Patent Publication Number: US-2006000476-A1

Title: Retaining system for securing a ventilation mask

Description:
RELATED APPLICATIONS  
      This application is a continuation of U.S. Provisional Patent Application No. 60/585,422 entitled “Ventilation System For Intermittent Positive Pressure Ventilation Masks,” filed on Jul. 1, 2004, and naming M. Ramez Salem as inventor, which application is incorporated entirely herein by reference. 
    
    
     FIELD OF THE INVENTION  
      The present invention relates to ventilation masks and in particular to retainers for securing a ventilation mask to a user. In preferred embodiments, the present invention is directed to ventilation systems that comprise a mask to be used for intermittent positive pressure ventilation or spontaneous breathing ventilation, and a retainer.  
     BACKGROUND OF THE INVENTION  
      Ventilation masks, such those used with intermittent positive pressure ventilation (IPPV) and spontaneous breathing ventilation, are employed for a variety of medical applications. For example, when a patient receives anesthetic gas during a medical operation, the gas typically will be delivered through a mask using intermittent positive pressure ventilation. Unlike other types of masks, such as continuous positively airway pressure (CPAP) masks, masks used for intermittent positive pressure ventilation are oronasal masks that cover both a patient&#39;s face and nose, in order to completely access the patient&#39;s airways. The anesthetic gas then is delivered through the mask with either intermittent positive pressure or spontaneous breathing. These ventilation masks thus are used with intermittent positive pressure ventilation masks and spontaneous breathing ventilation to provide patients with anesthetic gases and oxygen.  
       FIGS. 1A and 1B  illustrate a conventional intermittent positive pressure ventilation mask  101 . As seen in these figures, the mask  101  includes a dome  103 , a balloon cushion  105 , a cushion valve  107 , and a hose connector  109 . The dome  103  is open at the bottom so as to form a cup, and typically is made from a hard plastic or similar material. As seen in  FIG. 1B , the dome  103  may have a pear or oval shape, so that it can comfortably cover both a patient&#39;s nose and mouth at the same time. The balloon cushion  105  comprises a bag or roll of soft, flexible material that extends around the periphery of the dome  103 . Air can be introduced into the inside of the balloon cushion  105  through the cushion valve  107 .  
      The hose connector  109  connects to a hose through which the desired gas is delivered into the mask  101 , and forms an aperture into the inside of the dome  103 . The hose connector  109  is sized to securely fit the hose delivering the desired gas into the mask  101 . As shown in  FIGS. 1A and 1B , the dome  103  includes a flattened extremity that forms a shelf  111  around the hose connector  109 . The shelf  111  facilitates the use of a conventional retaining system for holding the mask  101  in place on a patient&#39;s face. As shown in  FIGS. 2A and 2B , a post ring  201  (sometimes also referred to as a “hook ring” or “collar ring”) is employed by this conventional retaining system. The post ring  201  includes a base  203  and four posts  205  extending from the base  203 . As seen in these figures, the post ring  201  is positioned such that the base of the post ring  201  rests on the shelf  111  of the dome  103 . In this position, the posts  205  extend from the post ring  201  away from the dome  103 . This conventional retaining system also employs a retainer, such as the retainer  301  shown in  FIG. 3  ( FIG. 3  is not drawn to scale). The head band  301  includes a central portion  302  and two pairs of opposing extensions  303 . Each extension  303  includes a plurality of perforations  305  that are generally evenly spaced apart and that are disposed along at least a portion of the length of the extension  303 .  
      To secure the mask  101  to a patient&#39;s face, the central portion  302  of the head band  301  is positioned behind the patient&#39;s head. After the mask  101  has been placed on the patient&#39;s face at the desired position, each of the extensions  303  is drawn around the patient&#39;s head to extend over the post ring  201 . More particularly, as shown in  FIG. 4 , each extension  303  is positioned over a post  205  so that the post  205  passes through a perforation  305  in the extension  303 . The extensions  303  generally are formed from an elastic material, and the perforations  305  are sized to receive the posts  205  in a manner that allows each post  205  to be elastically retained with respect to the respective engaging extension  303 . By selecting the perforation  305  that is to receive the post  205  corresponding to the extension  303 , a medical care provider can control the tension of the extension  303 . In this manner, the mask  101  may be securely retained on the patient&#39;s face.  
      While this conventional retaining system is commonly employed, it suffers a number of drawbacks and disadvantages. Unlike CPAP masks, which typically are used in a home environment and manipulated by the patient, masks used for intermittent positive pressure ventilation and spontaneous breathing ventilation typically are employed in a hospital or other professional medical environment. Accordingly, the medical service provider using these masks should secure the mask to the face of a patient while wearing surgical gloves. The conventional retainer  301  was developed before the use of surgical gloves by anesthetists was common, and thus is difficult to use while wearing surgical gloves.  
      There are still other disadvantages to conventional mask retaining systems; for example, the post ring  201  is a separate component from the mask  101 , and must be manufactured separately, thus increasing manufacturing costs. Additionally, the post ring  201  easily can become lost or disassociated from the mask  101 .  
      Still further, depending upon the spacing between the perforations  305  formed in the extensions  303 , the medical care provider may be forced to choose between positioning the extensions  303  with too much tension and positioning the extensions  303  with too little tension. If the extensions  303  are fastened to the posts  205  with too much tension, the mask  101  will be forced down against the patient&#39;s face, creating discomfort for the patient. Alternately, if the extensions  303  are fastened to the posts  205  with too little tension, the mask  101  may not be securely pressed against the patient&#39;s face, and thus may come loose.  
     BRIEF SUMMARY OF THE INVENTION  
      Various embodiments of the invention provide a mask, preferably for use with intermittent positive pressure ventilation or spontaneous breathing ventilation, and an associated retainer that allows the mask to be securely and comfortably held against a patient&#39;s face. The mask and retainer together form a ventilation system. In accordance with the invention, a mask is provided with a retaining strip that comprises one mating portion of a mating hook-and-loop fastener system. A retainer corresponding to the mask includes the other mating portion of the hook-and-loop fastener system. Accordingly, when the hook-and-loop material on the retainer is mated with the corresponding hook-and-loop material provided on the mask, the mask will be securely held in place on the patient&#39;s face. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       FIG. 1A  is a side elevation of a conventional mask for use with intermittent positive pressure ventilation.  
       FIG. 1B  is a plan view of the conventional mask for use with intermittent positive pressure ventilation shown in  FIG. 1A .  
       FIG. 2A  is a perspective view of the mask shown in  FIGS. 1A and 1B , including a post ring disposed in a normal operating position with respect to the mask.  
       FIG. 2B  is a plan view of the mask and post ring as illustrated in  FIG. 2A .  
       FIG. 3  is a perspective view (not to the same scale as  FIGS. 1A, 1B ,  2 A, and  2 B) of a retainer used with a conventional mask.  
       FIG. 4  is a plan view of a conventional ventilation system that includes the mask illustrated in  FIGS. 1A and 1B , shown with the retainer illustrated in  FIG. 3  in an operating position.  
       FIG. 5A  is a side elevation of mask for use with intermittent positive pressure ventilation in accordance with the invention.  
       FIG. 5B  illustrates a plan view of the mask shown in  FIG. 5A .  
       FIG. 6  (not to the same scale as  FIGS. 5A and 5B ) is a plan view of a retainer useful in connection with the mask shown in  FIG. 5 .  
       FIG. 7  is a partial front elevation, enlarged with respect to  FIG. 6 , of the retainer shown in  FIG. 6 .  
       FIG. 8  is a plan view of the ventilation system of the invention, including the mask shown in  FIGS. 5A and 5B  and the retainer of  FIG. 6 , the retainer being shown in an operating position. 
    
    
      It should be understood that references herein to the orientation of the mask and retainer in the various views are for the purposes of providing relative descriptions; in practice, the mask and retainer may be employed omnidirectionally.  
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
      As seen in  FIGS. 5A and 5B , the mask  501  includes a dome  503 , a balloon cushion  505 , a cushion valve  507  and a hose connector  509 . The dome  503  is open at the bottom so as to form a cup. The dome  503  may be made from any desirable material, such as, for example, a hard plastic, rubber, or similar material. The dome  503  should be formed with a material that will not react (or will not strongly react) in normal use with the desired gas intended to be provided through the mask  501 . As seen in  FIG. 5B , the dome  503  may have a pear or oval shape, so that the dome  503  can be comfortably placed over both a patient&#39;s nose and mouth at the same time. It should be appreciated, however, in other embodiments of the invention the dome  503  may have a different shape.  
      The balloon cushion  505  may be formed from any suitable material. The balloon cushion  505  extends around the periphery of the dome  503 . In the illustrated embodiment, the balloon cushion  505  is formed of a bag or roll of a soft, flexible material, such as a soft plastic. In this embodiment, air (or another suitable gas) can be introduced into the balloon cushion  505  through the cushion valve  507 , to inflate the balloon cushion  505 . The cushion  505  alternatively may be composed of any suitable alternative cushioning material, such as a solid gel, a solid piece of soft material (such as rubber), or a combination of different structures.  
      The hose connector  509  connects to a hose (not shown) through which the desired gas is delivered into the mask  501 . The hose will be connected to the breathing circuit of an anesthetic system or a resuscitation bag. These types of anesthetic systems and resuscitation bags are well known in the art, and thus will not be discussed here in further detail.  
      Returning now to  FIG. 5 , the hose connector  509  forms an aperture into the inside of the dome  503 . The hose connector  509  is sized to be securely fitted to the hose that delivers the desired gas into the mask  501 , generally via the use of a suitable fitting. In the illustrated embodiment, the dome  503  includes a shelf  511  surrounding the hose connector  509 . While the shelf  511  is not necessary in the context of the invention, by employing this configuration the mask may be manufactured using the same molds and tooling as are used to manufacture conventional masks employed for intermittent positive pressure ventilation. The shelf  511  alternatively may be omitted from the dome  503 .  
      As also seen in  FIGS. 5A and 5B , the mask  501  is provided with retaining strips  513 ,  515 , each of which comprises a first mating portion of a pair of mating portions of a hook-and-loop fastener system. The hook-and-loop material for this type of fastener system may be formed from an array of closely spaced hook structures or, alternately, from an array of closely spaced structures forming loops. When a layer of hook-and-loop fastener material formed from closely spaced hooks is pressed against a layer of hook-and-loop fastener material formed from closely spaced loops, the hooks will hook around the loops, thereby removably fastening the two layers together. Hook-and-loop fastener materials are commercially available, for example, under the trademark VELCRO®. The retaining strips are preferably fastened to the mask using adhesive.  
      As seen in  FIG. 6 , the retainer  601  includes a plurality of extensions  603 . In the illustrated embodiment, the retainer  601  includes two pairs of opposing extensions  603 . The retainer  601  may be formed of an elastic material, such as rubber, leather, or other suitable material. As shown in  FIGS. 6 and 7 , each extension  603  is provided with a retaining strip  701  that comprises a second mating portion of a pair of hook-and-loop fasteners, the second mating portion being mateably and releasably engagable with the first mating portions of the strips  513 ,  515  on the mask  501 . The strips  701  preferably are secured to the retainer with adhesive.  
      In operation, such as during a medical operation (e.g., for the induction of an anesthetic gas before a surgical procedure or for the emergence of the patent from an anesthetic after a surgical procedure), the center portion of the retainer  601  (not shown in  FIG. 8 ) is placed behind the patient&#39;s head. After the mask  501  is placed at a desired position on the patient&#39;s face, the medical care provider draws each of the extensions  603  around the patient&#39;s face and over the mask  501 , so that each retaining strip  701  of hook-and-loop fastener material engages one of the retaining strips  513  and  515  of the mask  501 , as shown in  FIG. 8 . In this manner, the mask  501  will be securely held to the patient&#39;s face. The medical care provider can then perform a medical procedure on the patient after the patient has received the gases as desired (or the patient can emerge from an anesthetic after the medical procedure has been completed).  
      The mask and retainer thus form a ventilation system, by which is contemplated a system that allows any desired gas to be supplied to a patient. This system offers a number of advantages over the prior art. For instance, the mask readily may be secured using one hand, and can easily be secured by a person wearing protective gloves. The position of each extension  603  relative to the mask  501  may be changed in very small increments, thereby allowing the medical care provider to optimize security and comfort. Moreover, by extending the retaining strips  701  over a substantial portion of the length of the extensions  603 , a single size retainer  601  can be used with patients with a variety of different head sizes. After use, the mask  501  can be discarded or sterilized for future use.  
      While particular embodiments of the invention have been described in detail above, it should be appreciated that various other embodiments of the invention may have alternate or additional features. For example, in the illustrated embodiments, each extension  603  has only a single retaining strip  701  of a hook-and-loop fastener material provided on one side of the extension  603 . In alternate embodiments of the invention, however, a retaining strip  701  of a hook-and-loop fastener material may be provided on each side of one or more of the extensions  603 . By providing a retaining strip  701  of hook-and-loop fastener material on both sides of the extensions  603 , a medical provider will not need to adjust the orientation of the extensions  603  prior to use.  
      Also, while  FIGS. 5A, 5B  and  8  show the use of two retaining strips  513  and  515  of a hook-and-loop fastener material disposed on the mask, still other embodiments of the invention may employ a single strip of hook-and-loop fastener material arranged over the mask  501  or conversely three or more strips of hook-and-loop fastener material arranged over the mask  501 .  
      Also, while particular examples of the invention have been described with respect to a mask used for intermittent positive pressure ventilation, it should be appreciated that various embodiments of the invention may be employed to securely retain other types of oronasal ventilation masks that fit over the patient&#39;s nose and mouth. Further embodiments of the invention may include alternate or additional modifications and features. Accordingly, the invention should not be deemed limited in scope to the preferred embodiments described herein, and all suitable modifications and equivalents should be considered as falling with the scope of the appended claims.