Abstract:
Nebulizer assemblies and systems are disclosed. A nebulizer assembly includes a reservoir and a nebulizer for producing an aerosolized gas. An aerosolized gas outlet passes the aerosolized gas. A breathing gas mixing chamber is coupled to an outlet port of the nebulizer to entrain nebulized medication into a breathing gas. A system and method of heating medication in a reservoir and adding medication to a gas flow is also provided.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    The present application claims the benefit of U.S. Patent Application No. 61/150,368, entitled “HEATED NEBULIZER DEVICE FOR ADDING AEROSOLIZED MEDICAMENT TO A BREATHING GAS” filed on 6 Feb. 2009, U.S. Patent Application No. 61/228,304, entitled “NEBULIZER SYSTEMS AND METHODS FOR INHALATION THERAPY” filed on 24 Jul. 2009, and U.S. Patent Application No. 61/228,308, entitled “NEBULIZER FOR ACCELERATED AEROSOL DELIVERY WITH FLOW CONTROL” filed on 24 Jul. 2009, all of which are incorporated herein by reference in their entireties. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    Patients with respiratory ailments may be administered supplemental breathing gases, such as oxygen, for example, to aid in respiration. These breathing gases may be provided from a breathing gas supply, such as an oxygen tank. A delivery device, such as a nasal cannula, may be coupled to the breathing gas supply and inserted into a patient&#39;s nasal passages for delivery of the breathing gas to the patient for inhalation. 
         [0003]    Separately, respiratory medications may be administered through inhalation directly to the patient&#39;s lungs. These respiratory medications may be aerosolized by a nebulizer in order to generate small particles of the medication, which facilitate distribution throughout the patient&#39;s lungs during inhalation. 
         [0004]    Nebulizers produce a fine mist for inhalation by a patient. The mist may include a medicament for delivery to the respiratory tract of the patient. A conventional nebulizer uses pressurized air to form a gas jet that creates a venturi vacuum to draw liquid medicament from a liquid reservoir to form a nebulized aerosol for inhalation. 
       SUMMARY OF THE INVENTION 
       [0005]    Aspects of the present invention are directed to nebulizer assemblies, nebulizer systems, nebulizer adaptors, and methods for adding medication to a gas flow for inhalation. 
         [0006]    In accordance with one aspect of the present invention, a nebulizer assembly includes a reservoir for containing a liquid, a nebulizer for producing an aerosolized gas using the liquid, an aerosolized gas outlet, and a heating chamber. The aerosolized gas outlet is coupled to the nebulizer to pass the aerosolized gas. The heating chamber is disposed around an exterior of the reservoir. The heating chamber includes a heating fluid inlet in fluid communication with the heating chamber for providing heating fluid to the heating chamber and a heating fluid outlet in fluid communication with the heating chamber for discharging the heating fluid from the heating chamber. 
         [0007]    In accordance with another aspect of the present invention, a method of heating a medication to be nebulized and providing the nebulized medication to a patient for inhalation includes generating a heated and humidified breathing gas, transmitting the heated and humidified breathing gas through a first lumen in a delivery tube, insulating the heated and humidified breathing gas with a fluid flowing through a second lumen in the delivery tube, discharging the heated and humidified breathing gas from the delivery tube to a chamber, providing a medication in a nebulizer reservoir, transmitting the fluid from the second lumen to a heating cavity surrounding the nebulizer reservoir; thereby heating the medication in the nebulizer reservoir with the fluid, nebulizing the medication in the nebulizer reservoir, combining the nebulized medication with the heated and humidified breathing gas in the chamber, and transmitting the combined nebulized medication and heated and humidified breathing gas to a patient for inhalation. 
         [0008]    In accordance with yet another aspect of the present invention, a nebulizer system includes a nebulizer for generating an aerosol mist of a medication, and a breathing gas mixing chamber. The nebulizer includes a nebulizer outlet port. The breathing gas mixing chamber is coupled to the nebulizer outlet port. The breathing gas mixing chamber includes a nebulizer coupling port, a breathing gas inlet, a breathing gas outlet, and an opening between the breathing gas inlet and the breathing gas outlet. The nebulizer coupling port is in fluid communication with the nebulizer outlet port. The breathing gas inlet is adapted to couple to a gas delivery system. The breathing gas outlet is adapted to couple to a breathing device. The opening is in fluid communication with the nebulizer outlet port. 
         [0009]    In accordance with still another aspect of the present invention, a method of adding a medication to a gas flow includes nebulizing the medication and entraining the nebulized medication into the gas flow. 
         [0010]    In accordance with another aspect of the present invention, a nebulizer adaptor for entraining a nebulized medication into a breathing gas includes a mixing chamber, a nebulizer coupling port, a breathing gas inlet, a breathing gas outlet, and an opening between the breathing gas inlet and the breathing gas outlet. The nebulizer coupling port is adapted to coupled to a nebulizer outlet port. The breathing gas inlet is adapted to couple to a gas delivery system. The breathing gas outlet is adapted to couple to a breathing device. The opening is in fluid communication with the nebulizer coupling port. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]    The foregoing summary, as well as the following detailed description of preferred embodiment of the inventions, will be better understood when read in conjunction with the appended drawings, which are incorporated herein and constitute part of this specification. For purposes of illustrating the invention, there are shown in the drawings an exemplary embodiment of the present invention. It should be understood, however, that the invention is not limited to the precise arrangements and instrumentalities shown. In the drawings, the same reference numerals, are employed for designating the same elements throughout the several figures. In the drawings: 
           [0012]      FIG. 1  is a front perspective view, partially cut away, of an exemplary embodiment of a heated nebulizer assembly according to the present invention; 
           [0013]      FIG. 2  is a rear perspective view of the heated nebulizer assembly of  FIG. 1 ; 
           [0014]      FIG. 2A  is a sectional view of a manifold and delivery tube shown in the heated nebulizer assembly of  FIG. 2 ; 
           [0015]      FIG. 3  is a right side perspective view of the heated nebulizer assembly shown in  FIG. 1 , coupled to a nasal cannula; 
           [0016]      FIG. 4  is a left side perspective view of the heated nebulizer assembly of  FIG. 1 , coupled to a nasal cannula; 
           [0017]      FIG. 5  is a flow chart illustrating steps performed to operate the heated nebulizer assembly of  FIGS. 1-4 ; 
           [0018]      FIG. 6  is a perspective view of a prior art nebulizer system; 
           [0019]      FIG. 7  is a side elevational view of a nebulizer system according to a first exemplary embodiment of the present invention; 
           [0020]      FIG. 8  is a front perspective view of a T-adapter according to an exemplary embodiment of the present invention, for use with the nebulizer system of  FIG. 7 ; 
           [0021]      FIG. 9  is a top perspective view of the T-adapter of  FIG. 8 ; 
           [0022]      FIG. 9A  is a schematic enlarged view of an internal breathing gas mixing chamber of the T-adapter of  FIG. 8 ; 
           [0023]      FIG. 10  is a side view of a cross adapter according to another exemplary embodiment of the present invention, for use with the nebulizer of  FIG. 6 ; 
           [0024]      FIG. 11  is a side view of the cross adapter of  FIG. 10  with a heat moisture exchanger media partially inserted therein; 
           [0025]      FIG. 12  is a side view of the heat moisture exchanger media used with the cross adapter of  FIG. 10 ; 
           [0026]      FIG. 13  is a flow chart illustrating operation of exemplary embodiments of the inventive nebulizer assembly; 
           [0027]      FIG. 14  is a top plan view of an adapter according to another exemplary embodiment of the present invention, for use with the nebulizer of  FIG. 6 ; 
           [0028]      FIG. 15  is a lateral cross-sectional view of the adapter of  FIG. 14 , taken along lines  15 - 15  of  FIG. 14 ; 
           [0029]      FIG. 16  is a longitudinal cross-sectional view of the adapter of  FIG. 14 , taken along lines  16 - 16  of  FIG. 14 ; 
           [0030]      FIG. 17  is a side elevational view of a breathing gas delivery system incorporating an adapter according to an exemplary embodiment of the present invention coupled to the nebulizer assembly of  FIG. 7  and also coupled to a nasal cannula; 
           [0031]      FIG. 18  is a side elevational view of an angled adaptor according to another exemplary embodiment of the present invention, for use with the nebulizer of  FIG. 6 ; 
           [0032]      FIG. 19  is a perspective top view of the angled adaptor of  FIG. 18   
           [0033]      FIG. 20  is an angled top view of the angled adaptor of  FIG. 18 ; 
           [0034]      FIG. 21  is a side cross-sectional view of the adaptor of  FIG. 18  taken along lines  21 - 21  of  FIG. 20 ; 
           [0035]      FIG. 22  is a side elevational view of an assembled nebulizer system according to another exemplary embodiment of the present invention; 
           [0036]      FIG. 23  is a side elevational view of an unassembled nebulizer system of  FIG. 22 ; 
           [0037]      FIG. 24  is a side elevational view of the nebulizer system of  FIG. 22  with a cannula; 
           [0038]      FIG. 25  is a side elevational view of the nebulizer system of  FIG. 22  with another cannula; and 
           [0039]      FIG. 26  is a flow chart illustrating operation of the nebulizer system of  FIG. 22 . 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0040]    Certain terminology is used herein for convenience only and is not to be taken as a limitation on the present invention. The terminology includes the words specifically mentioned, derivatives thereof and words of similar import. The following describes exemplary embodiments of the invention. It should be understood based on this disclosure, however, that the invention is not limited by the exemplary embodiments of the invention. 
         [0041]    Embodiments of the present invention provide a heated nebulizer assembly  100  configured for delivering aerosolized medicament in a heated and humidified breathing gas for inhalation. The aerosolized medicament includes medication in very small particles, e.g., 0.5-1.5 microns in average diameter, allowing the medicament to reach the user&#39;s lungs in an efficient manner. Nebulizer assembly  100  is heated in order to warm the medicament prior to the medicament being nebulized so as not to adversely lower the temperature of the heated and humidified breathing gas into which the nebulized medication is mixed prior to inhalation by the user. 
         [0042]    Referring to  FIGS. 1 and 2 , nebulizer assembly  100  includes a nebulizer  110  that entrains medication in an air flow to generate an aerosolized mist for inhalation by a patient. Nebulizer  110  includes an inlet  112  that provides a connection to a supply of air (not shown), such as, for example, a high pressure air supply of between about 35 and about 50 psi, with a flow rate of less than about 10 liters per minute, and desirably, about 6 liters per minute. The supplied air in the illustrated embodiment flows through an air swirler  114  to a nebulizing chamber  118 . It is contemplated that air swirler  114  may be omitted in alternative embodiments of the present invention. 
         [0043]    Medication is contained in a reservoir  116  (e.g., in liquid form; i.e., a liquid medicament) and is aerosolized in nebulizing chamber  118  by the supplied air to form an aerosol. The aerosol exits nebulizer  110  through discharge port  120  in the direction of arrow “A” (shown in  FIG. 4 ) to an outlet tube  122 . A fill port  124  in outlet tube  122  may be used to add medication to reservoir  116 . A cap  125  is releasably coupled to fill port  124 . Cap  125  may be removed from fill port  124  to add medication to reservoir  116  and then replaced over fill port  124  after the medication has been added to reservoir  116 . As the medication is poured into nebulizer  110  through fill port  124 , a deflector  126  deflects the medication away from nebulizing chamber  118  and to reservoir  116 . 
         [0044]    A design of an exemplary nebulizer that may be modified for use as nebulizer  110  is described in U.S. Pat. No. 5,630,409, which is incorporated by reference herein in its entirety. While the nebulizer  110  described in this reference may use a pressurized air supply, other types of nebulizers may alternatively be used. Such nebulizers may include a jet nebulizer, also known as a small-volume nebulizer (SVN). In an exemplary embodiment, one of three types of SVNs are used. A first type of SVN is a pneumatic nebulizer. Pneumatic nebulizers use a pressurized gas stream to draw fluid out of a fluid reservoir and shear the fluid into small particles. Many of the medicaments that are delivered through these nebulizers are used to treat common lung conditions, such as asthma and Chronic Obstructive Pulmonary Disease (COPD). 
         [0045]    A second type of SVN is a vented nebulizer. Vented nebulizers make aerosol from pneumatic sources and feature a venting system. When the patient breathes in, he/she inhales a richer mix of aerosol, and when the user exhales, he/she does so through an expiratory valve in the mouthpiece so he/she continues to collect some aerosol in the nebulizer. 
         [0046]    A third type of SVN is a breath-actuated device. Breath-actuated devices produce aerosol when the patient inhales and do not produce aerosol when the patient exhales. Because the drug is not constantly being aerosolized, delivery is more efficient and less of the drug is wasted. 
         [0047]    Other types of suitable nebulizers for use with the present invention include, by way of non-limiting example, ultrasonic nebulizers that create aerosol using sound waves generated by a vibrating piezo crystal and vibrating mesh nebulizers that are able to generate high overall output respirable fractions. The nebulizers reduce the amount of drug that is wasted by vibrating a mesh or plate with multiple apertures, which aerosolizes virtually all of the drug solution. The vibrating mesh may be active, where the mesh is vibrated directly and acts as an electronic micropump, or passive, where an ultrasonic horn pushes medication through a mesh. 
         [0048]    According to one aspect of the invention, a heating chamber  130  surrounds medicament reservoir  116  regardless of the type of nebulizer used in the nebulizer assembly  100 . The illustrated heating chamber  130  defines a cavity  131  with the outside wall of nebulizer  110  that is in fluid communication with a fluid manifold  132 . Fluid manifold  132  includes a fluid inlet  134  that provides a supply of heated fluid to cavity  131 , and a fluid outlet  136  that discharges the heated fluid from cavity  131 . Optionally, as shown in  FIG. 1 , a baffle  137  may be located in cavity  131  between fluid inlet  134  and fluid outlet  136  to direct the heated fluid from fluid inlet  134 , around the periphery of nebulizer  110 , prior to being discharged from fluid outlet  136 . Fluid manifold  132  also includes a breathing gas supply  138  that provides heated and humidified breathing gas to a user. 
         [0049]    Referring to  FIG. 2A , fluid manifold  132  is coupled to a delivery tube  140 , such as, for example, the delivery tube disclosed in U.S. Pat. No. 7,314,046, which is incorporated herein by reference in its entirety. Delivery tube  140  provides heated and humidified breathing gas in a first lumen  140   a  that is coupled to breathing gas supply  138  in manifold  132 . Delivery tube  140  also provides heated fluid via a second lumen  140   b  that is coupled to fluid inlet  134  and heated fluid return via a third lumen  104   c  that is coupled to fluid outlet  136 . In an exemplary embodiment, the second and third lumens  140   b ,  140   c , respectively, surround the first lumen  140   a  such that the heated fluid flowing through the second and third lumens  140   b ,  140   c , respectively, insulates the heated and humidified breathing gas in the first lumen  140   a . Fluid manifold  132  enables fluid that is used to insulate the heated and humidified breathing gas as the breathing gas flows through delivery tube  140  to also be used to surround and heat heating chamber  130 , as well as the medicament in nebulizer reservoir  116 . While a fluid that is used to insulate the heated and humidified breathing gas delivery tube  140  and to also surround and heat the heating chamber  130  may be a liquid, those skilled in the art will recognize that the fluid may be a heated gas instead. 
         [0050]    Referring to  FIGS. 2-4 , breathing gas supply  138  is coupled to a breathing gas conduit  142  that is in fluid communication with discharge port  120  through outlet tube  122 . Breathing gas flows in the direction of arrow “B” (shown in  FIG. 4 ). One end of outlet tube  122  includes a relief valve  152  that relieves overpressurization in outlet tube  122 . An opposing end of outlet tube  122  is coupled to a chamber, such as a breathing gas flow tee  160 , forming a junction between nebulized gas and breathing gas. Breathing gas flow tee  160  includes a first end  162  that is coupled to breathing gas conduit  142  and a second end  164  that is coupled to a nasal cannula  170 . 
         [0051]    Referring to  FIG. 5 , a flowchart is illustrated showing an exemplary method for heating a medication to be nebulized and providing the nebulized medication to a patient for inhalation. It will be understood by one of ordinary skill in the art that, prior to the steps shown in  FIG. 5 , a heated and/or humidified breathing gas may be generated by any known means. 
         [0052]    In STEP  500 , heated fluid in the second and third lumens of delivery tube  140  insulates a heated and humidified breathing gas flowing through first lumen  140   a  of delivery tube  140 . The heated fluid flowing through second lumen  140   b  of delivery tube  140  may have a temperature of about 43 degrees Celsius when it reaches manifold  130 . In STEP  502 , the heated fluid from second lumen  140   b  passes through manifold  132  to fluid inlet  134 , and into cavity  131 , which heats the medication in reservoir  116 . In STEP  504 , the heated fluid then exits cavity  131  through fluid outlet  136 , which flows through manifold  132  to third lumen  140   c  of delivery tube  140  for recirculation by, for example, a heater of a humidifier (not shown). 
         [0053]    In STEP  506 , high pressure air flows into nebulizer  110  through inlet  112  and, due to a venturi effect, draws medication from reservoir  116  to nebulizing chamber  118  where the medication is aerosolized. In STEP  508 , the aerosol exits nebulizer  110  through discharge port  120  to outlet tube  122 , and then to a chamber, such as breathing gas flow tee  160 . 
         [0054]    In STEP  510 , the breathing gas flows from first lumen  140   a  of delivery tube  140 , into manifold  132 , and then into breathing gas conduit  142  and into a chamber, such as breathing gas flow tee  160 , where the breathing gas mixes with the aerosol. The breathing gas flows at a rate of about 10 liters per minute. In STEP  512 , the breathing gas/aerosol mixture then flows to nasal cannula  170  in the direction of arrow “C” (shown in  FIG. 4 ) for inhalation by the patient. The breathing gas/aerosol mixture may have a temperature of about 37 degrees Celsius at the output of nasal cannula  170  to a user (not shown). 
         [0055]    Embodiments of the present invention are also directed to a device for providing a nebulized aerosol gas therapy to a patient delivered via a breathing device, such as a nasal cannula. In an exemplary embodiment, a breathing gas is warmed and humidified for combination with a nebulized aerosol for delivery at a high flow rate. The combined therapy of warm nebulized medication and high flow therapy for patients experiencing stressful respiratory episodes in acute respiratory compromise may provide a comfortable and effective technique in decreasing bronchial responsiveness while maintaining delivery of high FiO 2  to improve oxygen saturation level and decrease work of breathing. 
         [0056]    An exemplary nebulizer that may be adapted for use with the present invention may be the Aeroneb® Professional nebulizer  601 , shown in  FIG. 6 , available from Aerogen, Ltd of Galway, Ireland. Nebulizer  601  includes an aerosol generator (not shown) that aerosolizes medication contained within nebulizer  601 . Typically, less than about 10 ml of medication is used with nebulizer  601 . Nebulizer  601  also includes a nebulizer inhalation tube  602  into which nebulized medication flows for inhalation by a user. Inhalation tube  602  includes an inlet end  602   a  that is open to atmosphere during use and an outlet end  602   b  that is inserted into the user&#39;s mouth during use. 
         [0057]    During use, the user inserts end  602   b  of nebulizer inhalation tube  602  into his/her mouth and inhales. As the user inhales, air from the atmosphere flows through end  602   b  and into nebulizer inhalation tube  602 . The inhaled air, with the aerosolized medication entrained therein, then flows through end  602   b , and into the user&#39;s mouth. Other types of nebulizers suitable for use with the present invention will be understood by one of skill in the art from the description herein. 
         [0058]    Referring to  FIGS. 6 and 7 , exemplary prior art nebulizer  601  operates using an electrical signal to draw fluid into a vibratory aerosolization element (not shown), to produce an aerosol mist of a medication in the form of a low velocity nebulized aerosol cloud  603 . In accordance with an aspect of the present invention, nebulizer  601  may be combined with a high flow heated and humidified gas delivery system  604  to provide a warmed and humidified nebulized aerosol high flow therapy for delivery via a breathing device, such as a nasal cannula  606 . In accordance with this aspect, nebulized medication produced by the nebulizer  601  is entrained within a breathing gas flow as the breathing gas flow (which may be heated and humidified) flows past an outlet port  609  of nebulizer  601 . 
         [0059]    Nebulizer  601  includes a filler cap  608  at the top of nebulizer  601  and an outlet port  609  at the bottom of nebulizer  601 . Filler cap  608  may be removed to add liquid medication to nebulizer  601  prior to use. 
         [0060]    As shown in  FIG. 7 , a nebulizer system  600  according to an exemplary embodiment of the present invention may include a T-adapter  610  that connects nebulizer  601  to delivery system  604 . In the exemplary embodiment, nebulizer inhalation tube  602  has been removed from nebulizer  601  and replaced with T-adapter  610 . 
         [0061]    Delivery system  604  may include a delivery tube  612 , such as, for example, a delivery tube disclosed in U.S. Pat. No. 7,314,046, which is incorporated fully herein by reference, connected to a supply end of a breathing gas supply (not shown). T-adapter  610  may also connect to nasal cannula  606 , providing for fluid communication between delivery system  604  and nasal cannula  606 . 
         [0062]    Referring to  FIGS. 8 and 9 , T-adapter  610  includes a body  611  defining an internal breathing gas mixing chamber  615 . T-adapter  610  includes a nebulizer coupling port  614  that couples T-adapter  610  to nebulizer  601 . Nebulizer coupling port  614  provides for fluid communication between nebulizer outlet port  609  and internal breathing gas mixing chamber  615  such that aerosolized medication may be transmitted from nebulizer  601  to internal breathing gas mixing chamber  615 . 
         [0063]    T-adapter  610  also includes a breathing gas inlet  616  having a first end  616   a  extending from body  611  and a second end  616   b  extending through breathing gas mixing chamber  615  of T-adapter  610 , terminating within breathing gas mixing chamber  615  between second end  616   b  of breathing gas inlet  616  and a breathing gas outlet  618 . Outlet  618  extends outwardly from body  611  and is adapted to couple to a breathing device, such as nasal cannula  606  (shown in  FIG. 7 ). First end  616   a  extends from body  611  and is adapted to couple to gas delivery system  604  (shown in  FIG. 7 ). Inlet  616  and outlet  618  are generally co-axial, with an opening, such as a small gap  622  of about 5 millimeters or less (e.g., about 2 millimeters) separating second end  616   b  of inlet  616  from outlet  618 . A schematic view of internal chamber  615  showing gap  622  is shown in  FIG. 9A . Solid arrows “A” illustrate the flow of breathing gas through chamber  615  from delivery tube  612 , and broken arrows “B” illustrate the flow of aerosolized medication through chamber  615  from nebulizer  601 . 
         [0064]    In use, referring to  FIGS. 7-9A , aerosol cloud  603  is generated by nebulizer  601  and flows into internal chamber  615  of T-adapter  610 . Breathing gas flows from heated and humidified gas delivery system  604  and into inlet  616 . In an exemplary embodiment, the breathing gas has a high flow rate, e.g., greater than about one (1) liter per minute for neonatal patients and up to 40 liters per minute in adult patients. The breathing gas exits inlet  616  from second end  616   b , crosses gap  622 , and flows through outlet  618 . 
         [0065]    Aerosol cloud  603  is drawn through gap  622  and into outlet  618  by a Venturi effect generated by a flow of gas across gap  622 , and into outlet  618 , thereby entraining the aerosol into the gas flow. The aerosol cloud  603  combines with the gas and exits through outlet  618  for delivery to the patient via nasal cannula  606 . 
         [0066]    In an alternative embodiment of a nebulizer system shown in  FIGS. 10-12 , instead of T-adapter  610 , a cross adapter  1010  is used. Cross adapter  1010  includes four ports, including a nebulizer coupling port  1014 , an inlet port  1016 , and an outlet port  1018 , similar to nebulizer coupling port  614 , breathing gas inlet  616 , and breathing gas outlet  618  disclosed above with respect to T-adapter  610 . 
         [0067]    Cross adapter  1010  further includes a drain port  1019  that allows condensed medication and/or humidification vapor (in the form of rainout) to drain away from the flow of breathing gas. Drain port  1019  is disposed at a low point in cross-adapter  1010  and is positioned below nebulizer coupling port  1014  in order to allow gravity to drain liquid to a drain collector  1020  that is coupled to drain port  1019 . Drain port  1019  includes a slit  1021  that allows liquid to drain away from cross adapter  1010 . 
         [0068]    A heat moisture exchanger (HME) absorbent media  1022  may be inserted into drain collector  1020 , as illustrated in  FIGS. 11 and 12 , to absorb the condensate that drains into drain port  1019 . Exemplary HME-absorbent media  1022  includes a hygroscopic material, such as, for example, Hygrobac S, manufactured by Mallinckrodt of Haxelwood, Mo. or THERMOVENT® HEPA, manufactured by Smiths Medical International of Watford, UK. 
         [0069]    Illustrated drain collector  1020  includes a removable cap  1024  that may be removed to replace a used HME-absorbent media  1022  with a fresh HME-absorbent media  1022 . Optionally, HME-absorbent media  1022  may be coated or infused with a colorant responsive to fluid present in media  1022  in order to indicate that media  1022  is full of fluid and must be replaced, as well as to ensure the non-reuse of the media  1022 . Still optionally, HME-absorbent media  1022  may be coated with an anti-microbial material to reduce the growth of bacteria on/in HME-absorbent media  1022 . 
         [0070]    Operation of nebulizer system  600  will be discussed with reference to  FIGS. 6-9A , as well as flow chart  1300  of  FIG. 13 . While nebulizer system  600  with adapter  610  is discussed, those skilled in the art will recognize from the description herein that nebulizer system  600  with any alternative adaptor disclosed herein is also applicable. 
         [0071]    In STEP  1302 , a user (not shown) operates nebulizer  601  to nebulize medication according to the operation of nebulizer  601 . In STEP  1304 , the nebulized medication is transmitted into mixing chamber  615 . Simultaneously with STEPs  1302  and  1304 , in STEP  1306 , gas, which may be heated and humidified, is transmitted from inlet port  616 , across gap  622 , and to outlet  618 . In STEP  1308 , the gas flow draws the nebulized medication into gap  622  to outlet port  618 , thereby entraining the nebulized medication into the heated and humidified gas flow. 
         [0072]    In STEP  1310 , the gas flow with the nebulized medication is transmitted to a breathing device, such as, for example, nasal cannula  606 , for inhalation by the patient. Optionally, in STEP  1312 , when adapter  1010  is used, nebulized medication that is not drawn into gap  622  may be collected in drain collector  1020 . HME-absorbent media  1022  in drain collector  1020  may change color to indicate the presence of fluid in HME-absorbent media  1022 , signifying to a user that HME-absorbent media  1022  may be replaced. 
         [0073]    In an alternative embodiment of the present invention, illustrated in  FIGS. 14-16 , an adapter  1410  releasably connects nebulizer  601  to delivery system  604 . Adapter  1410  includes a body  1411  that defines an aerosol chamber  1415  into which an aerosol cloud  1403  of medication is directed after being generated by nebulizer  601 . Aerosol chamber  1415  includes an opening/passageway  1416  into and through which aerosol cloud  1403  travels to mix with breathing gas from delivery system  604 . Aerosolized cloud  1403  is represented by a broken arrow in  FIG. 16  as medication flows through passageway  1416  to be entrained with the breathing gas from delivery system  604 . 
         [0074]    Aerosol chamber  1415  is generally bifurcated into two separate pockets  1417  that are separated by a sloped baffle  1418 . Opening/passageway  1416  extends vertically through baffle  1418  and provides fluid communication between aerosol chamber  1415  and a through-passage  1420 . Pockets  1417  act as a reservoir for residual condensation from aerosol cloud  1403 , as well as from any of the heated and humidified breathing gas that may have traveled upward through opening/passageway  1416  and into chamber  1415 . Condensed liquid is retained in pockets  1417  and is not delivered to the patient. In order to drain liquid from pockets  1417 , adapted  1410  may be removed from nebulizer  601  and up-ended so that the fluid drains from adapter  1410 . 
         [0075]    Body  1411  also includes through-passage  1420  that extends through body  1411  from a breathing gas inlet end  1422  that is coupled to delivery system  604  to a breathing gas outlet end  1424  that is coupled to nasal cannula  606 . As shown in  FIG. 16 , breathing gas outlet end  1424  has a diameter “D.” 
         [0076]    Breathing gas generated by delivery system  604  is represented by solid arrows in through-passage  1420 . Passageway  1416  provides fluid communication between aerosol chamber  1415  and through-passage  1420  such that opening/passageway  1416  forms an opening between breathing gas inlet end  1422  and breathing gas outlet end  1424 . 
         [0077]    The passage of the breathing gas through through-passage  1420  generates a Venturi effect that draws aerosol cloud  1403  through opening/passageway  1416  and into through-passage  1420 , where the medication in aerosol cloud  1403  mixes with the breathing gas, as indicated by both the broken arrows (aerosolized medication) and solid arrows (breathing gas) at breathing gas outlet end  1424  of body  1411 . Thus, the medication becomes entrained within the breathing gas. 
         [0078]    An exemplary nasal cannula  1706  for use with adapter  1410  is illustrated in  FIG. 17 . Nasal cannula  1706  is releasably coupled to adapter  1410  to form a breathing gas delivery system  1700 . System  1700  may be used to deliver medication from nebulizer  601  to a patient. 
         [0079]    For neonatal use, nasal cannula  1706  may have an overall length of about 4½ inches (about 11.4 cm). This length is shorter than prior art neonatal cannulae, which typically have an overall length of about 13 inches (about 33 cm). The shorter length of cannula  1706  provides for delivery of heated and humidified breathing gas and aerosol mist with minimal loss of temperature and resulting condensation. The length of nasal cannula  1706  also allows a caregiver to hold both the patient and system  1700  during treatment of the patient. However, it will be understood by those of ordinary skill in the art that normal length cannulae may also be used for neonatal patients in conjunction with system  1700 . 
         [0080]    Further, the inner lumen  1708  of cannula  1706  has a diameter “D” that is about the same as the diameter “D” of breathing gas outlet end  1424 . The common diameter eliminates any dead spots between breathing gas outlet end  1424  and inner lumen  608  where condensate may form. 
         [0081]    Because of the short length of cannula  1706 , nebulizer system  600  may need to be held by a caregiver during treatment. For neonatal use, because only a small volume (about 1 to about 6 ml.) of medication is nebulized in nebulizer  601 , the duration of treatment is relatively short, and the caregiver can easily hold nebulizer system  600  for the duration of the treatment. 
         [0082]    In another alternative embodiment of a nebulizer system shown in  FIGS. 18-21 , instead of T-adapter  610 , an angled adapter  1810  is used. Angled adaptor  1810  includes a body  1811  defining an internal breathing gas mixing chamber  1815 . Angled adaptor includes a nebulizer coupling port  1814  that couples angled adapter  1810  to nebulizer  601 . Nebulizer coupling port  1814  provides for fluid communication between nebulizer outlet port  1809  and internal breathing gas mixing chamber  1815  such that aerosolized medication may be transmitted from nebulizer  601  to internal breathing gas mixing chamber  1815 . 
         [0083]    Angled adapter  1810  also includes a breathing gas inlet  1816  and a breathing gas outlet  1818 . Outlet  1818  extends outwardly from body  1811  and is adapted to couple to a breathing device, such as nasal cannula  606  (shown in  FIG. 7 ). Inlet  1816  extends from body  1811  and is adapted to couple to gas delivery system  604  (shown in  FIG. 7 ). Inlet  1816  and outlet  1818  are generally co-axial, with an opening, such as opening  1822 , separating inlet  1816  from outlet  1818  and communicating with chamber  1815 . Opening  1822  may be an oval about 0.2 inches by about 0.1 inches. For example, opening  1822  may be an oval that is 0.202 inches by 0.132 inches. 
         [0084]    As illustrated in  FIG. 18 , nebulizer coupling port  1814  of angled adaptor  1810  is angled with respect to a line perpendicular to the flow of the breathing gas through adaptor  1810 . In an exemplary embodiment, nebulizer coupling port  1814  may form an angle of approximately 15° with respect to a line perpendicular to the flow of gas. Nebulizer coupling port  1814  is angled to deliver a flow of aerosol in the direction of the flow of gas from breathing gas inlet  1816  to breathing gas outlet  1818  (i.e., toward outlet  1818 ). Angling nebulizer coupling port  1814  may be desirable in order to direct the flow of aerosol directly to the opening where it meets heated/humidified gas flow, thereby improving aerosolization and entrainment of the aerosol w/in the breathing gas flow. 
         [0085]    Angled adapter  1810  further includes a pressure-relief port  1819  that allows the relief of pressure away from the flow of breathing gas. Pressure-relief port  1819  is disposed at a side in angled adapter  1810 , and is in communication with chamber  1815 . Pressure-relief port  1819  may include a hydrophobic membrane  1820 . Hydrophobic membrane  1820  prevents build up of pressure within the chambers that may affect the aerosolization ability of the nebulizer. It has been discovered that increased pressure within the chamber  1815  may slow down or inhibit the production of aerosol by the nebulizer. The addition of hydrophobic membrane  1820  allows the venting of excess pressure from within the chamber  1815 , thereby allowing the nebulizer  601  to better produce aerosol, while also preventing the aerosol from escaping to atmosphere. Suitable materials for the hydrophobic membrane  1820  will be known to one of ordinary skill in the art from the description herein. 
         [0086]    In another alternative embodiment of a nebulizer system shown in  FIGS. 22-25 , instead of T-adapter  610 , an nebulizer cup adapter  2210  is used. Cup adaptor  2210  includes a body  2211  defining an internal breathing gas mixing chamber  2215 . Cup adaptor includes a nebulizer coupling port  2214  that couples cup adapter  2210  to nebulizer cup  2201 . Nebulizer coupling port  2214  provides for fluid communication between nebulizer outlet port  2209  and internal breathing gas mixing chamber  2215  such that aerosolized medication may be transmitted from nebulizer  2201  to internal breathing gas mixing chamber  2215 . 
         [0087]    Cup adapter  2210  also includes a breathing gas inlet  2216  and a breathing gas outlet  2218 . Outlet  2218  extends outwardly from body  2211  and is adapted to couple to a breathing device. Inlet  2216  extends from body  2211  and is adapted to couple to gas delivery system  604  (shown in  FIG. 7 ). Inlet  2216  and outlet  2218  are angled with respect to each other, with an opening separating inlet  2216  from outlet  2218  and communicating with chamber  2215 . As illustrated in  FIG. 22 , nebulizer coupling port  2214  of cup adaptor  2210  is coaxial with respect to outlet  2218 . 
         [0088]    As illustrated in  FIGS. 24 and 25 , outlet  2218  of cup adaptor  2210  may be adapted to be coupled to a nasal cannula  2206 . Nasal cannula  2206  may be a low diameter nasal cannula (as shown in  FIG. 24 ) or a high diameter nasal cannula (as shown in  FIG. 25 ). Suitable cannulas, and other breathing devices for coupling to outlet  2218  of cup adaptor  2210 , will be known to one of ordinary skill in the art from the description herein. 
         [0089]    Operation of the above alternative embodiment of the nebulizer system will be discussed with reference to  FIGS. 22-25 , as well as flow chart  2600 , illustrated in  FIG. 26 . While the nebulizer system with nebulizer cup adapter  2210  is discussed, those skilled in the art will recognize from the description herein that any alternative adaptor disclosed herein is also applicable. 
         [0090]    In STEP  2602 , a user (not shown) operates nebulizer cup  2201  to nebulize medication according to the operation of nebulizer  2201 . Operation of nebulizer cup  2201  to nebulize medication will be understood by one of ordinary skill in the art from the description herein. 
         [0091]    In STEP  2604 , the nebulized medication is entrained in a gas flow. In an exemplary embodiment, a flow of gas, which may be heated and humidified, is transmitted through cup adaptor  2210  from inlet  2216  to outlet  2218 . The nebulized medication from nebulizer  2201  is entrained in the gas flow. For example, the gas flow may draw the nebulized medication into the flow via the opening between inlet  2216  and outlet  2218 , i.e., due to a Venturi effect. For another example, the nebulized medication may be forced into the gas flow due to an air pressure difference between the nebulizer outlet port  2209  and the adaptor gas outlet  2218 . 
         [0092]    In STEP  2606 , the entrained nebulized medication is passed to a breathing device. In an exemplary embodiment, the entrained nebulized medication is passed to a nasal cannula  2206 . Suitable cannulas will be known to one of ordinary skill in the art from the description herein. 
         [0093]    It will be understood by one of ordinary skill in the art that the above operation of the nebulizer system may include any of the additional steps set forth with respect to nebulizer system  600 . 
         [0094]    Although the invention is illustrated and described herein with reference to specific embodiments, the invention is not intended to be limited to the details shown. Rather, various modifications may be made in the details within the scope and range of equivalents of the claims and without departing from the invention.