U.S. patent application number 10/675198 was filed with the patent office on 2004-04-08 for nasal mask.
This patent application is currently assigned to Fisher & Paykel Healthcare Limited. Invention is credited to Gradon, Lewis George, Haycock, Mark Joseph, McAuley, Alastair Edwin, Nightingale, Chris Earl, Smith, Nicholas Charles Alan.
Application Number | 20040065327 10/675198 |
Document ID | / |
Family ID | 27567217 |
Filed Date | 2004-04-08 |
United States Patent
Application |
20040065327 |
Kind Code |
A1 |
Gradon, Lewis George ; et
al. |
April 8, 2004 |
Nasal mask
Abstract
A CPAP system is described for improved respiratory therapy of
patients. In particular a patient interface is disclosed with an
outlet vent with lower noise levels and more diffused outlet flow
over prior art outlet vents. The outlet vent includes a main vent
which is diffused and muffled and a higher resistance vent provided
in case the main vent is blocked. The outlet vent is removable for
easy maintenance and provides indication to the user when
maintenance is required. The outlet vent described may be used on
nasal masks, mouthpieces and patient interfaces generally.
Inventors: |
Gradon, Lewis George;
(Auckland, NZ) ; Smith, Nicholas Charles Alan;
(Auckland, NZ) ; McAuley, Alastair Edwin;
(Auckland, NZ) ; Haycock, Mark Joseph; (Auckland,
NZ) ; Nightingale, Chris Earl; (Auckland,
NZ) |
Correspondence
Address: |
TREXLER, BUSHNELL, GIANGIORGI,
BLACKSTONE & MARR, LTD.
105 WEST ADAMS STREET
SUITE 3600
CHICAGO
IL
60603
US
|
Assignee: |
Fisher & Paykel Healthcare
Limited
Auckland
NZ
|
Family ID: |
27567217 |
Appl. No.: |
10/675198 |
Filed: |
September 30, 2003 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10675198 |
Sep 30, 2003 |
|
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09881394 |
Jun 14, 2001 |
|
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6662803 |
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Current U.S.
Class: |
128/205.25 ;
128/206.12; 128/206.21 |
Current CPC
Class: |
A61M 16/109 20140204;
A61M 16/0069 20140204; A61M 16/0616 20140204; A61M 16/0638
20140204; A61M 16/1095 20140204; A61M 16/08 20130101; A61M 16/06
20130101; A61M 16/1065 20140204; A61M 16/0666 20130101; A61M
16/0683 20130101; A61M 2205/42 20130101; A61M 2016/0039 20130101;
A61M 16/1045 20130101; A61M 16/16 20130101; A61M 16/0066
20130101 |
Class at
Publication: |
128/205.25 ;
128/206.12; 128/206.21 |
International
Class: |
A62B 018/02; A62B
018/08 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 16, 2000 |
NZ |
508218 |
Jun 14, 2000 |
NZ |
505154 |
Jun 14, 2000 |
NZ |
505155 |
Dec 20, 2000 |
NZ |
509039 |
Nov 27, 2000 |
NZ |
508433 |
Jun 14, 2000 |
NZ |
505156 |
Nov 16, 2000 |
NZ |
508219 |
Claims
The claims defining the invention are as follows:
1. In a device for delivering a supply of gases to a user
comprising: a patient interface, in use in fluid communication with
said supply of gases and supplying said gases to said user, and at
least one outlet vent integrated with or in adjacent fluid
communication the improvement comprising a removable diffusing
member adapted to in use covering said vent, and diffuse a
substantial portion of the expired gases of said user.
2. In a device for delivering a supply of gases to a user as
claimed in claim 1 the improvement further comprising said
removable member in use diffusing and audibly muffling a
substantial portion of the expired gases of said user.
3. In a device for delivering a supply of gases to a user as
claimed in claim 2 the improvement further comprising said outlet
means including at least one low resistance outlet and at least one
high resistance outlet through which the expired gases of said user
flow out through.
4. In a device for delivering a supply of gases to a user as
claimed in claim 3 the improvement further comprising during normal
use the majority of said expired gases passing from said vent and
out through said low resistance outlet, whereby if the majority of
said expired gases are substantially prevented from passing through
said low resistance outlet, the majority of said expiratory gases
passing out said high resistance outlet.
5. In a device for delivering a supply of gases to a user as
claimed in claim 3 or 4 the improvement further comprising said
high resistance outlet is comprised of apertures in said patient
interface or said removable member or in the intersection
therebetween.
6. In a device for delivering a supply of gases to a user as
claimed in claim 3 or 4 the improvement further comprising said
high resistance outlet is adapted such that in use is said low
resistance outlet is blocked or has significant increase in
resistance, said high resistance outlet vents a sufficient flow gas
so as to prevent rebreathing of carbon dioxide by said user.
7. In a device for delivering a supply of gases to a user as
claimed in claim 3 or 4 the improvement further comprising said
removable member comprises a frame member and a disposable medium
in use juxtaposed between said frame member and said vent, said low
resistance outlet comprising the flow of said expired gases through
said disposable medium.
8. In a device for delivering a supply of gases to a user as
claimed in claim 7 the improvement further comprising said
disposable medium reducing the external audible noise level and
diffusing the flow pattern that would otherwise occur from said
gases flowing through said vent.
9. In a device for delivering a supply of gases to a user as
claimed in claim 7 the improvement further comprising said
disposable medium is a filter material.
10. In a device for delivering a supply of gases to a user as
claimed in any of claims 1 to 4 wherein said patient interface
comprises a nasal mask having a hard body portion, an inlet to said
body portion receiving said supply of gases, sealing means engaged
with said body portion, and adapted to seal against the facial
contours of said user, and means of securement to said user
providing a compressive force on said sealing means to ensure said
supply of gases is delivered to a user without significant leakage,
said vent comprising at least one aperture in said body
portion.
11. In a CPAP system for delivering gases to a user including a
pressurised source of gases, transport means in fluid communication
with said pressurised source adapted to convey said gases, and a
patient interface in fluid communication with said transport means
in use delivering said gases to said user, said patient interface
including: outlet means having at least one outlet vent, and a
removable diffusing member covering said vent, said outlet means in
use passing a substantial portion of the expired gases of said
user.
12. In a CPAP system as claimed in claim 11 the improvement further
comprising said patient interface is a nasal mask.
13. A removable diffusing member for covering at least one vent or
adjacent a gases delivery patient interface, comprising: a body
adapted to in use pass a substantial portion of expired gases from
a user; and means for removably connecting said body on or over
said at least one vent.
14. A removable diffusing member as claimed in claim 13 wherein
said removable diffusing member is adapted to in use diffuse and
audibly muffle a substantial portion of the expired gases of a user
flowing out from said at least one vent.
15. A removable diffusing member as claimed in claim 13 or 14,
wherein said body includes a frame member and a disposable medium,
said disposable medium adapted to be juxtaposed in use between said
frame member and said at least one vent, and in use a low
resistance outlet being formed by the flow of expired gases through
said disposable medium, said removable diffusing member further
comprising a high resistance outlet for the flow of expired gases
if said low resistance outlet in use becomes blocked.
16. A removable diffusing member as claimed in claim 15 wherein
said disposable medium is a filter material.
Description
[0001] This application is a continuation application of Ser. No.
09/881,394, filed on Jun. 14, 2001 (now allowed), and entitled
"Nasal Mask".
FIELD OF INVENTION
[0002] This invention relates to patient interfaces particularly
though not solely to nasal mask for use in providing CPAP therapy
to patients suffering from obstructive sleep apnea (OSA).
BACKGROUND OF THE INVENTION
[0003] In the art of respiration devices, there are well known a
variety of respiratory masks which cover the nose and/or mouth of a
human user in order to provide a continuous seal around the nasal
and/or oral areas of the face such that gas may be provided at
positive pressure within the mask for consumption by the user. The
uses for such masks range from high altitude breathing (i.e.,
aviation applications) to mining and fire fighting applications, to
various medical diagnostic and therapeutic applications.
[0004] One requisite of such respiratory devices has been that they
provide an effective seal against the user's face to prevent
leakage of the gas being supplied. Commonly, in prior mask
configurations, a good mask-to-face seal has been attained in many
instances only with considerable discomfort for the user. This
problem is most crucial in those applications, especially medical
applications, which require the user to wear such a mask
continuously for hours or perhaps even days. In such situations,
the user will not tolerate the mask for long durations and optimum
therapeutic or diagnostic objectives thus will not be achieved, or
will be achieved with great difficulty and considerable user
discomfort.
[0005] Where such masks as those used above are used in respiratory
therapy, in particular treatment of obstructive sleep apnea (OSA)
using Continuous Positive Airway Pressure (CPAP) therapy, there is
generally provided in the art a vent for washout of the bias flow
or expired gases to the atmosphere. Such a vent may be provided for
example, as part of the mask, or in the case of some respirators
where a further conduit carries the expiratory gases, at the
respirator. The washout of gas from the mask is essential to ensure
that carbon dioxide build up does not occur over the range of flow
rates. In the typical flow rates in CPAP treatment, usually between
4cm H.sub.2 O to 20 cm H.sub.2 O, prior art attempts at such vents
have resulted in excessive noise causing irritation to the user and
concentrated flows of gases irritating any bed partners.
[0006] Various approaches have been developed in the prior art to
attempt to reduce the noise when CPAP therapy is provided. For
example, in PCT Patent Application No. W098/34665 it has been
proposed that the vent include a resilient plug with rounded edges
at the apertures to reduce noise. In PCT patent application no
WO00178382 a vent is provided with a semi annular flap. However,
these prior art methods are not entirely satisfactory in
eliminating the extra noise created by a vent at the mask.
SUMMARY OF INVENTION
[0007] It is an object of the present invention to attempt to
provide a nasal mask which goes some way to overcoming the
abovementioned disadvantages in the prior art or which will at
least provide the industry with a useful choice.
[0008] Accordingly in a first aspect the invention consists in a
device for delivering a supply of gases to a user comprising:
[0009] a patient interface, in use in fluid communication with said
supply of gases and supplying said gases to said user, including at
least one outlet vent integrated or adjacent therewith and
[0010] a removable diffusing member adapted to in use covering said
vent, and diffuse a substantial portion of the expired gases of
said user.
[0011] Preferably a device for delivering a supply of gases to a
user as claimed in claim 1 wherein said removable member in use
diffusing and audibly muffling a substantial portion of the expired
gases of said user.
[0012] Preferably a device for delivering a supply of gases to a
user as claimed in claim 2 wherein said outlet means including at
least one low resistance outlet and at least one high resistance
outlet through which the expired gases of said user flow out
through.
[0013] Preferably a device for delivering a supply of gases to a
user as claimed in claim 3 wherein during normal use the majority
of said expired gases passing from said vent and out through said
low resistance outlet, whereby if the majority of said expired
gases are substantially prevented from passing through said low
resistance outlet, the majority of said expiratory gases passing
out said high resistance outlet.
[0014] Preferably a device for delivering a supply of gases to a
user as claimed in claim 3 or 4 wherein said high resistance outlet
is comprised of apertures in said patient interface or said
removable member or in the intersection there between.
[0015] Preferably a device for delivering a supply of gases to a
user as claimed in claim 3 or 4 wherein said high resistance outlet
is adapted such that in use is said low resistance outlet is
blocked or has significant increase in resistance, said high
resistance outlet vents a sufficient flow gas so as to prevent
rebreathing of carbon dioxide by said user.
[0016] Preferably a device for delivering a supply of gases to a
user as claimed in claim 3 or 4 wherein said removable member
comprises a frame member and a disposable medium in use juxtaposed
between said frame member and said vent, said low resistance outlet
comprising the flow of said expired gases through said disposable
medium.
[0017] Preferably a device for delivering a supply of gases to a
user as claimed in claim 7 wherein said disposable medium reducing
the external audible noise level and diffusing the flow pattern
that would otherwise occur from said gases flowing through said
vent.
[0018] Preferably a device for delivering a supply of gases to a
user as claimed in claim 7 wherein said disposable medium is a
filter material.
[0019] Preferably a device for delivering a supply of gases to a
user as claimed in any of claims 1 to 4 wherein said patient
interface comprises a nasal mask having a hard body portion, an
inlet to said body portion receiving said supply of gases, sealing
means engaged with said body portion, and adapted to seal against
the facial contours of said user, and means of securement to said
user providing a compressive force on said sealing means to ensure
said supply of gases is delivered to a user without significant
leakage, said vent comprising t least one aperture in said body
portion.
[0020] Preferably CPAP system for delivering gases to a user
including a pressurised source of gases, transport means in fluid
communication with said pressurised source adapted to convey said
gases, and a patient interface in fluid communication with said
transport means in use delivering said gases to said user, said
patient interface including:
[0021] outlet means having at least one outlet vent, and a
removable diffusing member covering said vent, said outlet means in
use passing a substantial portion of the expired gases of said
user.
[0022] Preferably a CPAP system as claimed in claim 11 wherein said
patient interface is a nasal mask.
[0023] In a second aspect the present invention consists in a CPAP
system for delivering gases to a user including a pressurised
source of gases, transport means in fluid communication with said
pressurised source adapted to convey said gases, and a patient
interface in fluid communication with said transport means in use
delivering said gases to said user, said patient interface
including:
[0024] outlet means having at least one outlet vent, and a
removable diffusing member covering said vent, said outlet means in
use passing a substantial portion of the expired gases of said
user.
[0025] In a third aspect the present invention consists in a
removable diffusing member for a gases delivery patient interface,
said removable member adapted to be juxtaposed on or over a vent,
associated with a patient interface and pass a substantial portion
of expired gases from a user flowing out from a vent.
[0026] Preferably a removable diffusing member as claimed in claim
13 wherein said removable member is adapted to in use diffuse and
audibly muffle a substantial portion of the expired gases of a user
flowing out from a vent.
[0027] Preferably a removable diffusing member as claimed in claim
13 or 14 comprising a frame member and a disposable medium, said
disposable medium adapted to be juxtaposed in use between said
frame member and a vent, and in use a low resistance outlet being
formed by the flow of expired gases through said disposable medium,
said removable diffusing member further comprising a high
resistance outlet for the flow of expired gases if said low
resistance outlet in use becomes blocked.
[0028] Preferably a removable diffusing member as claimed in claim
15 wherein said disposable medium is a filter material.
[0029] To those skilled in the art to which the invention relates,
many changes in construction and widely differing embodiments and
applications of the invention will suggest themselves without
departing from the scope of the invention as defined in the
appended claims. The disclosures and the descriptions herein are
purely illustrative and are not intended to be in any sense
limiting.
[0030] The invention consists in the foregoing and also envisages
constructions of which the following gives examples.
BRIEF DESCRIPTION OF THE DRAWINGS
[0031] One preferred form of the present invention will now be
described with reference to the accompanying drawings in which;
[0032] FIG. 1 is a block diagram-of a humidified continuous
positive airway pressure (CPAP system) as might be used in
conjunction with the present invention,
[0033] FIG. 2 is an illustration of the nasal mask in use according
to the preferred embodiment of the present invention,
[0034] FIG. 3 is a front view of the nasal mask illustrating the
headgear securement to the mask,
[0035] FIG. 4 is a perspective view of the mask illustrating the
plurality of engaging clips to connect to the sliding strap
[0036] FIG. 5 is a perspective view of the mask showing the sliding
strap clipped into the engaging clips,
[0037] FIG. 6 is a side view showing the sliding strap,
[0038] FIG. 7 is a perspective view of the mask illustrating the
outlet vents,
[0039] FIG. 8 is a perspective view of the mask illustrating the
vent cap in place, and
[0040] FIG. 9 is a perspective view of the vent cap.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0041] The present invention provides improvements in the field of
CPAP therapy. In particular an outlet is described which is quieter
and has a more diffused outlet flow. It will be appreciated that
the nasal mask as described in the preferred embodiment of the
present invention can be used in respiratory care generally or with
a ventilator but will now be described below with reference to use
in a humidified CPAP system. It will also be appreciated that the
outlet vent described is equally applicable to all forms of patent
interface, in particular a mouth piece.
[0042] With reference to FIG. 1 a humidified Continuous Positive
Airway Pressure (CPAP) system is shown in which a patient 1 is
receiving humidified and pressurised gases through a nasal mask 2
(or other types of patient interface as appropriate) connected to a
humidified gases transportation pathway or inspiratory conduit 3.
It should be understood that delivery systems could also be VPAP
(Variable Positive Airway Pressure) and BiPAP (Bi-level Positive
Airway Pressure) or numerous other forms of respiratory therapy.
Inspiratory conduit 3 is connected to the outlet 4 of a
humidification chamber 5 which contains a volume of water 6.
Inspiratory conduit 3 may contain heating means or heater wires
(not shown) which heat the walls of the conduit to reduce
condensation of humidified gases within the conduit. Humidification
chamber 6 is preferably formed from a plastics material and may
have a highly heat conductive base (for example an aluminium base)
which is in direct contact with a heater plate 7 of humidifier 8.
Humidifier 8 is provided with control means or electronic
controller 9 which may comprise a microprocessor based controller
executing computer software commands stored in associated
memory.
[0043] Controller 9 receives input from sources such as user input
means or dial 10 through which a user of the device may, for
example, set a predetermined required value (preset value) of
humidity or temperature of the gases supplied to patient 1. The
controller may also receive input from other sources, for example
temperature and/or flow velocity sensors 11 and 12 through
connector 13 and heater plate temperature sensor 14. In response to
the user set humidity or temperature value input via dial 10 and
the other inputs, controller 9 determines when (or to what level)
to energise heater plate 7 to heat the water 6 within
humidification chamber 5. As the volume of water 6 within
humidification chamber 5 is heated, water vapour begins to fill the
volume of the chamber above the water's surface and is passed out
of the humidification chamber 5 outlet 4 with the flow of gases
(for example air) provided from a gases supply means or blower 15
which enters the chamber through inlet 16. Exhaled gases from the
patient's mouth are passed directly to ambient surroundings in FIG.
1.
[0044] Blower 15 is provided with variable pressure regulating
means or variable speed fan 21 which draws air or other gases
through blower inlet 17. The speed of variable speed fan 21 is
controlled by electronic controller 18 (or alternatively the
function of controller 18 could carried out by controller 9) in
response to inputs from controller 9 and a user set predetermined
required value (preset value) of pressure or fan speed via dial
19.
[0045] Nasal Mask
[0046] Referring to FIG. 2 the nasal mask, according to the
preferred embodiment of the present invention, is shown in detail.
The mask includes a hollow body 102 with an inlet 103 connected to
the inspiratory conduit 3. The mask 2 is positioned around the nose
of the user I with the headgear 108 secured around the back of the
head of the patient 1. The restraining force from the headgear 108
on the hollow body 102 and the forehead rest 106 ensures enough
compressive force on the mask cushion 104, to provide an effective
seal against the patient's face.
[0047] The hollow body 102 is constructed of a relatively
inflexible material for example, polycarbonate plastic. Such a
material would provide the requisite rigidity as well as being
transparent and a relatively good insulator. The expiratory gases
in the preferred embodiment of the present invention are expelled
through a valve in the mask 300, or alternatively a further
expiratory conduit (not shown), or any other such method as is
known in the art.
[0048] Mask Headgear
[0049] Referring now to FIGS. 2 and 3 the headgear 108 is shown
connected to the hollow body 102. Rather than traditional fixed or
adjustable attachments the present invention utilises a sliding
engagement between the headgear 108 and the hollow body 102. This
is achieved with a loop 120, running through harnessing clips 122,
124 on either side of the headgear 108 and over the top of the
hollow body 102. The loop 120 is reciprocally engaged with guides
126, 128 mounted on the top surface of the hollow body 102. The
guides constrain the loop 120 but allow it to slide in and out,
meaning the headgear 108 can move laterally, independently of the
hollow body 102.
[0050] The advantage to this is as the face is contorted during
various sleeping positions the headgear is able to move with the
changes in position while the mask is left in the correct position
on the nose of the user and an effective seal is maintained.
[0051] Additional guides 129, 130, 131 allow the user to adjust
position of loop 120, giving ability to get different pressure-on
the seal depending on loop 120 position.
[0052] To further ensure user comfort and effective pressure on the
mask cushion 104, the headgear 108 may be constructed either using
two straps running around the back of the user's head as shown in
FIG. 2 or with a partial skull cap or any other configurations as
are known in the art. In this case the straps or partial skull cap
would be constructed using neoprene but may also be constructed
using any material as is known in the art which will be comfortable
for the user.
[0053] In a further embodiment shown in FIGS. 4, 5 and 6 the
present invention is illustrated using a sliding strap to attach
the headgear 108 to the hollow body 102. The strap 200, shown in
FIG. 6 in isolation, is constructed of polyacetal (Delrin 500P
NC010) using injection moulding techniques to give a polished
finish. This material, similar to other nylon based derivatives,
with its polished finish has a particularly low friction
co-efficient, slides with respect to the hollow body 102 with very
little resistance. As shown in FIG. 4, the hollow body 102 includes
a number of engaging clips 202, in use the sliding strap 200 snaps
into place into the engaging clips 202 and can only be removed
therefrom using a substantial force. This means that with any
normal use the sliding strap 200 will stay retained within the
engaging clips 202. It will also be appreciated from FIG. 4 that a
number of clips are so provided, in order to allow pressure from
different angles for different face shapes.
[0054] As shown in FIG. 6 the sliding strap includes a mid-section
204 intended to reciprocate with the engaging clips 202, terminated
at each end by loops 206, 208 which attach to the headgear. The
first loop 206 is a full loop through which the headgear 108 is
permanently attached with for example, a velcro strap. The loop 208
at the other end, is only a partial loop 210 designed so that a
strap or loop from the headgear 108 can be easily slipped in or out
of the open section 212 to allow easy removal and attachment of the
mask.
[0055] Outlet Vent
[0056] In a further improvement shown in FIGS. 7 to 9 the present
invention includes an outlet vent 300 as part of the body portion.
The outlet vent 300 includes a number of apertures 302 either
moulded in the body portion 102 or drilled through after moulding.
The apertures 302 are separated and to some extent surrounded by a
number of partitions 304 which provide support for a filter cap
which is installed over top of the apertures 302. The filter cap is
designed primarily prevent what would otherwise be the noise
generated from the flow of gases through the apertures 302
externally. This filter cap comprises a frame member 306 (shown in
FIG. 9) which snaps on over top of the partition 304 and holds in
place a piece of filter medium 308 which sits over top of the
partitions 304. The frame 306 includes large vents 307 such that
the expiratory or bias flow from the mask flows out the apertures
302 through the filter medium 308 and out the vent 307. The piece
of filter medium 308 is preferably Ecofilt brand filter medium
(PM135) which is less prone to blocking from the humidity levels
often found in such applications.
[0057] The structure of the outlet vent allows for the filter
medium to be replaced as and when necessary in an easy and
efficient manner. The frame 306 can be easily removed, the filter
medium 308 replaced and the frame 306 snapped on back in place.
Further in the rare event of the filter medium blocking, auxiliary
vents 310 are provided in the frame 306 which match up with gaps
312 in the partitions 304. As the auxiliary vents 310 are much
smaller than the main vents 307 during normal use very little flow
passes through them. If the filter medium 108 becomes blocked the
flow is then forced through the auxiliary vents 310. This will be
significantly more noisy than normal and will indicate the need for
maintenance to the user.
[0058] It will be appreciated that by providing such a system the
present invention effectively minimises the noise generated by the
outward flow of expiratory gases from the mask. The present
invention is of a low maintenance type and when replacement of the
filter medium is required, it is an easy and simply exercise. As
well as reducing the noise level the flow through the outlet vent
is more diffused. This avoids for example, a flow of gases directed
at a sleeping partner or a similar flow directed at the patient,
either of which causing restlessness or waking.
* * * * *