Abstract:
A nasal cannula apparatus is provided for use by patients desiring a comfortable arrangement. The nasal cannula apparatus is particularly suited for long-term oxygen users, for extended wear in both standing, resting and supine positions. The nasal cannula apparatus has headgear and retainers for holding the gas supply tubes, which are adjustable to allow fast and easy adjustment to size. The headgear and retainers allow the cannula tubes to be held in a position which prevents skin discomfort and irritation, and which promotes healing of such irritation, injuries and sores.

Description:
The following application claims priority under 35 U.S.C. 119(e) of Provisional Application No. 60/401,193, filed Aug. 6, 2002 

   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to nasal cannula apparatus for use by patients, desiring a comfortable arrangement. The nasal cannula apparatus is particularly suited for long-term oxygen users, for extended wear in both standing, resting and supine positions. The nasal cannula apparatus has headgear and retainers for holding the gas supply tubes, which are adjustable to allow fast and easy adjustment to size. The headgear and retainers allow the cannula tubes to be held in a position which prevents skin discomfort, irritation, blisters, abrasions, pressure sores and other injuries and promotes healing of such irritation, injuries and sores. 
   2. Description of the Prior Art 
   There are a number of persons requiring supplemental oxygen such as after surgery to aid in the healing process, and persons having lungs of limited capacity due to disease or lung damage which require supplemental oxygen to assist in everyday life. These people having respiratory problems are typically assisted in breathing by providing a gas source, which provides pressurized ambient or oxygen enriched air to the lungs of the patient via a nasal cannula. A typical arrangement for a cannula apparatus is illustrated in U.S. Pat. No. 3,726,275, Jackson et al., entitled “Nasal Cannulae”. The nasal cannula comprises essentially a nasal assembly, or nosepiece, with a hollow main body having two directed orifices near or in a patient nostrils. Typically, the orifices consist of nasal extension tubes extending upwardly from a main body portion and gas is supplied through supply tubes to the main body, which acts as a distributing manifold. Commonly, the cannula nosepiece is held in place by extending the gas supply tubes from the patient&#39;s nasal area to behind the patient&#39;s ears. The flexible tubes are bent downward behind the ears to run along the jaw area, and are held in place by an adjustable slip loop or a cinch tightened below the chin to hold the nosepiece in place. Oxygen or other gas flows through the tubes to the two orifices, thereby supplying the patient with pressurized ambient or oxygen enriched air. 
   While being one of the most convenient methods known to date for supplying a patient with a gas enriched environment, existing nasal cannulae suffer a major drawback: the positioning of the tubes around the ears for support is uncomfortable and can cause the patient chaffing and pain. Additionally, existing nasal cannulae are prone to falling off the patient&#39;s face. Patients regularly find that body movement, especially during sleep, causes the cannula to dislocate, depriving the patient of the needed oxygen enrichment. Accidental removal of the cannula can also cause severe discomfort to the patient and in certain cases may even be life threatening. 
   As a means of preventing movement of the cannula from within the nasal passages of the patient, numerous devices are known to the prior art for stabilizing the cannula with respect to the patient. Some devices employ the gas supply tubes that supply air from the respirator to the cannula for holding the cannula in place. For example, in U.S. Pat. No. 3,915,173 to Brekke, a cannula assembly is shown wherein portions of the gas supply tubes are seated on the bridge of the patient&#39;s nose. In U.S. Pat. No. 2,693,800, the gas supply tubes are passed over the ears of the patient. 
   U.S. Pat. No. 2,168,705, Francisco et al., entitled “Nasal Inhaler”, discloses a support for cannula tubes having temples which clasp behind the wearer&#39;s ears and include nose pads of the type used with eyeglasses. The use of temples and nose pads also makes this arrangement uncomfortable and not well suited for use while the wearer is sleeping. 
   U.S. Pat. No. 2,259,817, Hawkins, entitled “Adjustable Head Attachment for Oxygen Tubes” discloses a support for cannula tubes having an adjustable temple band and an adjustable crown band These bands and associated buckles, together with the obtrusive nose portion of the cannula tube also make this arrangement uncomfortable and unsuitable for sleeping. 
   U.S. Pat. No. 4,559,941, Timmons et al, entitled “Eyeglass Frame and Nasal Cannula Assembly”, discloses a cannula apparatus which supports and substantially conceals the cannula tubes by eyeglass frames. That arrangement is not well suited for use while the wearer is sleeping. In addition, some individuals who do not wear glasses for reasons of vision find glasses uncomfortable or awkward and would prefer another nasal cannula arrangement. 
   U.S. Pat. No. 4,808,160 to Timmons, et al discloses a “Nasal Cannula Apparatus” comprising a headband with a cannula junction thereon from which nasal tubes extend downwardly across the face on either side of the nose, and curve up into the nostrils. This arrangement is uncomfortable against the face and can block or impair ones vision. 
   U.S. Pat. No. 4,774,946 to Ackerman, et al discloses a “Nasal and Endotracheal Tube Apparatus” for use with infants comprising bulbous nasal tubes and a headband yoke for clipping corrugated supply tubes thereto. This arrangement is uncomfortable in the nasal passages and is not compatible with standard supply tubes. 
   U.S. Pat. No. 4,367,735 to Dali discloses a “Nasal Cannula” with ribbed nose prongs attached to a foam base for attachment to a skullcap. The foam base, which extends across the face is bulky and can also be uncomfortable as well as obstructive. 
   U.S. Pat. No. 4,699,139 to Marshall, et al, U.S. Pat. No. 4,949,733 to Sampson, U.S. Pat. No. 5,400,776 to Bartholomew, and U.S. Pat. No. 6,026,811 to Settle, all teach devices that fit around the supply tubes and are placed on or around a patients ears. These devices are used to maintain a bend in a tube and/or provide padding for comfort about the ears. U.S. Pat. No. 6,434,796 to Speirs also teaches an “Oxygen Delivery Cannula Retainer, Cannula With Retainers Assembly, And Method For Retaining Cannulas” comprising a device securable about a patients ears. Although meant to provide comfort, these devices still create chaffing and discomfort due to placement about the patient&#39;s ears. 
   U.S. Pat. No. 5,636,630 to Miller et al., U.S. Pat. No. 4,836,200 to Clark, U.S. Pat. No. 4,422,456 to Tiep, and U.S. Pat. No. 6,298,850 to Argraves, all attempt to solve this problem. Miller et al. discloses running the tubes behind the patient head and utilizing a coupling portion contacting the back of the head, with the gas conduits passing in criss-cross manner behind the head. This arrangement suffers from several disadvantages, major amongst them is the location of both oxygen tubes behind the patient&#39;s head where they may be blocked if the head is resting thereupon. Additionally, placement of tubes behind the head is often uncomfortable to the patient. 
   The Clark patent utilizes a pressure-fastening strap adapted to go over the top of a user&#39;s head, onto which the flexible tubes are attached. Clark&#39;s preferred implementation is less desirable since the strap may slide over the head of the user and is liable to entangle with the patient&#39;s hair. 
   Tiep and Argraves disclose means for supporting the cannula in place by an elastic band that is adjustably connected to two holders each located on one of the conduits or flexible tubes. An elastic band extending behind the patient&#39;s head is secured to the tubes. A problem with these inventions is that the elastic band runs the risk of entanglement in the patient&#39;s hair. 
   The major problem with the cannulas and retainers of the prior art is that they rub on the face and ears of a patient under extended use. This rubbing causes discomfort, chaffing, sores and infections, particularly in elderly patients and other with heightened sensitivity such as chemotherapy patients. The retainers and pads of the prior art are also obtrusive, uncomfortable and unattractive and do not particularly alleviate the chaffing of the skin of the face and ears. 
   Another major problem with such prior art cannula occurs when the main oxygen delivery tube which delivers oxygen to the cannula gets snagged on an object, which happens frequently during the course of a day for a mobile person such as when carrying or pulling a portable oxygen tank or a person connected by a long main tube to a stationary oxygen concentrator located in a house or apartment. When such snagging occurs, the oxygen tubes are typically pulled downwardly such that the tension on the upper portions of the oxygen tubes is significantly increased jamming the nosepiece into the person&#39;s nose causing much discomfort to such person and potential injury to the nose, ears, and face of the person. Such snagging also causes the upper portions of the respective oxygen tubes to move upwardly towards the person&#39;s eyes partially blocking the field of view, which can be particularly hazardous while driving an automobile. 
   Another problem is that the retaining collars are prone to slip downwardly during cannula use such that the tension on the oxygen tubes is reduced. Such loss of tension can cause the nosepiece to fall from the person&#39;s nose and the oxygen tubes to fall from around the person&#39;s ears. This is particularly prone to occur when the person is asleep and is typically caused by tossing and turning of the person causing contact of the cannula and retaining collar against the bed. The person generally awakes when the nosepiece dislodges or falls from the person&#39;s nose due to the insufficient supply of oxygen to the person&#39;s brain, and the person must subsequently reattach the cannula. This activity disrupts the person&#39;s sleep particularly when occurring multiple times each night. If the person does not awake, potentially serious hypoxia, including permanent brain damage and death can occur due to the lack of sufficient oxygen supply to the person&#39;s brain. 
   Thus, there is a need for a means and method for retaining a cannula in place during use, to particularly prevent the chaffing of the ears and face, and for preventing painful tugging on the oxygen tubes jamming the nose piece into the person&#39;s nose, particularly while the person is awake and active. 
   It is clear therefore that a need exists for a device to secure a nasal cannula to a patient&#39;s head in a light, inexpensive, and effective manner, and doing so in a manner that will be unobtrusive to the patient. Additionally, a better solution is needed for providing user comfort in the nasal septum and other facial areas as described above. The current invention discloses such a device and method for its use. 
   SUMMARY OF THE INVENTION 
   According to the present invention, there is provided a cannula retainer that keeps the cannula off of the ears and face of the patient, thereby eliminating skin irritation caused by other cannulas and retainers. The disclosed invention retains the cannula supply tubes on holders mounted to a headpiece such as a hat, cap or headband. The holders comprise a pair of grooved retainers that are adjustably attached to the headpiece. The headpiece or cap is also adjustable in order to fit a variety of head sizes. 
   The preferred embodiment of the invention provides an adjustable cap having hook and loop fastener material affixed thereto. The hook and loop fasteners may be engaged and disengaged from the grooved round dowels also having hook and loop fasteners affixed thereto, thereby providing a means for attachment and adjustment of the retainers on the cap or headpiece. The cannula tubes are placed on the retainers and are held thereon in the grooves and tend from the retainers such that they do not rub on the patient&#39;s ears or face. Thus, the cap and retainers may be adjusted to a position suitable for a patient&#39;s head size and/or position of comfort for the cannula tubes. 
   Its is therefor an object of the present invention to provide a cannula retention apparatus that provides a comfortable retainer for a cannula, and minimizes discomfort of the patient wearing the cannula. 
   It is another object of the present invention to provide a device of the character described wherein the cannula supply tubes are not positioned around the ears for support. 
   It is another object of the present invention to provide a device of the character described that is not prone to falling off the patient&#39;s face. 
   It is another object of the present invention to provide a device of the character described wherein the cannula does not cause the patient chaffing or pain. 
   It is another object of the present invention to provide a device of the character described wherein the patient&#39;s body movement does not cause the cannula to dislocate. 
   It is another object of the present invention to provide a device of the character described wherein the cannula tubes are not seated on the bridge of the patient&#39;s nose or other parts of the face. 
   It is another object of the present invention to provide a device of the character described wherein the tube or retainers do not block or impair ones vision. 
   It is another object of the present invention to provide a device of the character described wherein foam or base does not extend across the face. 
   It is another object of the present invention to provide a device of the character described which is not bulky or obstructive. 
   It is another object of the present invention to provide a device of the character described which does not secure behind the head. 
   It is another object of the present invention to provide a device of the character described wherein the tubes may not be blocked by the head in resting position. 
   It is another object of the present invention to provide a device of the character described wherein the retainer or tubes are not liable to entangle with the patient&#39;s hair. 
   It is another object of the present invention to provide a device of the character described wherein that does not rub on the face and ears of a patient under extended use. 
   It is another object of the present invention to provide a device of the character described wherein the device does not cause discomfort, chaffing, sores and infections, particularly in elderly patients and other with heightened sensitivity such as chemotherapy patients. 
   It is another object of the present invention to provide a device of the character described wherein the cannula is not prone to snagging on objects. 
   It is another object of the present invention to provide a device of the character described wherein the tension on the upper portions of the oxygen tubes is controllable. 
   It is another object of the present invention to provide a device of the character described wherein the controlling tension of the device prevents jamming of the nosepiece into the person&#39;s nose. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The above and other objects and advantages of the present invention will be apparent upon consideration of the following detailed description, taken in conjunction with accompanying drawings, in which like reference characters refer to like parts throughout, and in which: 
       FIG. 1  is a perspective view of a cannula with ear pads of the prior art; 
       FIG. 2  is a perspective view of one embodiment of the cannula and retainer of the present invention; 
       FIG. 3  is a perspective view of an alternate adjustable headpiece configuration for the cannula retainer; 
       FIG. 4  is a plan view of an adjustable retaining dowel as in  FIG. 3 ; 
       FIG. 5  is an elevation view of the adjustable retaining dowel of  FIG. 4 , having a central groove therein; 
       FIG. 6  is an elevation view of an alternate adjustable retaining dowel as in  FIG. 4 , having a proximal groove therein; 
       FIG. 7  is a plan view of an alternate adjustable retainer; 
       FIG. 8  is an elevation view of an alternate adjustable retainer as  FIG. 7 ; 
       FIG. 9  is a plan view of an another alternate adjustable retainer; 
       FIG. 10  is an elevation view of the adjustable retainer of  FIG. 9 , having a central groove therein; and 
       FIG. 11  is an elevation view of the adjustable retainer of  FIG. 9 , using direct attachment of fasteners to the proximal face of the retainer. 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENT 
   The present invention provides an apparatus for retention of a nasal cannula. The nasal cannula comprises essentially a nasal assembly  18 , or nosepiece, with a hollow main body  15  having two directed orifices  16 ,  17  near or in a patient nostrils. The orifices consist of nasal extension tubes  16 ,  17  extending upwardly from a main body portion  15  and gas is supplied through supply tubes  11 ,  12  to the main body  15 , which acts as a distributing manifold to the extension tubes  16 ,  17 . Oxygen or other gas flows through the tubes  11 ,  12  to the two orifices  16 ,  17 , thereby supplying the patient with pressurized ambient or oxygen enriched air. 
   In the prior art, the cannula nosepiece  18  is held in place by extending the gas supply tubes  11 ,  12  from the patient&#39;s nasal area behind the patient&#39;s ears. The flexible tubes  11 ,  12  are bent downward behind the ears to run along the jaw area, and are held in place by an adjustable slip loop or a cinch  13  tightened below the chin to hold the nosepiece  18  in place. 
   In the present invention, the cannula nosepiece  18  is held in place instead by extending the gas supply tubes  11 ,  12  from the patient&#39;s nasal area to the supply tube retainers  21 ,  22  mounted above the patient&#39;s ears on a hat, cap, headband, headpiece  1  or the like. The flexible tubes  11 ,  12  are bent downward around the grooved retainers  21 ,  22  to run downwardly, and may be held in place by an adjustable slip loop or a cinch  13  tightened below the chin to hold the nosepiece  18  in place. Preferably, the tubes  11 ,  12  are extended from the nosepiece  18 , and a loop is formed tending behind and around grooves the retainers  21 ,  22 , then downwardly towards the tube junction  14  and cinch  13 . This provides a secure holding point for each supply tube  11 ,  12 , not only from the friction provided by each groove against each tube  11 ,  12 , but also from the friction of the contact between the tubes  11 ,  12  in the looped portion of below the retainers  21 ,  22 . Alternately, the tubes  11 ,  12  may be extended from the nosepiece  18 , and tend from the front to the back around the grooves the retainers  21 ,  22 , then downwardly towards the tube junction  14  and cinch  13 . 
   Referring to  FIG. 2 : In the preferred embodiment of the invention, the cannula retention apparatus comprises a type of hat  1  or headgear  1  that a person can comfortably wear on their head. The embodiment in  FIG. 2  shows a typical baseball type cap  1 . The cap  1  comprises an adjustable headband  5  having a crown portion  6  affixed thereto. The headband  5  adjusts to fit the radius of the person&#39;s head and the crown  6  provides material covering the top of the head surrounded by the headband  5 . The crown portion  6  essentially covers the head while providing a means of preventing the headband  5  from slipping lower on the head. The crown portion  6  may be made of typical hat materials including cotton, polyester, nylon, felt, straw, plastic, paper or other material appropriate to the type of hat construction. The baseball style of cap  1  (as well as other types) also generally has a visor  7  attached to the front portion of the headband  5  and crown  6  and provides a means of keeping sunlight out of ones eyes. 
   The headband  5  may be adjustable to fit a variety of head sizes. The adjustable headband  5  is preferably constructed from an elasticized material. Further adjustability may be provided by using hook and loop fasteners (VELCRO), snaps, eyelets, laces, buckles or other conventional fasteners. For elasticized embodiments of the headband  5 , the elasticized material may comprise any portion of or the entirety of the headband  5 . For the other types of fasteners, these fasteners are preferably located at the rear of the headband  5 , opposite the visor  7 . Complimentary fasteners at the rear of the headband  5  are preferably located on detachable/attachable ends  51 ,  52  of the headband  5  to provide the adjustment capability. 
   Wherein the embodiment of the invention shown in  FIG. 2  illustrates a baseball type of cap  1 , many other types of headgear  1  are envisioned for use in the cannula retainer, including but not limited to: hats for men, women, or children; hospital caps; golf caps; tennis caps; fishing hats; western hats; men&#39;s and women&#39;s dress hats, derbies; fedoras; bonnets; helmets; construction hard hats; straw hats; visor-less caps; berets; winter hats; and any variety of hats on or within which retainers  20  may be attached. 
   Referring again to  FIG. 2 : The cannula retention assembly further comprises retainers  20  which in this embodiment comprise a pair of dowels  21 ,  22  attached to the headband  5  of the cap  1 . The dowels  21 ,  22  may be attached by pop riveting, gluing, sewing, screwing or otherwise to the headband  5  and or crown  6  of the cap  1 . In the most preferable embodiment of the invention, the dowels  21 ,  22  are connected to the cap  1  using hook and loop fasteners (such as VELCRO). For example, a length loop fastener material  32  may be sewn or glued to the headband  5  and/or crown  6  of the cap  1 , while the dowels  21 ,  22  may be attached to a segment of hook material  80 . This allows the dowels  21 ,  22  to be placed anywhere along the length of loop material  32 , which provides the ability to adjust the dowels&#39;  21 ,  22  placement to one&#39;s preferences. The hook material  32  may extend around the whole circumference of the headband  5  to maximize adjustability of the dowels  21 ,  22 . However, in the preferred embodiment of the invention a first length of loop (or hook)  32  material is sewn or glued from the right edge of the visor  7  around the headband  5  to the area of the headband  5  just behind the right ear. Likewise, a second length of loop (or hook) material  32  is sewn or glued from the left edge of the visor  7  around the headband  5  to the area of the headband  5  just behind the left ear. 
   Referring now to  FIGS. 4–6 : The retainers  20  comprising dowels  21 ,  22  are preferably constructed so as to retain supply tubes  11 ,  12  and a nasal cannula nosepiece  18  therebetween, and to be adjustable as to their location on the headband  5  or crown  6  of the cap  1 . Since dowels  21  and  22  are essentially identical, the description herein of the first dowel  22  applies equally to the second dowel  21 , and for simplicity is identified as dowel  40  in the  FIGS. 4–6 . The dowel  40  preferably comprises a rounded structure with a groove  45  therein, which is adapted to retain a cannula supply tube  11  or  12  therein, without bending or blocking the tube  11 ,  12 . In the embodiment of the dowel  40  of  FIGS. 4–6 , the dowel  40  comprises a cylindrical block of material. The cylindrical block may be constructed from wood, plastic, metal, leather, rubber, cardboard, foam rubber, resilient Styrofoam, polystyrene or any material sufficiently rigid to support the supply tubes  11  or  12  and cannula nosepiece  18  therebetween. To maximize comfort to the wearer and provide a more secure attachment point to the cap  1 , the dowels  40  are preferably constructed of a light and rigid material such as foam rubber, which is not only light, but also simplifies assembly because of the ability to easily fabricate a dowel using a punch. The diameter of the cylinder is preferably between 0.5–2.0 inches to provide a light dowel  40  that has a sufficient diameter to preclude bending of a cannula tube  11 ,  12  supported thereby. The height of the cylinder is at least as wide as the diameter of a standard cannula tube  11 ,  12  and preferably at least twice as wide as the cannula tube  11 ,  12  diameter, or approximately 0.3–1.0 inches. 
   The cylindrical dowel  40  also has a circumferential groove  45  therein. The groove  45  may be centered between the proximal  41  and distal  43  circular portions of the dowel  40  as in  FIG. 5 , but is preferably located at the proximal side  41  of the dowel  40  as in  FIG. 6 . The depth of the groove  45  must be sufficient to retain a cannula tube  11 ,  12  therein. More preferably, the depth of the groove  45  is at least half the diameter of the cannula supply tube  11 ,  12  and up to  3  times the tube  11 ,  12  diameter, or approximately 0.1–0.6 inches. 
   In the preferred embodiment of the invention, the dowel  40  is are of unitary construction. However, in an alternate embodiment of invention, the dowel  40  may be constructed with two or more modules  41 ,  42 ,  43  that are attached together. This may be accomplished using two disks  41 ,  43  having a first circumference, and attaching the two outer disks  41 ,  43  to the opposing faces of a third disk  42  having a smaller circumference. This creates a modular dowel  40  having a first circumference, with a central circumferential groove  45  having a smaller circumference than the proximal  41  and distal  43  outer portions of the modular dowel  40  as in  FIG. 5 . Preferably, the dowel  40  is constructed using a disk  43  having a first circumference, and attaching the disk  43  to the third disk  42  which has a smaller circumference. This creates a modular dowel  40  having a first circumference, with a circumferential groove  45  on the proximal portion  41  of the dowel  40  having a smaller circumference than distal  43  outer portion of the modular dowel  40  as in  FIG. 6 . 
   Referring to  FIGS. 4 and 5 : In one embodiment of the dowel  40 , the face of the proximal portion  41  of the cylindrical dowel  40  is affixed to one face of a length of hook (or loop) fastener material  80 . The dowel  40  is attached to the back face of the hook or loop material  80 , i.e., the face of the material opposite to the attachment point of the dowel  40  has the hook or loop fasteners thereon. This attachment may be accomplished by gluing, sewing, riveting or like attachment methods. This allows the dowel  40  and attached hook or loop fastener material  80  to be attached to the loop or hook material  81  along the headband  5  or crown  6  of the cap  1 . Alternatively, the dowel  40  may be attached directly to the cap  1  by sewing, gluing, riveting or other attachment methods. 
   Referring now to  FIGS. 4 and 6 : In the preferred embodiment of the dowel  40 , the face of the proximal grooved portion  42  of the cylindrical dowel  40  is affixed to one face of a length of hook (or loop) fastener material  80 . The dowel  40  is attached to the back face of the hook or loop material  80 , i.e., the face of the material opposite to the attachment point of the dowel  40  has the hook or loop fasteners thereon. This attachment may be accomplished by gluing, sewing, riveting or like attachment methods. This allows the dowel  40  and attached hook or loop fastener material  80  to be attached to the loop or hook material  81  along the headband  5  or crown  6  of the cap  1 . Alternatively, the dowel  40  may be attached directly to the cap  1  by sewing, gluing, riveting or other attachment methods. 
   Referring now to  FIGS. 7–8 : An alternate retainer assembly  20  for the supply tubes  11 ,  12  comprises a pair of grooved arc retainers  50  which may similarly be affixed to the material  81  on the headband  5  or crown  6  of the cap  1 . The arced retainers  50  are preferably constructed so as to retain supply tubes  11 ,  12  and a nasal cannula nosepiece  18  therebetween, and to be adjustable as to their location on the headband  5  or crown  6  of the cap  1 . Each arced retainer  50  preferably comprises an arced structure  50  with a groove  54  therein, which is adapted to retain a cannula supply tube  11 ,  12  therein, while maintaining a bend in the tube  11 ,  12 . In the embodiment of the retainer  50  of  FIGS. 6 and 7 , each arced retainer  50  comprises a bent length of material  50 . The retainer  50  may be constructed from wood, plastic, metal, leather, hard rubber, or any material sufficiently rigid to support the supply tubes  11 ,  12  and cannula nosepiece  18  therebetween. To maximize comfort to the wearer and provide a more secure attachment point to the cap  1 , the dowels  50  are preferably constructed of a light and rigid material such as plastic. The thickness of the material is preferably between 0.2 to 0.5 inches to provide a light retainer  50 . The arc preferably has a length and a radius of curvature sufficient to preclude kinking and blocking of a cannula tube  11 ,  12  supported thereby. The length of the arc may vary from between 0.5 inches to up to 3 inches, and the radius of curvature may be as few as 1 inch or as much as 10 inches. In the most preferred embodiment, the length of the arc is approximately 1.5 inches with a radius of curvature of 4 inches. The width of the arced retainer is at least as wide as the diameter of a standard cannula tube and preferably at least twice as wide as the cannula tube diameter, or approximately 0.3–1.0 inches. 
   The arced retainer  50  also has a groove  54  along the top portion of the retainer  50 , preferably centered in the width dimension between the proximal  55  and distal  53  portions of the retainer  50 . The depth of the groove  54  must be sufficient to retain a cannula tube  11 ,  12  therein. More preferably, the depth of the groove  54  is at least half the diameter of the cannula supply tube  11 ,  12  and up to 3 times the tube diameter, or approximately 0.1–0.4 inches. 
   On the central portion of the proximal portion  55  of each arced retainer  50  is a connection point  57  for securing the retainer  50  to one face of a length of hook (or loop) fastener material. The connection point  57  is attached to the back face of the hook or loop material  80 , i.e., the face opposite to the attachment point  57  of the retainer  50  has the hook or loop fasteners thereon. In  FIGS. 6 and 7 , this connection point is shown as a flat disc  57  with a small cantilever  56  that connects at the central portion of the arced retainer  50 . The attachment point  57  however may comprise shapes other than a disc, such as a square, and the cantilever  56  may be eliminated. With the cantilever  56  eliminated, the arced retainer  50  may be connected at more than one point to the disc  57 . The attachment between the arced retainer  50 , cantilever  56 , disk  57  and fastener  80  may be accomplished by gluing, sewing, riveting, snaps or like attachment methods. This allows the retainer  50  and attached hook or loop fastener material  80  to be attached to the loop or hook material  81  along the headband  5  or crown  6  of the cap  1 . Alternatively, the retainer  50 , cantilever  56  or disk attachment point  57  may be affixed directly to the cap  1  by sewing, gluing, riveting or other attachment methods. 
   Referring now to  FIGS. 9–11 : In yet another embodiment of retainer assembly  20  for a cannula nosepiece  18  and supply tubes  11 ,  12 , the retainer  20  comprises a pair of grooved triangular retainers  60  having rounded apexes which may similarly be affixed to the material  81  on the headband  5  or crown  6  of the cap  1 . The rounded triangular retainers  60  are preferably constructed so as to retain supply tubes  11 ,  12  and a nasal cannula nosepiece  18  therebetween, and to be adjustable as to their location on the headband  5  or crown  6  of the cap  1 . Each rounded triangular retainer  60  preferably comprises an arced structure  60  with a groove  64  therein, which is adapted to retain a cannula supply tube  11 ,  12  therein, while maintaining a bend in the tube  11 ,  12 . In the embodiment of the retainer  60  of  FIGS. 9–11 , each rounded triangular retainer  60  comprises a block of material essentially shaped as a triangular prism, with the upward pointed apex being rounded. The retainer  60  may be constructed from wood, plastic, metal, leather, rubber, cardboard, foam rubber, resilient Styrofoam, polystyrene or any material sufficiently rigid to support the supply tubes  11 ,  12  and cannula nosepiece  18  therebetween. To maximize comfort to the wearer and provide a more secure attachment point to the cap  1 , the rounded triangular retainers  60  are preferably constructed of a light and rigid material such as foam rubber, which is not only light, but also simplifies assembly because of the ability to easily fabricate a dowel using a punch. The thickness of the material is preferably between 0.2 to 0.5 inches to provide a light retainer  60 . The rounded apex of the triangular retainer  60  preferably has an arc length and a radius of curvature sufficient to preclude kinking and blocking of a cannula tube  11 ,  12  supported thereby. The arc length may vary from between 0.5 inches to up to 3 inches, and the radius of curvature may be as few as 1 inch or as much as 10 inches. In the most preferred embodiment, the arc length is approximately 1.5 inches with a radius of curvature of 4 inches. The width of the rounded triangular retainer  60  is at least as wide as the diameter of a standard cannula tube  11 ,  12  and preferably at least twice as wide as the cannula tube  11 ,  12  diameter, or approximately 0.3–1.0 inches. 
   The rounded triangular retainer  60  also has a groove  64  along the top portion of the retainer  60 , which is preferably located at the proximal portion of the retainer  60 , but which may be centrally or anywhere along in the width dimension between the proximal  65  and distal  63  portions of the retainer  60 . The depth of the groove  64  must be sufficient to retain a cannula tube  11 ,  12  therein. More preferably, the depth of the groove  64  is at least half the diameter of the cannula supply tube  11 ,  12  and up to 3 times the tube  11 ,  12  diameter, or approximately 0.1–0.4 inches. 
   Referring to  FIGS. 9 and 10 : In one embodiment of the invention, the rounded triangular retainers  60  are of unitary construction. However, in an alternate embodiment of invention, each rounded triangular retainer  60  may be constructed with modules (not shown) that are attached together. This may be accomplished using two rounded triangular portions having a first width, height, and circumference, and attaching the proximal  65  and distal  63  rounded triangular portions to the faces of a third rounded triangular portion  67  having a smaller height and circumference. This creates a modular rounded triangular retainer  60  having a first width, height, and circumference, and having a central groove  64  along the upper sides adjacent the rounded apex, wherein the groove  64  has a smaller height and circumference than the outer portions  65 ,  63  of the modular rounded triangular retainer  60 . 
   Referring to  FIGS. 9 and 11 : In the preferred embodiment of the triangular retainers  60 , the rounded triangular retainers  60  are of unitary construction. However, in an alternate embodiment of invention, each rounded triangular retainer  60  may be constructed with modules (not shown) that are attached together. This may be accomplished using a distal rounded triangular portion having a first width, height, and circumference, and attaching distal  63  rounded triangular portion to the face of a third rounded triangular portion  67  having a smaller height and circumference. This creates a modular rounded triangular retainer  60  having a first distal width, height, and circumference, and having a proximal groove  64  along the upper sides adjacent the rounded apex, wherein the groove  64  has a smaller height and circumference than the outer portion  63  of the modular rounded triangular retainer  60 . 
   On the central part the proximal portion  65  or  67  of each rounded triangular retainer  60  is a connection point  61  for securing the retainer  60  to one face of a length of hook (or loop) fastener material  80 . The connection point  61  is attached to the back face of the hook or loop material  80 , i.e., the face of the material  80  opposite to the attachment point  61  of the retainer  80  has the hook or loop fasteners thereon. In  FIGS. 9 and 10 , this connection point  61  is shown as a flat disc  61  with a small cantilever  66  that connects at the central portion proximal portion  65  of the rounded triangular retainer  60 . The attachment point  61  however may comprise shapes other than a disc, such as a square, and the cantilever  66  may be eliminated. With the cantilever  66  eliminated, the rounded triangular retainer  60  may be connected at more than one point to the disc  61 . The attachment between the rounded triangular retainer  60 , cantilever  66 , disk  61  and fastener  80  may be accomplished by gluing, sewing, riveting, snaps or like attachment methods.  FIG. 11  shows the preferred attachment method between the reatainer  60  and the fastener  80 , wherein the fastener material  80  is attached directly (as by gluing) to the proximal grooved portion  67  of the retainer  60 . This allows the retainer  60  and attached hook or loop fastener material  80  to be attached to the loop or hook material  81  along the headband  5  or crown  6  of the cap  1 . Alternatively, the retainer  60 , cantilever  66  or disk attachment point  61  may be affixed directly to the cap  1  by sewing, gluing, riveting or other attachment methods. 
   Referring now to  FIGS. 2 and 3 : The retainers  40 ,  50  and  60  described herein above are attached to an existing hat, cap, or other headgear  1  having essentially unitary headband  5  and crown portions  6 . The crown portion  6  may have right, left, front and rear portions attached to the corresponding portions of the headband portion  5 . In another embodiment of the invention, the headgear  2  comprises another adjustable types of headgear, having separate attachable headband  5  and crown portions  25 . The headband  5  preferably comprises a length of adjustable material, such as a band cloth material, which may also be elasticized. For example the headband  5  may comprise a polyester and/or cotton cloth band with elastic band(s) woven therein. The headband  5  may also comprise a length of hook or loop fastener material. The headband  5  may be of unitary construction (circular), but preferably has a detachable, adjustable portion  51 ,  52  therein. More specifically, a length of elasticized material may be used having fasteners on opposing ends  51 ,  52  thereof. More specifically, a first end  51  of the band may have hook fasteners on the outside face, and on the opposing end  52  loop fasteners on the inside face, such that the hook and loop fasteners are in mating/engageable relationship. Alternatively, hook and loop fasteners may be used on the opposite ends  51 ,  52 , or opposite faces, or both to provide a wide range of engageability. The headband  5  most preferably comprises a length of loop fastener material, having a portion of hook fastener material affixed to the inside face of one opposing end  51  or  52  thereof for engagement with the opposite end  52  or  51  thereof. Furthermore, other means for engaging the ends  51 ,  52  of the headband  5  to each other may include snaps, buttons, buckles, cord and eyelet, or other types of fasteners. This provides a headband portion  5  that is not only elasticized to fit snugly about the head, but also has fasteners to provide a headband  5  that fits a variety of head sizes. 
   Referring again to  FIG. 3 : The headgear  2  also comprises a crown portion  25  that is engageable with the headband portion  5 . The crown portion  25  comprises crown band  25  made from a length of adjustable material, such as a band cloth material, which further may be elasticized. For example the crown band  25  may comprise a polyester and/or cotton cloth band with elastic band(s) woven therein. The crown band  25  is preferably adjustably engageable with and detachable from the headband portion  5 . More specifically, a length of elasticized material may be used for the crown band  25  having fasteners  36  on opposing ends  26 ,  27  thereof, engageable with complimentary fasteners  32  on some or all of the headband  5 . More specifically, each end  26 ,  27  of the crown band  25  may have hook fasteners  36  on the inside face thereof engageable with loop fasteners  32  on the outside faces of the headband  5 , such that the hook and loop fasteners  36 ,  32  are in mating, engageable relationship. The fasteners  32  on the headband  5  may cover the majority of the outside surface of the headband  5 , or may extend along only the front and sides of the headband  5 , to at least above the portion of the headband  5  to be situated above the ears. This provides a great number of attachment points for the ends  26 ,  27  of the crown band  25  to be adjustably engaged with the headband  5 . 
   Alternatively, the crown band  25  may have loop fasteners  36  thereon, and the headband  5  may have hook fasteners  32  thereon. The hook and loop fasteners  32 ,  36  may be used on the opposite ends, or opposite faces of the crown band  25 , or both to provide a wide range of engageability. Furthermore, other means for engaging the ends  26 ,  27  of the crown band  25  to the headband  5  may include snaps, buttons, buckles, cord and eyelet, or other types of fasteners  36 . This provides a crown band portion  25  that is not only elasticized to fit snugly over the head and prevent slippage of the headband  5 , but also has fasteners  36  to provide a crown band  25  that fits a variety of head sizes. 
   In the preferred embodiment of the invention, the crown band portion  26  is affixed to the headband portion  5  above or in front of the user&#39;s ears. However, in alternate embodiments (not shown), the crown band  25  portion may be aligned parallel to a plane between the user&#39;s ears. Alternatively, the crown band  25  may be affixed and aligned perpendicular to a plane between the user&#39;s ears, or at any angle to the plane that provides a secure attachment and retention of the headgear  2  on the user&#39;s head. 
   Referring now to  FIGS. 2–3  and  FIGS. 4–11 : The headgear  2 , comprising a headband portion  5  and crown band portion  25 ) are adapted for affixing a pair of cannula retainers  20  thereto. Specifically, a pair of cannula retainers  20  of the types  40 ,  50 ,  60  shown in  FIGS. 4–11 , are adapted to be adjustably affixed to the crown portion  25  and/or headband portion  5  of the headgear  2 . In the preferred embodiment of the invention, the crown band  25  is affixed with hook type fasteners  36  to the loop type fasteners  32  on the portion of the headband  5  adjacent the user&#39;s ears. The cannula retainers  20 , (i.e., dowels  40 , arced retainers  50 , or rounded triangular retainers  60 ) each are backed by a length of hook type fasteners  80 . The outside faces of both the crown portion  25  and headband portion  5  have exposed loop type fasteners  37 ,  32  thereon for affixing the hook fasteners  80  of the retainers  20  thereto. Thus, the hook fasteners  80  on the retainers  20  may be affixed to loop fasteners  32 ,  37  on any portion of the headband  5  or the crown band  25 . 
   In yet another alternative embodiment of the invention, the exposed surfaces of the headband  5  and crown band  20  may have hook type fasteners  32 ,  37  thereon, and the cannula retainers  20  may have loop fasteners  80  thereon, for affixing to the hook fasteners  32  of the headband and/or the hook fastener  37  of the crown band  25 . In yet another embodiment, the cannula retainers  20  may be permanently affixed to the outer faces of the ends  26 ,  27  of the crown band  25 , by means of sewing, glue, snaps, grommets, rivets or the like. 
   Thus, the present invention provides a cannula retention apparatus comprising an article of headgear  1 ,  2  having retainers  20  adjustably affixed thereon for retention of cannula supply tubes  11 ,  12 . The retainers  20  have rounded upper surfaces with grooves therein adapted for placement and retention of cannula supply tubes  11 ,  12 . The supply tubes  11 ,  12  may tend from the nasal cannula nosepiece  18  to the front of each retainer  20 , into the groove and then tend downwardly from the back of each retainer  20  to the cannula tube junction  14  below the user&#39;s chin. Alternately, for additional security of retention of the supply tubes  11 ,  12 , the tubes may tend upwardly from the nasal cannula nosepiece  18  to the back portion of the retainers  20 , through the groove in each retainer  20 , and then tend downwardly from the front of each retainer  20  to the cannula tube junction  14  below the user&#39;s chin. This placement of the cannula tubes  11 ,  12  provides a more secure retention because the downward tending portion of the tube  11 ,  12  contacts the upward tending portion of the tube  11 ,  12 , and the friction of their mutual contact prevents the tubes  11 ,  12  from sliding in the grooves. 
   The head gear  1 ,  2  is preferably adjustable to provide a proper fit to the user&#39;s head. The retainers  20  are also preferably adjustable to allow their placement in the most comfortable position with relation to the cannula tubes  11 ,  12  and the user&#39;s ears and face. This prevents the positioning of the tubes  11 ,  12  on the ears and face of the user, which is uncomfortable and is more prone to falling off the user&#39;s face. Additionally, the positioning off the ears and face prevents chaffing and pain, as well as dislocation of the tubes  11 ,  12  and cannula nosepiece  18  due to body movement of the patient, i.e., when walking or during sleep. 
   While the above description contains many specificities, these should not be construed as limitations on the scope of the invention, but rather as exemplification of preferred embodiments thereof. Many other variations are possible, for example: 
   While in the preferred embodiment of the invention the headgear comprises either a cap or an adjustable headband and crownband, many other types of headgear including helmets, western hats, surgical caps, ski hats; hospital caps; golf caps; tennis caps; fishing hats; western hats; men&#39;s and women&#39;s dress hats, derbies; fedoras; bonnets; helmets; construction hard hats; straw hats; visor-less caps; berets; winter hats; and practically any type of headgear may be used; 
   The headgear may be constructed from a variety of materials including cotton, polyester, cotton/poly blends, elasticized material, lycra, silk, felt, leather, plastic, paper, straw and any variety of materials used in making hats; 
   The headgear may comprise a headband and a crown portion, simply a headband, or a headband and one crown band, or multiple crown bands; 
   The retainers may comprise grooved cylinders, arcs, rounded triangles, rounded squares, or a variety of other rounded polygonal prisms with grooves in the rounded upper surfaces thereof; 
   The retainers may be constructed from wood, plastic, metal, leather, rubber, cardboard, foam rubber, polystyrene, resilient Styrofoam or any material sufficiently rigid to support the supply tubes and cannula; 
   The fasteners for the headband, crown band, and/or retainers may comprise snaps, grommets, hook and eye, hook and loop, laces, buckles, glue, rivets, sewing, or any other known means of attachment, either permanent or detachable.