WO2026006697A1 - Intelligent catheter system - Google Patents

Abstract

A catheter system includes a catheter, a fiber optic sensor assembly, and a processing unit. The catheter may be configured for placement within a digestive tract of a patient. The fiber optic sensor assembly may be configured to sense two or more characteristics along at least a subsection of the catheter. The two or more characteristics may be selected from the group consisting of: a shape of the catheter, pressure, strain, vibration, and temperature. The fiber optic sensor assembly senses the two or more characteristics and transmits signals related to the two or more characteristics to the processing unit. The processing unit is configured to detect a location of the catheter in a patient's body relative to human anatomy, physiological conditions in a vicinity of the catheter, and/or physiological parameters of the patient's body based on the signals received from the fiber optic assembly.

Description

INTELLIGENT CATHETER SYSTEM CROSS-REFERENCE TO RELATED APPLICATION [0001] This application claims the benefit of U.S. Provisional Application No.63/665,313, filed June 28, 2024, the contents of which are incorporated herein by reference in its entirety. FIELD OF THE DISCLOSURE [0002] The subject matter of the present disclosure relates generally to an intelligent catheter system with multimodal sensing capability. BACKGROUND [0003] Physicians and other health care providers frequently use catheters to treat patients. The known catheters include a tube which is inserted into the human body. Certain catheters are inserted through the patient’s nose or mouth for treating the gastrointestinal (GI) tract. These catheters, sometimes known as enteral catheters, typically include feeding tubes. The feeding tube lies in the stomach or intestines, and a feeding bag delivers liquid nutrient, liquid medicine or a combination of the two to the patient. [0004] Other types of catheters are inserted into the patient’s veins or arteries for treating the cardiovascular system. These intravascular catheters include, among others, central venous catheters, peripheral venous catheters and the peripherally inserted central catheters. These catheters include a relatively small tube that passes through the patient’s veins or arteries. Depending on the application, the health care provider can use an intravascular catheter to remove blood vessel blockages, place inserts into blood vessels and provide patients with injections of medications, drugs, fluids, nutrients, or blood products over a period of time, sometimes several weeks or more. [0005] When using these known enteral and intravascular catheters, it is important to place the end of the catheter at the proper location within the human body. Erroneous placement of the catheter tip may injure or harm the patient. For example, if the health care provider erroneously or inadvertently places an enteral catheter into the patient’s lungs, liquid may be introduced into the lungs with harmful results. If this scenario is undetected this can lead to serious patient harm or even death. If the health care provider erroneously places an intravascular catheter into the wrong blood vessel of the cardiovascular system, the patient may experience infection, injury or a harmful blockage. [0006] With feeding tubes in particular, it is also prudent to check that the exit aperture of the feeding tube (typically located at the distal end/tip of the tube) remains in its desired location over the period of treatment, e.g., feeding. Protocols that address this requirement in enteral feeding tubes include frequent monitoring for the appropriate pH of fluids extracted from the feeding tube when not carrying nutritional liquids and careful patient monitoring to ensure nutritional uptake is as expected. Moreover, there are nutrition management related risks of either delivering inadequate or excess nutrition or medications that may be life-sustaining or become toxic or may lead to regurgitation and aspiration. [0007] In some cases, health care providers use X-ray machines to gather information about the location of catheters within the body. There are several disadvantages with using X-ray machines. For example, these machines are relatively large and heavy, consume a relatively large amount of energy and expose the patient to a relatively high degree of X-ray radiation. Also, these machines are typically not readily accessible for use because, due to their size, they are usually installed in a special X-ray room. This room can be far away from the patient’s room. Therefore, health care providers can find it inconvenient to use these machines for performing catheter insertion procedures. Furthermore, it can be inconvenient to transport these machines to a patient’s home for home care catheter procedures. Moreover, even X-rays are not necessarily conclusive as to the location of the catheter tip, as the natural and continuous movement of the internal organs can make it difficult for the physician interpreting the X-ray to be sure of the actual location of the distal end of the catheter. [0008] Another existing catheter locating means involves using an electromagnetic coil positioned inside the catheter and an electromagnetic coil locating receiver outside of the patient’s body. The electromagnetic coil is generally incorporated into a stylet or guide wire which is inserted within the catheter. The coil locating receiver can be used to determine the distance the coil is from the receiver and its depth in the patient’s body and can communicate with a display to show a reference image of a non-subject body and an image of the coil located on the display with the reference image. However, these systems also have several disadvantages. For example, the coil locating receiver is a large device that must rest in a precise location outside the patient’s body and does not permit for adjustments due to each individual patient’s anatomical size or shape. However, a patient undergoing a feeding tube placement will be agitated and sudden movements are expected, which can move the coil locating receiver, thus increasing the likelihood of positional errors or complications in locating the catheter. Additionally, these existing systems can only display the coil location over a reference image of a non-subject (i.e., a generic patient) body without reference to the individual patient’s particular anatomy. Therefore, health care providers can estimate the positioning of the catheter using the electromagnetic coil and coil locating receiver but cannot estimate or view the specific patient’s anatomy. [0009] Consequently, there is a need for a catheter system having improved sensing capabilities. In particular, an intelligent catheter system having multimodal sensing capability integrated into the catheter would be advantageous. SUMMARY [0010] Objects and advantages of the invention will be set forth in part in the following description, or may be obvious from the description, or may be learned through practice of the invention. [0011] In some implementations, a tubing assembly is provided. The tubing assembly can include: a catheter having a proximal end and a distal end and extending in a longitudinal direction, the catheter having a wall extending from the proximal end to the distal end, the catheter wall defining a lumen therein, and wherein the catheter is configured for placement within a digestive tract of a patient; and a fiber optic sensor assembly, the fiber optic sensor assembly being configured to sense two or more characteristics along at least a subsection of the catheter, the two or more characteristics selected from the group consisting of: a shape of the catheter, pressure, strain, vibration, and temperature. [0012] In some implementations, the fiber optic sensor assembly includes at least one fiber optic sensor disposed in the catheter wall. [0013] In some implementations, the fiber optic sensor assembly includes at least one fiber optic sensor extending within the lumen of the catheter. [0014] In some implementations, the fiber optic sensor assembly includes a plurality of spatially distributed sensors. [0015] In some implementations, the plurality of spatially distributed sensors are spatially distributed in the longitudinal direction of the catheter. [0016] In some implementations, the plurality of spatially distributed sensors are spatially distributed about the lumen of the catheter. [0017] In some implementations, the fiber optic sensor assembly includes at least one single core fiber optic cable. [0018] In some implementations, the fiber optic sensor assembly includes a multi-core fiber optic cable. [0019] In some implementations, the tubing assembly includes a removable stylet insertable in the lumen of the catheter, wherein the multi-core fiber optic cable is integrated in the stylet. [0020] In some implementations, a catheter system is provided. The catheter system can include: a catheter having a proximal end and a distal end and extending in a longitudinal direction, the catheter having a wall extending from the proximal end to the distal end, the catheter wall defining a lumen therein, and wherein the catheter is configured for placement within a digestive tract of a patient; a fiber optic sensor assembly, the fiber optic sensor assembly being configured to sense two or more characteristics along at least a subsection of the catheter, the two or more characteristics selected from the group consisting of: a shape of the catheter, pressure, strain, vibration, and temperature; and a processor; wherein the fiber optic sensor assembly senses the two or more characteristics and transmits signals related to the two or more characteristics to the processor; wherein the processor is configured to detect a location of the catheter in a patient's body relative to human anatomy, physiological conditions in a vicinity of the catheter, physiological parameters of the patient's body, and/or externally induced physiological conditions based on the signals received from the fiber optic assembly. [0021] In some implementations, human anatomy includes three-dimensional (3D) curves that represent either airway or gastrointestinal (GI) passage. [0022] In some implementations, the physiological conditions include characteristics of esophago-gastro-jejunal motility, esophago-gastro-jejunal contents, reflux, swallow, gag, and/or cough movements to aid in nutritional management and/or diagnoses and monitoring of gastrointestinal health. [0023] In some implementations, the physiological parameters include body temperature, heart rate, respiration rate, and peristalsis of gastrointestinal subsystems. [0024] In some implementations, the physiological parameters are configured to be used by the processor to derive the patient's metabolic rate and nutrient absorption. [0025] In some implementations, the externally induced physiological conditions include swallowing water, stomach palpation, inducing puffs of air. [0026] In some implementations, the fiber optic sensor assembly and the processor are configured to sense at least one of the two or more characteristics using Fiber Bragg Grating. [0027] In some implementations, the fiber optic sensor assembly and the processor are configured to sense at least one of the two or more characteristics using Raman scattering, Rayleigh scattering, and/or Brillouin scattering. [0028] In some implementations, the fiber optic sensor assembly includes a plurality of spatially distributed sensors, wherein the plurality of spatially distributed sensors are either spatially or time multiplexed. [0029] In some implementations, a method for using a catheter system is provided. The method can include: placing the catheter system within a digestive tract of a patient, the catheter system having a proximal end and a distal end and extending in a longitudinal direction, the catheter having a wall extending from the proximal end to the distal end, the catheter wall defining a lumen therein; sensing, using a fiber optic sensor assembly, two or more characteristics along at least a subsection of the catheter, the two or more characteristics selected from the group consisting of: a shape of the catheter, pressure, strain, vibration, and temperature; transmitting signals related to the two or more characteristics to a processor; and detecting, by the processor, a location of the catheter in a patient's body relative to human anatomy, physiological conditions in a vicinity of the catheter, physiological parameters of the patient's body, and/or externally induced physiological conditions based on the signals received from the fiber optic assembly determining, by the processor and based, at least in part on the physiological parameters, the patient's metabolic rate and/or nutrient absorption. [0030] In some implementations, sensing the two or more characteristics along at least a subsection of the catheter includes using Fiber Bragg Grating, Raman scattering, Rayleigh scattering, and/or Brillouin scattering. [0031] These and other features, aspects, and advantages of the present disclosure will become better understood with reference to the following description and appended claims. The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate implementations of the disclosure and, together with the description, serve to explain the principles of the disclosure. BRIEF DESCRIPTION OF THE DRAWINGS [0032] A full and enabling disclosure of the present disclosure, including the best mode thereof, directed to one of ordinary skill in the art, is set forth in the specification, which makes reference to the appended figures, in which: [0033] FIG.1 illustrates a side view of a tubing assembly in accordance with embodiments of the present disclosure; [0034] FIG.2 illustrates a cross-sectional view of a tubing assembly in accordance with embodiments of the present disclosure; [0035] FIG.3 illustrates a cross-sectional view of a tubing assembly in accordance with embodiments of the present disclosure; [0036] FIG.4 illustrates a side view of a tubing assembly in accordance with embodiments of the present disclosure; [0037] FIG.5 illustrates a schematic representation of a fiber optic sensor assembly in accordance with embodiments of the present disclosure; [0038] FIG.6 illustrates a schematic representation of a fiber optic sensor assembly having spatially distributed sensors in accordance with embodiments of the present disclosure; [0039] FIG.7 illustrates a schematic representation of an electronic catheter unit in accordance with embodiments of the present disclosure; [0040] FIG.8 illustrates a flow chart of a method of using the intelligent catheter system in accordance with embodiments of the present disclosure; [0041] FIG.9 illustrates a flow chart of a method of using the intelligent catheter system in accordance with embodiments of the present disclosure; [0042] FIG.10 illustrates a flow chart of a method of using the intelligent catheter system in accordance with embodiments of the present disclosure; [0043] FIG.11 illustrates a flow chart of a method of using the intelligent catheter system in accordance with embodiments of the present disclosure. DETAILED DESCRIPTION [0044] Reference now will be made in detail to embodiments of the invention, one or more examples of which are illustrated in the drawings. Each example is provided by way of explanation of the invention, not limitation of the invention. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made in the present disclosure without departing from the scope or spirit of the invention. For instance, features illustrated or described as part of one embodiment can be used with another embodiment to yield a still further embodiment. Thus, it is intended that the present disclosure covers such modifications and variations as come within the scope of the appended claims and their equivalents. The detailed description uses numerical and letter designations to refer to features in the drawings. Like or similar designations in the drawings and description have been used to refer to like or similar parts of the invention. [0045] As used herein, the terms “first”, “second”, and “third” may be used interchangeably to distinguish one component from another and are not intended to signify location or importance of the individual components. The singular forms “a,” “an,” and “the” include plural references unless the context clearly dictates otherwise. The terms “coupled,” “fixed,” “attached to,” and the like refer to both direct coupling, fixing, or attaching, as well as indirect coupling, fixing, or attaching through one or more intermediate components or features, unless otherwise specified herein. As used herein, the terms “comprises,” “comprising,” “includes,” “including,” “has,” “having” or any other variation thereof, are intended to cover a non-exclusive inclusion. For example, a process, method, article, or apparatus that comprises a list of features is not necessarily limited only to those features but may include other features not expressly listed or inherent to such process, method, article, or apparatus. Further, unless expressly stated to the contrary, “or” refers to an inclusive- or and not to an exclusive- or. For example, a condition A or B is satisfied by any one of the following: A is true (or present) and B is false (or not present), A is false (or not present) and B is true (or present), and both A and B are true (or present). [0046] Terms of approximation, such as “about,” “generally,” “approximately,” or “substantially,” include values within ten percent greater or less than the stated value. When used in the context of an angle or direction, such terms include within ten degrees greater or less than the stated angle or direction. For example, “generally vertical” includes directions within ten degrees of vertical in any direction, e.g., clockwise or counter-clockwise. Further, when a plurality of ranges are provided, any combination of a minimum value and a maximum value described in the plurality of ranges are contemplated by the present disclosure. For example, if ranges of “from about 20% to about 80%” and “from about 30% to about 70%” are described, a range of “from about 20% to about 70%” or a range of “from about 30% to about 80%” are also contemplated by the present disclosure. [0047] Generally speaking, the present disclosure is directed to a tubing assembly and an electronic intelligent catheter unit including a catheter (referred to herein as part of a tubing assembly and/or comprising a tube) and a fiber optic sensor assembly. The fiber optic sensor assembly is configured to sense two or more characteristics along at least a subsection of the catheter. The two or more characteristics are selected from the group consisting of: a shape of the catheter, pressure, strain, vibration, and temperature. The intelligent catheter system or unit receives signals from the sensors and utilizes multi-modal sensor input, e.g., from two or more sensing modalities, to determine catheter placement, anatomical references, diagnostic patient information, and other characteristics. The present inventors have found that combining input from multiple sensing modalities, which can be sensed using a single fiber optic sensing assembly, enable superior catheter placement detection and enable detection of physiological characteristics as compared to existing enteral feeding sensing solutions. The specific features of the intelligent catheter system of the present disclosure may be better understood with reference to FIGS.1-11. [0048] Referring now to FIG.1, one embodiment of a tubing assembly 10 is shown. The tubing assembly 10 includes a catheter 12 and a fiber optic sensor assembly 14. The catheter 12 includes a tube 16 extending from a proximal end 18 to a distal end 20. The tube 16 is formed by a tube wall 22 having an outer surface 24 and an inner surface 26. The inner surface 26 surrounds a lumen 28 of the catheter 12. The catheter 12 may include one or more openings 30 at the distal end 20 communicating with the lumen 28. For instance, when the catheter is used as a nasogastric tube, the lumen 28 is configured to channel the flow of fluid from an external source to a patient’s stomach. In various implementation, the catheter 12 and fiber optic sensor assembly 14 define a unitary body or may be operatively and/or removably coupled to one another. [0049] The tube 16 of the catheter 12 can be formed from a variety of materials, giving due consideration to the goals of flexibility, lightweight, strength, smoothness, and non-reactivity to anatomical systems, i.e., safety. Suitable materials for the first tube 16 include polyolefins, including polyethylene and polypropylene, polyamides, polyimides, Teflon® (polytetrafluoroethylene), polyesters, polyurethanes, any copolymers thereof, and other materials known in the art. [0050] Still referring to FIG.1, the fiber optic sensor assembly 14 is illustrated as part of the tubing assembly 10. The fiber optic sensor assembly 14 includes at least one sensor 50. The sensor 50 is incorporated into at least one fiber optic cable 52 that extends along the tube 16. For instance, the at least one fiber optic cable 52 may extend along an entire length of the tube 16 from the proximal end 18 to the distal end 20, or may extend along a length from the proximal end 18 to a medial point along the tube 16 that is proximal to the distal end 20. This disclosure contemplates that each sensor 50 can be or comprise at least one of a shape sensor 70, pressure sensor 72, strain sensor 74, temperature sensor 76, vibration sensor 78, imaging sensor, opto-chemical sensor 82, and/or the like, as discussed in more detail below. In some implementations, the above-noted sensors 70, 72, 74, 76, 78, 82 can be positioned elsewhere and can be part of or separate from the fiber optic sensor assembly 14 and/or tubing assembly 10. [0051] In some implementations, as illustrated in FIGS.1 and 2, a fiber optic cable 52 may be integrated with the tube wall 22. For instance, the fiber optic cable 52 may be disposed between the outer surface 24 and inner surface 26 of the tube wall 22. The fiber optic cable 52 may additionally or alternatively be formed along the outer surface 24 or inner surface 26 of the tube wall 22. [0052] A fiber optic cable 52 may be a single core fiber optic cable 54 or a multi-core fiber optic cable 56. A multi-core fiber optic cable 56 may include a plurality of single-core optical fibers 58 integrated into cable 56 by a cable housing 60. Either a single-core fiber optic cable 54 or multi-core fiber optic cable 56 may be integrated with the tube wall 22 as described above. [0053] In some implementations, as illustrated in FIG.2, the at least one fiber optic cable 52 may extend within the lumen 28 of the tube 16. For instance, a stylet 62 may integrate a fiber optic cable therein. For instance, a multi-core fiber optic cable 56 may be formed with a cable housing 60 configured to form a stylet 62 having sufficient stiffness to assist with guiding insertion of the catheter 12 into a patient’s body. The multi-core fiber optic cable 56 may form the stylet 62 on its own, or the stylet 62 may include a stylet body 64 that integrates one or more fiber-optic cables 52 therein. [0054] As shown in FIGS.1 and 2, the fiber optic cable(s) 52 may extend longitudinally along the tube 16 in a straight manner. Additionally or alternatively, as shown in FIG.4, one or more fiber optic cable(s) 52 may extend helically along the tube 16. Moreover, in some aspects of the invention, the fiber optic cable(s) may be radially distributed relative to the tube 16. For instance, FIG.2 illustrates a multi-core fiber optic cable 56 disposed within the lumen 28 and radially distributed from the fiber optic cables 52 integrated with the tube wall 22. [0055] The fiber optic sensor assembly 14 is configured to provide multi-modal sensing (i.e., using two or more sensing modalities) of characteristics of the tube 16 and/or environment surrounding the tube 16. For instance, each fiber optic cable 52 may include one or more of a shape sensor 70, a pressure sensor 72, a strain sensor 74, a temperature sensor 76, a vibration sensor 78, an imaging sensor 80 (e.g., video feed), an opto-chemical sensor 82 (e.g., absorption, fluorescence, Fiber Bragg Gratings (FBG), or Raman spectroscopy-based), an optical sensor 84 (e.g., tip illumination). Each optical fiber 52 is configured to provide spatially distributed sensing. In this manner, each type of sensor described above may be spatially (i.e., distance) and/or time multiplexed. Time multiplexed fiber optic-based sensing uses time division multiplexing techniques to evaluate signals obtained via a plurality of fibers. A unique time slot is allotted to each of a plurality of sensors to facilitate sequential and/or simultaneous signal acquisition. Light pulses are transmitted through each of the plurality of fibers and a reflected signal corresponding with various sensors are detected at different time instances in a manner that enables signal acquisition from each sensor. In one implementation, using a single fiber with multiple sensors reduces overall system complexity and provides spatially resolved sensing capability. [0056] The fiber optic sensor assembly 14 may be configured for sensing using Fiber Bragg Gratings (FBG) technology. For instance, a plurality of optical sensors along a single fiber may monitor strain, pressure, shape, and/or temperature. In some aspects, strain, pressure, shape, and/or temperature may be distributed along a single optical fiber. In some aspects, each pressure, strain, temperature and shape sensor may be enumerated and may have a known location along the tube 16. [0057] For instance, the fiber optic sensor assembly 14 may include a multi-core fiber optic cable 56 in which each of the single-core optical fibers 58 is configured to sense strain. Collectively, the strain sensing of each of the optical fibers 58 of the multi-core fiber optic cable 56 may enable the fiber optic sensor assembly to sense the shape, e.g., curvature, of the multi-core fiber optic cable 56. In this manner, when the multi-core fiber optic cable 56 is integrated with the tube wall 22 or inserted within the lumen 28, the shape and curvature of the tube 16 may be sensed. [0058] The fiber optic sensor assembly 14 may be configured for sensing using Raman scattering, Rayleigh scattering, or Brillouin scattering. For instance, a plurality of optical sensors 50 may be spatially distributed and may monitor strain, pressure, shape, and/or temperature. In some aspects, strain, pressure, shape, and/or temperature may be distributed along a single optical fiber. In other aspects, strain, pressure, shape, and/or temperature may be distributed on separate optical cables 52. [0059] In some implementations, the fiber optic sensor assembly 14 may be implemented to perform differential pressure and/or strain measurement at different points along the length and/or circumference of the tube 16. For instance, circumferential pressure and/or strain measurement may be desired. In some aspects, two or more individual optical fibers 52 may be spaced about the circumference of the tube 16 equidistantly, for example, as illustrated in FIG. 3. Additionally or alternatively, circumferential pressure and/or strain measurement may be performed by a single fiber optic cable 52 disposed helically about the tube 16. [0060] A temperature sensor 76 may be provided by a fiber optic cable 52 to sense the environment of the tube 16, for example, the patient’s temperature when the catheter 12 is inserted into the patient’s body. The temperature sensing may be provided by either direct contact between the temperature sensor 76 and the environment, e.g., patient’s body, or by means of a thermally conductive material located between the temperature sensor 76 and the environment. For example, biocompatible metals or unsaturated polymer resin can be integrated into the tube to thermally connect the sensor to the sensing environment. [0061] The tubing assembly 10 may be coupled with a console 102, shown in FIG.7, at a proximal end thereof to form an electronic catheter unit 100. For instance, the fiber optic sensor assembly 14 may be coupled directly with the console 102. As illustrated in FIG.5 and FIG.6, the fiber optic sensor assembly 14 includes an optical source 90 and a detector 92. Both the source 90 and the detector 92 may be electronically coupled with the console 102. The console 102 may include a processor, a memory, e.g., volatile memory and/or nonvolatile memory, generally referred to herein as a processing unit. The console 102 may include a display 110 and/or may be coupled with an external display. [0062] The console 102 may be configured to process signals received from the sensors 50 of the fiber optic sensor assembly 14 to determine characteristics related to placement of the catheter 12 relative to human anatomy, e.g., whether the catheter 12 is disposed in the digestive tract or the respiratory tract of a patient. Additionally or alternatively, console 102 may be configured to process signals received from the sensors 50 of the fiber optic sensor assembly 14 to determine characteristics related to physiological conditions in the vicinity or environment of the catheter 12 that could aid in nutritional management and/or diagnoses and monitoring of gastrointestinal health, e.g., esophago-gastro-jejunal motility, reflux, etc. Moreover, physiological parameters of a patient may be sensed and processed by the console, e.g., body temperature, heart rate, respiration rate, etc. [0063] For instance, the electronic catheter unit 100 of the present disclosure may utilize the sensors 50 to sense and determine the “catheter partition” of the catheter 12, i.e., what portion of the catheter 12 is inside a patient’s body or outside a patient’s body. When the catheter 12 is inserted into a patient’s body, a portion of the tube wall 22 is slightly pinched by the operator. One or more strain or pressure sensors 50 integrated with or within the tube 16 may sense the pressure or strain point at the location the tube wall 22 is pinched. Additionally or alternatively, catheter partition may be sensed and determined by signals received from the temperature sensor(s) 76, e.g., by comparatively sensing what portion of the catheter is at room temperature v. what portion of the catheter is at body temperature. The temperature sensor(s) 76 may also sense transient temperature and catheter partition may be determined by cyclical temperature differences indicating disposition of the catheter in the nasopharynx cavity. Additionally or alternatively, catheter partition may be determined by shape analysis. For instance, the console 102 may process the received shape signals and recognize a shape of an anatomical landmark, e.g., a recognized shape of navigation through a rigid curved body such as the nasopharynx bend. Additionally or alternatively, catheter partition may be determined by signals received from one or more pressure sensor(s) 72. For example, anatomical structures such as nasal and nasopharynx structures may exert a static pressure on the tube 16, and each anatomical reference point may exert a unique pressure. Additionally or alternatively, catheter partition may be determined by signals received from one or more strain sensor(s) 74, e.g., by strain feedback coming from resistance of catheter 12 against the nasal cavity and nasopharynx tissue. [0064] In some aspects, the electronic catheter unit 10 of the present disclosure may utilize the sensors 50 to sense and determine one or more external anatomical reference points to establish a frame of reference of the patient’s unique anatomy. For instance, a sensor 50 of the fiber optic sensor assembly 14 at an external segment of the catheter 12 may be disposed at or on a known anatomical landmark of the patient, for example, xiphoid, and/or jugular notch, and/or thyroid notch. Additionally or alternatively, the external segment of the catheter may be registered against an axis, pathway, or a plane or plurality of any combination, such as xiphoid to jugular notch, or left to right shoulder. The console 102 may receive signals related to the position of the catheter 12 and save or register the actual location of the anatomical landmark(s) for the unique patient to use as reference points during insertion and/or monitoring of catheter placement. [0065] In some aspects of the present disclosure, the processing unit may determine detected anatomical references and catheter shape based on signals received from the sensors 50 to construct and, optionally, update a representation of the patient’s anatomical structure with overlaid graphical representation of a three-dimensional (3D) pathway of the catheter 12. For instance, the representation of the anatomical structure and the pathway of the catheter 12 may be continuously updated. The display 110 may include one or more a touch screen displays and form a user interface. The display may illustrate or display the constructed and continuously updated anatomical structure with overlaid 3D pathway of the feeding tube. In some aspects, the display 110 may include a color indicator, such as an LED, to reflect status of a procedure. For instance, different color options, light intensity or duty cycle may indicate different statuses. For example, a blinking green indicator may inform the user to advance the catheter 12, a yellow indicator may indicate to the user to slow down or be cautious, a red indicator may indicate to the user to retract the catheter 12, and a solid green indicator may indicate to the user that the distal end 20 of the tube 16 has reached an intended anatomical target. [0066] In some implementations, the processor may utilize the signals received from the fiber optic sensor assembly 14 to reconstruct the patient’s anatomy and, optionally, display the patient’s anatomy on the display. For instance, the processor may include an implied reconstruction algorithm that receives the input signals from the fiber optic sensor assembly 14. The processor may monitor the shape of a subsection of the catheter 12, via the fiber optic sensor assembly 14, in real time and compare the real-time data with patient data recorded in the past, and combine the information to form a reconstruction of the patient’s anatomy and a traveled pathway trace of the distal end 20 of the catheter 12. For instance, the processor may implement simultaneous location and mapping methods to develop the travelled pathway trace. [0067] For instance, the fiber optic sensor assembly 14 may be used to measure and register a nose-ear-xiphoid (“NEX”) measurement of a patient. The processor may receive the input of the NEX measurement to estimate the patient’s internal anatomy using known clinical formulas. In some aspects, the NEX measurement may be used to estimate the patient’s internal anatomy and the nasopharynx bend may be detected using the sensor(s) as described above. [0068] In some aspects, an anatomical reference can be detected by fiber strain sensed by the fiber optic sensor assembly 14 caused by the patient’s heartbeat. For example, peak esophageal wall displacement due to pulsatility of thoracic aorta can be found inside esophagus between carina and the xiphoid. If the fiber shape sensing indicated a resulting trace showing a left or right turn without encountering the heart beat, then the catheter 12 may likely be in the trachea. If the fiber shape sensing indicated a resulting trace showing a left or right turn after encountering a heartbeat, then the catheter 12 may likely be in the stomach. In addition, resulting location of the heartbeat can be used in combination with location of nasopharynx bend to scale the size of the patient, i.e., reproducing the patient’s anatomy. [0069] In some aspects, an anatomical reference can be detected based on signals indicative of transient pressure and/or strain sensed by the fiber optic sensor assembly 14 caused by peristalsis in the patient’s body. In the human body, all parts of the gastrointestinal system (from esophagus to stomach to intestine) have a unique peristalsis profile. Each part of the catheter 12 may be determined to be disposed at an anatomical location based on measured peristalsis by the pressure/strain sensors 50 along the catheter 12 and compared against an expected rate. [0070] In some aspects, an anatomical reference can be detected based on signals indicative of a pressure profile sensed by the fiber optic sensor assembly 14 due to pressure exerted on the catheter 12 by the patient’s anatomy. Each anatomical structure within the patient’s body may have a unique expected pressure profile that can be sensed by the pressure sensor(s) 72. For example, the esophagus is generally a tight orifice, whereas the trachea (respiratory system) is a wide orifice with minimal contact against the catheter 12. However, if a patient is intubated with an endotracheal tube, the endotracheal tube may also have a unique pressure profile coming from the endotracheal tube cuff. Additionally, sphincters such as the esophageal or post-pyloric sphincters which may have unique pressure profile as compared to the esophagus. Pressure measurement can be one dimensional, e.g., with a single point/sensor per cross- section of the tube 16, circumferential, e.g., multiple pressure sensor points per cross-section of the tube 16, and/or a combination of the one dimensional and circumferential. One dimensional measurement may provide pressure profile along the longitudinal length of the catheter 12. Circumferential measurement may provide information about pressures from different sides of the catheter tube 16. [0071] In some aspects, an anatomical reference can be detected based on signals indicative of transient and/or cyclical strain sensed by the fiber optic sensor assembly 14 caused by respiration in the patient’s body. For example, when a catheter 12 enters the chest cavity level (past jugular notch) of a patient, the strain sensor(s) 74 of the fiber optic sensor assembly 14 may experience cyclical deformations due to movement of chest cavity. In contrast, a catheter section in the neck and head may remain stationary or experience non-cyclical transient movement. [0072] In some aspects, an anatomical reference can be detected based on signals indicative of transient pressure and/or strain sensed by the fiber optic sensor assembly 14 caused by other movements of the patient’s body. For instance, coughing, swallowing, gag reflex of a patient may each cause a unique transient force or strain on the sensor(s) 50 depending on the placement of the catheter 12 relative to the patient’s anatomy. A patient may be asked to swallow or cough to induce a transient strain on the catheter 12, enabling sensing using the strain sensor(s) 74 to indicate correct or incorrect placement of the catheter 12. [0073] In some aspects, an anatomical reference can be detected based on signals indicative of transient pressure and/or strain and/or vibration sensed by the fiber optic sensor assembly 14 caused by introduction of air flow through the lumen 28 of the tube 16. For example, one or more air puffs may be introduced through the tube 16. Sound generated by air blown through the tube 16, e.g., the air puffs, may be sensed by the pressure and/or strain and/or vibration sensors. In particular, when the distal end 20 of the tube 16 is disposed in a liquid medium, sound generated by air blown through the tube 16 may be detected. [0074] As briefly described above, the temperature sensor(s) may further be implemented to detect an anatomical reference of the patient, a location of the catheter 12 in the patient’s body, and/or physiological conditions of the patient. For instance, an anatomical reference may be detected based on transient temperature fluctuations from breathing. For example, any parts of the catheter 12 that are in the nasal cavity, nasopharynx, oropharynx, or trachea will see cyclical temperature oscillations. When catheter 12 enters esophagus or remainder of the gastrointestinal system, temperature should reach a stable point. In other aspects, the anatomical reference may be transient temperature fluctuations from swallowing fluids. For example, a patient can be asked to swallow fluids at a known temperature to assist with the placement of a catheter 12 in the gastrointestinal system. This fluid will induce a transient change in temperature along the length of the catheter 12 that follows the gastrointestinal path. If any part of the tube 16 is not in the gastrointestinal path, e.g., in the lungs, then that portion of the tube 16 would not sense the temperature change of the swallowed fluid. Moreover, in some aspects, temperature can be used to sense and detect aspiration of gastric fluids into the respiratory system. The gastric fluid may have the same temperature as the body temperature. Aspiration may be detected at a location of the patient’s oropharynx or hypopharynx cavity by observing cessation of the cyclical temperature variation expected in the respiratory cavity. [0075] The present inventors have found that the multi-modal sensing capability and integration of signals received from the multi-modal sensors yields superior anatomical reference and catheter location detection as compared to an analysis of sensor data from a single sensing modality. [0076] For instance, as described above, catheter partition can be detected by monitoring and combining information from pressure, strain, temperature sensors and shape sensors of the catheter 12. For example, a portion of the catheter 12 can be identified as inside the patient’s body if that portion of the catheter 12 is: at body temperature (as compared to ambient/room temperature; and indicating pressure and/or radial strain at a partition delineating point from user fingers as the user advances the catheter 12 towards the patient’s body; and/or a partition delineating point indicates increased longitudinal strain feedback as the delineating point is pressed against the nasal cavity tissue, or increased baseline pressure caused by nasal cavity tissue is detected at a partition delineating point along the catheter. [0077] Placement of the catheter 12 in a nasopharynx of a patient may be detected by monitoring and combining information from pressure, strain, and temperature sensors and the detected shape of the catheter 12 that are located inside the body. For example, nasopharynx placement can be detected if: the distal portion 20 of the catheter 12 is at body temperature; the distal portion 20 of the catheter 12 indicates the unique shape of nasopharynx bend. Additionally, detection of placement of the catheter 12 in a nasopharynx of a patient may be further informed by NEX measurement, e.g., utilizing the placement of one or more sensors 50 relative to the NEX length measurement, for instance using an analysis of a combination of the insertion length of the catheter and the NEX measurement. Additionally, detection of placement of the catheter 12 in a nasopharynx of a patient may be further informed by one or more external reference landmarks established to either inform of patient size and/or of location of relevant anatomical features (xiphoid, jugular notch, etc) relative to the sensors 50 inside the patient. [0078] Placement of the catheter 12 in the trachea of a patient may be detected by monitoring and combining information from pressure and/or strain and/or temperature sensors and/or sensing the shape of the catheter 12. For example, trachea placement can be detected by combining: detection of cyclical temperature, e.g., caused by breathing; cyclical pressure and/or strain or shape deformation of catheter 12, e.g., caused by breathing; transient pressure and/or strain or shape deformation of catheter 12, e.g., caused by coughing, closing of the epiglottis (gag reflex); detection of minimal to zero baseline pressure, as the trachea is much wider than catheter 12; detection of vibration, e.g., from contact of the catheter 12 against larynx/vocal cords/tracheal rings; circumferential pressure sensing indicating only one side of the catheter 12 experiencing tissue contact or pressure (because the trachea is much wider than catheter 12); elevated local pressure detected at a point of the catheter 12, e.g., in contact with an endotracheal tube cuff, in addition to lack of cyclical temperature variation. Additionally, detection of placement of the catheter 12 in a trachea of a patient may be further informed by NEX measurement, e.g., utilizing the placement of one or more sensors 50 relative to the NEX length measurement, for instance using an analysis of a combination of the insertion length of the catheter and the NEX measurement. Additionally, detection of placement of the catheter 12 in a trachea of a patient may be further informed by one or more external reference landmarks established to either inform of patient size and/or of location of relevant anatomical features (xiphoid, jugular notch, etc) relative to the sensors 50 inside the patient. [0079] Placement of the catheter 12 in one of the lungs of a patient may be detected by monitoring and combining information from pressure and/or strain and/or temperature sensors and/or sensing the shape of the catheter 12. For example, lung placement can be detected by combining: shape of the pathway of advancement of the catheter 12 advancing and deviating to the left or right; and lack of detection of cyclical pressure and/or strain from the thoracic aorta; cyclical temperature variation due to breathing; detection of transient pressure and/or strain, e.g., caused by coughing; detection of vibration of the catheter 12 caused by contact against cartilage/bronchial rings. Additionally, detection of placement of the catheter 12 in a lung of a patient may be further informed by NEX measurement, e.g., utilizing the placement of one or more sensors 50 relative to the NEX length measurement. Additionally, detection of placement of the catheter 12 in a lung of a patient may be further informed by one or more external reference landmarks established to either inform of patient size and/or of location of relevant anatomical features (xiphoid, jugular notch, etc) relative to the sensors 50 inside the patient. [0080] Placement of the catheter 12 in the esophagus of a patient may be detected by monitoring and combining information from pressure and/or strain and/or temperature sensors and/or sensing the shape of the catheter 12. For instance, esophageal placement may be detected by combining: detection of a stable body temperature instead of cyclical temperature variations; detection of elevated baseline pressure against the catheter 12 caused by contact in the narrow esophageal pathway; circumferential pressure sensors sensing contact pressure on all sides of the catheter 12 caused by contact in the narrow esophageal pathway; detection of transient pressure and/or strain, e.g., caused by peristalsis or swallowing; detection of elevated local pressure and/or strain, e.g., caused by transient events from the upper esophageal sphincter. Additionally, detection of placement of the catheter 12 in the esophagus of a patient may be further informed by NEX measurement, e.g., utilizing the placement of one or more sensors 50 relative to the NEX length measurement, for instance using an analysis of a combination of the insertion length of the catheter and the NEX measurement. Additionally, detection of placement of the catheter 12 in the esophagus of a patient may be further informed by one or more external reference landmarks established to either inform of patient size and/or of location of relevant anatomical features (xiphoid, jugular notch, etc) relative to the sensors 50 inside the patient. [0081] Placement of the catheter 12 in the stomach of a patient may be detected by monitoring and combining information from pressure and/or strain and/or temperature sensors and/or sensing the shape of the catheter 12. For instance, stomach placement may be detected by combining: a detection of a stable body temperature instead of cyclical temperature variations; detection of elevated local pressure and/or strain caused by contact between the catheter 12 and the lower esophageal sphincter; detection of a change, e.g., reduction, in baseline pressure caused by distal end 20 of the catheter moving from narrow lumen of esophagus to wide lumen of stomach; detection of cyclical pressure and/or strain, e.g., caused by stomach motility; detection of a transition from air to gastric fluid, e.g., detected by a change in pressure and/or temperature profile. Additionally, detection of placement of the catheter 12 in the stomach of a patient may be further informed by NEX measurement, e.g., utilizing the placement of one or more sensors 50 relative to the NEX length measurement, for instance using an analysis of a combination of the insertion length of the catheter and the NEX measurement. Additionally, detection of placement of the catheter 12 in the stomach of a patient may be further informed by one or more external reference landmarks established to either inform of patient size and/or of location of relevant anatomical features (xiphoid, jugular notch, etc) relative to the sensors 50 inside the patient. [0082] Moreover, stomach placement of the catheter 12 may be confirmed by combining the above described sensing characteristics with additional confirmatory actions and/or measurements. For instance, external palpation or tapping of the stomach region of a patient’s body may be detected. Additionally or alternatively, a puff of air may be delivered through the tube 16 to cause an audible or vibration event in the stomach that could be detected by pressure and/or strain sensors. [0083] In some aspects, the shape and/or movement of the catheter 12 may be detected. For instance, tube coiling in the stomach may be identified by combination of pressure, strain, or shape data. For example, tube coiling may be identified by: detection of shape of the tube 16 in a coiled shape; inferential detection of coiling if a pressure and/or strain pattern is repeated over a long length of the catheter 12; inferential detection of coiling if strain information indicates a curvature and direction indicative of a pattern of a coiled catheter. A pattern indicative of a coiled catheter may be: repeated pressure/strain pattern such as a static baseline pressure pattern that represents continuous bend of the catheter, and/or a cyclical pressure wave (e.g., representative of stomach motility) that repeats across a long length of the catheter. [0084] Placement of the catheter 12 in the small intestine, e.g., post-pyloric region, of a patient may be detected by monitoring and combining information from pressure and/or strain and/or temperature sensors and/or sensing the shape of the catheter 12. For instance, small intestinal placement may be detected by combining: a detection of a stable body temperature instead of cyclical temperature variations; detection of local pressure and/or strain caused by contact with the pylorus (pyloric sphincter); detection of increased baseline pressure relative to the stomach (due to smaller orifice of small intestine); detection of a unique cyclical pressure/strain profile caused by peristalsis). Additionally, detection of placement of the catheter 12 in the small intestine of a patient may be further informed by NEX measurement, e.g., utilizing the placement of one or more sensors 50 relative to the NEX length measurement. Additionally, detection of placement of the catheter 12 in the small intestine of a patient may be further informed by one or more external reference landmarks established to either inform of patient size and/or of location of relevant anatomical features (xiphoid, jugular notch, etc) relative to the sensors 50 inside the patient. [0085] Moreover, displacement of the catheter 12 may be detected using the principles described above. For example, retraction of the catheter 12 may be detected by identifying regression of the sensed characteristics to a previous state in time and/or a reduction in the measured value of the insertion length of the catheter 12. Exemplary Methods [0086] FIG.8, FIG.9, FIG.10, and FIG.11 are flow charts depicting methods 800, 900, 1000, 1100 of using the intelligent catheter system and/or fiber optic sensor assembly in accordance with certain embodiments of the present disclosure. The exemplary methods facilitate detection of a location of a catheter in a patient’s body relative to human anatomy and monitoring of physiological conditions in a vicinity of the catheter, physiological parameters of the patient’s body, and/or externally induced physiological conditions based on signals received (e.g., obtained, retrieved) from the intelligent catheter system and/or fiber optic sensor assembly. The exemplary methods further facilitate nutritional management and monitoring, including derivation of patient’s metabolic rate and nutrient absorption. This disclosure contemplates that at least a portion of each method 800, 900, 1000, 1100 can be at least partially performed by a processor, console 102, and/or display 110 as described in more detail herein. [0087] With reference to FIG.8, the example method 800 begins at step 802 by advancing a catheter/tube into a patient’s nostril. At step 804, the method 800 includes identifying and displaying a portion of the catheter that is inside the patient’s body (e.g., via the console 102 and/or display 110). At step 806, the method 800 includes detection of a stable body temperature and/or determining whether a catheter section is delineated by point pressure from the fingers. Step 806 can include sensing two or more characteristics (e.g., a shape of the catheter, pressure, strain, vibration, and temperature) along at least a subsection of the catheter. For example, sensing a first set of characteristics along a first subsection of the catheter via a first set of sensors, sensing a second set of characteristics along a second subsection of the catheter via a second set of sensors, and determining one or more physiological parameters and/or physiological conditions based on evaluation of the first set of characteristics and the second set of characteristics (e.g., by comparing, correlating, or assessing relative values of the obtained signals). At step 808, the method 800 includes monitoring for nasopharynx placement. At step 810, the method 800 includes determining a position of the catheter inside the body, for example by detecting a nasopharynx bend or based on NEX measurement agreement (sensor location). If the catheter is determined to be in an incorrect (e.g., non-target) location, the method 800 can terminate or return to step 802 where the tube is retracted and then advanced again. If the catheter is determined to be in the correct position, the method 800 proceeds to step 812 and nasopharynx placement proceeds by advancing the tube into the patient’s esophagus, as also shown in FIG.9, step 902. [0088] Referring now to FIG.9, subsequent to advancing the tube into the patient’s esophagus at step 902, the method 900 proceeds to step 904 and includes monitoring for trachea vs esophagus placement of the tube. At step 906, the method 900 includes identifying one or more characteristics along at least a subsection of the catheter, for example, based at least in part on NEX measurement agreement or external reference agreement (shape). In some cases, at step 906, the method includes identifying one or more characteristics along at least a subsection of the catheter that indicate that the tube is positioned in the trachea including at least one of cyclical temperature (breathing), cyclical pressure of shape deformation (indicative of breathing), transient deformation (coughing or positioning within the epiglottis), and minimal baseline pressure (indicative of a wide orifice). In response to determining that the tube is positioned in the trachea, the method 900 can include prompting the user to retract the tube at step 908. At step 910, the method 900 includes monitoring for retraction or lung placement. At step 912, the method 900 includes identifying one or more characteristics indicating tube retraction. As illustrated, such characteristics can include a detected shape regression back to nasopharynx state, cyclical deformation stops (breathing), transient deformation stops (coughing or positioning within the epiglottis), and minimal baseline pressure. In response to detecting retraction of the tube, the method 900 can terminate or return to step 902. [0089] In some cases, at step 918, the method 900 includes identifying one or more characteristics along at least a subsection of the catheter that indicate that the tube is properly positioned in the esophagus including at least one of a stable body temperature, cyclical deformation (breathing), transient pressure (peristalsis from swallowing), elevated local pressure with transient events (elevated local pressure with transient events (UES)), and increasing cyclical pressure (heart beat). In response to determining that the tube is positioned in the esophagus, at step 920, the method 900 includes advancing the tube in the esophagus. At step 922, the method 900 can optionally include performing a secondary confirmation with the patient (e.g., in an instance in which the patient is awake). At step 924, the method 900 can include asking the patient to swallow water. Then, at step 926, the method 900 includes detecting a transient temperature drop or transient pressure wave due to swallow peristalsis from the water. At step 928, the method 900 includes confirming esophagus placement and advancing to the method 1000 shown in FIG.10, for example, by outputting an indication or audio or visual alert via the console 102/display 110. Alternatively, as illustrated in FIG.9, the method 900 can proceed from step 920 to 928 without the secondary confirmation. [0090] Referring now to FIG.10, subsequent to confirming esophagus placement at step 928 in FIG.9, also shown as step 1002 in FIG.10, the method 1000 proceeds to step 1004 and includes monitoring for stomach placement. At step 1006, the method 1000 includes determining one or more characteristics indicating stomach placement based on, for example, NEX measurement agreement or external reference agreement. The one or more characteristics can include at least one of a stable body temperature, elevated point pressure (lower esophageal sphincter (LES)), transition between different baseline pressure jogs (esophagus- narrow to stomach-wide lumen), cyclical pressure (heart beat), and unique pathway shape. At step 1008, the method 1000 includes confirming the stomach placement. Then, the method 1000 can end (i.e., proceed to step 1016) or can optionally include determining a secondary confirmation at step 1010. At step 1012, the secondary confirmation can include applying external pressure, tapping on the patient’s stomach, and/or using auscultation and then, at step 1014, determining one or more additional characteristics to confirm the stomach placement. The one or more additional characteristics can include a transient pressure increase, periodic pressure variation, and/or vibration from air bubbles. Then, the method 1000 proceeds to step 1016 where the stomach placement is confirmed, for example, by outputting an indication or audio or visual alert via the console 102/display 110. [0091] Referring now to FIG.11, subsequent to confirming the stomach placement at step 1016 of FIG.10 (also shown as step 1102 in FIG.11), the method 1100 proceeds to step 1104 and includes monitoring for coiling or post-pyloric (PP) placement based on, for example, NEX measurement agreement or external reference agreement. At step 1106, the method 1100 includes identifying one or more characteristics along at least a subsection of the catheter that indicate that the tube is coiled. The one or more characteristics can include at least one of a stable body temperature, coiling (shape), repetitive baseline pressure or strain over long jog, and repetitive cyclical pressure or strain over long job (mobility). At step 1108, in response to determining that the tube is coiled based on the determined one or more characteristics, the method 1100 proceeds to step 1110 and includes monitoring for retraction or further coiling. At step 1112, the method 1100 includes detecting one or more additional characteristics including, for example, shape regression back to a reduced pathway or stomach state, LES/esophageal pressure profile moving closer to the tube tip. [0092] At step 1114, the method 1100 includes identifying one or more characteristics along at least a subsection of the catheter that indicate PP placement based on, for example, NEX measurement agreement or external reference agreement. The one or more characteristics can include at least one of stable body temperature, local pressure from the pyloric sphincter, higher baseline pressure (narrow orifice), unique cyclical pressure wave (motility), and a unique pathway shape. At step 1116, in response to determining, based on the one or more characteristics, that the catheter is in the PP, the method 1100 can optionally proceed with secondary confirmation at step 1118. At step 1120, the secondary confirmation can include applying external pressure and/or tapping on the patient’s stomach. Additionally or alternatively, a puff of air may be delivered through the tube to cause an audible or vibration event in the stomach that could be detected by pressure and/or strain sensors. At step 1122, subsequent to applying external pressure and/or tapping on the patient’s stomach, the method 1100 includes detecting one or more additional characteristics including, for example, transient pressure increase and periodic pressure variation. Then, the method 1100 proceeds to step 1124 and includes confirming the stomach placement, for example, by outputting an indication or audio or visual alert via the console 102/display 110. [0093] In some aspects of the disclosure, the fiber optic sensor assembly 14 as part of the electronic catheter unit 100 may enable detection and/or diagnosis of a state of a patient’s digestive health. For instance, detection of transient or cyclical strain, pressure and/or shape data may be used to measure spatiotemporal motility (peristalsis) in various parts of the gastrointestinal system. For example, transient or cyclical strain and/or pressure data may enable calculation of derived motility rates of the stomach, small intestine, etc, to quantify stomach emptying rates and some gastrointestinal disorders. In combination with detection of stomach contents and the derived motility rates, energy (i.e., calorie) absorption in the gastrointestinal system may be quantified. In addition, combining heart rate, respiration rate and body temperature one can derive and monitor metabolic process and help balance energy expenditure vs absorption. Similarly, pressure and/or strain signals may be analyzed to distinguish between cyclical pressure waves and transient events measured in the gastrointestinal tract. Prevalence and type of transient waves in GI tract can indicate health of GI. For example, most pressure waves in the stomach and small bowel are cyclical. Excess of transient events (change in cyclical rate, or non-periodic pressure waves) could indicate abnormal gastrointestinal health. Moreover, measurement of the baseline pressure by the catheter 12 may be used to measure stomach distension, e.g., during food ingestion compared to lack thereof. In some aspects, transient pressure or strain data may be used to identify and quantify carbon dioxide (CO2) production in the stomach, i.e., by detecting belching or burping of excess CO2 by the pressure and/or strain sensors in a portion of the catheter 12 disposed in the patient’s esophagus. Moreover, the derived information about motility, stomach emptying, stomach fullness and excessive presence of CO2 may then be used to inform a desired delivery rate of enteral nutritional formula, i.e., for meal planning. Further, the spatially distributed pressure and/or strain sensors and/or shape sensors may monitor tube occlusion during enteral feeding and provide a signal informing a user of any critical interruption. [0094] This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they include structural elements that do not differ from the literal language of the claims or if they include equivalent structural elements with insubstantial differences from the literal language of the claims. Exemplary Aspects [0095] In view of the described device and processes, herein are described certain more particularly described aspects of the disclosures. These particularly recited aspects should not, however, be interpreted to have any limiting effect on any different claims containing different or more general teachings described herein, or that the “particular” aspects are somehow limited in some way other than the inherent meanings of the language and formulas literally used therein. [0096] Further exemplary aspects of the disclosure are provided by one or more of the following examples: [0097] Example 1. A tubing assembly comprising: a catheter having a proximal end and a distal end and extending in a longitudinal direction, the catheter having a wall extending from the proximal end to the distal end, the catheter wall defining a lumen therein, and wherein the catheter is configured for placement within a digestive tract of a patient; and a fiber optic sensor assembly, the fiber optic sensor assembly being configured to sense two or more characteristics along at least a subsection of the catheter, the two or more characteristics selected from the group consisting of: a shape of the catheter, pressure, strain, vibration, and temperature. [0098] Example 2. The tubing assembly of example 1, wherein the fiber optic sensor assembly includes at least one fiber optic sensor disposed in the catheter wall. [0099] Example 3. The tubing assembly of example 1, wherein the fiber optic sensor assembly includes at least one fiber optic sensor extending within the lumen of the catheter. [0100] Example 4. The tubing assembly of example 1, wherein the fiber optic sensor assembly comprises a plurality of spatially distributed sensors. [0101] Example 5. The tubing assembly of example 4, wherein the plurality of spatially distributed sensors are spatially distributed in the longitudinal direction of the catheter. [0102] Example 6. The tubing assembly of example 4, wherein the plurality of spatially distributed sensors are spatially distributed about the lumen of the catheter. [0103] Example 7. The tubing assembly of example 1, wherein the fiber optic sensor assembly includes at least one single core fiber optic cable. [0104] Example 8. The tubing assembly of example 1, wherein the fiber optic sensor assembly includes a multi-core fiber optic cable. [0105] Example 9. The tubing assembly of example 8, including a removable stylet insertable in the lumen of the catheter, wherein the multi-core fiber optic cable is integrated in the stylet. [0106] Example 10. A catheter system comprising: a catheter having a proximal end and a distal end and extending in a longitudinal direction, the catheter having a wall extending from the proximal end to the distal end, the catheter wall defining a lumen therein, and wherein the catheter is configured for placement within a digestive tract of a patient; a fiber optic sensor assembly, the fiber optic sensor assembly being configured to sense two or more characteristics along at least a subsection of the catheter, the two or more characteristics selected from the group consisting of: a shape of the catheter, pressure, strain, vibration, and temperature; and a processor; wherein the fiber optic sensor assembly senses the two or more characteristics and transmits signals related to the two or more characteristics to the processor; wherein the processor is configured to detect a location of the catheter in a patient's body relative to human anatomy, physiological conditions in a vicinity of the catheter, physiological parameters of the patient's body, and/or externally induced physiological conditions based on the signals received from the fiber optic assembly. [0107] Example 11. The catheter system of example 10, wherein human anatomy includes three-dimensional (3D) curves that represent either airway or gastrointestinal (GI) passage. [0108] Example 12. The catheter system of example 10, wherein the physiological conditions include characteristics of esophago-gastro-jejunal motility, esophago-gastro-jejunal contents, reflux, swallow, gag, and/or cough movements to aid in nutritional management and/or diagnoses and monitoring of gastrointestinal health. [0109] Example 13. The catheter system of example 10, wherein the physiological parameters include body temperature, heart rate, respiration rate, and peristalsis of gastrointestinal subsystems. [0110] Example 14. The catheter system of example 10, wherein the physiological parameters are configured to be used by the processor to derive the patient's metabolic rate and nutrient absorption. [0111] Example 15. The catheter system of example 10, wherein the externally induced physiological conditions include swallowing water, stomach palpation, inducing puffs of air. [0112] Example 16. The catheter system of example 10, wherein the fiber optic sensor assembly and the processor are configured to sense at least one of the two or more characteristics using Fiber Bragg Grating. [0113] Example 17. The catheter system of example 10, wherein the fiber optic sensor assembly and the processor are configured to sense at least one of the two or more characteristics using Raman scattering, Rayleigh scattering, and/or Brillouin scattering. [0114] Example 18. The catheter system of example 10, wherein the fiber optic sensor assembly comprises a plurality of spatially distributed sensors, wherein the plurality of spatially distributed sensors are either spatially or time multiplexed. [0115] Example 19. A method for using a catheter system, the method comprising: placing the catheter system within a digestive tract of a patient, the catheter system having a proximal end and a distal end and extending in a longitudinal direction, the catheter having a wall extending from the proximal end to the distal end, the catheter wall defining a lumen therein; sensing, using a fiber optic sensor assembly, two or more characteristics along at least a subsection of the catheter, the two or more characteristics selected from the group consisting of: a shape of the catheter, pressure, strain, vibration, and temperature; transmitting signals related to the two or more characteristics to a processor; and detecting, by the processor, a location of the catheter in a patient's body relative to human anatomy, physiological conditions in a vicinity of the catheter, physiological parameters of the patient's body, and/or externally induced physiological conditions based on the signals received from the fiber optic assembly determining, by the processor and based, at least in part on the physiological parameters, the patient's metabolic rate and/or nutrient absorption. [0116] Example 20. The method of example 19, wherein sensing the two or more characteristics along at least a subsection of the catheter comprises using Fiber Bragg Grating, Raman scattering, Rayleigh scattering, and/or Brillouin scattering. [0117] The tubing assembly or catheter system according to any example herein, particularly example 1, An exemplary technical effect of the methods, systems, and apparatus described herein includes at least one of, but are not limited to: a) better accommodating for different types of nutrition, b) better accounting for occlusions that may occur within an enteral feeding system as it relates to varying types of nutrition, and c) improving ease of different types of nutrition with an enteral feeding system with or without additional input from a patient or provider. [0118] This written description uses examples to disclose the disclosure, including the best mode, and also to enable any person skilled in the art to practice the disclosure, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the disclosure is defined by the claims and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they include structural elements that do not differ from the literal language of the claims or if they include equivalent structural elements with insubstantial differences from the literal language of the claims.

Claims

CLAIMS What is claimed is: 1. A tubing assembly comprising: a catheter having a proximal end and a distal end and extending in a longitudinal direction, the catheter having a wall extending from the proximal end to the distal end, the catheter wall defining a lumen therein, and wherein the catheter is configured for placement within a digestive tract of a patient; and a fiber optic sensor assembly, the fiber optic sensor assembly being configured to sense two or more characteristics along at least a subsection of the catheter, the two or more characteristics selected from the group consisting of: a shape of the catheter, pressure, strain, vibration, and temperature.

2. The tubing assembly of claim 1, wherein the fiber optic sensor assembly includes at least one fiber optic sensor disposed in the catheter wall.

3. The tubing assembly of claim 1, wherein the fiber optic sensor assembly includes at least one fiber optic sensor extending within the lumen of the catheter.

4. The tubing assembly of claim 1, wherein the fiber optic sensor assembly comprises a plurality of spatially distributed sensors.

5. The tubing assembly of claim 4, wherein the plurality of spatially distributed sensors are spatially distributed in the longitudinal direction of the catheter.

6. The tubing assembly of claim 4, wherein the plurality of spatially distributed sensors are spatially distributed about the lumen of the catheter.

7. The tubing assembly of claim 1, wherein the fiber optic sensor assembly includes at least one single core fiber optic cable.

8. The tubing assembly of claim 1, wherein the fiber optic sensor assembly includes a multi-core fiber optic cable.

9. The tubing assembly of claim 8, including a removable stylet insertable in the lumen of the catheter, wherein the multi-core fiber optic cable is integrated in the stylet.

10. A catheter system comprising: a catheter having a proximal end and a distal end and extending in a longitudinal direction, the catheter having a wall extending from the proximal end to the distal end, the catheter wall defining a lumen therein, and wherein the catheter is configured for placement within a digestive tract of a patient; a fiber optic sensor assembly, the fiber optic sensor assembly being configured to sense two or more characteristics along at least a subsection of the catheter, the two or more characteristics selected from the group consisting of: a shape of the catheter, pressure, strain, vibration, and temperature; and a processor; wherein the fiber optic sensor assembly senses the two or more characteristics and transmits signals related to the two or more characteristics to the processor; wherein the processor is configured to detect a location of the catheter in a patient’s body relative to human anatomy, physiological conditions in a vicinity of the catheter, physiological parameters of the patient’s body, and/or externally induced physiological conditions based on the signals received from the fiber optic assembly.

11. The catheter system of claim 10, wherein human anatomy includes three-dimensional (3D) curves that represent either airway or gastrointestinal (GI) passage.

12. The catheter system of claim 10, wherein the physiological conditions include characteristics of esophago-gastro-jejunal motility, esophago-gastro-jejunal contents, reflux, swallow, gag, and/or cough movements to aid in nutritional management and/or diagnoses and monitoring of gastrointestinal health.

13. The catheter system of claim 10, wherein the physiological parameters include body temperature, heart rate, respiration rate, and peristalsis of gastrointestinal subsystems.

14. The catheter system of claim 10, wherein the physiological parameters are configured to be used by the processor to derive the patient’s metabolic rate and nutrient absorption.

15. The catheter system of claim 10, wherein the externally induced physiological conditions include swallowing water, stomach palpation, inducing puffs of air.

16. The catheter system of claim 10, wherein the fiber optic sensor assembly and the processor are configured to sense at least one of the two or more characteristics using Fiber Bragg Grating.

17. The catheter system of claim 10, wherein the fiber optic sensor assembly and the processor are configured to sense at least one of the two or more characteristics using Raman scattering, Rayleigh scattering, and/or Brillouin scattering.

18. The catheter system of claim 10, wherein the fiber optic sensor assembly comprises a plurality of spatially distributed sensors, wherein the plurality of spatially distributed sensors are either spatially or time multiplexed.

19. A method for using a catheter system, the method comprising: placing the catheter system within a digestive tract of a patient, the catheter system having a proximal end and a distal end and extending in a longitudinal direction, the catheter having a wall extending from the proximal end to the distal end, the catheter wall defining a lumen therein; sensing, using a fiber optic sensor assembly, two or more characteristics along at least a subsection of the catheter, the two or more characteristics selected from the group consisting of: a shape of the catheter, pressure, strain, vibration, and temperature; transmitting signals related to the two or more characteristics to a processor; and detecting, by the processor, a location of the catheter in a patient’s body relative to human anatomy, physiological conditions in a vicinity of the catheter, physiological parameters of the patient’s body, and/or externally induced physiological conditions based on the signals received from the fiber optic assembly determining, by the processor and based, at least in part on the physiological parameters, the patient’s metabolic rate and/or nutrient absorption.

20. The method of claim 19, wherein sensing the two or more characteristics along at least a subsection of the catheter comprises using Fiber Bragg Grating,^Raman scattering, Rayleigh scattering, and/or Brillouin scattering.