Patent Publication Number: US-2021162153-A1

Title: Systems And Methods For Monitoring Tracheotomy Patients

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims priority to co-pending U.S. Provisional Application Ser. No. 62/595,177, filed Dec. 6, 2017, which is hereby incorporated by reference herein in its entirety. 
    
    
     BACKGROUND 
     Tracheotomy procedures, in which a passageway is formed through an incision in the neck to create an airway, are common. When a tracheotomy is performed, a tracheotomy tube is typically passed through the passageway to maintain its patency and provide a secure airway. 
     A common concern with tracheotomies and tracheotomy tubes is that the tube will become dislodged. Such dislodgement can range in severity from the tube shifting out of position and creating an air leak to the tube becoming completely removed from the passageway. Another concern is that the tracheotomy tube will become occluded, for example, with mucus generated by the patient. These situations pose a health risk to the patient and, potentially, a risk of death. 
     Given that tracheotomy tube dislodgement or occlusion may go unrecognized, it would be beneficial to have a means for monitoring the patient to ensure that the tracheotomy tube is in position and clear of obstruction. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present disclosure may be better understood with reference to the following figures. Matching reference numerals designate corresponding parts throughout the figures, which are not necessarily drawn to scale. 
         FIG. 1  is a first perspective view of an embodiment of a tracheotomy tube monitoring device. 
         FIG. 2  is a second perspective view of the tracheotomy tube monitoring device of  FIG. 1 . 
         FIG. 3  is a first cross-sectional perspective view of the tracheotomy tube monitoring device of  FIG. 1 . 
         FIG. 4  is a second cross-sectional perspective view of the tracheotomy tube monitoring device of  FIG. 1 . 
         FIG. 5  is a perspective view of an embodiment of internal electrical components of the tracheotomy tube monitoring device of  FIG. 1 . 
         FIG. 6  is a side view of the tracheotomy tube monitoring device of  FIG. 1  attached to a tracheotomy tube. 
         FIG. 7  is a cross-sectional perspective view of a further embodiment of a tracheotomy tube monitoring device. 
         FIG. 8  is a schematic view of a system for monitoring tracheotomy patients that includes a tracheotomy tube monitoring device and other devices configured to receive signals transmitted by the monitoring device. 
     
    
    
     DETAILED DESCRIPTION 
     As can be appreciated from the discussion above, it would be desirable to have a system or method for monitoring a tracheotomy patient that can detect tracheotomy tube dislodgement or occlusion. Disclosed herein are examples of such systems and methods. In some embodiments, a monitoring system includes a tracheotomy tube monitoring device capable of monitoring patient respiration that attaches to the tracheotomy tube. In some embodiments, patient respiration is monitored using a conductive membrane of the device that is in contact with a sensing element of the device when the patient exhales and is pulled out of contact with the sensing element when the patient inhales. From this contact and non-contact, patient respiration can be monitored and analyzed. In other embodiments, patient is monitored using a pressure sensor in lieu of a conductive membrane. Such an embodiment is useful in cases in which the patient cannot tolerate the membrane, which functions in similar manner to a speaking valve. When no breathing or impaired breathing is detected, the device can generate an alert to warn appropriate persons. In some embodiments, the device emits an audible alarm and also wirelessly transmits an alert signal to an appropriate computing device, such as a smart phone and/or a computer. 
     In the following disclosure, various specific embodiments are described. It is to be understood that those embodiments are example implementations of the disclosed inventions and that alternative embodiments are possible. Such alternative embodiments include hybrid embodiments that include features of different disclosed embodiments. All such embodiments are intended to fall within the scope of this disclosure. 
       FIGS. 1 and 2  illustrate an embodiment of a tracheotomy tube monitoring device  10  that can comprise part of a system for monitoring tracheotomy patients. As shown in these figures, the illustrated monitoring device  10  includes a body portion  12  that contains internal electrical components of the device and a tube mounting portion  14  that is configured to mount the device to a tracheotomy tube. In this embodiment, the body portion  12  is formed as a generally rectangular housing  16 . Provided on the housing  16  is an indicator  17 , such as a light-emitting diode (LED) indicator light that illuminates when the device is activated. The tube mounting portion  14  is formed as a generally cylindrical airflow tube  18 . As shown in  FIG. 3 , the airflow tube  18  is hollow and includes an inlet opening  20  and an outlet opening  22  through which air can flow. In some embodiments, the outlet opening  22  is sized and configured to receive the distal end of the tracheotomy tube with a press fit. 
     With reference to  FIGS. 1-3 , the tracheotomy tube monitoring device  10  further includes an end cap  24  that is mounted to the inlet end of the airflow tube  18 . The end cap  24  includes a series of passages  26  through which air can flow. The passages  26  are defined by outer ribs  28  that extend radially outward from the center of the end cap  24  to its outer periphery. As is shown in  FIG. 3 , inner ribs  29  can be provided within the airflow tube  18  to provide structural integrity to the tube and to limit insertion of the tracheotomy tube. 
     With further reference to  FIG. 3 , positioned between the end cap  24  and the airflow tube  18  on the inner side of the outer ribs  28  is a flexible membrane  30 , which can, for example, be made of a flexible elastomeric material, such as a polymer elastomer, silicone, or rubber. The center of the membrane  30  is secured to the end cap  24  with a generally conical retainer element  32  that extends from the center of the end cap. The edges of the membrane  30 , however, are not secured to the end cap  24  and, therefore, can deform (i.e., bend inward) to enable air to pass through the end cap  24 , past the membrane, and into the airflow tube  18  during patient inhalation. 
     At least a top side  34  of the membrane  30  is electrically conductive so that contact between the membrane and a sensing element  36  can be detected. This electrical conductivity can, for example, be provided by a thin conductive substrate that is applied to the membrane  30  or a conductive material that is deposited on the surface of the membrane. In some embodiments, the conductive substrate/material is a metal material, such as gold. The sensing element  36  can comprise a small circuit board having electrical contacts that are placed in contact with the top side  34  of the membrane  30  when the patient is not inhaling, thereby closing an electrical circuit. In the illustrated embodiment, the sensing element  36  is contained within a small housing  38  that forms part of the end cap  24 . 
     With reference next to  FIGS. 3-5 , the sensing element  36  is in electrical communication with internal electrical components  40  of the tracheotomy tube monitoring device  10  that are contained within an interior space  42  of the body portion  12 . In the illustrated embodiment, these electrical components  40  include a circuit board  44  and a battery  46 , which may be rechargeable. Mounted to the circuit board  44  is a microcontroller  48  configured to control the overall operation of the device  10 , a wireless transceiver chip  50  configured to wirelessly transmit signals to other devices (e.g., via Bluetooth or WiFi), and a speaker  52  configured to generate an audible alarm, which can be emitted through an opening  54  provided in the body portion  12 . 
     Also mounted to the circuit board  44  is an accelerometer  55  that is configured to sense vibrations transmitted by the tracheotomy tube to the monitoring device  10 . Such vibrations can include those associated with patient breathing as well as those associated with the presence of an obstruction within the tracheotomy tube, such as a mucus plug. In some embodiments, the accelerometer  55  can also sense vibrations associated with other phenomena. For example, the accelerometer  55  may be capable of sensing beating of the patient&#39;s heart so that the monitoring device  10  can monitor patient heart rate. As another example, the accelerometer  55  may be capable of sensing patient movements, such as sitting up, walking, falling, and the like. It is noted that a microphone could be used in lieu of or conjunction with the accelerometer  55  to sense vibrations. 
     With reference back to  FIG. 3 , the monitoring device  10  can further include a connection sensor  56  that is configured to sense a physical parameter, such as pressure, that is indicative of a positive connection to a tracheotomy tube. If the connection sensor  56  does not sense such a connection, an alert can be generated. 
     As noted above, the tracheotomy tube monitoring device  10  is configured to be removably attached to a tracheotomy tube. In particular, as depicted in  FIG. 6 , the distal end of the tracheotomy tube  60  can be inserted into the airflow tube  18  of the monitoring device  10  until a snug (interference) fit is achieved and/or the tracheotomy tube abuts the inner ribs  29 . Once the monitoring device  10  is so attached and then activated (e.g., using a switch or button provided on the device (not shown)), the device can monitor patient respiration with for purpose of detecting tracheotomy tube dislodgement and/or occlusion. The monitoring device  10  does this by detecting the cyclic contact and non-contact between the conductive membrane  30  and the sensing element  36 . 
     When the patient inhales, air is drawn through the tracheotomy tube and creates a vacuum within the airflow tube  18  that causes the membrane  30  to separate from the sensing element  36  along its outer edges and enables air to flow around the membrane, through the airflow tube, and to the patient. When this separation occurs, the electrical connection between the sensing element  36  (which is positioned near the outer edge of the membrane  30 ) and the membrane is lost. When the patient exhales, positive pressure is applied to the membrane  30  within the airflow tube  18  to return the membrane to its original orientation in which it makes positive contact with the sensing element  36 . In addition, the membrane  30  is pressed into contact with the ribs  28  at which point no air flows through the device  10 . Accordingly, the end cap  24  and membrane  30  together function as a one-way valve that enables air to flow through the device  10  only during inhalation. 
     It is noted that the above form of operation also enables the device  10  to function as a speaking valve. In particular, when the patient exhales to speak, the membrane  30  is urged against the outer ribs  28  of the end cap  24  so as to close the passages  26  so that exhaled air will flow through the vocal cords instead of the device  10 . In cases in which this functionality is not desired, holes (not shown) can be provided in the airflow tube  18  to enable exhaled air to escape from the device  10 . Even in such a case, the membrane  30  is urged against the outer ribs  28  as there is still adequate air pressure within the airflow tube  18  to achieve this. Moreover, in some embodiments, the natural position for the membrane  30  is one in which it is in positive contact with the outer ribs  28  as the membrane naturally seats against the ribs. In that case, positive pressure is not necessary to create contact between the membrane  30  and the sensing element  36 . 
     The microcontroller  48  monitors the signals received from the sensing element  36  (i.e., an open circuit condition during inhalation and a closed-circuit condition during exhalation) and uses these signals to evaluate the respiration of the patient. More particularly, the microcontroller  48  uses software or firmware (i.e., computer-readable, executable instructions, which may embody one or more algorithms) to analyze the rhythms of the patient&#39;s breathing. As long as the monitored signals are indicative of normal patient breathing, it is presumed that the tracheotomy tube is in proper position and is not occluded. If the signals are not indicative of normal patient breathing, however, an alert is generated as this condition may be indicative of improper tracheotomy tube placement and/or occlusion. As mentioned above, the alert can be an alarm that is emitted by the speaker  52  and/or an alert signal that is wirelessly transmitted to another device. In addition, the software/firmware can receive signals from the accelerometer  55  and the connection sensor  56  and issue alerts as necessary based upon the signals that are received (e.g., clogging of the tracheotomy tube, improper connection with the tracheotomy tube, etc.). 
       FIG. 7  illustrates a further embodiment of a tracheotomy tube monitoring device  70 . The monitoring device  70  is similar in many ways to the monitoring device  10  shown in  FIGS. 1-5 . In some embodiments, the monitoring device  70  comprises nearly all of the same components of the monitoring device  10 . Accordingly, the monitoring device  70  comprises a body portion  12  and a tube mounting portion  14  that includes an airflow tube  18 . The monitoring device  70  further includes an end cap  24  having series of passages  26  through which air can flow. In this embodiment, however, the monitoring device  70  comprises no membrane configured to close when the patient exhales. Instead of a membrane and a sensing element that detects contact with the membrane, the monitoring device  70  comprises a pressure sensor  72  that is positioned within the airflow tube  18  (although a particular position for the pressure sensor  72  is shown in  FIG. 7 , it is noted that the pressure sensor, and other sensors described below, can be located in other positions within the airflow tube). The pressure sensor  72  can detect changes in pressure within the airflow tube  18  that are indicative of inhalation and exhalation. Accordingly, the pressure sensor  72  can monitor patient respiration as with the embodiment of  FIGS. 1-5 . 
     In addition to the pressure sensor  72 , further sensors  74  can be provided within the airflow tube  18 . Such can sensors include a temperature sensor configured to measure the temperature of the exhaled air, a humidity sensor configured to measure the humidity of the exhaled air, and a carbon dioxide sensor configured to measure the concentration of carbon dioxide in the exhaled air. 
     Another addition to the monitoring device  70  relative to the monitoring device  10  is the presence of a heat and moisture exchanger (HME)  76  within the airflow tube  18 . As is known in the art, an HME is a component that traps moisture in the patient&#39;s exhaled air and humidifies the air that is inhaled by the patient. By providing moisture to the air that the patient inhales, the HME  76  reduces mucus formation and, therefore, reduces the likelihood for tracheotomy tube occlusion. 
     As identified above, the tracheotomy tube monitoring device can wirelessly transmit signals to other devices for purposes of issuing alerts to relevant parties. The monitoring device can be configured to transmit those signals to a variety of different devices. For example, as shown in  FIG. 8 , a monitoring device  10 ,  70  can be configured to transmit signals to a smart phone  80  or a computer network  82  to which one or more computers  82  are connected. In addition to receiving alerts, the other devices can receive the data collected by the monitoring device  10 ,  70  and perform analysis on that data. Such analysis can comprise analysis as to patient respiration as well as other phenomena relevant to the patient&#39;s health. For instance, data collected by the accelerometer  55  can be used to determine a variety of information about the patient&#39;s health as well as activity. In some embodiments, the various collected data can be used to generate an overall health score for the patient that provides a general indication as to how the patient is doing. In other embodiments, the monitoring system can include a dedicated receiver unit that can be placed in a location in which a person responsible for the patient, such as hospital staff or another caregiver, can hear and/or see an alert generated by the unit. 
     As noted above, various modifications can be made to the disclosed tracheotomy tube monitoring devices in accordance with the present disclosure. For example, the monitoring device can be modified for use with a respirator. Specifically, the monitoring device can be modified such that it can be inserted inline along a respirator tube that delivers air to a patient.