Abstract:
Anxiety attacks can often be limited or eliminated by reducing the concentration of inhaled carbon dioxide. Disclosed is a handheld device for reducing the carbon dioxide concentration of inhaled air by using stacked sheets having rows of adsorbents deposited thereon and which form a removable cartridge. The cartridge is placed into an adsorbent cartridge cradle to secure the cartridge within the device housing and to maintain ventilation channels through the cartridge. Inhaled air passes through the adsorbent containing cartridge and exhaled air exits the device through a bypass to avoid poisoning the adsorbent with exhaled carbon dioxide.

Description:
TECHNICAL FIELD 
       [0001]    The present invention relates to a portable, handheld chemical adsorbent system/device for reducing anxiety and the symptoms of panic attacks through the reduction of inhaled carbon dioxide. 
       BACKGROUND 
       [0002]    Anxiety is a term used generally to describe several disorders whose symptoms include apprehension, fear, and nervousness either as an abnormal response to an environmental condition or sometimes without a precursor stressor. Mild anxiety is vague and unsettling, while severe anxiety can be extremely debilitating, having a serious impact on daily life. 
         [0003]    The cause of this condition is still not understood, but it has been long known that the vulnerability to panic disorder is strongly genetic. The amygdala has a significant role in the experience of both instinctive fear and fear that is learned from life experiences. Studies have shown that that inhaling elevated concentrations of carbon dioxide can generally induce anxiety and trigger panic attacks. Some anxiety and panic reactions are known to require the presence of the acid-sensing protein in the amygdala. An increase in carbon dioxide in the bloodstream reduces blood pH. One of the most consistent research findings about patients suffering from panic disorder is that they are hypersensitive to carbon dioxide levels in the air and other precursors to increased brain acidity. Research indicates that 80% of patients with panic disorder typically experience a panic attack when they inhale air containing 5% CO 2  and that 2 breaths of 50% CO 2  can trigger attacks immediately within this group. Further research has shown that the close relatives of panic prone patients will also panic during carbon dioxide inhalation, despite having been previously asymptomatic for an anxiety disorder. A hypersensitivity to acid in the brain seems to be indicative of a predisposition to panic attacks. Research has shown that CO 2  levels of 600-950 ppm is commonly found in moderately populated enclosed areas (Cox, S, Lawrence, J and Sheehan, D, (1995). Single Ion Gas Chromatographic/Mass Spectroscopic Quantitative Analysis os Environmental CO 2  in Agoraphobic Environments; Anxiety 1; 275-7). 
         [0004]    Generalized Anxiety Disorder, i.e. GAD, is a chronic disorder characterized by excessive, persistent anxiety about nonspecific life events, objects, and situations and GAD is diagnosed when a person worries excessively about a variety of everyday problems for at least 6 months. GAD sufferers often feel afraid and worry about their health, money, family, work, or school, but they have trouble both identifying the specific fear and controlling the worries. Their fear is usually unrealistic or out of proportion with what may be expected in their situation. Sufferers expect failure and disaster to the point that it interferes with daily functions like work, school, social activities, and relationships. 
         [0005]    A panic attack is a sudden episode of intense fear that triggers severe physical reactions when there is no real danger or apparent cause. Panic attacks and anxiety are complex conditions for which little is known about their physiological triggers. It is believed that some individuals possess a hypersensitivity to elevated CO 2  levels that should normally be tolerated by healthy individuals. 
         [0006]    The removal of CO 2  from air typically relies upon a chemical adsorbent to remove the undesired constituent from air and is commonly referred to as CO 2  scrubbing. Porous inorganic metal oxides such as alkali metals or alkali-earth metals providing alkalinity have also been widely incorporated for CO 2  capture. Among the various metal oxides, lithium and calcium based materials are preferred as effective CO 2  adsorbents because of their high adsorption capacity. 
         [0007]    Other methods for CO 2  scrubbing techniques include chemical absorption through alkanolamine-based absorbents, ionic liquid-based absorbents, and blended absorbents. Additional methods incorporate physical adsorbents such as carbonaceous materials, e.g. activated carbon and graphene, zeolite, ordered mesoporous silica, e.g. M41s, SBA-n, and AMS and metal-organic frameworks. Chemical adsorbents include lithium materials, e.g. LiOH and Li 2 O 2 , calcium materials, e.g. Ca(OH) 2 , and amine-based materials. 
       SUMMARY 
       [0008]    The subject device of the present application is a handheld scrubber utilized to remove undesired constituents from air prior to inhalation. The device is primarily utilized to reduce the concentration of CO 2  in inhaled air so as to inhibit the onset of anxiety or to provide a fast-acting intervention during the onset of anxiety or panic attacks among those afflicted with a hypersensitivity to CO 2 . 
         [0009]    A disproportionate tracheal/blood CO 2  ratio may induce a signal to the locus ceruleus-amygdala alarm and fear centers of the brain resulting in anxiety or even panic attacks in persons predisposed to such afflictions. Higher CO 2  levels have also been shown to impair the quality of higher order brain functions in persons without these afflictions. The desire to escape an environment detected to be rich in CO 2  is believed to be a physiological response common in mammals. 
         [0010]    The hypersensitive response to elevated CO 2  levels is rapidly reversible once the CO 2  concentration falls below that required to induce the response. However, it is not always possible to remove a person so afflicted from a confined environment, e.g. a moving car, poorly ventilated work space or classroom, a crowded elevator, or an airplane. Additionally, time may be of the essence and the afflicted person may need to rapidly overcome the effect to focus on the task or decision at hand. 
         [0011]    In order to provide an effective, rapid, and non-pharmacological treatment of symptoms related to the exposure to elevated CO 2  levels, a handheld air scrubber that can be carried in a pocket, briefcase, or purse has been developed which employs a chemical adsorbent to remove substantial quantities of CO 2  from air inhaled through the device until the adsorbent bed contained therein is substantially depleted. Ideally the device possesses valves to direct inhaled air across the adsorbent bed and to provide an alternative channel for exhaled air so as to direct CO 2  rich expirations out of the device without passing back across the adsorbent bed. Other undesired constituents may also be removed from air by selecting the appropriate absorbents and/or adsorbents. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0012]      FIG. 1  depicts a perspective view of a preferred embodiment of the handheld air scrubber. 
           [0013]      FIG. 2  depicts a perspective view of a preferred embodiment of the filter cartridge housing. 
           [0014]      FIG. 3  depicts an exploded perspective view of a preferred embodiment of the handheld air scrubber, filter cartridge housing, and filter cartridge. 
           [0015]      FIG. 4  depicts a cross sectional view of a preferred embodiment of the handheld air scrubber along the proximal-distal (A-A′) axis. 
           [0016]      FIG. 5  depicts a perspective view of the front of a preferred embodiment of the handheld air scrubber. 
           [0017]      FIG. 6  depicts a partial cross sectional perspective view of the rear of a preferred embodiment of the handheld air scrubber depicting the adsorbent cartridge disposed therein. 
           [0018]      FIG. 7  summarizes research results into the effect of elevated CO 2  levels on human decision making. 
           [0019]      FIG. 8  depicts a cross-sectional view of the adsorbent cartridge. 
           [0020]      FIG. 9  depicts a cross-sectional view of a single adsorbent sheet. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0021]    A handheld air scrubber device  100  for short term use is depicted in  FIGS. 1-6  and  8 - 9 . In a preferred embodiment, the handheld air scrubber device  100  possesses a housing  50  comprised of a first lateral casing  40  and a second lateral casing  45  which are joined at the casing joint  47 . 
         [0022]    The present application is directed to the disclosure of a handheld device  100  utilized to remove undesired constituents from ambient air immediately prior to its inhalation. This device is particularly useful in enclosed environments where these undesired constituents, e.g. CO 2  and CO, can accumulate to produce deleterious effects on humans who inhale such contaminants. 
         [0023]    The process of purifying air is commonly known as “scrubbing.” Scrubbing CO 2  from inhaled air is useful to treat the onset of anxiety and panic attacks. Moreover, as is shown in  FIG. 6 , exposure to elevated levels of indoor CO 2  has been shown to impair human decision making. The use of the disclosed device is believed to not only alleviate some symptoms of the onset of anxiety and panic attacks, but is also believed to improve decision making by reducing the concentration of CO 2  in inhaled air. 
         [0024]    A common method for scrubbing is through the use of chemical adsorbents  80  to remove undesired constituents as air comes into contact with a sufficient quantity of that adsorbent  80 . The efficiency of the scrubbing process depends on the duration a given volume of air is in contact with an unsaturated adsorbent  80 , i.e. residence time, the efficiency of the adsorbent  80  itself in removing the undesired constituent irrespective of time, and the rate of removal of the undesired constituent from air when in contact with the adsorbent  80 . 
         [0025]    In a preferred embodiment, as depicted in  FIG. 7 , the handheld air scrubber  100  possesses a ventilation port  5  at the distal end of ventilation port sheath  6  that is placed in the mouth of the user and through which air is inhaled from the housing  50  along the inhalation route  60 , and exhaled through the device  100  along the exhalation route  70 . Inhaled air is drawn into the housing  50  through the inhalation port  17  as the user inhales and creates a vacuum. In a preferred embodiment, a plurality of inhalation ports  17  are utilized at the housing base  43 . The inhaled air enters the air treatment chamber  30  as it passes through the inhalation ports  17  at the housing base  43 . The air treatment chamber  30  houses the air treatment device  88  which acts to scrub undesired constituents from the air. In a preferred embodiment, the air treatment device  100  housed within the air treatment chamber  30  is an adsorbent cartridge  90 . 
         [0026]    The air treatment chamber  30  further possesses a means to secure the adsorbent cartridge  90  in a fixed position within the housing  50 . In a preferred embodiment, the air treatment chamber  30  possesses cartridge ribs  37  extending from the first air treatment chamber wall interior surface  36  of the first air treatment chamber wall  48  and the second air treatment chamber wall interior surface  38  of the second air treatment chamber wall  49  of the lateral casings  40 ,  45  to mechanically hold the cartridge  90  in place in a friction fit arrangement. The air treatment chamber  30  further possesses base cartridge stops  58  extending into the air treatment chamber  30  so as to lift the cartridge  90  off of the inhalation ports  17 . The air treatment chamber  30  further possesses a top cartridge stop  59  extending into the air treatment chamber  30  from the base  43  so as to set an upper limit for the movement of the cartridge  90  within the air treatment chamber  30 . 
         [0027]    The inhaled air is drawn through the inhalation ports  17  and through the cartridge  90  within the air treatment chamber  30 . The air treatment chamber  30  is sealed at the top by a chamber ceiling  32 . An internal inlet port  27  connects the air treatment chamber  30  to the transverse air duct  20  running from the anterior face  42  to the posterior face  46  of the device  100 . An inlet valve  7  opens and closes the internal inlet port  27  by rotating above the inlet valve  7  and up and distally through the transverse air duct  20  about an inlet valve hinge  8  sited at the distal end of the internal inlet port  27 . In a preferred embodiment, the inlet valve  7  is a flapper type valve with dowels  55  which are received into dowel seats  57  within the housing  50 . 
         [0028]    The inlet valve  7  rests on an inlet valve stop  9  which acts to prevent the inlet valve  7  from rotating into the air treatment chamber  30 . At rest the inlet valve  7  seats against and seals the internal inlet port  27 . 
         [0029]    The outlet valve  11  rests on an outlet valve stop  12  which acts to prevent the outlet valve  11  from rotating proximally into the transverse air duct  20  and over the inlet valve  7 . The outlet valve  11  acts to seal the outlet port  25  during inhalation. Sealing the outlet port  25  during inhalation ensures that a sufficient vacuum is created to draw air into the transverse air duct  20  from the air treatment chamber  30  and open the inlet valve  7 . 
         [0030]    In a preferred embodiment, the outlet valve  11  is a flapper type valve  53  with dowels  55  which are received into dowel seats  57  within the housing  50 . At rest, the outlet valve  11  seats against the outlet port  25  within the transverse air duct  20  and prevents air from being inhaled through the exhaust port, bypassing the adsorbent cartridge  90 . 
         [0031]    During exhalation, this seals the air treatment chamber  30  and directs exhaled air through the transverse air duct  20  and against the outlet valve  11 . The pressure of the exhaled air forces the outlet valve  11  open and allows exhaled air to exit the housing  50  through the exhaust port  13 . Exhaled air is prevented from entering the air treatment chamber  30  and traversing the adsorbent cartridge  90  to avoid premature depletion of the adsorbent  80  by unnecessary exposure to constituents of the exhaled air. 
         [0032]    In a preferred embodiment, the inlet valve  7  and outlet valve  11  are flapper type valves which rotate about hinges  15  at the base of each valve  7 ,  11 . At rest, the inlet valve  7  lies closed against the top of the air treatment chamber  30  so as to seal the internal inlet port  27 . 
         [0033]    During inhalation, the inlet valve  7  opens due to the vacuum within the transverse air duct  20  and permits air to flow from the inhalation ports  17  across the cartridge  90  in the air treatment chamber  30 , through the inlet valve  7 , and into the transverse air duct  20 . The vacuum also acts to close the outlet valve  11  which seals the outlet port  25 . Inhaled air follows the inhalation path  60  and exits the ventilation port  5  into the mouth of the user via the ventilation port sheath  6 . 
         [0034]    During exhalation, air is forced into the housing through the ventilation port  5 , across the transverse air duct  20 , against the outlet valve  11  which is hingedly attached at the top of the exhaust port  13  in the transverse air duct  20 . The force of the air exhaled into the housing  50  via the ventilation port  5  forces the inlet valve  7  to close and opens the outlet valve  11 . After passing through the outlet port  25 , the exhaled air exits through the exhaust port  13  at the distal end of the transverse air duct  20 . 
         [0035]    The housing  50  is preferably constructed of a rigid material such as a plastic to protect the integrity of the adsorbent sheets. The inlet valve  7  and outlet valve  11  are likewise constructed of a rigid material. The housing  50  is preferably molded into two lateral casings  40 ,  45  which are joined about a casing joint  47 . 
         [0036]    As depicted in  FIGS. 7-8 , the adsorbent  80  is preferably retained on a planar adsorbent support  31 . Dustless preparations of commercially available adsorbents are preferred so as to avoid issues with the inhalation of adsorbent  80 . Dustless adsorbents  80  are especially preferred when alkali metals and alkali earth metals containing adsorbents  80  are utilized due to the potential for chemical burns or when toxic adsorbents  80  are employed. In a preferred embodiment, the adsorbent support  31  is constructed of a card stock or other sufficiently rigid cellulosic or similar material with sufficient rigidity to maintain its form but pliable so as to permit the cartridge ribs  37  in the air treatment chamber  30  to deform and hold the edges of the filter cartridge housing  99 . 
         [0037]    In a further preferred embodiment, the adsorbent  80  is retained on each support  31  in parallel vertical rows  85  across one face of the support  31 . When stacked together, these supports  31  are arranged so that the adsorbent rows  85  on each support  31  lie adjacent to the planar surface of an adjacent support  31 . This arrangement, when supports  31  are tightly stacked together to form an adsorbent cartridge  90 , uses the empty rows created from the open spaces between adsorbent rows  85  as adsorbent cartridge ventilation channels  83  through which air is inhaled and contacts the adsorbent  80  for the removal of CO 2  or other contaminants. Ideally, there is sufficient volume in the cartridge ventilation channels  83  to minimize the pressure differential across the cartridge  90 . 
         [0038]    The thickness of the adsorbent cartridge  90  is optimized to ensure a tight fit within the air treatment chamber  30  so as to ensure sufficient air flow through the adsorbent cartridge  90  rather than around the adsorbent cartridge  90 . Ideally the supports  31  are bound together to fix each sheet&#39;s relative position within the adsorbent cartridge  90 . The air treatment chamber  30  utilizes top cartridge stops  59  to ensure that a head space is preserved by preventing the adsorbent cartridge  90  from moving up toward the internal inlet port  27 . The air treatment chamber  30  also possesses base cartridge stops  58  to ensure that some space is maintained between the bottom of the adsorbent cartridge  90  and the air treatment chamber floor  35 . 
         [0039]    The air treatment chamber floor  35  possesses a plurality of inhalation ports  17  through which air enters the housing  50  during inhalation. Some space between the bottom of the adsorbent cartridge  90  and the inhalation ports  17  assists in inhibiting foreign objects from contacting the adsorbent supports and adsorbent rows in a way that could potentially dislodge some adsorbent  80  from the supports  31 . 
         [0040]    The adsorbent cartridge housing  99 , i.e. filter cartridge cradle  99 , retains the filter cartridge  90 , i.e. adsorbent cartridge  90 . The adsorbent cartridge housing  90  possesses a substantially rectangular support floor  96  from which support stops  95  extend vertically from each corner on the proximal side of said support floor  96  along with side cartridge guides  93  and end cartridge guides  97  which serves to retain and position the adsorbent  36   
         [0041]    cartridge  90 . It is important to keep the absorbent sheets  91  properly aligned to keep the filter ventilation channels  83  open and unobstructed and to minimize the pressure differential (AP) across the cartridge  90 . When properly positioned, the ventilation channels  83  minimize the pressure differential by keeping all or most of the channels  83  open and contiguous across the cartridge  90 . While it is important to keep the sheets  91  properly aligned along their edges, it is also important to prevent them from moving along the proximal-distal axis, i.e. up-and-down within the cartridge cradle  99  as they could shift and cause channels  83  to be blocked. 
         [0042]    The distal side of said support floor  96  possesses at least one tab  94  extending vertically down and away from said support floor  96  to contact the air treatment chamber first side wall  49  on one side of the air treatment chamber  30  which acts to tension the filter cartridge cradle  99  and filter cartridge  90  against a second air treatment chamber wall  48 . The tab  94  contacts the first side wall  49  between the tab positioning ridges  39  which serve to hold the filter cartridge cradle  99  in place. 
         [0043]    It is anticipated that the device  100  will be disposable, with the housing  50  being supplied pre-loaded with an adsorbent cartridge  90 . The device  100  is further anticipated to be sold in sealed packaging. The packaging could be vacuum sealed or possess an inert atmosphere such as N 2 . 
         [0044]    While the present invention may have been disclosed herein with reference to certain embodiments, it will be apparent that modifications and variations are possible without departing from the spirit and scope of the invention as defined herein. Furthermore, it should be appreciated that any and all examples in the present disclosure, while illustrating embodiments of the invention, are provided as non-limiting examples and are, therefore, not to be taken as limiting the various aspects so illustrated. The present invention is intended to have its full scope consistent with the drawings and description herein, and equivalents thereof. Accordingly, the drawings and detailed description are to be regarded as illustrative and not as restrictive.