Patent Publication Number: US-2009235936-A1

Title: Valved Fenestrated Tracheotomy Tube Having Inner and Outer Cannulae with Pressure Relief

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This is a related application to U.S. Ser. No. 11/318,649, filed Dec. 27, 2005 and published Jun. 28, 2007 as 2007/0144526. The disclosure of U.S. Ser. No. 11/318,649 is hereby incorporated herein by reference. 
    
    
     FIELD OF THE INVENTION 
     This invention relates to improvements in tracheotomy tubes. 
     BACKGROUND OF THE INVENTION 
     This invention is directed toward the problem of being unable to produce audible laryngeal voice, and thus, the inability to speak, that confronts individuals whose breathing is provided mechanically by a respirator which is connected to a cuffed tracheotomy tube inserted into the trachea of a wearer below the level of the vocal cords. The cuff on the tracheotomy tube is inflated, for example, with air, so that the cuff seals substantially fluid tight against the wall of the trachea. The purposes of the inflated cuff include: to protect against leakage of saliva and other secretions around the tracheotomy tube and into the lungs; and, to prevent the air being delivered under pressure from the respirator through the tracheotomy tube to the lungs and exhalation from the lungs from escaping around the tracheotomy tube and out through the mouth and nose of the wearer. In other words, the inflated cuff provides a closed mechanical respiratory system that completely bypasses the upper airway above the level of the tracheotomy tube, including the vocal cords. The side effects of this include the elimination of exhaled airflow upward through the vocal cords. Of course, this eliminates voice production by exhalation products from the lungs. 
     Currently, there are three available options for individuals being mechanically ventilated via a cuffed tracheotomy tube to produce audible voice and speech with their own vocal cords. The first of these options is described in O. Hessler, M. D., K. Rehder, M. D., and S. W. Karveth, M C, U.S.A., “Tracheostomy Cannula for Speaking During Artificial Respiration,” Anesthesiology, vol. 25, no. 5, pp. 719-721 (1964). There is no known commercially available device constructed as described in Hessler, et al. 
     The second option is a so-called “talking tracheotomy tube,” which is a conventional cuffed tracheotomy tube manufactured with an 8-10 French conduit extending along its length. The distal end of this conduit terminates above the level of the inflated cuff. The proximal end of this conduit is connected to a source of, for example, compressed air. Examples of such a device are manufactured by Sims Portex, Inc., and Bivona Surgical Inc. The wearer of such a device is able to stop and start the flow of compressed air to the distal end of this conduit, thereby enabling the stopping and starting of the flow of air upward through his or her vocal cords, enabling the wearer to produce speech. This speech airflow is completely independent of the respiratory airflow through the tracheotomy tube. Such talking tracheotomy tubes have been available for several years, but are not in widespread use, perhaps owing to numerous mechanical limitations. 
     The third option is systems of the types illustrated and described in U.S. Pat. No. 6,722,367 and U.S. Ser. No. 11/318,649, the disclosures of both of which are hereby incorporated herein by reference. 
     The following are also of interest: U.S. Pat. Nos. 3,688,774; 3,996,939; 4,211,234; 4,223,411; 4,280,492; 4,304,228; 4,449,523; 4,459,984; 4,573,460; 4,589,410; 4,596,248; 4,852,565; 5,056,515; 5,107,828; 5,217,008; 5,255,676; 5,297,546; 5,329,921; 5,339,808; 5,343,857; 5,349,950; 5,391,205; 5,392,775; 5,458,139; 5,497,768; 5,507,279; 5,515,844; 5,584,288; 5,599,333; RE35,595; 5,687,767; 5,688,256; 5,746,199; 5,771,888; 5,957,978; 6,053,167; 6,089,225; 6,102,038; 6,105,577; 6,135,111; 6,463,927; 6,814,007; foreign/international patent publications: DE 25 05 123; DE 37 20 482; DE 38 13 705; DE 195 13 831; WO 99/07428; WO 99/12599; WO 00/32262; other publications: Quick Reference Guide to Shiley&#39;s “Quality-Of Life” Line of Tracheostomy Products, 1991; Granuloma Associated with Fenestrated Tracheostomy Tubes, Padmanabhan Siddharth, MD, PhD, FACS and Lawrence Mazzarella, MD, FACS, Case Reports, vol. 150, August 1985, pp. 279-280; Technical Support Information Connections with the Passy-Muir Tracheostomy and Ventilator Speaking Valves, one sheet; Tracheostomy and Laryngectomy Tubes, pp. 568 and 572; Tracheostomy Tube Adult Home Care Guide, Shiley Tracheostomy Products, Mallinckrodt Medical pp. 1-40; D. Hessler, MD, K. Rehder, MD and S. W. Karveth, MD, “Tracheostomy Cannula for Speaking During Artificial Respiration”, Anesthesiology, vol. 25, No. 5, pp. 719-721 (1964). No representation is intended by this listing that a thorough search of all material prior art has been conducted, or that no better art than that listed is available. Nor should any such representation be inferred. The disclosures of all of the above are hereby incorporated herein by reference. 
     Unless he or she is wearing a device of the type illustrated and described in the above identified U.S. Pat. No. 6,722,367 or U.S. Ser. No. 11/318,649, a ventilator-dependent patient breathing through a cuffed tracheotomy tube is unable to produce audible voice with his or her vocal cords. This is so because without a device of the type illustrated and described in the above identified U.S. Pat. No. 6,722,367 or U.S. Ser. No. 11/318,649, the cuff of the tracheotomy tube he or she wears prevents exhalations from going around the lower end of the tube and upward through the vocal cords. This situation continues until the wearer&#39;s condition improves sufficiently that the cuff on the tracheotomy tube can be deflated so that exhaled air can pass around the tracheotomy tube and up through the wearer&#39;s vocal cords, mouth and nose, permitting audible vocal cord vibrations for speech. 
     The invention alleviates this situation. When coupled to a respirator with its cuff inflated, a valved, cuffed tracheotomy tube system according to the invention directs air on the inhalation cycle of the respirator to the lungs. Exhalations are directed by the valved, cuffed tracheotomy tube system according to the invention to the upper airway, permitting vocal cord vibration and audible laryngeal speech. The lungs of the wearer are protected against overinflation due to obstruction of the upper airway by a valve according to the invention. 
     DISCLOSURE OF THE INVENTION 
     According to an aspect of the invention, an outer cannula has a first port for orienting outside the neck of a wearer, a second port for orienting within the trachea of the wearer, a first passageway coupling the first port to the second port to permit the flow of gases from the first port to the second during inhalation by the wearer and from the second port during exhalation by the wearer, and a third port between the first and second ports. An inner cannula is provided for insertion into the first passageway via the first port when the wearer desires to be able to exhale through the wearer&#39;s pharynx. The inner cannula includes a fourth port for orienting adjacent the first port, a fifth port for orienting adjacent the second port and a second passageway coupling the fourth port to the fifth port to permit the flow of gases from the fourth port to the fifth during inhalation by the wearer and from the fifth port during exhalation by the wearer. A first valve controls flow through the third port. The first valve assumes a first orientation to permit flow from the first port to the second port when the first port is at a higher pressure than the second port and a second orientation to permit flow from the second port when the second port is at a higher pressure than the first port. A second valve assumes a first orientation when the flow of respiration products through the third port is relatively less impeded and a second orientation permitting respiration products to flow from the second port to the first port and out the first port when flow through the third port is relatively more impeded. 
     According to another aspect of the invention, an outer cannula has a first port for orienting outside the neck of a wearer, a second port for orienting within the trachea of the wearer, a first passageway coupling the first port to the second port to permit the flow of gases from the first port to the second during inhalation by the wearer and from the second port during exhalation by the wearer, and a third port between the first and second ports. An inner cannula is provided for insertion into the first passageway via the first port when the wearer desires to be able to exhale through the wearer&#39;s pharynx. The inner cannula includes a fourth port for orienting adjacent the first port, a fifth port for orienting adjacent the second port and a second passageway coupling the fourth port to the fifth port to permit the flow of gases from the fourth port through the fifth during inhalation by the wearer and preventing the flow of gases from the fourth port during exhalation by the wearer. A first valve controls flow through the third port. The first valve assumes a first orientation to permit flow from the fourth port to the fifth port when the fourth port is at a higher pressure than the fifth port and a second orientation to prevent flow from the fourth port when the fifth port is at a higher pressure than the fourth port. A second valve assumes a first orientation when the flow of respiration products through the third port is relatively less impeded and a second orientation permitting respiration products to flow from the second port to the first port and out the first port when flow through the third port is relatively more impeded. 
     Illustratively, the first valve includes a resilient region which lies adjacent the third port when the inner cannula is properly oriented within the outer cannula. The inner cannula further includes a third valve operatively associated with the inner cannula and a region between the resilient region and the third valve which provides a passageway between the inner cannula and the outer cannula when the inner cannula is properly oriented within the outer cannula. 
     Further illustratively, an inflatable cuff is formed on the outer cannula between the second port and the third port. A first conduit extends from adjacent the first port to the cuff for introducing an inflating fluid into the cuff when it is desired to inflate the cuff and removing inflating fluid from the cuff when it is desired to deflate the cuff. The inner cannula includes a second conduit to evacuate a region of a trachea of a wearer adjacent the cuff. The second conduit includes an opening which lies adjacent the closest point in the third port to the cuff when the inner cannula is in a use orientation in the outer cannula. 
     Further illustratively, an inflatable cuff is formed on the outer cannula between the second port and the third port. The inflatable cuff is formed by a sleeve including a first end, a second end and a third region between the first and second ends. The sleeve is located around the outer cannula with at least the first end of the sleeve between the outer cannula and the third region of the sleeve. A conduit extends from a first end of the outer cannula to the cuff for introducing an inflating fluid into the cuff when it is desired to inflate the cuff and removing inflating fluid from the cuff when it is desired to deflate the cuff. 
     Further illustratively, an inflatable cuff is formed on the outer cannula between the second port and the third port. A conduit extends from adjacent the first port to the cuff for introducing an inflating fluid into the cuff when it is desired to inflate the cuff and removing inflating fluid from the cuff when it is desired to deflate the cuff. The third port is oriented immediately adjacent the cuff to permit the flow of gas from inside the outer cannula through the third port and out of the tracheotomy tube. 
    
    
     
       BRIEF DESCRIPTIONS OF THE DRAWINGS 
       The invention may best be understood by referring to the following detailed description and accompanying drawings. In the drawings: 
         FIG. 1  illustrates a fragmentary sectional side elevational view of the upper trachea, lower pharynx and front of the neck of a wearer of a device according to the invention during inspiration of air into the lungs of the wearer under the control of a ventilator; 
         FIG. 1   a  illustrates a perspective view of a detail of the device illustrated in  FIG. 1  in the orientation illustrated in  FIG. 1 ; 
         FIG. 2  illustrates a fragmentary sectional side elevational view of the upper trachea, lower pharynx and front of the neck of a wearer of the device illustrated in  FIG. 1  during normal expiration from the lungs of the wearer upward through the pharynx of the wearer and out the nose and/or mouth of the wearer; 
         FIG. 3  illustrates a fragmentary sectional side elevational view of the upper trachea, lower pharynx and front of the neck of a wearer of the device illustrated in  FIGS. 1-2  during expiration from the lungs of the wearer back through the device illustrated in  FIGS. 1-2  and the ventilator, owing to an obstruction (not shown) of the upper airway of the wearer leading to the nose and mouth; and, 
         FIG. 3   a  illustrates a perspective view of a detail of the device illustrated in  FIGS. 1-3  in the orientation illustrated in  FIG. 3 . 
     
    
    
     DETAILED DESCRIPTIONS OF ILLUSTRATIVE EMBODIMENTS 
     Referring now particularly to  FIG. 1 , a speaking tracheotomy tube system  10  includes an outer cannula  12  for insertion into a tracheostoma  14 . Outer cannula  12  includes an inflatable cuff  16 . Cuff  16  lies in the trachea  18  of a wearer  20  below the passageway  22  upward into the pharynx  24  of the wearer  20 . Outer cannula  12  also includes a first port  26  which resides outside the neck of the wearer  20  during use and a second port  28  which resides inside the neck of the wearer  20  below cuff  16  during use. The cuff  16  is inflatable through a line  30  once the outer cannula  12  is in place in the trachea  18  to minimize the passage of secretions from the upper respiratory tract, including pharynx  24 , downward into the lungs of the wearer  20 . Such secretions pool above the cuff  16  when the cuff  16  is inflated in place, and may be evacuated as illustrated and described in U.S. Ser. No. 11/318,649. 
     The outer cannula  12  includes a pivotally mounted attachment plate  52  adjacent its proximal end  54  to facilitate attachment, for example, by a strap or belt around the neck of the wearer  20 . The outer cannula  12  also includes a fenestration  56  which permits the wearer  20  to speak by providing a flow of exhaled respiratory gases upward through the fenestration  56  and into the pharynx  24 . Speech may then be articulated in accordance with known principles. Although only one such fenestration  56  is illustrated, it should be understood that any number of fenestrations  56  may be provided in the outer cannula  12  for this purpose. 
     During times when the wearer desires to speak, a speaking inner cannula  80  is inserted into the outer cannula  12 . Speaking inner cannula  80  includes a flexible, balloon-like region  82  adjacent fenestration  56 , a region  86  between region  82  and lower end  84  which provides a passageway  87  between region  86  and the inner sidewall of lumen  62  of outer cannula  12 ,  12 ′, and a valve  88  including a resilient flap  90  at its lower end  84 . Speaking inner cannula  80  functions in the following manner when it is inserted into outer cannula  12 , locked in place and its outer end  92  attached to a ventilator  74 . Referring first to  FIG. 1 , during pressurization by the ventilator  74 , balloon-like region  82  inflates, sealing against fenestration  56  and preventing the escape of ventilator-provided air upward through fenestration  56  and the wearer  20 &#39;s pharynx  24 . Flap  90  of valve  88  opens, permitting air to flow into the lungs of the wearer  20 . Referring now to  FIG. 2 , during exhalation, the ventilator  74  removes pressure at the outer end  92  of speaking inner cannula  80 . The flap  90  of valve  88  closes, closing the lumen  94  of speaking inner cannula  80  against the passage upward of respiratory products through speaking inner cannula  80 , permitting the balloon-like region  82  to deflate somewhat and opening passageway  87  upward from the lungs of the wearer  20  through fenestration  56 . Respiratory products in the wearer  20 &#39;s lungs escape upward through passageway  87 , through fenestration  56 , and are released into the wearer&#39;s pharynx  24 , providing sufficient flow to permit the wearer  20  to speak. 
     Speaking inner cannula  80  is releasably fixed to the outer cannula  12  by locking tabs  100  formed with the coupler  104  of cannula  80  by which cannula  80  is coupled to ventilator  74 . The tabs  100  are flexibly formed to effect the appropriate orientation of the balloon-like region  82  of speaking inner cannula  80  with respect to fenestration(s)  56  when speaking inner cannula  80  is inserted into outer cannula  56 . 
     Speaking inner cannula  80  is provided with an additional valve  300  formed by a somewhat C-shaped slit at the similarly somewhat C-shaped transition region between the proximal end of thinner walled, more flexible balloon-like region  82  and the somewhat thicker walled, less flexible upper region of the inner cannula  80 . When speaking inner cannula  80  is in place in outer cannula  12 , valve  300  lies adjacent but proximally, that is toward ventilator  74 , of fenestration  56 . 
     As noted above, and with reference again to  FIG. 1 , in use, during the inhalation portion of the ventilator  74  cycle, air is pumped by the ventilator  74  through inner cannula  80  into the lungs of the wearer  20 . Pressurization of inner cannula  80  inflates balloon-like region  82  against the inner sidewall of outer cannula  12 , closing fenestration  56 , thus preventing the escape of air upward through the pharynx  24  of the wearer  20 . Additionally, valve  300  is sealed against the inner sidewall of outer cannula  12  by this same inflation pressure. The flap  90  of valve  88  opens, and the air flows into the lungs of the wearer  20 . With reference again to  FIG. 2 , then during the exhalation portion of the ventilator  74  cycle, pressure at the outer end  92  of outer cannula  12  is removed. Flap  90  of valve  88  closes, balloon-like region  82  deflates away from fenestration  56 , opening fenestration  56 . Respiratory products flow upward past balloon-like region  82 , through fenestration  56 , and upward through the pharynx  24  of the wearer  20  permitting speech. 
     With reference now to  FIG. 3 , there is a remote possibility that the upper airway through the pharynx  24  of the wearer  20  can become obstructed, for example, by secretions or the like which the wearer  20  is unable to develop sufficient coughing pressure to expel, by mispositioning or misfitting of outer cannula  12 , or other causes. Thus, there is a remote possibility that the next inhalation cycle of the ventilator  74  will begin without exhalation products from the previous exhalation cycle having been expelled. In this event, a second inhalation cycle of the ventilator  74  will pump the next volume of air through inner cannula  80  and into the lungs of the wearer  24  as described above. After this second inhalation cycle, the lungs of the wearer  20  have become somewhat overinflated. The lungs of the wearer  20  and the wearer  20 &#39;s upper trachea will have become sufficiently pressurized that valve  300  will open by deflection of valve  300  flap inward toward the center of inner cannula  80  and away from the inner wall of outer cannula  12  to permit respiration products to return back through the proximal end  92  of cannula  12  and the ventilator  74  to relieve the excess pressure on the lungs of the wearer  20  and prevent overinflation damage to the lungs of the wearer  20 .