Patent Application
20120285452
This invention pertains to medical devices for the inhalation of drugs into the lungs.
In the field of respiratory devices, nebulizers are important devices used for the inhalation of drugs in the form of an aerosol. A nebulizer employs an apparatus that generates an aerosol or mist from a solution (usually an aqueous solution) or suspension of a drug. The mist may be an aerosolized suspension or an atomized suspension of drug, meaning micro-droplets suspended in air, medical oxygen, or other inhalable gas. The aerosol is conveyed to the mouth and/or nose of a patient and inhaled into the lungs. In some cases, the mist is conveyed to the lungs through a mouthpiece. In other cases, the nebulizer may be coupled to an inhalation mask.
Nebulizers operate by passing a stream of air or other suitable gas, such as medical oxygen, over or through a reservoir holding an aqueous solution of a drug for inhalation. In many cases, a stream of pressurized gas enters the nebulizer through a gas inlet and through a jet to produce a Venturi effect that draws a stream of the solution through a narrow passage or capillary from a pressure differential, whereby the liquid enters the jet and becomes atomized. Typically, a baffle is employed in the jet effluent that prevents large droplets from exiting the device, so that only aerosol micro-droplets of drug containing solution exit the device. An example of such a nebulizer is disclosed in U.S. Pat. No. 4,588,129. The aerosol is then inhaled by the patient. Typically, the aerosol production is continuous, so a vent is typically provided to ensure that the pressure differential created by the jet operates continuously and consistently.
The drug reservoir in nebulizers is usually a cone, cup, or bowl-shaped vessel into which a sterile aqueous solution of the drug is added. Accordingly, the orientation of the nebulizer is important, and the device must be kept approximately in an orientation such that the drug-containing solution stays in the reservoir where it can be aerosolized in the nebulizer. This restricts the range of motion available to the patient and nebulizer during use.
Typical drugs used with nebulizers are drugs for the treatment of asthma and obstructive pulmonary diseases, but other pulmonary and systematic medications may be administered by inhalation with nebulizers. For example, albuterol (called salbutamol in many countries), used for treating asthma and bronchospasm, may be administered as a nebulized solution. Another example is pentamidine, a drug used to treat Pneumocystis pneumonia (PCP).
Nebulizers are particularly useful for the administration of inhaled drugs to small children, elderly, unconscious, or disabled patients who cannot coordinate their breathing or take instruction on the use of coordinated inhalation devices, such as a metered dose inhaler. With a nebulizer, the dose of drug is administered to the patient over a period of several minutes, and possibly ten to twenty (or more) tidal or slow deep inhalations per minute, so breathing coordination is not required.
In the case of patients who cannot hold a mouthpiece in their mouth, an inhalation mask may be used with a nebulizer. This creates a complication in that the orientation of the mask and the nebulizer apparatus is important, to maintain the drug-containing solution in the reservoir for nebulization. Most nebulizer masks currently on the market have relatively inflexible connectors from the mask to the nebulizer apparatus and typically have a corrugated tube with a fixed 90° elbow for connection to a nebulizer. This requires that the patient inhale the mist while sitting straight in order to keep the nebulizer approximately vertical to avoid spilling the drug solution in the nebulizer or having the solution flow away from the capillary that carries the drug to the air-jet of the Venturi.
In one aspect, there is provided a swivel adapter for use as an airway with a nebulizer for inhaled drugs, wherein the adapter has a 90° elbow section, including a flanged joint comprising a frusto-spherical male section embedded in a matching frusto-spherical female section, that is pivotally flexible and can swivel over a broad range of angles and maintain a rigid airway at any angle. This apparatus with a ball-and-socket type of joint fits on the aerosol outlet of a nebulizer and allows a mouthpiece or mask to be adapted to the patient's most comfortable position while keeping the nebulizer in a roughly vertical orientation. In an embodiment, a method of using a nebulizer with a tube with a swivel adapter and a 90° elbow section, including a flanged joint, is provided. The adapter is used to convey an aerosolized drug from a nebulizer to the respiratory tract of a patient via inhalation through the nose and/or mouth.
In an embodiment, this invention discloses an adapter tube for use with a nebulizer for an inhalable drug, wherein the adapter comprises a pivotally flexible swivel joint that can swivel in any direction up to about 45° from its normal position, by use of a ball-and-socket type of flanged connector that provides a rigid airway regardless of the angle of use. The inhalable drug may be any drug intended for administration to the respiratory tract or lungs of a patient in need of such drug.
As used in the discussion herein, the term “proximal” means the section, orientation, or part closest to the face of a patient. The term “distal” means the section, orientation, or part closest to the nebulizer. Thus, the aerosol effluent from a nebulizer flows from the distal to the proximal end of the adapter in use.
Referring to the drawings, the embodiment in
As shown in the embodiment of
As shown in the embodiment of
Thus, in an embodiment, an adapter tube is provided defining an aerosol-conducting airway with a pivotally flexible swivel joint for the use with an inhalation mask or mouthpiece with a nebulizer for the administration of an inhaled drug to the respiratory tract of a patient, where the adapter tube includes a first 90° elbow tube member with an interior surface and outer surface, a distal leg and a proximal leg, wherein the distal leg and proximal leg are oriented at a 90° angle, and the distal leg comprises a cylindrical section adapted for fitting on to a nebulizer, and the proximal leg comprises a frusto-spherical convex outer surface; a second linear tubular member with an interior surface and outer surface, a distal section and a proximal section, wherein the distal section comprises a concave frusto-spherical flange on the interior surface of the distal section of said tubular member, and wherein the proximal section is adapted for fitting into an inhalation mask or mouthpiece; and the proximal outer-surface frusto-spherical section of the 90° elbow member fits inside the distal frusto-spherical flange of the linear tubular member to form a pivotally-flexible swivel joint providing a rigid pivotally flexible airway for conveying an aerosolized drug to the respiratory tract of the patient.
In an embodiment, the orientation of the pivotally-flexible ball-and-socket connection may be reversed; that is, the female frusto-spherical section (the “socket” component) may be on the elbow member corresponding to member 200, and the male frusto-spherical section (the nipple or “ball” component) may be on the tubular section corresponding to member 100.
The adapter as disclosed herein may optionally include vent openings, illustrated in the drawings as 140, that may be necessary to equalize the pressure within the device, so that the nebulizer jet creates the desired pressure differential (Venturi effect) to draw the drug-containing solution into the jet where it is nebulized. In the case of continuous nebulization, vents are required to equalize the pressure and carry the aerosol away from the patient. In other embodiments, for example with a breath-actuated nebulizer, no vent holes will be provided. In some embodiments, including that shown in
Thus, the adapter 10 can be used with a conventional continuous nebulizer, or with a breath-actuated nebulizer. In a conventional continuous nebulizer, a steady flow of aerosol is produced. In such devices, the mouthpiece is typically vented, keeping the pressure balanced in the nebulizer, but permitting aerosolized drug to escape from the device. With many drugs (for asthma therapy, for example) the escape and wasting of drug aerosol is not a problem, particularly if the drug is inexpensive and non-sensitizing.
Other vent configurations are also possible besides a type of configuration depicted as 140 in the Figures. For example, vent openings can be elsewhere on the adapter. In an embodiment, there may be vent openings within the ball-and-socket pivotally flexible joint.
An alternative embodiment 14 of the inventive adapter is shown in
In an alternative, the opposite arrangement to
In recent years, breath-actuated nebulizers have become available, for example the “AeroEclipse®” available in the United States from Monaghan Medical Corporation. These devices have a mechanism that prevents aerosolization within the device except when the patient is actually inhaling. There is no free vent allowing un-inhaled drug to escape during exhalation. Such devices are particularly useful where either the cost of the drug is very high or when the drug is sensitizing to caregivers (e.g. antibiotics), making wastage undesirable. Breath-actuated nebulizers are also useful where the dose of inhaled drug is critical, since without the wastage of a conventional nebulizer, the care-giver can be more certain of the amount of drug actually inhaled by the patient.
Also disclosed herein is a method of using a nebulizer with an adapter interposed between the nebulizer body and a mouthpiece or inhalation mask, allowing a degree of flexibility in the positioning of the device relative to the patient using the device. In an embodiment, this may provide a more comfortable position for the patient, since a nebulizer (as noted above), must typically be maintained in an approximately vertical orientation so that the drug-containing solution is properly oriented in the reservoir for nebulization. In most cases, nebulizers are cylindrical in shape and must be kept in an approximately vertical orientation in use. Thus, the pivotally flexible adapter may provide a more comfortable position for a patient. In another embodiment, the patient may be incompetent (unable to take instructions even to sit up) or unconscious. In such cases, in which an inhalation mask would normally be used, the inventive adapter gives caretakers enhanced flexibility in orienting the patient and/or the nebulizer for effective administration of the drug.
The adapter with an inhalation mask is shown in
As shown in
This application claims priority under 35 U.S.C. §119(e) to U.S. Provisional Patent Application No. 61/485,036, filed May 11, 2011, the contents of which are hereby incorporated by reference.
| Number | Date | Country | |
|---|---|---|---|
| 61485036 | May 2011 | US |
