Processing Units), microprocessors, ML / DL (Machine Learning / Deep Learning) processing units such as a Tensor Processing Unit, FPGA (Field Programmable Gate Arrays, custom processors, and / or any suitable type of processor.

[0131] The processors 1002A-1002N and the main memory 1003 (or some subcombination) can form a processing unit 1010. In some embodiments, the processing unit includes one or more processors communicatively coupled to one or more of a RAM, ROM, and machine-readable storage medium; the one or more processors of the processing unit receive instructions stored by the one or more of a RAM, ROM, and machine-readable storage medium via a bus; and the one or more processors execute the received instructions. In some embodiments, the processing unit is an ASIC (Application-Specific Integrated Circuit). In some embodiments, the processing unit is a SoC (System-on-Chip). In some embodiments, the processing unit includes one or more of the elements of the system.

[0132] A network device 1008 may provide one or more wired or wireless interfaces for exchanging data and commands between the system and / or other devices, such as devices of external systems. Such wired and wireless interfaces include, for example, a universal serial bus (USB) interface, Bluetooth interface, Wi-Fi interface, Ethernet interface, near field communication (NFC) interface, and the like.

[0133] Computer and / or Machine-readable executable instructions comprising of configuration for software programs (such as an operating system, applicationprograms, and device drivers) can be stored in the memory 1003 from the processor- readable storage medium 1005, the ROM 1004 or any other data storage system.

[0134] When executed by one or more computer processors, the respective machineexecutable instructions maybe accessed by at least one of processors 1002A-1002N (of a processing unit 1010) via the communication channel 1001, and then executed by at least one of processors 1001A-1001N. Data, databases, data records or other stored forms data created or used by the software programs can also be stored in the memory 1003, and such data is accessed by at least one of processors 1002A-1002N during execution of the machine-executable instructions of the software programs.

[0135] The processor-readable storage medium 1005 is one of (or a combination of two or more of) a hard drive, a flash drive, a DVD, a CD, an optical disk, a floppy disk, a flash storage, a solid-state drive, a ROM, an EEPROM, an electronic circuit, a semiconductor memory device, and the like. The processor-readable storage medium 1005 can include an operating system, software programs, device drivers, and / or other suitable sub-systems or software.

[0136] As used herein, first, second, third, etc. are used to characterize and distinguish various elements, components, regions, layers and / or sections. These elements, components, regions, layers and / or sections should not be limited by these terms. Use of numerical terms may be used to distinguish one element, component, region, layer and / or section from another element, component, region, layer and / or section. Use of such numerical terms does not imply a sequence or order unless clearly indicated by the context. Such numerical references maybe used interchangeable without departing from the teaching of the embodiments and variations herein.

[0137] As a person skilled in the art will recognize from the previous detailed description and from the figures and claims, modifications and changes can be made to the embodiments of the invention without departing from the scope of this invention as defined in the following claims.

Claims

CLAIMSWe Claim:

1. A method for operating a tracheal nerve stimulation device comprising: performing an initialization routine of a stimulation module that determines a set of stimulation parameters, the initialization routine comprising: cycling through electrode groupings, detecting a response in a respiratory signal for each electrode grouping, and determining a select electrode grouping as part of the stimulation parameters; and operating the stimulation module using the set of stimulation parameters.

2. The method of claim 1, wherein determining the select electrode grouping comprises selecting the select electrode grouping based on which electrode grouping triggers a detected respiratory response.

3. The method of claim 1, wherein detecting a response in the respiratory signal comprises identifying a pattern indicative of diaphragm contraction.

4. The method of claim 3, further comprising reading a ventilator signal; and wherein detecting the response in the respiratory signal comprises analyzing the ventilator signal as at least part of the respiratory signal.

5. The method of claim 4, wherein operating the stimulation module using the set of stimulation parameters comprises activating stimulation of the select electrode grouping in synchronization with a rhythm of inspiration as indicated by the ventilator signal.

6. The method of claim 3, further comprising reading a respiratory sensor signal; and wherein detecting a response in the respiratory signal comprises analyzing the respiratory sensor signal as at least part of the respiratory signal.

7. The method of claim 1, further comprising initially deploying the stimulation module at a distal end of an endotracheal tube; and wherein performing the initialization routine is performed subsequent to deployment of the stimulation module8. The method of claim 1, wherein performing an initialization routine further comprises cycling through pacing parameters and selecting stimulation parameters in the set of stimulation parameters.

9. The method of claim 1, wherein the stimulation module comprises a set of electrodes configured as a circumferential array, wherein subsets of the set of electrodes are selectable for stimulation in different radial orientations.

10. The method of claim 9, wherein determining the select electrode grouping comprises selecting electrodes positioned along one radial orientation of the stimulation module11. The method of claim 1, wherein the stimulation parameters include at least one of: pulse waveform shape, pulse width, on-time duration, or ramp time.

12. The method of claim 1, further comprising: monitoring one or more measured signals from a respiratory sensor or ventilator; determining, based on the measured signals, a change in respiratory response to stimulation; and in response to determining the change, performing the initialization routine to update the set of stimulation parameters.

13. A system comprising a stimulation module comprising a set of flexible splines; a set of electrodes, wherein a subset of electrodes is positioned on each spline of the set of flexible splines; a stimulation control system, conductively connected to the set of electrodes, the stimulation control system comprising configuration to selectably control a stimulation state of electrode subgroups in the set of electrodes.

14. The system of claim 13, the stimulation control system further comprising an interface to a respiratory signal.

15. The system of claim 14, wherein the interface to the respiratory signal system comprises an interface with a mechanical ventilator and is configured to receive a ventilator signal indicating an inspiratory phase.

16. The system of claim 14, wherein the respiratory signal system comprises at least one sensor selected from the group consisting of a pressure sensor, a flow sensor, an electromyography sensor, and an accelerometer.

17. The system of claim 13, wherein the stimulation control system is configured to selectably activate or deactivate electrode subgroups of the set of electrodes18. The system of claim 13, wherein the stimulation module is collapsible during delivery and configured to expand radially within the trachea during deployment.

19. The system of claim 13, wherein the flexible splines are connected at a proximal end and configured to arc outward such that a circumferential spread increases along a distal direction, and wherein each spline comprises at least two electrodes.

20. The system of claim 13, wherein the flexible splines are formed from a flexible printed circuit board substrate.

21. The system of claim 13, wherein the set of electrodes are formed from a platinumiridium alloy.

Images