U.S. patent application number 16/042472 was filed with the patent office on 2019-02-07 for medical nebulizer for fast drug delivery.
The applicant listed for this patent is TELEFLEX MEDICAL INCORPORATED. Invention is credited to Daniel P. DWYER, Erin GRAHAM.
Application Number | 20190038852 16/042472 |
Document ID | / |
Family ID | 65231042 |
Filed Date | 2019-02-07 |
United States Patent
Application |
20190038852 |
Kind Code |
A1 |
DWYER; Daniel P. ; et
al. |
February 7, 2019 |
MEDICAL NEBULIZER FOR FAST DRUG DELIVERY
Abstract
A nebulizer is provided to atomize a liquid medication for rapid
delivery of an aerosol spray to a user via inhalation. The
nebulizer includes a jar having a compressed gas passage. A jet
cooperates with the jar and has a jet orifice through which the
liquid medication and the compressed gas are discharged to form an
aerosol flow. The cap is connected to the jar to define an inner
chamber. The cap includes an entrainment port for ambient room air,
and a chimney in fluid communication with the entrainment port and
the inner chamber. A deflector base having an impingement member is
located adjacent to the entrainment chimney and is spaced below an
opening thereof by a predetermined distance to provide a flow of
the ambient room air to be entrained in the aerosol flow in order
to enhance nebulization speed while maintaining a desired aerosol
particle size.
Inventors: |
DWYER; Daniel P.; (Cary,
NC) ; GRAHAM; Erin; (Chapel Hill, NC) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
TELEFLEX MEDICAL INCORPORATED |
Morrisville |
NC |
US |
|
|
Family ID: |
65231042 |
Appl. No.: |
16/042472 |
Filed: |
July 23, 2018 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
62540225 |
Aug 2, 2017 |
|
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|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61M 11/06 20130101;
A61M 15/0086 20130101; A61M 11/04 20130101; A61M 15/002 20140204;
A61M 11/001 20140204; A61M 11/002 20140204 |
International
Class: |
A61M 11/04 20060101
A61M011/04; A61M 11/00 20060101 A61M011/00; A61M 15/00 20060101
A61M015/00 |
Claims
1. A nebulizer configured to atomize a liquid medication for
inhalation by a user, the nebulizer comprising: a jar defining a
reservoir configured to hold the liquid medication, the jar
defining a compressed gas passage configured to receive a flow of
compressed gas; the compressed gas passage terminating in a jet
orifice defined by the jar through which the liquid medication and
the compressed gas are discharged through to form an aerosol flow
having the liquid medication entrained in the compressed gas; a cap
connected to the jar to define an inner chamber inside the
nebulizer, the cap comprising: an entrainment port configured to
provide an inlet for a flow of ambient room air; an entrainment
chimney having a first opening in fluid communication with the
entrainment port and a second opening in fluid communication with
the inner chamber, the entrainment port and entrainment chimney
together defining an entrainment pathway for the ambient room air;
a deflector base spaced below the second opening of the entrainment
chimney by a predetermined distance to define at least one
entrainment vent configured to provide a flow of the ambient room
air into the inner chamber for enhancing nebulization speed of the
nebulizer, such that the at least one entrainment vent is
configured to rapidly entrain the ambient room air into the aerosol
flow to form an ambient air-entrained aerosol spray for inhalation
by the user.
2. The nebulizer of claim 1, wherein the at least one entrainment
vent has a height greater than 0 inches and less than or equal to
about 0.45 inches.
3. The nebulizer of claim 2, wherein the at least one entrainment
vent has a height about 0.12 inches.
4. The nebulizer of claim 1, further comprising a plurality of
support fins connecting the deflector base to the entrainment
chimney.
5. The nebulizer of claim 4, wherein each of the at least one
entrainment vent is provided between adjacent support fins.
6. The nebulizer of claim 1, wherein the cap further comprises an
impingement member extending from the deflector base and configured
to further atomize particles in the aerosol flow and to prevent
exhalation from the user from driving liquid medication out of the
nebulizer through the entrainment pathway and out of the
entrainment port.
7. The nebulizer of claim 6, wherein the impingement member
includes a hemispherical surface.
8. The nebulizer of claim 6, wherein a center of the impingement
member is aligned with an axis of the jet orifice.
9. The nebulizer of claim 1, wherein a flow axis of the entrainment
port is substantially perpendicular to a flow axis of the
entrainment chimney.
10. The nebulizer of claim 1, wherein the entrainment port is
further configured to provide an inhalation pathway.
11. The nebulizer of claim 10, wherein the entrainment port is
further configured to provide an exhalation pathway.
12. The nebulizer of claim 1, wherein the cap further comprises an
aerosol flow outlet port for outputting the aerosol flow to the
user, the aerosol flow outlet port configured to connect to a user
interface.
13. The nebulizer of claim 12, wherein the aerosol flow outlet port
is configured to detachably connect to the user interface.
14. The nebulizer of claim 12, wherein the user interface is a
mouthpiece or a breathing mask.
15. The nebulizer of claim 12, wherein the aerosol flow outlet port
further includes a saliva catch configured to capture saliva from
the mouth of the user during inhalation and exhalation.
16. The nebulizer of claim 1, wherein the cap is detachably
connected to the jar.
17. The nebulizer of claim 1, wherein the deflector base comprises
a disk.
18. The nebulizer of claim 1, wherein the entrainment port is
configured to connect to a PEEP valve or a filter.
19. The nebulizer of claim 1, wherein the entrainment chimney
includes a longitudinal axis aligned with a longitudinal axis of
the jet orifice.
20. The nebulizer of claim 1, wherein the entrainment chimney is
generally tubular.
21. The nebulizer of claim 1, wherein particles in the aerosol flow
have an aerodynamic diameter between 1 and 5 micrometers for
targeted lower airway deposition.
22. The nebulizer of claim 1, wherein the nebulizer is configured
to continuously nebulize the liquid medication during inhalation
and exhalation of the user.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to U.S. Provisional Patent
Application No. 62/540,225 filed Aug. 2, 2017, the content of which
is incorporated herein by reference in its entirety.
FIELD OF THE DISCLOSURE
[0002] The present disclosure relates generally to an aerosol
delivery device, and more particularly, to a medical nebulizer
configured to rapidly nebulize liquid medicament into an aerosol
spray for inhalation by a user.
BACKGROUND
[0003] Medical nebulizers are used to aerosolize a liquid
medicament for inhalation by a user. The aerosol is produced via
the nebulization process by dispersing fine droplets of the liquid
medicament into a flow stream of gas. The nebulized medicament can
then be delivered into the airways of the user's lungs, which can
be very useful in medical treatments due to the high permeability
of the lungs. Medications inhaled into the lungs are therefore
readily able to enter the user's bloodstream for dispersion
throughout the rest of the user's body.
[0004] The medicated aerosol particles produced from a medical
nebulizer must be sufficiently sized in order to provide safe and
effective treatment to a user. Aerosol particles having an
aerodynamic diameter between 1 and 5 micrometers are typically
considered inhalable by a user. Many conventional medical
nebulizers produce aerosol particles having an aerodynamic diameter
that is less than 2 micrometers, which results in the deposition of
the particles within the alveoli of the user's lungs. Other
conventional medical nebulizers produce aerosol particles having an
aerodynamic diameter that is over 5 micrometers, which results in
the deposition of particles on the surface of the upper respiratory
airways instead of reaching the lungs. The ideal respirable
particle size range of aerosol particles is 1 micrometer to 5
micrometers in order to ensure deposition of medicated aerosol
particles within the lower airways of a user upon inhalation.
[0005] A fast nebulization rate is often desired in order to yield
a short overall treatment time for the user and maximize clinician
workflow. However, conventional nebulizers that rapidly produce
aerosol fail to maintain a beneficial particle size distribution of
the aerosolized medicament. This is because increasing the
nebulization rate for such conventional nebulizers results in
aerosol particles that are often too large to be safely and
effectively inhaled by a user. Large variances exist in the
nebulization rate of conventional nebulizers, as well as the
corresponding respirable size of the aerosol particles produced by
conventional nebulizers.
[0006] Moreover, while some conventional nebulizers entrain room
air during the nebulization process, such entrainment requires
effort by the user to breath in the room air through the nebulizer.
Relying on user effort to enhance the flow of air into the
nebulizer can have varying levels of effectiveness since such user
effort is dependent on the health condition of the user, including
the user's lung capacity and stamina. Thus, users having poor
health are often not able to effectively entrain a sufficient
amount of room air into such conventional nebulizers. Additionally,
users who rely on such conventional nebulizers that entrain room
air during the nebulization process often experience deleterious
effects, such as degrading the liquid consumption rate in the jar
of the nebulizer, as well as spitting of the liquid medicament onto
the user's hands and face via escape through an entrainment flow
path.
[0007] Accordingly, there is a need for an improved nebulizer with
a fast nebulization delivery rate for reducing user treatment time,
thus helping user compliance and also enhancing clinician workflow
efficiency. It is further desirable to quickly nebulize aerosol
from a nebulizer while maintaining a beneficial aerosol particle
size distribution between 1 and 5 micrometers for targeted lower
airway deposition. Furthermore, there is a need for a medical
nebulizer that doesn't cause deleterious effects, such as degrading
the liquid consumption rate in the jar and spraying liquid
medication out of the nebulizer through the entrainment flow
path.
SUMMARY OF THE DISCLOSURE
[0008] The foregoing needs are met, to a great extent, by the
present disclosure, wherein a nebulizer is configured to atomize a
liquid medication for inhalation by a user. The nebulizer may
comprise a jar defining a reservoir configured to hold the liquid
medication, the jar defining a compressed gas passage configured to
receive a flow of compressed gas. The compressed gas passage
terminates in a jet orifice defined by the jar and the jet through
which the liquid medication and the compressed gas are discharged
to form an aerosol flow having the liquid medication entrained in
the compressed gas. A cap is connected to the jar to define an
inner chamber inside the nebulizer. The cap may comprise an
entrainment port configured to provide an inlet for a flow of
ambient room air; an entrainment chimney having a first opening in
fluid communication with the entrainment port and a second opening
in fluid communication with the inner chamber, the entrainment port
and entrainment chimney together defining an entrainment pathway
for the ambient room air; and a deflector base spaced below the
second opening of the entrainment chimney by a predetermined
distance to define at least one entrainment vent configured to
provide a flow of the ambient room air into the inner chamber for
enhancing nebulization speed of the nebulizer, such that the at
least one entrainment vent is configured to rapidly entrain the
ambient room air into the aerosol flow to form an ambient
air-entrained aerosol spray for inhalation by the user.
[0009] According to another aspect of the disclosure, the cap may
further comprise an impingement member extending from the deflector
base and configured to further atomize particles in the aerosol
flow and to prevent exhalation from the user from driving liquid
medication out of the nebulizer through the entrainment pathway and
out of the entrainment port.
[0010] According to another aspect of the disclosure, the at least
one entrainment vent has a height greater than 0 inches and less
than or equal to about 0.45 inches.
[0011] According to another aspect of the disclosure, the at least
one entrainment vent has a height about 0.12 inches.
[0012] According to another aspect of the disclosure, a plurality
of support fins connect the deflector base to the entrainment
chimney.
[0013] According to another aspect of the disclosure, each of the
at least one entrainment vents is provided between adjacent support
fins.
[0014] According to another aspect of the disclosure, the
impingement member includes a hemispherical surface.
[0015] According to another aspect of the disclosure, a center of
the impingement member is aligned with an axis of the jet
orifice.
[0016] According to another aspect of the disclosure, a flow axis
of the entrainment port is substantially perpendicular to a flow
axis of the entrainment chimney.
[0017] According to another aspect of the disclosure, the
entrainment port is further configured to provide an inhalation
pathway.
[0018] According to another aspect of the disclosure, the
entrainment port is further configured to provide an exhalation
pathway.
[0019] According to another aspect of the disclosure, the cap may
further comprise an aerosol flow outlet port for outputting the
aerosol flow to the user, the aerosol flow outlet port configured
to connect to a user interface.
[0020] According to another aspect of the disclosure, the aerosol
flow outlet port is configured to detachably connect to the user
interface.
[0021] According to another aspect of the disclosure, the user
interface is a mouthpiece or a breathing mask.
[0022] According to another aspect of the disclosure, the aerosol
flow outlet port further includes a saliva catch configured to
capture saliva from the mouth of the user during inhalation and
exhalation.
[0023] According to another aspect of the disclosure, the cap is
detachably connected to the jar.
[0024] According to another aspect of the disclosure, the deflector
base may comprise a disk.
[0025] According to another aspect of the disclosure, the
entrainment port is configured to connect to a PEEP valve or a
filter.
[0026] According to another aspect of the disclosure, the
entrainment chimney includes a longitudinal axis aligned with a
longitudinal axis of the jet orifice.
[0027] According to another aspect of the disclosure, the
entrainment chimney is generally tubular.
[0028] According to another aspect of the disclosure, particles in
the aerosol flow have an aerodynamic diameter between 1 and 5
micrometers for targeted lower airway deposition.
[0029] According to another aspect of the disclosure, the nebulizer
is configured to continuously nebulize the liquid medication during
inhalation and exhalation of the user.
[0030] There has thus been outlined certain embodiments of the
disclosure in order that the detailed description thereof herein
may be better understood, and in order that the present
contribution to the art may be better appreciated. There are
additional embodiments of the disclosure that will be described
below and which form the subject matter of the claims appended
hereto.
[0031] In this respect, before explaining at least one embodiment
of the disclosure in detail, it is to be understood that the
disclosure is not limited in its application to the details of
construction and to the arrangements of the components set forth in
the following description or illustrated in the drawings. The
disclosure is capable of embodiments in addition to those described
and of being practiced and carried out in various ways. Also, it is
to be understood that the phraseology and terminology employed
herein, as well as the abstract, are for the purpose of description
and should not be regarded as limiting.
[0032] As such, those skilled in the art will appreciate that the
conception upon which this disclosure is based may readily be
utilized as a basis for the designing of other structures, methods
and systems for carrying out the several purposes of the present
disclosure. It is important, therefore, that the claims be regarded
as including such equivalent constructions insofar as they do not
depart from the spirit and scope of the present disclosure.
BRIEF DESCRIPTION OF THE DRAWINGS
[0033] FIG. 1 is a perspective view illustrating an apparatus in
accordance with one or more embodiments of the present
disclosure.
[0034] FIG. 2 is a side elevation view illustrating the apparatus
of FIG. 1.
[0035] FIG. 3 is a cross-sectional view illustrating the apparatus
of FIG. 2 in one or more additional embodiments of the present
disclosure.
[0036] FIG. 3a is an enlarged view of a section of the apparatus
shown in FIG. 3.
[0037] FIG. 4 is a cross-sectional view illustrating the apparatus
of FIG. 2 along lines 4-4.
[0038] FIG. 5 is a cross-sectional view illustrating the apparatus
of FIG. 2 along lines 5-5.
DETAILED DESCRIPTION
[0039] The disclosure will now be described with reference to the
drawing figures, in which like parts are referred to with like
reference numerals throughout. One or more embodiments in
accordance with the present disclosure provide a breath enhanced
medical nebulizer 10 for fast drug delivery, as shown throughout
FIGS. 1-5. The nebulizer 10 is configured to aerosolize a liquid
medication into an aerosol spray or mist for safe and effective
inhalation by a user, such as a patient. The nebulizer 10 comprises
a jar 20 configured to hold the liquid medication, a jet 30
configured to cooperate with the jar 20, and a cap 40 configured to
detachably connect to the jar 20.
[0040] The jar 20 includes an outer surrounding wall 21 and defines
a reservoir 22 configured to hold a liquid 24, such as a liquid
medication. The jar further defines a compressed gas passage 26
configured to receive a flow of compressed gas. More particularly,
the jar 20 comprises a compressed gas nozzle 23 having a first
portion extending outside the surrounding wall 21 and a second
portion extending into the reservoir 22. The compressed gas nozzle
23 comprises the compressed gas passage 26, which has a gas inlet
27 and a gas outlet 28. The jet 30 is detachably connected to the
jar 20, and may further be configured to detachably connect to the
second portion of the compressed gas nozzle 23 extending into the
reservoir 22 by an interference fit. Additionally, the compressed
gas nozzle 23 and the jet 30 may both be generally tubular in
shape.
[0041] The jet 30 is configured to cooperate with the jar 20 such
that a gap defining a fluid flow passage 34 is disposed between the
jet 30 and the second portion of the compressed gas nozzle 23. The
jet 30 includes a jet wall forming an internal cavity therein that
is configured to receive the second portion of the compressed gas
nozzle 23 extending into the reservoir 22. The fluid flow passage
34 comprises a vertical flow section and a horizontal flow section.
The first portion of the compressed gas nozzle 23 having the
compressed gas inlet 27 is configured to connect to a pressurized
gas source or a gas supply tubing. The compressed gas passage 26
terminates in the gas outlet 28 such that an output of compressed
gas is dispersed having an exit plane disposed substantially
perpendicular to the fluid flow passage 34.
[0042] The jet 30 further comprises a jet orifice 32 located at an
end of the internal cavity of the jet and provided in fluid
communication with both the compressed gas passage 26 and the fluid
flow passage 34. More particularly, the gas outlet 28 of the
compressed gas passage 26 terminates in the jet orifice 32 through
which the liquid medication and the compressed gas are discharged
through to form an initial aerosol flow having the liquid
medication entrained in the compressed gas.
[0043] The compressed gas outlet 28 and jet orifice 32 are
configured to control the pressure-flow relationship of the
nebulizer 10 by creating a venturi effect that causes a pressure
drop of the compressed gas flowing through the gas outlet 28 and
the jet orifice 32. Thus, during operation of the nebulizer 10, the
compressed gas exits the gas outlet 28 and enters the jet orifice
32, creating a localized vacuum that draws liquid 24 from the fluid
reservoir 22 into the fluid flow passage 34 due to negative
pressure generated within the flow passage 34. The diameter of the
gas outlet 28 may be approximately 0.010 to 0.025 inches. The jet
orifice 32 is configured to ensure that a sufficient vacuum is
maintained so that the liquid medication 24 drawn into the fluid
flow passage 34 is further drawn through the jet orifice 32 and
fully mixed with the compressed gas that is received from the gas
outlet 28. This process atomizes the liquid medication, resulting
in an aerosol flow being discharged from the jet orifice 32. The
aerosol flow is subsequently entrained with a flow of ambient room
air, resulting in an ambient room air-entrained aerosol spray for
inhalation by the user, as will be further discussed below. In some
implementations, liquid particles in the aerosol flow may be
further atomized by an impingement member either before, or
contemporaneously with, entrainment of a flow of ambient room air,
as will also be further discussed below
[0044] The cap 40 is connected to the jar 20 to define an inner
chamber 42 inside the nebulizer. The cap 40 and jar 20 may be
configured to detachably connect to each other. In some
implementations, the cap 40 includes a cap fastener 41 configured
to securely engage a jar fastener 29 of the jar 20. The cap
fastener 41 may include cap threads and the jar fastener 29 may
include jar threads that engage the cap threads to provide a
threaded engagement of the cap 40 to the jar 20. For instance, a
proximal end of the surrounding wall 21 of the jar 20 may include
jar threads to threadedly engage corresponding cap threads provided
on an annular connection collar 43 extending from a distal end of
the cap 40. In other implementations, the cap fastener 41 may
include a flange and the jar fastener 29 may include a protrusion,
or vice versa, such that the flange and protrusion are configured
to matingly engage each other in order to provide a snap-fit
securement of the cap 40 to the jar 20.
[0045] The cap comprises an entrainment port 44 extending into the
inner chamber 42 and configured to act as an inlet for the flow of
ambient room air; an entrainment chimney 46 located within the
inner chamber 42 and configured to provide an entrainment pathway
for the flow of ambient room air to be entrained in the aerosol
flow; and an aerosol port 56 configured to removably attach to a
user interface, such as a mouthpiece or mask, for delivering the
ambient room air-entrained aerosol spray to the user. The chimney
includes a first opening 46A in fluid communication with the
entrainment port 44 and a second opening 46B in fluid communication
with the inner chamber 42. Each of the entrainment port 44, the
entrainment chimney 46, and the aerosol port 56, may be generally
tubular.
[0046] The entrainment port 44 is configured to serve as an inlet
port for the flow of ambient room air into the inner chamber 42, as
well as an outlet port for discharging an exhalation flow of the
user. In some implementations, a secondary flow path separate from
the entrainment flow path may be included so that exhalation by the
user can flow therethrough either due to a lower resistance to
exhalation flow or due to a valve element in communication with the
secondary flow path. Moreover, the entrainment port 44 is
configured to detachably connect to various breathing circuit
accessories, such as PEEP valves and filters. More particularly, an
outer diameter of the entrainment port 44 may be approximately 15
mm in order to accept such breathing circuit accessories.
[0047] The cap 40 also comprises a deflector base 50, such as a
disk or baffle, spaced below the second opening 46B of the
entrainment chimney 46. The deflector base 50 is supported by at
least one support fin, and may be supported by a plurality of
support fins, such as three support fins 48A, 48B, 48C, as
illustrated in FIGS. 4 and 5. Each support fin 48A, 48B, 48C may
extend from the entrainment chimney 46, a surrounding wall of the
cap 40, or a combination of both. In some implementations, the
plurality of support fins 48A, 48B, 48C may be equally spaced apart
radially around a circumference of the entrainment chimney 46 or
the surrounding wall of the cap 40.
[0048] The cap 40 further comprises an impingement member 52
extending from the center of the deflector base 50 in a direction
toward the jet orifice 32. The impingement member 52 may be
dome-shaped, and is configured to prevent a user's exhalation from
driving liquid medication out of the nebulizer through the
entrainment chimney 46 by partially blocking the second opening
46B. The dome may have a radius of approximately 0.125 inches. The
apex of the dome may be spaced a predetermined distance D away from
the deflector base 50, where D may be approximately 0.18 inches.
This arrangement helps prevent liquid from spraying out of the
nebulizer via the entrainment flow path and onto the user's hands
or face. Additionally, a longitudinal axis of the entrainment port
44 is arranged substantially perpendicular to a longitudinal axis
of the entrainment chimney 46 to provide additional protection from
deleterious effects, such as spitting liquid out of the nebulizer
via the entrainment flow path, by re-directing the user's
exhalation through the entrainment port 44 and away from the
user.
[0049] As previously described, the liquid medication 24 and the
compressed gas form an aerosol flow as they are dispersed from the
jet orifice 32 during operation of the nebulizer. The jet orifice
32 is adjacent to and aligned with the center of the impingement
member 52 to allow liquid particles in the aerosol flow to impinge
the surface of the impingement member 52, thereby further atomizing
the particles in the aerosol flow. The jet orifice 32 and the
center of the impingement member 52 may be spaced apart by a
predetermined distance G, where G may be approximately 0.010
inches, such that aerosol flow discharged from the jet orifice 32
strikes the curved surface of the dome-shaped impingement member,
thus forming an aerosol flow with respirable aerosol particles
having an aerodynamic diameter between 1 and 5 micrometers for
targeted lower airway deposition in a user's lungs.
[0050] At least one entrainment vent 54 is spaced between the
deflector base 50 and the second opening 46B of the entrainment
chimney 46. In implementations having a plurality of support fins
48A, 48B, 48C, a plurality of entrainment vents 54 are
correspondingly provided between the deflector base 50 and the
second opening 46B of the entrainment chimney 46, such that each
entrainment vent 54 is disposed between adjacent support fins. Each
entrainment vent 54 is configured to rapidly entrain the ambient
room air supplied through the entrainment chimney 46 into the
aerosol flow to form the ambient air-entrained aerosol spray for
inhalation by the user.
[0051] During use, compressed gas at high pressure enters the
nebulizer 10 at the compressed gas inlet 27 and travels into the
compressed gas passage 26. The compressed gas flowing through the
gas passage 26 is converted to a high-speed gas as it flows through
the gas outlet 28. This high-speed gas passes through a portion of
the fluid flow passage 34 and into the jet orifice 32, thus
creating a vacuum that draws the liquid medication 24 from the
reservoir 22 through the fluid flow passage 34 and into the jet
orifice 32, where the liquid medication mixes with the compressed
gas. As previously described, this combined flow of liquid
medicament 24 and compressed gas is then discharged out of the jet
orifice 32 as the aerosol flow. Replacement liquid medicament 22 is
continuously drawn up through the fluid flow passage 34 from the
reservoir 22 as liquid medicament is aerosolized by the
high-pressure gas through the jet orifice 32. Contact of the
aerosol flow with the impingement member 52 further atomizes
particles in the aerosol flow within the inner chamber 42.
[0052] Additionally, the venturi effect created at the gas outlet
28 and the jet orifice 32 also pulls the external ambient room air
into the inner chamber 42 via the entrainment pathway defined by
the entrainment port 44 and the entrainment chimney 46. This
ambient room air is drawn into the inner chamber 42 of the
nebulizer for entrainment into the aerosol flow in order to
increase the nebulization speed, and therefore enhance treatment
time or speed of delivery of the resulting ambient air-entrained
aerosol spray to a user. The ambient room air is automatically
drawn into the inner chamber 42 through the entrainment flow
pathway of the entrainment port 44 and the entrainment chimney 46
due to the pressure differential created between the inner chamber
42 of the nebulizer and the external ambient room air caused by the
venturi effect. Accordingly, the user does not have to expend
additional effort while breathing to enhance the flow of ambient
room air into the nebulizer 10.
[0053] Each entrainment vent 54 is located near the jet orifice 32
and is dimensioned such that the aforementioned venturi effect
automatically pulls in a flow of the ambient room air to be
entrained in the aerosol flow for enhancing the overall rate of
nebulization. If the entrainment vent 54 is too large, then the
ambient room air will not be automatically pulled into the
nebulizer via the venturi effect. Conversely, if the entrainment
vent 54 is too small, exhalation by the user could be difficult,
and a deleterious accumulation of fluid may occur which could
result in the loss of medication. The deflector base 50 is
therefore spaced from the second opening 46B of the entrainment
chimney 46 by a predetermined distance H in order to increase the
nebulization speed, while also resulting in room air-entrained
aerosol particles having an aerodynamic diameter between 1 and 5
micrometers. To ensure particles in the room air-entrained aerosol
spray have an aerodynamic diameter between 1 and 5 micrometers, the
height H of each entrainment vent is greater than 0 inches and less
than or equal to about 0.45 inches. In some implementations, each
entrainment vent 54 has a height H of approximately 0.12 inches in
order to ensure that the ambient room air is rapidly entrained due
to the venturi created from the jar, while still resulting in
particles of the aerosol spray having an aerodynamic diameter
between 1 and 5 micrometers. To further ensure that the ambient
room air is rapidly entrained into the aerosol flow, the second
opening 46B of the entrainment chimney 46 may have diameter of
about 0.59 inches and a cross-sectional area of approximately 0.27
square inches, and the entrainment port 44 may have a diameter of
about 0.52 inches and a cross-sectional area of approximately 0.21
square inches.
[0054] Each entrainment vent 54 is disposed adjacent to the
impingement member 52 and open in a direction transverse to the
longitudinal axis of the entrainment chimney 46. This allows the
ambient room air to be entrained in the aerosol flow produced at
the impingement member and also to be directed toward an opening
56A at the outer periphery of the inner chamber 42 for rapid
delivery through the aerosol port 56 for inhalation by the user. In
some implementations in which the nebulizer is configured to be
used continuously during both inhalation and exhalation by the
user, the aerosol port 56 may include a saliva catch 58 located
therein and configured to collect any saliva emanating from the
user's mouth during inhalation or exhalation in order to prevent
contaminating the liquid medicine 24 held in the reservoir 22 of
the nebulizer.
[0055] Entraining the ambient room air into the aerosol flow within
the inner chamber 42 of the nebulizer increases the speed of
delivery of the resulting ambient room air-entrained aerosol spray
discharged through the aerosol port 56 to the user. More
particularly, entrainment of ambient room air into the aerosol flow
formed at the impingement member 52 causes the resulting room
air-entrained aerosol spray to accelerate toward the aerosol port
56 for inhalation by the user, thus rapidly delivering respirable
medication to the user. Additionally, the ambient room air is
entrained into the aerosol flow without requiring user effort to
enhance the flow of air into the nebulizer.
[0056] As previously described, the resultant aerodynamic diameter
of the room air-entrained aerosol particles that are discharged
through the aerosol port 56 to the user is between 1 and 5
micrometers, which is the ideal respirable range for targeted lower
airway deposition in the lungs. While entrainment of the ambient
room air into the aerosol flow increases the speed of delivery of
the resulting room air-entrained aerosol spray through the aerosol
port 56 for inhalation by the user, the location of the deflector
base 50 relative to the second opening 46B of the entrainment
chimney 46 and location of the impingement member 52 relative to
the jet orifice 32 prevent the aerosol spray from entering the
entrainment flow path and spraying out of the entrainment port 44
of the nebulizer. The ability of the nebulizer 10 to rapidly
nebulize liquid medication while still maintaining a beneficial
particle size distribution can help lower the treatment time for a
user and thus also lessen the amount of time that a caregiver
spends with the user during treatments, thereby improving clinical
workflow efficiency. A quicker treatment time also results in
better user compliance since less time is needed to hold the
nebulizer 10 during use.
[0057] The many features and advantages of the disclosure are
apparent from the detailed specification, and thus, it is intended
by the appended claims to cover all such features and advantages of
the disclosure which fall within the true spirit and scope of the
disclosure. The recitation of numerical ranges by endpoints
includes all numbers and sub-ranges within and bounding that range
(e.g., 1 to 4 includes 1, 1.5, 1.75, 2, 2.3, 2.6, 2.9, etc. and 1
to 1.5, 1 to 2, 1 to 3, 2 to 3.5, 2 to 4, 3 to 4, etc.). Further,
since numerous modifications and variations will readily occur to
those skilled in the art, it is not desired to limit the disclosure
to the exact construction and operation illustrated and described,
and accordingly, all suitable modifications and equivalents may be
resorted to, falling within the scope of the disclosure.
* * * * *