Patent Application
20080066739
Many aspects of the present disclosure can be better understood with reference to the following drawings. The components in the drawings are not necessarily to scale, emphasis instead being placed upon clearly illustrating the principles of the present disclosure. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the several views.
Before the present disclosure is described in greater detail, it is to be understood that this disclosure is not limited to particular embodiments described, and as such may, of course, vary. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only, and is not intended to be limiting, since the scope of the present disclosure will be limited only by the appended claims.
Where a range of values is provided, it is understood that each intervening value, to the tenth of the unit of the lower limit unless the context clearly dictates otherwise, between the upper and lower limit of that range and any other stated or intervening value in that stated range, is encompassed within the disclosure. The upper and lower limits of these smaller ranges may independently be included in the smaller ranges and are also encompassed within the disclosure, subject to any specifically excluded limit in the stated range. Where the stated range includes one or both of the limits, ranges excluding either or both of those included limits are also included in the disclosure.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. Although any methods and materials similar or equivalent to those described herein can also be used in the practice or testing of the present disclosure, the preferred methods and materials are now described.
All publications and patents cited in this specification are herein incorporated by reference as if each individual publication or patent were specifically and individually indicated to be incorporated by reference and are incorporated herein by reference to disclose and describe the methods and/or materials in connection with which the publications are cited. The citation of any publication is for its disclosure prior to the filing date and should not be construed as an admission that the present disclosure is not entitled to antedate such publication by virtue of prior disclosure. Further, the dates of publication provided could be different from the actual publication dates that may need to be independently confirmed.
As will be apparent to those of skill in the art upon reading this disclosure, each of the individual embodiments described and illustrated herein has discrete components and features which may be readily separated from or combined with the features of any of the other several embodiments without departing from the scope or spirit of the present disclosure. Any recited method can be carried out in the order of events recited or in any other order that is logically possible.
The following examples are put forth so as to provide those of ordinary skill in the art with a complete disclosure and description of how to perform the methods and use the compositions and compounds disclosed and claimed herein. Efforts have been made to ensure accuracy with respect to numbers (e.g., amounts, temperature, etc.), but some errors and deviations should be accounted for. Unless indicated otherwise, parts are parts by weight, temperature is in ° C., and pressure is at or near atmospheric. Standard temperature and pressure are defined as 20° C. and 1 atmosphere.
Embodiments of the present disclosure will employ, unless otherwise indicated, techniques of synthetic organic chemistry, biochemistry, pharmacology, medicine, and the like, which are within the skill of the art. Such techniques are explained fully in the literature.
It must be noted that, as used in the specification and the appended claims, the singular forms “a,” “an,” and “the” include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to “a support” includes a plurality of supports. In this specification and in the claims that follow, reference will be made to a number of terms that shall be defined to have the following meanings unless a contrary intention is apparent.
Prior to describing the various embodiments, the following definitions are provided and should be used unless otherwise indicated.
As used herein the term “aerosol” refers to a suspension of solid or liquid particles in a gas.
As used herein the term “genetic material” generally refers to material that includes a biologically active component, including but not limited to nucleic acids (e.g., single or double stranded DNA or RNA or siRNA's), proteins, peptides, polypeptides, and the like.
As used herein the term “surfactant” or “pulmonary surfactant” generally refers to specific lipo-protein substances naturally produced in the lungs that are essential for proper breathing, alveolar stability and gas exchange. Pulmonary surfactants are surface-active agents naturally formed by type 11 alveolar cells that reduce the surface tension at the air-liquid interface of alveoli. Pulmonary surfactants are generally made up of about 90% lipids (about half of which is the phospholipid dipalmitoylphosphatidylcholine (DPPC)) and about 10% protein. At least four native surfactants have been identified: SP-A, B, C, and D. The hydrophobic surfactant proteins B (SP-B) and C(SP-C) are tightly bound to the phospholipids, and promote their adsorption into the air-liquid interface of the alveoli. These proteins are critical for formation of the surfactant film. The term “surfactant” also includes currently available surfactant preparations, including, but not limited to, Survanta® (beractant), Infasurf® (calfactant), Exosurf neonatal® (colfosceril palmitate), Curosurf® (poractant alfa), Surfaxin® (lucinactant), Aerosurf® (aerosolized Surfaxin®), Vanticute® (lusupultide), Alveofact® (bovactant), as well as preparations being developed.
As used herein, the term “purified air” refers to air that has been synthesized from pure gasses or environmental air that has been filtered to reduce the amount of particulate matter and/or other contaminants such as, but not limited to, ozone, SO2, and NO2. While such contaminants may not be entirely removed/eliminated, the amount may be reduced from the amount found in the air of a particular environment and preferably reduced from the amount in air filtered with the use of HEPA grade filters. In some preferred embodiments, purified air includes less than about 0.03% of particulate matter having a particle size greater than about 20 nm, as compared to the amount of particulate matter in the environmental air being purified. In some preferred embodiments the purified air includes less than about 0.0001% of the particle count of the environmental air being purified. In embodiments, purified air includes a reduced amount of ozone, as compared to the environmental air being purified. In some embodiments, purified air includes a reduced amount of SO2, as compared to the environmental air being purified, and in some embodiments includes a reduced amount of NO2 as compared to the environmental air being purified. In some preferred embodiments, the purified air has a reduced amount of ozone, a reduced amount of SO2, and/or a reduced amount of NO2, and a particle count less than about 0.03% than the particle counts of the environmental air being purified.
As used herein, the term “positive pressure” refers to a pressure of the air being supplied to the patient being greater than the atmospheric pressure.
As used herein, the terms “user”, “host”, and/or “patient” include humans and other living species that are in need of treatment and capable of being ventilated or of using the disclosed respirator. In particular, the terms “user”, “host” and/or “patient” includes humans and mammals (e.g., cats, dogs, horses, chicken, pigs, hogs, cows, and other cattle).
As used herein the term “pharmaceutical drug” generally refers to any pharmaceutically effective compound used in the treatment of any disease or condition. For example, the pharmaceutical drug can be used in the treatment of diseases such as asthma, bronchitis, emphysema, lung infection, cystic fibrosis, AAT deficiency, COPD, ARDS, IRDS, BPD, and MAS, among many other conditions. Useful pharmaceutical drugs that can be delivered via inhalation according to the disclosed methods include, but are not limited to, those that are listed within the Physician's Desk Reference (most recent edition, e.g., 2007), published by Thomson PDR. Such drugs include, but are not limited to those set forth hereinafter in Table 1, which drugs can be administered with the disclosed device for the correlated indication. Table 1 provides a list of exemplary drugs that can be delivered via the instantly-disclosed device, all of which have been approved by the U.S. Food and Drug Administration for pulmonary delivery. Other drugs may be used in the presently disclosed methods, and the following list is not intended to be exhaustive.
P. aeruginosa.
In addition to the above-listed drugs already FDA approved for pulmonary delivery, other drugs referenced for possible pulmonary delivery by the disclosed methods include, but are not limited to, those provided in Table 2 below.
Multiple drugs listed above are currently undergoing research for delivery to the pulmonary tree. The following discussion provides specific examples, but is not intended to be all inclusive of the rapidly advancing field of research regarding pulmonary delivery of pharmaceuticals. The medical port device and delivery method of the present disclosure is intended to deliver any currently existing and future developed drugs that are currently or become approved for pulmonary delivery as they become available for clinical use.
Research has established that peptides, polypeptides, and proteins are an effective way to deliver medications to the rest of the body via the pulmonary route. Additionally many peptides, polypeptides, and proteins also act themselves as therapeutic agents for the treatment of various conditions. For example, multiple proteins are currently undergoing research to alter metabolism. Over 60% of the U.S. population is considered obese. Obestatin, polypeptide YY and leptin are appetite-suppresing hormones. Ghrelin is an appetite boosting hormone. Rimonabant is a new medication which may be a possible new treatment for obesity. Cannabinoid-1 receptor antagonist SR141716A and opioid antagonist LY255582 are other medications that suppress the appetite. Other hormones, including insulin preparations, have been studied, and Exubera has recently become available in a form suitable for inhalation. Calcitonin is inhalable and can treat osteoperosis, hypercalcemia, and Paget's disease. FSH is a hormone that can treat infertility. Growth hormone can treat growth retardation. TSH can treat hypothyrodism, which can cause fatigue and weight gain. Other hormones undergoing research as inhaled forms include somatostatin and parathyroid hormone. LHRH (luteinizing hormone-releasing hormone), including both agonist and antagonist inhalable forms, are being studied for osteoperosis. An inhaled phosphodiesterase-5 inhibitor for erectile dysfunction is also being studied. Vassopressin analogue is used to treat a number of cardiovascular conditions. Immunoglobulins are used to treat infections, and may in the future be customized and delivered to the patient to treat particular diseases or disorders. These all represent promising protein/peptide-based treatments for various diseases and conditions, and, based on preliminary research, the inhalational route may be the only, or most effective means of delivering these drugs.
The disclosed methods of administering drugs also include the delivery of other forms of genetic material (e.g., DNA and RNA) for treating various conditions such as treatment of the lung lining for persons suffering from cystic fibrosis, similar to stem cell treatments for Parkinsons disease (e.g., affecting brain stem), and diabetes (e.g., affecting Islets of Langerhorn). Another drug including genetic material is dornase alpha, marketed under the trademark Pulmozyme™, recombinant DNAse, rhDNase, which is an enzyme used for cystic fibrosis, etc., to reduce the incidence of infection by hydrolyzing DNA in sputum viscoelasticity. An inhalation form of Interleukin I is being studied for asthma. Interferon therapy is undergoing research for multiple sclerosis and Hepatitis B and C. Survivin gene therapy for pulmonary arterial hypertension and hA1PI (human alpha-1 protease inhibitor) or in-situ gene therapy to reduce certain types of emphysema are also being studied. Gene therapy for cancer treatment or prevention is also being studied. Examples include aerosol gene therapy with replacement of p53 genes for lung cancer, and treatment with inhaled cytotoxic drugs (chemotherapy) for lung cancer.
Exemplary proteins for delivery according to the methods of the present disclosure can be found in the database maintained by UniProt Consortium at the following database http://www.pir.uniprot.org/ (Jan. 26, 2006), which is hereby incorporated by reference in its entirety. Exemplary polynucleotides for delivery for gene therapy and/or other treatment applications can be found at the following databases: http://www.ebi.ac.uk/embl/index.html ((Jan. 26, 2006) (RNA/DNA sequences) (the EMBL Nucleotide Sequence Database, also known as EMBL-Bank, is maintained by the maintained by the European Bioinformatics Institute (EBI) and produced in collaboration by GenBanK (USA) and the DNA Database of Japan (DDJP)) and http://imgt.cines.fr/IMGT_GENE-DB/GENElect?livret=0 (Jan. 26, 2006) (Immunoglobulin and T cell receptor genes) (maintained by the International ImMunoGeneTics Information System®), both of which are hereby incorporated by reference in their entireties. Lipids may also be delivered via the pulmonary route via methods of the present disclosure; exemplary lipids can be found at the following database: http://www.lipidmaps.org/data/structure/index.html (Jan. 26, 2006), maintained by the Lipid Metabolites and Pathways Strategy (LIPID MAPS), which is hereby incorporated by reference herein in its entirety.
Inhaled gases are another class of medications that can be delivered via the systems and methods of the present disclosure. Nitrous Oxide is often used as an anaesthetic. Heliox is used in patients undergoing respiratory distress.
Multiple antibiotics are being studied for inhalation. As noted above, tobramycin has been approved for inhalation. Penicillin, quinolones (Cipro), aztreonam, and other antibiotics for pulmonary and systemic infections have been evaluated. Immunoglobins (antibodies) in an inhaled form are also undergoing evaluation in infections and/or inflammatory states. Recombinant human granulocyte colony stimulating factor (GCSF) strengthens the immune system, and an inhaled form is available.
Central nervous system (CNS) applications of inhaled drugs are also being researched. Nicotine is available in several forms but the present application of the medical port and delivery method proposes benefits and alternatives to tobacco addiction without exposure to the carcinogens of the tobacco products. Inhaled drugs that treat migraine headaches and inhaled narcotics, such as morphine, for treatment of acute or chronic pain are also available. Other CNS drugs undergoing research include entonox (inhaled sedative that is a combination of nitrous oxide and oxygen) and inhaled anxiolytics.
Other novel and diverse drugs can also be delivered to the pulmonary tree. Cyclosporin A (organ transplant rejection medicine) has recently been reported to be advantageous in an inhaled form. Alpha-1 antitrypsin enzyme therapy is being studied for treatment of emphysema and cystic fibrosis. Delivery of saltwater solution two times as salty as the Atlantic Ocean has been beneficial in an inhaled form in cystic fibrosis patients. Some other drugs or medications that have been identified as good candidates for use with the disclosed device are inhaled gases and sedatives/anesthetics like nitrous oxide for pulmonary hypertension or for pain. Desflurane and all the “anes” family of anesthetics are also potential candidates. For instance, Corus Pharma of Seattle Wash. is currently investigating inhaled lidocaine for alleviating chronic cough for cancer or chronic emphyzema. Other drugs include anxiolytics such as midazolam, marketed under the trademark Versed™ for reducing anxiety (nasal Versed for children or adults is currently available), zolmitriptan, marketed under the trademark Zomig™, and sumatriptan, marketed under the trademark Imitrex™ (which are currently available as nasal sprays for migraines); and antibiotics such as tobramycin solution, which is currently discussed in literature and is already inhalable for cystic fibrosis and bronchial infections, and vancomycin, which is not yet inhaled. Inhaled steroid drugs such as Pulmicort™ are also currently available and are a good candidate for delivery via inhalation.
Drugs that are currently delivered in suppository format and thus rely on mucous membrane absorption represent another class of drugs that may be appropriate for delivery by the presently disclosed system. A non-limiting example of such a suppository-based drug is promethazine, marketed under the trademark Phenergan™, for dizziness and nausea, which is also available orally.
Other pulmonary drugs currently known and that can be used with the disclosed device include, but are not limited to, inhaled prostaglandins such as for newborns to correct patent ductus arteriosis (which closes the bypass hole in the heart); nitrolingual (a nitrogylcerin) pumpspray, which is FDA-approved (lingual spray) for treating coronary artery disease such as angina; and inhaled antihistamines such as azelastine, marketed under the trademark Astelin™, and DDAVP nasal spray, which acts as an antidiuretic by having an effect on the kidneys.
As noted above, some drugs are not currently available for pulmonary administration but are likely candidates for delivery via patient inhalation. These include, for example, inhaled arthritis treatments and vaccines, such as an influenza nasal vaccine (for example that marketed under the trademark Flumist™, which is currently delivered by syringe as a flu vaccine) and TB vaccines.
Drugs for reducing flu symptoms, such as Virazole™, which is available in aerosol form for fighting the effects of Respiratory Syncytial Virus (RSV), are also of particular interest. The presently disclosed systems and methods take advantage of such drugs that are currently available for pulmonary delivery by providing different degrees of dealing with flu virus such as avian flu virus. In the first instance, the disclosed device provides a comfortable, filter system for filtering out pathogens. Secondly, it can be used in conjunction with the medi port of the disclosed device to deliver ribavirin for inhalation, USP, marketed under the trademark Virazole™, or another suitable drug. Thirdly, it can be used in conjunction with devices (such as described in U.S. patent application Ser. No. 11/412,231, which is hereby incorporated by reference in its entirety) in which ultraviolet light is used to destroy the DNA, RNA, or pathogens that enter the air stream in spite of the filtering system.
The term “pharmaceutical drug” as used herein is also intended to encompass the free acids, free bases, salts, amines, and various hydrate forms including semi-hydrate forms of the drugs mentioned above, as well as pharmaceutically acceptable formulations of such drugs that are formulated in combination with pharmaceutically acceptable excipient materials generally known to those skilled in the art, preferably without other additives such as preservatives. In some embodiments, the drug formulations do not include additional components such as preservatives, which may cause adverse effects. Thus, such formulations consist essentially of a pharmaceutically active drug and a pharmaceutically acceptable carrier (e.g., water and/or ethanol). However, if a drug is liquid without an excipient, the formulation may consist essentially of the drug, which has a sufficiently low viscosity that it can be aerosolized using a respirator device of the present disclosure. In other embodiments, drug formulations may include one or more active ingredients, a pharmaceutically acceptable carrier and/or excipient, as well as other compounds such as, but not limited to, emulsifiers, buffers, preservatives, and the like, as appropriate.
As used herein the term “formulation” generally refers to any mixture, solution, suspension or the like that contains an active ingredient and a carrier and has physical properties such that when the formulation is moved through the respirator device as described herein, the formulation is in a form that is delivered/inhaled/blown by positive pressure into the lungs of a patient. The active ingredient may be any pharmaceutically active drug (as defined above), or diagnostic or imaging agent. The carrier may be any pharmaceutically acceptable flowable agent that is compatible for delivery with the active agent. Useful drugs include drugs defined above, systemically-active drugs delivered to the airways, and useful diagnostics including those used in connection with ventilation imaging. The formulation may also comprise genetic material dispersed or dissolved in a carrier, where the genetic material (when in a cell of the patient) expresses a pharmaceutically active protein or peptide. Formulations may be, for example, solutions, e.g., aqueous solutions, ethanoic solutions, aqueous/ethanoic solutions, saline solutions, colloidal suspensions and microcrystalline suspensions. In embodiments, formulations can be solutions or suspensions of drug in a low boiling point or high vapor pressure propellant. In some embodiments, the formulations can be in solid form. Solid form preparations include powders, tablets, dispersable granules, and capsules. Solid form preparations will be vaporized or aerosolized by the disclosed respirator device, as described hereinafter, so as to be inhaled by a host or patient. Pharmaceutically acceptable excipients can be volatile or nonvolatile. Volatile excipients, when heated, are concurrently volatilized, aerosolized and inhaled with the pharmaceutical drug. Classes of such excipients are known in the art and include, without limitation, gaseous, supercritical fluid, liquid and solids. The following is a list of exemplary carriers within the classes: water; terpenes, such as menthol; alcohols, such as ethanol, propylene glycol, glycerol and other similar alcohols; dimethylformamide; dimethylacetamide; wax; supercritical carbon dioxide; dry ice; and mixtures thereof.
Multiple drugs, drug classes, and evolving therapies (inhaled proteins, genetic material, gases) are being developed to use the inhalation route (nasal, tracheobronchial and alveolar areas). The medical port device disclosed herein and method of delivery is applicable to FDA approved drugs, drugs undergoing current development and any future medications or drugs that can be delivered pulmonically (or via inhalation).
The above drugs and formulations are referenced as being currently or potentially delivered by inhalation or utilized by the respiratory or pulmonary system. It will be appreciated that delivery to nasal passageways and nasal membranes is also within the scope of the present disclosure, and the above drugs and formulations discussed are subject to delivery by the nasal route as well.
While the term medication or drugs is used in the present disclosure, these terms are used widely to include any substance that may have some beneficial or treatment purpose, including amongst other things, substances like water vapor, saline solutions, or compounds used to enhance imaging.
The present disclosure provides systems and methods of delivery of medications to the respiratory system of patients who are capable of unassisted breathing by delivering the medications at a positive pressure relative to atmospheric pressure. In embodiments, the medications are delivered at positive pressure in a stream of air, purified air, or a mixture of gases. In embodiments, the present disclosure provides a system and apparatus for inhaled delivery of medications using purified air at a positive pressure. A device that can deliver the inhaled medications in precise doses and that can deliver medications continuously or in time coordinated response to the respiratory cycles of patients or wearers is also provided. Disclosed herein are devices and systems configured to effortlessly deliver pharmaceutical preparations in purified air to lung air spaces of a patient in a highly efficient, controlled, and targeted manner.
The present disclosure provides a breathing apparatus that serves as a vehicle to administer medication to the user. The present disclosure also provides methods and systems for administering a whole host of drugs via inhalation by a patient, including drugs not previously administered via inhalation.
In embodiments of the system and methods of the present disclosure, the device delivers medications to patients where the patient is capable of breathing without external assistance, and thus invasive breathing assistance or intervention in the recipient's own breathing cycle is not required. This is in contrast to mechanical ventilators, which constitute invasive assisted breathing. As a less extreme example, continuous positive airway pressure (CPAP) machines, designed for treating conditions such as sleep apnea, must intervene to correct the patient's breathing pattern whenever breathing difficulties are experienced, thus also constituting assisted breathing. Another example of assisted breathing includes forms of non-invasive ventilation (NIV) which is used for patients with serious respiratory conditions and those experiencing difficulty breathing without assistance, and is generally used as a last step before intubation. The device of the present disclosure, while not requiring additional respiratory effort on the part of the patient, and while providing some assistance to the user by virtue of positive pressure, does not constitute a device for invasive assisted breathing or intervention into the patient's respiratory cycle.
As used herein, “invasive assisted breathing” refers to breathing assistance requiring intervention in the patient's breathing mechanisms, such as by intubation (for full breathing assistance) or correction of irregular breathing patterns, or for use by patients unable to breath adequately on their own. Although not as invasive as intubation, both CPAP and NIV fall within the class of invasive assisted breathing, as used in the present disclosure. As such, invasive assisted breathing methods and devices typically employ higher pressures than the devices and methods of the present disclosure.
On the other hand, “unassisted breathing” as used herein refers to the ability to breath adequately (e.g., has blood oxygen levels within the normal range) without external assistance such as that provided by one of the above discussed “invasive assisted breathing” methods or devices. In embodiments, the device and methods of the present disclosure are use for patients capable of unassisted breathing. Thus, typically, the pressures employed in the present devices and methods will be lower or otherwise less invasive than those required for devices used for invasive assisted breathing, such as a ventilator or a NIV or CPAP machine. In embodiments, the drug is supplied in air, purified air, or a mixture of gases at a pressure of about 1 cm H2O to about 30 cm H2O. Typically, the pressures employed in the device of the present invention are low enough that the patient's own breathing pattern (e.g. initiation of inhalation and exhalation) is discernable over the machine supplied pressure.
Although the devices and methods of the present disclosure are for use with spontaneously breathing patients who do not require breathing assistance, in some embodiments the device and methods of the present disclosure can be used in combination with a respirator to deliver medications to a ventilated patient. For instance, the present disclosure also includes the use of respirators described in U.S. patent application Ser. No. 11/533,529 entitled “Respirators for Delivering Clean Air to an Individual User” (which is hereby incorporated by reference herein) in conjunction with the apparatus disclosed herein. The systems and methods of the present disclosure make full, safe, and efficient use of the highly absorptive linings of the lungs as a way to administer a large host of medications.
The drug delivery methods of the present disclosure can also be implemented using existing breathing systems. A large number of air supply masks ranging from masks covering the mouth and nose, to full face masks, to mouth nozzles as in SCUBA gear already exist could be implemented with the disclosed drug delivery methods in embodiments.
In some embodiments, the supply of pure air can be synthesized (as opposed to filtering environmental air), such as by mixing the gases from reservoirs of liquid oxygen, liquid nitrogen, and liquid carbon dioxide. In particular, an embodiment provides a system includes an air mover, e.g., a pump or blower or a system, that provides air under pressure, as in a SCUBA tank, to generate an air stream of clean air. Numerous active respirators are known, e.g., the Positive Air Pressure Respirator (PAPR), manufactured by 3M; the Continuous Positive Airway Pressure (CPAP) system, manufactured by several medical suppliers such as Puritan Bennet and Respironics, which includes a pressurized mask that typically covers the nose for addressing sleep apnea; fire-fighter type face masks connected to chemical air filtration systems; and face masks connected to compressed air cylinders such as SCUBA gear for underwater diving. As discussed above, in some embodiments the presently disclosed drug delivery apparatus can be implemented using such prior art devices. However, with the exception of highly purified air in a pressurized tank, the existing air supply masks do not typically provide highly purified air, down to 20 nanometers, in combination with ozone removal, which means that in certain environments drug chemistry could be effected by the pollutants in the air. Therefore, in some preferred embodiments the methods and systems of the present disclosure use respirators described in U.S. patent application Ser. No. 11/533,529, incorporated above.
While the elimination of pollutants from the air can itself be considered a benefit to the user from the standpoint that environmental irritants of the lungs and other organs are eliminated, a closer examination of the composition of typical outdoor air, and particularly indoor air, reveals that purified air is particular important for ensuring effective and safe drug delivery via the pulmonary route. The importance of purified air for the systems and methods of the present disclosure arises based on the high concentrations and chemical composition of the particles normally found in environmental air. While particle counts vary widely depending on the particular setting, indoor room air may easily contain greater than 10 billion particles per cubic meter, with many of those particles having diameters down to the 20 nm range. Moreover, while there is a tendency to think of these particles as being inert objects, a large percentage of these particles are condensed droplets or micro-crystalline particles of organic and inorganic compounds, including such compounds as aromatic hydrocarbons and carbon particulates.
Predicting the chemical composition of pollutants in room air is further complicated by the presence of ozone. While ozone is a harmful pollutant in it's own right, it is also highly reactive. The reaction of ozone with other organically based pollutants results in numerous derivative compounds which have been studied in some detail for outdoor air (the mechanisms of smog creation, etc.) but are not well documented in current literature and are not widely understood in indoor environments. Other organics are also found in indoor air as a result of outgassing by polymers (carpet, upholstery, etc.) or simply as a result of the use of cleaning compounds. One class of organics that have proven particularly active in forming derivative compounds in air when exposed to ozone are terpenes, which are used in many cleaners and air fresheners and which are responsible for the fresh pine or lemon scent of many cleaning products. Terpenes are sometimes employed as a carrier substance for pharmaceuticals (menthol is an example).
Additionally, at a macro scale in solid, or perhaps liquid form, many of these chemical reactions would proceed relatively slowly. But, as is often demonstrated in high school and college chemistry labs, a high surface area to volume ratio increases the reaction rate between two compounds. With many aerosolized pollutant particles in the 20 nm range, the particles have a very large surface area to volume ratio resulting in rapidly occurring reactions.
An area of particular concern regarding the risk of undesirable chemical reactions between therapeutic drugs and environmental contaminants is the pulmonary delivery of proteins and peptides including gene therapy. As described in the review article by F. J. Kelly and I. S. Mudway entitled “Protein Oxidation at the Air-Lung Interface,” Amino Acids (2003) (hereby incorporated by reference in its entirety) certain undesirable reactions are known to occur between proteins and reactive oxygen or nitrogen species such as ozone or nitrogen dioxide. As explained in greater detail in the article, reactive oxygen and nitrogen species and their secondary lipid and sugar oxidation products may interact with proteins causing reactions such as oxidation of the polypeptide backbone of the protein, peptide bond cleavage, protein-protein crosslinking, and a range of amino-acid side chain modifications. Both aromatic amino acids (e.g., tyrosine, tryptophan, phenylalanine) and aliphatic amino acids (e.g., arginine, lysine, proline, and histidine) may be targets of reactive oxygen and/or nitrogen species, cysteine and methionine, the two sulphur-containing amino acids, appear especially sensitive to oxidation.
The combination of organic and inorganic pollutants with reactive chemistries, high particle counts, the presence of ozone, and uncertain derivatives as the result of ozone's interaction with other compounds make it difficult to predict air chemistry. Due to the possible formation of numerous compounds that would negatively impact the effectiveness of the drug itself, or perhaps result in the creation of compounds that are detrimental to health, introduction of pharmaceuticals into air that has not been adequately purified greatly increases the likelihood of negative effects. Hence, purified air is preferred for the delivery methods of the present disclosure.
With particle counts in environmental air at times measuring in excess of 10 billion per cubic meter in urban areas and with particle sizes down to 20 nm, careful consideration must be given to filtration. The standard for most consumer, occupational, and medical filtration devices is currently HEPA grade filtration (99.97% efficiency at 300 nm), which would allow in excess of 10 million particles to pass through for every cubic meter of air that is filtered.
In order to ensure filtration at efficiencies that will eliminate the potential for harmful reactants resulting from high concentrations of unknown airborne chemicals reacting with drugs, both the filter material and overall filter design should be chosen carefully. Filter materials that are capable of these efficiencies (e.g., Lydall Filtration's 6850 grade) are readily available. This technology has been used extensively in settings such as clean rooms, but its use in smaller applications for breathable air such as that described herein is not seen elsewhere in the art. It will be appreciated that, with clean rooms being the principal application for this material and where rapid room air changes are typical, the above, highly efficient filter material is engineered with high flow rates in mind. In such a high flow application, the air passes through the filter material at relatively high velocity. Therefore, the pollutant particles in such an application strike the filter material at a relatively high velocity. The rate of particle penetration depends largely on the kinetic energy of the particle (½mv2) with particle penetration increasing with velocity. This velocity is termed “face velocity” in the filter industry. The graph in
Based on this information, the goal for maximum filtration efficiency is to utilize the filter materials described above at relatively low face velocities. At a given flow rate, face velocity is inversely proportional to filter area. Thus, the present disclosure uses larger areas than required to satisfy pressure drop requirements in order to establish very low particle velocities, thereby providing the extremely high efficiencies that are important for combining drugs and purified air. At the same time, flow rates equal to or above that of existing devices is achieved.
As indicated above, filter efficiency in this range and with representative glass microfiber technology (e.g., ULPA grade filters such as those from Lydall Filtration/Separation, Inc., Rochester, N.H.) is achieved when the face velocity drops below 2 cm/sec, and full efficiency is realized as it approaches approximately 1 cm/sec. In preferred embodiments of the present disclosure, air flow rates to the user are approximately 320 slm. With indoor and outdoor particle concentrations at times in excess of 10 billion per cubic meter, filter efficiencies should be very high to ensure that unwanted chemical reactions do not occur between particles and drugs. This is particularly important for small particles (e.g., below 100 nm) that have high surface to area ratios. As stated above, the chemical composition of particles will vary greatly as a function of location, weather, etc. Therefore the near elimination of these potential reactants is important in order to have confidence in the drugs (chemicals) ultimately delivered. As also discussed above existing respirators achieve a filtration efficiency of approximately 99.97% at 300 nm. With indoor air particle concentrations of about 10 billion particles per cubic meter and a pulmonary inspiration volume at rest of up to about 5 liters, filtration at about 99.97% means existing respirators allow passage of more than about 15 thousand particles per inspiration of sizes equal to 300 nm in diameter and more than 150 thousand at sizes of about 25 nm and smaller, which provides an environment where unsafe chemical reactants can result from interactions between these high particle concentrations and injected drugs.
The systems of the present disclosure achieve a high degree of confidence in the chemical composition of delivered medications (e.g., a filtration of about 99.9996%). With the above-described preferred embodiment, the filter area would typically exceed about 500 cm2 for this level of filtration. Filter areas of about 2700 cm2 up to 5400 cm2 in area can be utilized, resulting in filter efficiency of about 99.99996% and about 99.99999% respectively, and corresponding passage of only hundreds of particles per inspiration. In another embodiment, with a flow rate of about 160 slm (adequate for the respiratory requirements of an adult at rest), efficiencies of 99.9996% would be realized with filters areas as low as about 250 cm2 with maximum efficiencies occurring for areas greater than about 2700 cm2. In yet another embodiment (
Filtration of particulate matter that is present in the air and which forms as a result of reactions between organic particulate matter and ozone a significant improvement; however, ozone, as a molecular level substance, is not removed by simple mechanical filtration and will remain as a pollutant in filtered air. Thus, in some embodiments it is desirable to remove by a reaction or catalytic process in which it is converted to molecular oxygen or into other compounds that are not harmful or that are much less reactive than ozone. One readily available method for reducing or eliminating ozone is the use of an activated carbon filter. This method is achieved through the adsorption of ozone as the air passes over the large surface areas presented by the activated carbon. The activated carbon material may be impregnated into a filter material or alternately, in granulated form, held in place between two layers of filter material. However, the performance of the activated carbon filter deteriorates over time due to the buildup of adsorbed materials and resultant compounds on the surfaces of the carbon. The filter must be continually replaced. Thus, a preferred embodiment includes catalyst that assists in the conversion of ozone ultimately to O2. MnO2 (both γ-MnO2 and β-MnO2), as well as palladium or palladium oxides, Ag2O, or other metal oxides such as aluminum oxides and/or copper oxides can be used as a catalyst and can be applied as a coating on surfaces of the delivery device that are in contact with the airstream. The material can also be incorporated into the filter material itself either by impregnation or adhering particles of the catalyst to the filter's fiber matrix. In an exemplary embodiment, the catalyst is incorporated into the chemical makeup of glass fibers of the filter.
Another benefit to the use of a MnO2 catalyst is that the chemistry involved is also useful for removing SO2, which is another major air pollutant. Another common pollutant, NO2, may be catalyzed using different chemistries and with some energy input to drive the reaction. One example is the photocatalysis of oxides of nitrogen when exposed to an irradiated surface of TiO2. Therefore, additional embodiments of the methods and systems of the present disclosure include using purified air that has also had one or more of ozone, SO2, and NO2 effectively removed.
The present disclosure further provides a method and system for supplying the drugs or medication into an air stream, thereby delivering the medication via normal respiration. This is in contrast to albuterol inhalers and other similar devices, which require some extra effort and coordination of the user's inhale cycle with the operation of the device. Typically, drugs are provided to patients in solid, granular, or powder form and are administered as tablets or capsules, or the drug is provided in liquid form and is taken orally (e.g., cough syrup), or is injected into muscle tissue or injected intravenously. Other drugs in turn rely on a delay or slow release mechanism, such as the patch that relies on absorption through the skin. Oral, injection, intravenous, and transdermal delivery methods all have significant drawbacks. Significant hurdles must be overcome for oral delivery of medications due to the requirement that the drug must react correctly to the chemistry of the digestive system. Additionally, once absorbed by the digestive tract, yet another barrier to entering the bloodstream is first pass metabolism in the liver. The obvious drawback to injections and intravenous delivery is the invasive and painful nature of the method, the risk of infection, and the psychological impact of needle insertion. Transdermal delivery, while moderately effective for some readily absorbed drugs like nicotine, is not an efficient means of delivering most drugs.
Pulmonary delivery of drugs avoids all of these issues. Drugs delivered by this route are not subject to complications with digestive tract chemistry and drugs absorbed by the lungs bypass the liver and are therefore not subject to first pass metabolism as are orally delivered drugs. Pulmonary delivery is non-invasive, requiring no needles or surgery. It is well known within the medical field that given the large surface area and sensitive nature of the membranes lining the lungs, that pulmonary delivery is a fast and efficient means of getting medicines into the bloodstream.
Another aspect of the system of the present disclosure is the ability to accurately monitor the pressure and flow parameters of the filtered and medicated air being supplied to the user. Existing devices typically rely on the delivery of either a constant source of medicated aerosol delivered to some vessel or canister through which the user must draw air by his/her own effort or on a system such as an albuterol inhaler, which requires the action of the user for delivery (e.g, the albuterol canister must be depressed in coordination with inhalation). In contrast, embodiments of the present disclosure employ state-of-the art electronic sensors and processors to actively monitor and respond to the respiratory cycle of the user. An array of solid state pressure transducers such as the SM5600 series sensors produced by Silicon Microstructures of Milipitas, Calif. are used to monitor the pressure conditions within the medical port. Data from the sensors are monitored in real-time by an on-board microprocessor that stores the data collected from the sensors. Through analysis of this data the processor can establish or “learn” baseline respiratory parameters of the user based on approximately one or two minutes worth of data. Once baseline parameters are established the processor may react appropriately to the user's unique requirements and breathing patterns. As one example, the processor may observe pressure readings to detect a particularly rapid or deep (large volume) inhale cycle at its onset. In this manner the processor may cause the port to inject a precisely controlled amount of medicine in the airstream at precisely the correct time for it to be most deeply and effectively inhaled by the user. In another case, the medical port, as controlled by the processor, may administer drugs only during alternate inhalations. The processor may receive input from “smart” drug cartridges in a manner similar to the way ink jet printers for personal computers receive data from ink jet cartridges. This data may be used to instruct the processor regarding the optimal parameters for delivery for the drug and the patient as determined by a doctor of pharmacist. Such data might include information on dosages, proper timing of the dose with the user's respiratory cycle, etc. In one embodiment, the medical port has a data port which may be connected to a device for delivering feedback on the user's condition. As an example, a blood oxygen saturation monitor is used to monitor the user's blood oxygen content and respond appropriately with medications.
Obviously, medicated air could also be delivered in a precisely mixed and continuous fashion if so required. Yet another unique application is for slow and accurate delivery of medicines which are currently delivered as a periodic bolus (such as delivery of albuterol by an inhaler). Slow, gradual delivery of medicines such as albuterol allows patients to receive more appropriate doses without the side effects that come with sudden infusions (such as the “jitters” associated with albuterol inhalers and nebulizers). Existing devices also do not exhibit the ability to deliver inhaled drugs accurately and appropriately for the drug in question and at precise times during the respiratory cycle. The present disclosure provides a method and system for allowing drugs to be administered to the respiratory system of the patient, particularly the lungs, and, furthermore, allows the effectiveness of a drug to be optimized by monitoring the respiratory cycle and controlling the timing by which the medication is administered. By providing the drugs in a purified air stream and in a positive pressure environment, the systems and methods of the present disclosure also make it easier for people with limited respiratory strength and limited coordination, such as children or the elderly, to be effectively medicated.
In addition to removing unwanted pollutants and effectively delivering medications, the present disclosure allows for the temperature and humidity of the air supplied to the user to be controlled so that the most effective conditions for drug delivery and for the comfort of the user are ensured. This is done by the controller using data generated by a temperature and relative humidity sensor such as the HTS2030SMD that is currently available from America Humirel, Inc. in Chandler, Ariz. The controller monitors the output of the sensor in order to determine if there is a need to add humidity or remove humidity or raise/lower the temperature of the air stream. The controller can then initiate the appropriate conditioning. Temperature can be raised or lowered using a thermoelectric cooler/heater or an electric resistance heater to modify temperature. It may also initiate the injection of water vapor into the stream to add humidity. Humidity may also be lowered by using an auxiliary condenser or a desiccant as a dehumidifier.
One embodiment makes use of an active type of face mask similar to that described in U.S. patent application Ser. No. 11/533,529, which is incorporated herein by reference in its entirety, is shown in
The medical access port 2440, which will also be referred to as a medi port 2440. The medi port 2440 comprises a hose adaptor housing 2450 having an air inlet 2452 and an air outlet 2454. In one embodiment, each of the air inlet 2452 and the air outlet 2454 can be provided with a seal arrangement. In one embodiment, the seal is a gasket having three parallel annular ridges to provide more reliable sealing. As shown in this embodiment, the medi port 2440 is connected in the hose 2424. Thus portions of the hose 2424 connect to both the air inlet and the air outlet 2452, 2454. In other embodiments, discussed below, the medi port is connected either at the inlet end or outlet end of the hose 2424. While ease of use may favor the use of a medi port at the inlet end of the hose where the user can readily see what he or she is doing, it is typically preferable, especially in the case of nebulized medicines, to have the medi port as close to the mask as possible. This avoids condensation of medicine along the hose wall and also minimizes any chemical reaction with the pipe material that may cause the pipe to degenerate or cause leaching of undesirable polymers from the pipe into the air stream. In particular, in the embodiment of
In the embodiment of
As will become clearer from the explanation below, the medi port acts as a vehicle for introducing medication in vaporized or nebulized form into the air stream created by the air mover 2402. This medication is then transported to the user via the hose 2424 or administering the medication to the user. The mask used for this purpose is preferably a fitted mask to allow for precise pressure and flow measurement and therefore dosage control. Also, some embodiments can include a pressure sensor in the mask or hose or elsewhere in the system to detect a loss of positive pressure in the mask and an indicator (visual or audible) of an undesired loss of pressure. In the embodiment of
As discussed above, the medi port includes two sections: a hose adaptor and a mixing chamber.
For greater flexibility, embodiments of the presently disclosed device also include an adaptor 5000 for accommodating different size bottles or canisters. In particular, the adaptor 5000 includes a wider input opening for large bottles and canisters. The wider opening includes triple valves 5004 and edge stop 5006 that limits any large bottle from passing the line 5002. The adaptor also includes a second narrower input opening for smaller bottles and canisters, the narrower opening having a seal 5014 for engaging the outer surface of smaller canisters or bottles. In this case the edge stop 5016 stops the bottle or canister at line 5010. It will be appreciated that when the adaptor is used, the adaptor rather than the bottle or canister is slipped into the mixing chamber 4000. Thus when a large bottle is inserted into the adaptor the internal air space is defined by both the mixing chamber space between the wall 4004 and the valve 4006 (depicted by the letter A), as well as the air spaces B and C in
It will be appreciated that other configurations for the mixing chamber and adaptor can be devised without departing from the scope of the present disclosure.
An aerosol is typically provided in the form of a canister such as an albuterol canister, which is typically engaged with the mixing chamber in the manner discussed above. By pressing the canister inward so that its nozzle impinges upon a pin in the chamber such as pin 4020 or a pin in the adaptor, such as pin 5020, a dose of medicine in the form of a puff or bolus is dispensed into the chamber.
Solids in the form of tablets may be placed in the mixing chamber or the adaptor, an embodiment of which is shown in
Furthermore, while the embodiment of
One embodiment contemplates a removable, disposable adaptor that is sold with the medication in place, thereby eliminating the need for an inlet opening to the adaptor. Such an embodiment will only provide a single dose per adaptor.
While the above embodiments all show a mixing chamber and a chamber adaptor extending laterally outwardly, the present disclosure is not so limited. One embodiment makes use of a vertically mounted chamber adaptor as shown in
Yet another variation of an adaptor, which is suitable for receiving a bottle or a canister is shown in
As discussed above, in the case of a liquid or solid medication that is neither in nebulized form nor in aerosol form, a vaporization step has to take place. The vaporizing can be achieved by providing energy to the medication, such as by actively heating the medication. Instead of heat, other forms of energy can be provided to the medication to vaporize it. For instance, physical shaking or the use of ultrasonic agitation can be used as by the agitator 8010 shown in
Instead, the medication may be of such a nature that it readily vaporizes without external intervention, e.g., passive vaporization.
The above discussion has focused on dispensing the medication into the mixing chamber in aerosol or nebulized form suitable for transportation in an air stream or alternatively dispensing in a form that requires subsequent vaporization. Another important aspect involves the introduction of the aerosol, nebulized, or vaporized medication into the air stream. This involves transferring it in a controlled manner from the mixing chamber into the adaptor housing 2450, 3500, 3502, 4050.
Any suitable method of moving the medication from the mixing chamber into the air stream of the hose adaptor can be used. In one embodiment, the vaporized, nebulized, or aerosol in the mixing chamber 8000 is drawn out by creating a Venturi effect by means of a curved pipe 8002 as shown in
Another embodiment making use of the Venturi effect to pull or draw the material from the chamber is shown in
Instead of or in addition to a Venturi device to suck out the material from the chamber, an air stream can be directed into the chamber to push the material out. The embodiment shown in
In yet another embodiment the mixing chamber is pressurized e.g., by an external source of a pipe leading to the chamber from a higher-pressure region in the system. This increased air pressure in the chamber serves to push the medicated air out of the chamber whenever the valve between the chamber and the hose adaptor is open.
While the above embodiments have relied on low pressure or an air stream to move the material out of the chamber and into the hose adaptor, another embodiment makes use of a physical propulsion mechanism in the form of a piston 11000, as shown in
In order to control expulsion of air from the mixing chamber into the hose adaptor, a valve mechanism is provided such as the electronic valve 4006 in
The controlled manner in one embodiment includes releasing some of the medication every time the user inhales. In one embodiment, the controller monitors the inhalation and exhalation and releases medication according to a certain series, e.g. every second or third inhalation, or two inhalations in a row followed by three inhalations where no medication is dispensed. The pattern or series may be changed depending on the nature of the medication. In addition, air pressure or air flow may be taken into account to vary the size of the aperture or the amount of time that it is open, depending on how deeply the person is breathing in. Also, in one embodiment, a button, momentary switch, or some other device for signaling the controller is employed to indicate the user's wish that medication be delivered upon some future event, such as the next inhalation cycle. In this manner the drug could be delivered periodically as preferred by the patient while the benefit of timed delivery is preserved. In another embodiment, the medication can be provided in a continuous manner, rather than in pulses.
As discussed above, the system will include sensors for indicating the rate of flow of air to the user, the output from which will be used by a controller to calculate dosing parameters. The flow in this application may be measured by a number of methods. It may be measured directly by means of a hot wire anemometer, mechanical anemometer, or mass air flow sensor placed in contact with the air stream flowing through the port. Preferably, flow sensing would be performed indirectly using pressure sensors. These sensors can be used with a pitot tube, or some number of sensor, (e.g., three) are placed with access to the air stream on each side of the venturi structure within the port. The controller, based on pressure as measured by the sensors, can then monitor the pressure differential across the venturi and calculate flow based on this information. Use of multiple sensors would allow the controller to average the data, and occasional erroneous readings from individual sensors due to turbulence, etc. could be omitted in order to yield an accurate set of data upon which to base the control of the port functions. In addition, if at least one pressure sensor is included to measure atmospheric pressure, the controller will also be able to monitor the pressure within the medical port, hose, and mask in order to determine if the wearer's respiration creates a negative pressure, indicating inadequate performance of the blower unit. In one embodiment, the controller that controls air flow rate or pressure by controlling power to the air mover may include an algorithm for controlling the shutter or valve to release medication in a controlled manner.
The pressure sensors or flow sensor may be mounted in the adaptor housing and any holes in the adaptor housing or tube for passing wires out of the housing are sealed. This may be done by potting the adaptor housing. In one embodiment, all the sensors and monitors in the adaptor housing are mounted on a printed circuit board that snaps onto an inner surface of the housing by means of clips. To avoid the electronics being exposed to the air stream, a conformal coating is provided over the circuit board with its components. While the controller can also be mounted on the circuit board, the sensors and monitors in another embodiment are connected to a monitor on an external circuit card, or in the air mover housing. In an embodiment where insulin is being administered to the lungs, the device of the present disclosure provides a feedback loop from an insulin monitor to the controller to automatically calculate the requisite amount of insulin to administer based on the detected blood/sugar levels in the user's blood.
In the embodiment where the controller is mounted on the circuit board, wires out of the medi port can be eliminated altogether by providing a separate power supply on the circuit board, e.g., by way of a watch battery.
Power supply to the medical port can also be provided by energy sources such as solar cells, small wind turbines, or fuel cells for use in areas where access to an electric grid is not possible or convenient.
In order to ensure accurate amounts of medication are delivered to the user, it is important to control the amount of drug or chemical introduced into the mixing chamber and the rate of air flow out of the port (into the air stream). If both of these values are known, then the mixing rate and delivery rate may be determined and controlled. The system may deliver a fixed amount of drug to the mixing chamber and then allow this mixture to be drawn from the chamber at the appropriate moments and over the appropriate amount of time, or it may deliver drugs to the mixing chamber as a continuous process.
Once the medication in the chamber is transferred into the air stream it is carried by the hose 2424 (
In embodiments the hose includes an inner lining, the hose is made of a material that does not leach polymers into the air stream, as may otherwise occur, especially with certain kinds of medicines. Furthermore, in embodiments the hose is made from a material or lined with a material that prevents or reduces chemical degradation from exposure to the drug. In yet another embodiment, the hose is releasably connected to allow it to be replaced from time to time. This allows the issue of degradation and drug residue accumulation on the hose inner surface to be addressed.
While the above discussed embodiments have made use of a shutter or an electronically controlled valve between the mixing chamber and the adaptor housing, another embodiment provides the shutter or valve to be mounted in the mixing chamber. Such an embodiment is shown in
In the case of a canister, a pin 16034 impinges on the nozzle to allow a bolus of medication to be expelled into the upper section 16010. In the case of a liquid dispensed from a bottle or other liquid dispenser, a heating pad or piezo plate 13036 vaporizes the liquid. The air pressure in the upper section 16010 created by the air entering through the hole 16024 forces the air into the lower section 16012 whenever the valve 16004 opens.
The medication is drawn into the channel 16040 of the adaptor housing 16020 by virtue of a Venturi effect created by a curved surfaces 16042, 16044 at the inlet to the adaptor housing 16020. In this embodiment, the adaptor housing 16020 is bifurcated into a medication carrying channel 16040 and a non-medicated air stream channel 16048 to allow air to bypass the Venturi region 16042, 16044 and not force medicated air upon the user.
In one embodiment, illustrated in
This bifurcated adaptor housing is further illustrated with respect to the embodiments illustrated in
As discussed above, the dispensing of the medication into the mixing chamber or the delivery into the air stream may be controlled by a controller on a circuit board in the medi port or by a controller mounted in the blower housing. In embodiments, the drug container has a memory stick attached and may be preprogrammed, e.g., at the factory, to a predefined set of parameters, or by a pharmacy to suit the particular drug, drug concentration, type of dispensing device, age of user or dosage, and any other relevant parameter to dispense according to the particular usage. Programming can be achieved by making use of a wireless interface, e.g., Bluetooth, Zigbee, etc. It will be appreciated that the controller will also gather real time data such as differential pressure, flow rate, inhalation volume of air over time, etc. The controller can utilize this data to adjust drug delivery at the mediport to maintain desired dosage levels. Communication from a controller mounted in the blower housing to the mediport may be via a wire or wireless.
In addition, as illustrated in
In the embodiment shown in
In addition, because in a preferred embodiment, the device can measure the depth and volume of each inhalation cycle, drug delivery can be triggered to occur only in inhalation cycles with a high volume and that are optimal for drug delivery. This is done by continuously measuring the recent history of inhalation cycles for a specific user over the period of several minutes and then comparing the slope and depth (prior to reaching the deepest level of the cycle) of the inhalation curve to trigger drug release during an inhalation. Multiple input measurements may be utilized to confirm certain conditions such as a sudden decrease in cardiac output which would trigger the release of specific drugs and/or, in another embodiment described elsewhere in this application, increase oxygen levels in the inhaled air.
While the above embodiments all make use of a hose to transfer the medication to the face mask, the present disclosure is not so limited. In one embodiment, for example, the medi port is connected directly between a face mask and an air mover housing without any hose being used. Typically the medi port in such a configuration will define an adaptor housing for receiving the outlet from the mixing chamber, and for connecting between the mask and the air mover housing.
Once the medication reaches the mask, the user simply inhales the medication. By providing the ability to deliver only small quantities of medication over a period of time, absorption of the medication is improved. As discussed above, the mask is preferably a fitted mask to minimize the escape of air along the periphery of the mask. One embodiment makes use of a split manifold for supplying air to both the mouth and nose regions of the user. In one such embodiment, a slider is included to physically vary the ratio of air to the nose relative to the air to the mouth. In another embodiment, instead of a mask that covers both mouth and nose, a partial mask for only the nose or only the mouth may be used.
It is anticipated that protection against the delivery of the incorrect drug or incorrect dosage will be incorporated in this system for use with some drugs. These drug and user identification systems may involve simple color coding of medicine containers or geometry constrictions that prevent adult dosages of medicines from being administered from mask systems that fit children. More sophisticated systems may package medicines in containers incorporating bar code or RFID (radio frequency identification) tags that can be checked by the microprocessor in the mask system to confirm the correct drug and correct dosage. In this system, prescriptions may be downloaded to the mask microprocessor, perhaps by an RF protocol such as Bluetooth or Zigbee or by another RFID tag. Such prescriptions inform the mask system of the drug and dosage for the person using the mask. Advanced versions of the system may even confirm the identity of the mask user by their own RF tag or a password. Similarly, statistics of mask use, including user, time and date of use and system condition to confirm correct delivery of medications. This may be especially be done in situations where the recipient of the drug may need to be monitored due to poor memory, attention or because treatment is subject to substance addiction.
It is also anticipated that it may be desirable to prevent small quantities of certain drugs from reaching room air and other non-medicated occupants via being in exhaust air from person's lungs. For example, if a person is using the mask system for providing low dosages of nicotine it is desirable that this potentially addictive substance is not inhaled by other room occupants, even in low doses. This is accomplished by filtering air exiting the mask through filters capable of removing small particles, or even in some cases of chemically deactivating the drub by materials such as activated carbon. In addition, it should be known that the particle filter mentioned above, in a preferred embodiment would be a sterilization chamber fabricated from materials such that the interior surfaces have a high reflectivity in about the 250 nm to 280 nm wavelength range. The sterilization chamber utilizes ultraviolet light generated by mercury vapor lamp(s), light emitting diodes, or other light emitting opto-electronic devices (all such devices emitting UV radiation between about 250 nm and 280 nm) to destroy the RNA or DNA of any airborn pathogens exhaled by the user.
For added comfort, a highly flexible mask is contemplated having a central more rigid portion to define an air space in front of the user's mouth and nose, or that gradually becomes more inflexible toward the mouth and nose region and is most flexible along the periphery. The mask also includes multiple parallel extending seals along the periphery of the mask to provide a better seal to the user's face. In highly critical applications, where any contamination from the outside is to be avoided and reliance on the positive pressure in the mask and the multiple seals is not enough, it is proposed to secure the mask to the user's face by means of an adhesive which makes removal of the mask more difficult and may even require a solvent.
Additionally, to increase compliance for pediatric patients, some embodiments can employ masks molded and decorated to resemble cartoon characters or animals that would entertain children and increase their emotional comfort level with the device. Similarly, the mask can be made in a variety of colors that would be more appealing to both pediatric and adult users. In a similar manner, a communications system using a microphone and speaker system employing a sound processor could be added to facilitate communication through the mask, or, again, to increase compliance for children and perhaps adults by adding fun features (voice harmonization, simulation of cartoon or TV characters, e.g., Darth Vader™, Spongebob Squarepants™, etc.).
While embodiments of the systems and methods of the present disclosure have been described above with respect to a delivery system employing a mask for delivery of the medication and purified air stream, it will be appreciated by those of skill in the art that the methods and systems of the present disclosure can also be employed for the treatment of intubated patients. The devices and systems described above can be modified as appropriate for use with venitlators and/or respirators adapted for use with intubated patients, as would be appreciated by one of skill in the art.
The present disclosure thus provides for a way of safely administering medication via inhalation of purified air by a patient over time in an actively and precisely controlled manner. While a number of embodiments were discussed above, it will be appreciated that the present disclosure is not limited to these embodiments but could be implemented in other ways without departing from the scope of the present disclosure.
This application is a continuation-in-part of application Ser. No. 11/552,871 filed Oct. 25, 2006 that claims priority to and the benefit of provisional application Ser. No. 60/826,271 filed Sep. 20, 2006.
| Number | Date | Country | |
|---|---|---|---|
| 60826271 | Sep 2006 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 11552871 | Oct 2006 | US |
| Child | 11627692 | US |
