U.S. patent application number 12/271927 was filed with the patent office on 2009-03-12 for parameter optimization in sleep apnea treatment apparatus.
Invention is credited to Ruth O. Childers, Winthrop D. Childers.
Application Number | 20090065004 12/271927 |
Document ID | / |
Family ID | 40138423 |
Filed Date | 2009-03-12 |
United States Patent
Application |
20090065004 |
Kind Code |
A1 |
Childers; Winthrop D. ; et
al. |
March 12, 2009 |
Parameter Optimization in Sleep Apnea Treatment Apparatus
Abstract
The present invention includes a method and apparatus for the
optimized treatment of obstructive sleep apnea. The present
invention includes a pressure source configured to provide positive
airway pressure to a patient who is resting at home. The pressure
source receives control signals from control electronics that
define a pressure profile to be delivered to the patient. The
control electronics select parameters to define the pressure
profile based on factors such as a user selection, information
received from a sensor, and/or a prescription.
Inventors: |
Childers; Winthrop D.; (San
Diego, CA) ; Childers; Ruth O.; (San Diego,
CA) |
Correspondence
Address: |
WINTHROP D. CHILDERS
9855 FOX VALLEY WAY
SAN DIEGO
CA
92127
US
|
Family ID: |
40138423 |
Appl. No.: |
12/271927 |
Filed: |
November 16, 2008 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
11224548 |
Sep 12, 2005 |
7469698 |
|
|
12271927 |
|
|
|
|
60609897 |
Sep 14, 2004 |
|
|
|
Current U.S.
Class: |
128/204.23 |
Current CPC
Class: |
A61M 2205/276 20130101;
A61M 2205/502 20130101; A61M 16/00 20130101; A61M 16/0051 20130101;
A61M 2205/52 20130101; A61M 16/107 20140204; A61M 16/024
20170801 |
Class at
Publication: |
128/204.23 |
International
Class: |
A61M 16/00 20060101
A61M016/00 |
Claims
1. An apparatus for treating sleep apnea of a patient comprising:
an apparatus including a pressure source configured to be coupled
to the airway of a patient during a treatment cycle; an information
storage device configured to store information defining a plurality
of different operating modes including a selected operating mode
defining a selected pressure profile; a user interface configured
to receive an input from a patient that activates the selected
operating mode; and a controller configured to operate the pressure
source using the selected pressure profile.
2. The apparatus of claim 1 wherein the controller is configured to
receive prescription operating parameter information and wherein
the prescription operating parameter information defines the
selected pressure profile.
3. The apparatus of claim 1 wherein the selected operating mode
defines an initial pressure profile and an incident pressure
profile and wherein the controller is configured to operate the
pressure source using the initial pressure profile before an
obstructive event and to operate the pressure source using the
incident pressure profile in response to an obstructive event.
4. The apparatus of claim 3 wherein the user interface is
configured to receive a selection from the patient modifying the
initial pressure profile to provide a new initial pressure profile
and wherein the controller is configured to operate the pressure
source according to the new initial pressure profile during the
treatment cycle before an obstructive event occurs.
5. The apparatus of claim 1 further comprising a sensor apparatus
configured to generate a signal during the treatment cycle and
wherein the controller is configured to identify obstructive events
based upon the signal and to store additional information based
upon identifying the obstructive events.
6. The apparatus of claim 5 wherein the controller is configured to
define a new custom operating mode based upon the additional
information.
7. An apparatus for treating sleep apnea of a patient comprising:
an apparatus including a pressure source configured to be coupled
to the airway of a patient during a treatment cycle; an information
storage device storing information defining an operating mode; a
user interface configured to receive an input from the patient that
defines a variable operating mode parameter; and a controller
configured to: (1) read the selection from the patient that defines
the variable operating mode parameter; and (2) operate the pressure
source using the operating mode and according to variable operating
mode parameter.
8. The apparatus of claim 7 wherein the variable operating mode
parameter defines an initial applied pressure versus time profile
that is applied during the treatment cycle before an obstructive
event occurs.
9. The apparatus of claim 7 wherein the controller is configured to
receive prescription operating parameter information and to store
the prescription operating parameter information on the information
storage device and wherein the prescription operating parameter
information defines the operating mode.
10. The apparatus of claim 7 further comprising a sensor apparatus
configured to generate a signal during the treatment cycle and
wherein the controller is further configured to: (1) analyze the
signal to determine if the operating mode is sufficient to treat
obstructive events; and (2) store information on the information
storage device defining a new operating mode to replace the
operating mode if the operating mode is not sufficient to treat
obstructive events.
11. The apparatus of claim 7 further comprising a sensor apparatus
configured to generate a signal during the treatment cycle and
wherein the controller is further configured to: (1) analyze the
signal; (2) determine if there is sufficient operating margin
provided by the operating mode based upon analyzing the signal; and
(3) generate a warning if there is not sufficient operating margin
provided by the pressure profile.
12. The apparatus of claim 7 further comprising a sensor apparatus
configured to generate a signal in response to obstructive events
during the treatment cycle and wherein the controller is further
configured to store a record indicative of obstructive events
during the treatment cycle.
13. An apparatus for treating sleep apnea of a patient comprising:
an apparatus including a pressure source configured to be coupled
to the airway of a patient during a treatment cycle; a sensor
apparatus configured to generate a signal during the treatment
cycle; an information storage device storing first information
defining an operating mode that defines an initial pressure profile
and an incident pressure profile; and a controller configured to:
(1) read the first information defining the operating mode; (2)
operate the pressure source to provide the initial pressure
profile; (3) analyze the signal from the sensor apparatus during
the treatment cycle; (4) identify an obstructive event based upon
analyzing the signal; (5) operate the pressure source to provide
the incident pressure profile in response to identifying the
obstructive event; and (6) store second information on the
information storage device as a result of analyzing the signal
wherein the second information is indicative of whether a new
operating mode is required.
14. The apparatus of claim 13 wherein the second information
defines new operating mode parameters defining a new pressure
profile.
15. The apparatus of claim 14 wherein the controller is configured
to automatically operate the pressure source according to the new
operating mode parameters.
16. The apparatus of claim 14 wherein the controller is configured
to automatically modify the incident pressure profile based upon
the new operating mode parameters.
17. The apparatus of claim 13 wherein the controller is configured
generate a warning if the new operating mode is required.
18. The apparatus of claim 13 wherein the controller is configured
to receive prescription information that defines the first
information.
19. The apparatus of claim 13 further comprising a user interface
configured to receive a selection from the patient that defines a
modification to the initial pressure profile defining a new initial
pressure profile and wherein the controller is configured to apply
the new initial pressure according to step (2) of claim 13.
20. The apparatus of claim 13 wherein the second information
includes a record of obstructive events that occur during the
treatment cycle.
Description
RELATED APPLICATIONS
[0001] This non-provisional application is a continuation of U.S.
Non-Provisional Application Ser. No. 11/224,548 entitled "Parameter
Optimization in a Sleep Apnea Treatment Apparatus", filed Sep. 12,
2005. U.S. Non-Provisional Application Ser. No. 11/224,548 claims
priority to U.S. Provisional Application Ser. No. 60/609,897,
Entitled "Parameter Optimization in a Sleep Apnea Treatment
Apparatus" by Winthrop D. Childers and Ruth O. Childers, filed on
Sep. 14, 2004, incorporated herein by reference under the benefit
of U.S.C. 119(e).
FIELD OF THE INVENTION
[0002] The present invention relates to the treatment of sleep
disorders. More particularly, the present invention relates to a
method and apparatus for optimizing the treatment of obstructive
sleep apnea.
BACKGROUND
[0003] OSA (obstructive sleep apnea) is a disease that adversely
affects an estimated more than 10 million adults in the United
States alone. The disorder manifests itself when a person has
repeated trouble breathing at night. The trouble breathing results
from a collapse and hence obstruction of the pharynx (throat air
passage). When this occurs, at the least it disturbs sleep but can
also cause cardiac arrest. Those who suffer from OSA tend to have
excessive daytime sleepiness, which can lead to lost productivity
and accidents.
[0004] The best method for treating OSA is with a device that
provides PAP (positive airway pressure) to a patient at night. The
patient typically wears a mask such as a mask that fits over the
nose. The mask is pressurized with a gas such as air that is
maintained a positive gauge pressure that may be in the range of 5
to 25 cm of water. The positive pressure applied to the nose will
tend to prevent obstruction by distending the collapsible throat
air passage.
[0005] The most general form of PAP is CPAP, or continuous positive
airway pressure. This is effective, but it can have some drawbacks.
For some patients with weakened pulmonary systems, breathing in and
out with constant pressure may be labored. For those patients in
particular PAP systems that provide variation in pressure that is
timed with the cycle of breathing is preferred. This application of
pressure is referred to as IPAP (inspiratory positive airway
pressure) and EPAP (expiratory positive airway pressure).
[0006] Historically OSA has been treated in sleep clinics where the
OSA problem can be diagnosed and treated. This tends to be quite
expensive, impractical, and uncomfortable. To address these issues,
PAP devices have been designed for the home. The devices are
relatively inexpensive; in fact, one such device may cost less than
spending a few days in a sleep clinic. But along with a great
benefit, sending such devices home with patients creates some new
issues.
[0007] Such issues with take-home PAP systems have to do with
patient-to-patient variations and with variations in a particular
patient's condition. Historically the proper settings for a PAP
device need to be determined in a sleep clinic. This is very
expensive and probably impractical given the number of those
victimized by OSA. In addition, when a patient has time-based
variations this cannot be properly addressed by a sleep clinic.
There is a need for a take home PAP apparatus that can address
these patient to patient and time based variations.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 is a schematic representation of a PAP (positive
airway pressure) treatment apparatus of the present invention.
[0009] FIG. 2 is a schematic block diagram of a PAP (positive
airway pressure) treatment apparatus of the present invention.
[0010] FIG. 3 is a schematic block diagram of a PAP (positive
airway pressure) treatment apparatus of the present invention.
[0011] FIG. 4a is an illustration of a portion of a user interface
utilized in the PAP (positive airway pressure) treatment apparatus
of the present invention for selecting an operating mode.
[0012] FIG. 4b is an illustration of a portion of a user interface
utilized in the PAP (positive airway pressure) treatment apparatus
of the present invention during operation.
[0013] FIG. 5 is a flow chart representation of a method whereby
the PAP of the present invention selects between standard and
custom operating modes.
[0014] FIG. 6 is a flow chart representation of a method whereby
the PAP of the present invention is operated in a way that is
optimal either for a long-term condition or a transient condition
of a patient.
[0015] FIG. 7 is a flow chart representation of a method whereby
the PAP of the present invention is receives updated operating
parameters from a prescription.
[0016] FIG. 8 is a flow chart representation of a method whereby
the PAP of the present invention generates new custom operating
parameters based on analyzing information based on an acoustic
signal monitored in the mask.
[0017] FIG. 9 is a flow chart representation of a method whereby
the PAP of the present invention generates new custom operating
parameters based on analyzing information based on an acoustic
signal monitored in the mask.
[0018] FIG. 9a depicts an initial pressure versus time profile
which corresponds to element 118 of FIG. 9.
[0019] FIG. 9b depicts an incident pressure versus time profile
which corresponds to element 122 of FIG. 9.
[0020] FIG. 9c depicts a third pressure profile which corresponds
to element 126 of FIG. 9.
[0021] FIG. 10 is a flow chart representation of a method whereby
the PAP of the present invention utilizes information from an
external sensor to derive a more accurate representation of
acoustic noises generated internal to a patient's respiratory
system.
[0022] FIG. 11 is a flow chart representation of a method whereby
the PAP of the present invention generates and compares a digital
signature representation of an acoustic noise pattern over time
versus an internally stored digital signature.
[0023] FIG. 12 is a flow chart representation of a method whereby
the PAP of the present invention utilizes analysis of sounds inside
the mask to determine whether a transient condition is present and
to utilize parameters consistent with the determination.
[0024] FIG. 13 is a flow chart representation of a method whereby
the PAP of the present invention determines whether an insufficient
operating margin requires a new prescription.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0025] The present invention is a PAP (positive airway pressure)
apparatus configured for use in the home and suitable for treatment
of OSA (obstructive sleep apnea). A PAP device of the present
invention can be a CPAP (continuous positive airway pressure)
device or an IPAP/EPAP (inspiratory positive airway
pressure/expiratory positive airway pressure) device. The PAP of
the present invention operates or provides "treatment cycles" in
multiple modes including a "standard" mode governed by a "standard"
set of operating parameters and a "custom" mode governed by a
"custom" set of operating parameters. A "treatment cycle" is
essentially the complete cycle of "pressure profiles" provided to a
patient during a sleep cycle. An example of a "treatment cycle" is
discussed with respect to FIG. 9. A "pressure profile" is a
pressure versus time applied by the PAP device. Examples of
pressure profiles are described with respect to FIGS. 9, 9a, 9b,
and 9c.
[0026] The PAP apparatus of the present invention includes a mask
that is coupled to a controllable pressure source under control of
control electronics. The control electronics are coupled to an
information storage device and to an input selection device. The
information storage device stores information indicative of the
operating parameters. From here forward, when we say that the
information storage devices "stores" parameters, we mean that the
device stores information indicative of the parameters that can be
utilized by the control electronics to cause operation of the
pressure source that is consistent with the parameters.
[0027] The operating parameters include "variable" parameters that
can be customized according to the needs of a patient. The
information storage device provides storage for redundant values
for each of the variable parameters. Thus, for each variable
parameter, a "standard version" is stored and one or more "custom
versions" are stored. The controller is configured to operate in a
"standard" mode when it utilizes a set of standard parameters and
to operate in a custom mode when it utilizes a set of custom
parameters.
[0028] The controller selects an operating mode in response to a
mode signal from the input selection device. When the mode signal
is received, the controller then loads and/or utilizes a set of
parameters for the particular mode selected. The mode may be
customized according to the particular patient's intermediate or
long term therapeutic needs. Alternatively, the mode may be
selected in response to a shorter term transient condition of the
patient.
[0029] A PAP treatment apparatus 2 configured for home based
treatment of sleep apnea is depicted schematically in FIG. 1 and in
schematic block diagram form in FIG. 2. The treatment apparatus 2
includes a pressure source 4 that is fluidically coupled to a mask
6 via a conduit 8. In one embodiment, the pressure source 4
includes a blower 10 and a pressure modulator 12. During use a
patient wears mask 6. PAP treatment apparatus applies positive
pressure to the mask via the pressure source 4. In the embodiment
wherein the pressure source 4 includes blower 10 and pressure
modulator 12, the pressure modulator 12 enhances the speed of
response and accuracy of the pressure source 4.
[0030] The PAP treatment apparatus 2 includes a controller 14 that
is coupled to a sensor 16, an information storage device 18, an
input selection device 20, user interface 21, and the pressure
source 4. In some embodiments, input selection device is a portion
of user interface 21. The controller 14 receives inputs from sensor
16, information storage device 18, input selection device 20, and
in provides control signals to pressure source 4.
[0031] The information storage device stores information indicative
of operating parameters for operating the pressure source 4. The
operating parameters include fixed operating parameters that do not
vary according to a particular operating mode and variable
operating parameters that do vary according to a particular
operating mode.
[0032] The information storage device stores first or standard
operating parameter information 22 and second or custom operating
parameter information 24 for each of the variable operating
parameters. The standard operating parameter information 22 defines
a first or standard operating mode for PAP treatment apparatus 2.
The custom operating parameter information 24 defines a second or
custom operating mode for PAP treatment apparatus 2.
[0033] The controller receives a mode selection from inputs
selection device 20 and operates PAP treatment apparatus in a
manner consistent with the mode selected. If a first or standard
mode is selected, then controller 14 utilizes standard parameters
22. If a second or custom mode is selected, then controller 14
utilizes custom parameters 24.
[0034] An exemplary PAP treatment apparatus 2 is depicted in more
detailed block diagram form in FIG. 3. In the exemplary embodiment,
air is received by inlet filter 26 which passes filtered air to an
intake of pressure generator 10. Pressure generator 10 supplies
pressurized air to an air manifold 30 that "warehouses" pressurized
air. Manifold 30 passes air to conduit 32 via valve 34. Together
manifold 30 and valve 34 operate together as modulator 12. Finally,
conduit 32 provides pressurized air to mask 6 worn by the patient.
In this embodiment, the manifold 30 is maintained at a higher gauge
pressure than conduit 32 under control of controller 14.
[0035] Controller or control electronics 14 is coupled to
information storage device 18, input selection device 20, pressure
generator 10, valve 34, acoustic sensor or microphone 16, conduit
sensor 38, pressure sensor 40, external sensor 42, and aerosol
generation device 44. Similar to the embodiment discussed with
respect to FIGS. 1 and 2, information storage device 18 stores
variable operating parameters that includes a first or standard set
of operating parameters and a second or custom set of operating
parameters. The controller 14 is configured to receive an
instruction from the input selection device 20 and in response to
operate pressure generator 10 and pressure modulator 12 using the
selected operating parameters.
[0036] The input selection device 20 is configured to impart a
signal to controller 14 indicative of one or more operating modes
for controller 14. An appropriate input selection device can take
on any number of forms including a memory card, flash memory, a
user selected switch, and LCD touch screen interface, a wireless
link, a sensor signal, a "fire-wire" or USB link, an RFID device
input, or any other input device that is capable of imparting a
signal to controller 14 indicative of an operating mode.
[0037] Based upon a mode selected via input selection device 18,
controller 14 selects operating parameters that define operation of
the PAP treatment device 2 for a treatment cycle. Operating
parameters include applied pressure profiles, therapeutic pressure
levels, a maximum pressure level, aerosol parameters, and other
factors that may be important for a given patient condition. A
pressure profile defines a pressure versus time curve to be applied
to mask 6. A therapeutic pressure level defines a pressure applied
to mask 6 intended to open or prevent obstruction of the throat air
passage. A maximum pressure level defines an upper limit for air
pressure to be applied to mask 6. Finally aerosol parameters define
operating instructions for aerosol generation device 44.
[0038] Controller 14 receives signals from one of mask sensors 16
such as a microphone 16 that can be indicative of an obstructive
event. Controller 14 also receives information from an external
sensor 42 that can be a microphone external to mask 6. Controller
14 can utilize information from the external sensor 42 to subtract
our or compensate for noises external to mask 6. Controller 14
utilizes information received input selection device 20,
information storage device 18, microphone 16, and external sensor
42 to select a pressure profile applied to mask 6 and to operate
aerosol generation device 44.
[0039] The pressure profile applied to mask 6 can be rapidly and
precisely modulated via a pressure control system that includes
pressure generator 10 and pressure modulator 12. Pressure modulator
12 includes manifold 30 and valve 34 under control of controller
14. Controller 14 receives a signal from pressure sensor 40 that is
indicative of a manifold pressure level in manifold 30. In the
example wherein pressure generator 10 is a fan, the controller 14
adjusts a fan speed to maintain the pressure in manifold 30 within
a desired pressure range. Controller 14 receives a signal from a
sensor 38 in conduit 8 and/or mask 6 that is indicative of the
pressure level in conduit 8. Controller opens and closes valve 34
to maintain a desired pressure range in mask 6. The use of a
manifold 30 and valve 34 to regulate pressure in mask 6 allows
controller 14 to very precisely and rapidly modulate pressure in
mask 6. This is particularly important for IPAP/EPAP systems or
where a rapid response to an obstructive event is required. In
order for the mask pressure to be properly controlled and for rapid
responses, the pressure in manifold 30 is maintained at a level
above the anticipated required pressure ranges for mask 6.
[0040] FIGS. 4a and 4b depict an exemplary user interface 21 for
PAP apparatus 2 including a backlit LCD (liquid crystal display) or
OLED (organic light emitting diode) touch screen 46. FIG. 4a
depicts a view displayed by screen 46 used to select an operating
mode for PAP apparatus 2 and FIG. 4b depicts a view displayed by
screen 46 during operation. According to FIG. 4a, the operating
modes include a standard operating mode that is selected via a top
button 48 that would activate the "defaults" for apparatus 2.
[0041] By selecting button 50, a "custom" mode can be selected that
utilizes operating parameters that have been customized and
optimized for the particular patient using PAP apparatus 2. This
mode may have one or more particular pressure profiles (defined
pressure versus time that is applied to mask 6) that is/are more
comfortable or effective for the particular patient.
[0042] By selecting button 52, parameters indicative of a
prescription may be utilized. For example a prescription may have
been provided that allows for a higher maximum therapeutic pressure
than the standard operating mode would allow.
[0043] By selecting button 54, parameters indicative of a transient
condition such as a cold congestion can be utilized. For example,
selecting button 54 may activate aerosol device 44 and it may
provide a pressure profile that is effective for the particular
transient condition.
[0044] By selecting button 56, the aerosol device 44 may emit a
medicated aerosol. In the illustrated example, buttons 50-56 may be
individually selected or all selected at once if there are various
customizations and/or transient conditions required for the
operation of sleep apnea therapy device 2.
[0045] After the "START" 58 button is selected, apparatus 2 begins
operating and then displays a screen according to FIG. 4b that
indicates selected settings and a condition of filter 26. According
to FIG. 4b, the filter has 9% of its expected life remaining and a
"WARNING" indicator is displayed to alert the user that the filter
is in need of replacement.
[0046] An exemplary operation of PAP treatment apparatus is
depicted in FIG. 5. According to 60, parameters are stored on
information storage device 18 including standard parameters 22
indicative of a "standard" operating mode and custom parameters 24
indicative of a "custom" operating mode. According to 62, the apnea
treatment apparatus 2 configured for home use is provided to the
patient. In one embodiment, 60 can occur before 62--apparatus 2 can
be provided to the patient with the parameters already loaded.
Alternatively, 62 can occur before 60.
[0047] According to 64, an input selection indicative of a standard
operating mode or a custom operating mode is imparted to controller
14 via input selection device 20. According to 66, a decision is
made by controller 14 depending upon whether the standard or custom
mode is selected. If the standard mode is selected then controller
selects standard parameters 22 according to 68 and operates
apparatus 2 according to the standard parameters 22 according to
70. If the custom mode is selected, then the controller selects
custom parameters 24 according to 72 and operates the apparatus
using the custom parameters 24 according to 74.
[0048] An exemplary embodiment of the operation of PAP apparatus 2
for treating a transient condition is depicted with respect to FIG.
6. According to 76 a sleep apnea treatment apparatus 2 configured
for home use is provided to a patient. According to 78, the patient
makes a selection using input selection device 20 to operate the
device according to a long-term condition or a transient condition.
Stated another way, the user either selects a first operating mode
whose variable operating parameters are more optimal for a
long-term condition or a second operating mode whose variable
operating parameters are more optimal for a transient condition
(such as congestion resulting from a viral infection).
[0049] A decision 80 is made based on the selection. According to
82, if the long-term or first mode is selected, then treatment
apparatus 2 is operated according to long-term optimized
parameters. According to 84, if the transient or second operating
mode is selected, then apparatus 2 is operated utilizing transient
operating mode parameters. These may include, for example,
increased breathing assistance pressures or the like for example to
offset nasal congestion. According to 86, these parameters may also
include inputting medicated aerosol into conduit 8 and hence to
mask 6. The medicated aerosol may be generated by aerosol
generation device 44.
[0050] Another exemplary embodiment of the operation of PAP
apparatus 2 updated by a prescription is depicted with respect to
FIG. 7. According to 88, a patient receives a prescription that
defines operating parameters for treatment apparatus 2. An example
of such an operating parameter might be the maximum operating
pressure. This typically will be in the 8-20 cm of water (positive
gauge pressure) range in the "default" or standard case. For some
patients, the required maximum therapeutic pressure may be greater
than 20 cm of water for example.
[0051] Other possible parameters by prescription 88 might include:
(1) the dispensing of aerosolized medicants for the purpose of
clearing a transient congestion problem, or (2) other operational
aspects like a time-pressure integral factor. According to 90, the
prescription operating parameter information that is usable by
apparatus 2 is generated or derived from the prescription.
[0052] Then according to 92, the information is transferred to the
information storage device 18. This can be done any number of ways.
For example, a physician may have a computer for storing
prescription or operating parameter information on a flash memory
card. Alternatively, the doctor may authorize a separate entity
(such a as a service provider) to provide a memory device, an
internet transmission, or some other means of providing the proper
operating parameters to the information storage device 18.
[0053] According to 94, the controller 14 receives an input from
selection device that is indicative of the prescription. This could
be a user selection from a menu as depicted in FIGS. 4a/b, or it
could be the act of plugging in a memory card storing the
parameters.
[0054] According to 96 and 98, the control electronics then load
the prescription operating parameter information and operate
treatment apparatus 2 pursuant to the prescription operating
parameter information.
[0055] An exemplary embodiment of the operation of apnea treatment
apparatus is depicted with respect to FIG. 8 wherein the treatment
apparatus generates a custom set of operating parameters as a
result of analyzing operational results during a treatment.
According to 100 an apnea treatment apparatus 2 configured for home
use is provided to a patient.
[0056] According to 102 and 104, the controller 14 reads operating
parameter information parameter information from the information
storage device 18 and operates the treatment apparatus applying a
pressure versus time to mask 6 pursuant to the operating parameter
information read according to 102. According to 106, the controller
14 monitors a signal received from microphone 16 that is indicative
of a sound intensity versus time in mask 6. According to 108 the
controller then derives resulting information indicative sound
intensity versus time.
[0057] According to 110, the controller 14 analyzes the resulting
information in order to generate or compute a new custom set of
operating parameters. According to 112, the new custom set of
operating parameters is then stored on the information storage
device.
[0058] A specific treatment cycle that is similar to that depicted
with respect to FIG. 8 is now depicted with respect to FIG. 9 in
flow chart form. According to 114, operating parameter information
is provided from information storage device 18 to controller 14.
According to 116 a signal is monitored that is indicative of sounds
reaching mask 6. The signal is derived from microphone 16.
According to 118, a first or initial pressure profile 118 is
applied to mask 6. The first pressure profile is defined by the
operating parameters provided according to 114 and is an initial
applied pressure versus time profile.
[0059] An exemplary first pressure profile 118 is the initial
pressure versus time profile depicted with respect to FIG. 9a. When
the patient is first falling asleep, a comfortable first pressure
P1 is applied to mask 6 according to portion 118a of profile 118
between times t1 and t2. First pressure P1 may, for example, be in
the range of 0 to 4 cm of water positive gauge pressure. After
allowing time to fall asleep, the pressure then ramps up according
to portion 118b of profile 118 between times t2 and t3. Finally,
the pressure level reaches a second pressure P2 that may be in the
range of 3 to 8 cm of water for example and this pressure P2 is
maintained at a constant level during portion 118c of profile 118.
Pressure levels P1 and P1, the slope between time t2 and t3, as
well as the time durations of portions 118a, 118b, and 118c are
each defined by the parameters provided according to 114 in this
example.
[0060] Variations are possible as FIG. 9a is for illustrative
purposes only. For example pressure versus time curve 118 may be
non-linear, or may have multiple flat and sloped portions. The
parameters loaded according to 114 define portions of curve 118
individually, or else a single parameter may define the entire
curve according to a lookup table. The lookup table in this case
would have pressure versus time information for controlling the
pressure in mask 6 and a single parameter may select different
curves. Also, the magnitude of pressures P1 and P2 may vary
markedly depending on the needs of the patient.
[0061] According to 120, a decision is made by controller--has a
sound indicative of an obstructive event (snoring and/or breathing
difficulty) been sensed? If the answer is no, that no event has
been sensed, then the profile according to 118 continues. Process
120 may be executed during or after the profile defined by 118 is
being executed. If the answer is yes, and an obstructive event is
sensed, then a second pressure profile is applied to mask 6
according to 122. The second profile is referred to as an "incident
profile" and defines a steep or rapid pressure versus time ramp to
aggressively eliminate the obstructive event.
[0062] An exemplary embodiment of the second pressure profile 122
is illustrated with respect to FIG. 9b. During a first portion 122a
of profile 122, the pressure is rapidly ramping from an initial
pressure P3 to a therapeutic pressure P4 while a time progresses
from t5 to t6. Pressure P3 may equal pressure P2 in some cases,
particularly if first pressure profile 118 has reached pressure P2
before second pressure profile 122 begins. A pressure P4 is reached
at time t6. The slope of the pressure ramp defined by portion 122a
is defined by the parameters utilized according to step 114.
Variations on profile 122 are possible. For example, the ramp may
again be non-linear. It may be desirable to have a steeper portion
at the beginning of portion 122a to minimize the time required to
eliminate the obstructive event. Also, the slope of portion 122a
may be determined according to whether the obstructive event is
only snoring versus being a dangerous throat obstruction.
[0063] While the pressure profile of 122 is being applied, the
signal indicative of noise in mask 6 is being monitored. According
to 124, a second decision is made. If the obstructive event
continues to be sensed, then the second therapeutic profile 122
continues.
[0064] If, on the other hand, the obstructive event has stopped (as
a result of the therapeutic profile), then a third pressure profile
is applied according to 126 wherein the applied pressure is
gradually reduced. An exemplary profile 126 is depicted with
respect to FIG. 9c. The pressure applied to mask 6 ramps down from
a higher pressure P6 to a lower pressure P5 that may be equal to or
a little higher than P2 during segment 126a of profile 126. If no
more obstructive events are sensed, the pressure be maintained at
pressure level P5.
[0065] Note that the operating parameters generally define pressure
levels P3, P4, P5, and P6. An exception to this would be if a
change is sensed before a pressure ramp ends. For example, if
according to 124 the obstructive event is no longer sensed before
segment 122a is reaches a maximum therapeutic pressure then
pressure P4 will be determined by the pressure ramp and the
pressure P3 for example. Note that while the flow chart depiction
of FIG. 9 has "steps" such as steps 118 and 120, it is to be
understand that these steps may overlap in time since sensing a
change such as a new obstruction may interrupt the pressure profile
of the previous step.
[0066] According to 128, information indicative of the obstructive
event is stored. According to 130, the information from 128 is
analyzed and a new set of custom operating parameters is generated
in response. Following are some examples of the new set of custom
operating parameters that might be generated.
[0067] As a first example, one or more new a parameters may define
a new initial pressure profile 118 as applied in step 118. From
analyzing the obstructive events, the controller 14 may determine
that the initial profile was insufficient to adequately reduce or
prevent an obstructive event. Thus, for example the new initial
pressure profile would rise to a higher initial operating pressure
level P2. As other examples of parametric changes, the time
duration of segment 118a may be changed or the slope of segment
118b may be changed.
[0068] As a second example, one or more new parameters may define a
new incident pressure profile as applied in step 122. From
analyzing a continuation of the obstructive events, the controller
14 may determine that the incident pressure profile does not rise
aggressively enough to end the obstructive event soon enough. Thus,
the slope of segment 122a may be increased and perhaps a peak
therapeutic pressure P4 may be increased.
[0069] As a third example, one or more new parameters may define a
new third pressure profile 126. For example, the final pressure P5
may be increased or decreased.
[0070] It is possible that a maximum therapeutic pressure defined
by information storage device 18 may not be sufficient to
effectively end obstructive events. If that is the case, then step
124 will continue to determine that an obstructive event is
occurring event when the highest possible level of pressure P4
(same as the maximum allowed therapeutic pressure) has been
reached. In that case therapy device 2 will provide an alarm or
other indication that a new prescription is required. An exemplary
method for providing such a new prescription is further discussed
with respect to FIG. 13.
[0071] An operating method utilizing an external sensor such as a
second microphone 42 is depicted with respect to FIG. 10. According
to step 132, an apnea treatment apparatus 2 configured for home use
is provided to a patient. According to step 134, the apparatus is
operated according to operating parameters stored on information
storage device 18. According to step 136, a signal from microphone
16 internal to mask 6 is monitored. According to step 138, a signal
from microphone 42 external to mask 6 is monitored. According to
step 140, the controller 14 analyzes the signals from 136 and 138
and then generates corrected information indicative of sound being
generated inside mask 6. This can be used to reduce the effects of
noises external to the mask 6 and respiratory system of the patient
who is wearing mask 6.
[0072] An operating method utilizing a digital signature is
depicted with respect to FIG. 11. The analysis of waveforms to
generate "digital signatures" is known. For example, digital
signature methodology is utilized to determine authenticity of
signatures by comparing Fourier transforms of the signature curve
for example.
[0073] According to 142, a sleep apnea treatment apparatus 2
configured for home use is provided to a patient. Sequence 143
includes steps 144-146 and is performed during a first treatment
cycle using apparatus 2. According to 144, a signal indicative of a
sound in mask 6 versus time is monitored. According to 145, the
signal is analyzed to generate a first digital signature. The first
digital signature is then stored on information storage device 18
according to 146.
[0074] Sequence 147 includes steps 148-152 and is performed during
a subsequent second treatment cycle using apparatus 2. According to
148, a second signal indicative of a sound in mask 6 versus time is
monitored. According to 149, the second signal is analyzed to
generate a second digital signature. According to 150, the first
and second digital signatures are compared so as to determine a
match. If a match is determined, then customized operating
parameters may be utilized to control apparatus 2 according to
152.
[0075] The digital signature may be utilized to verify an identity
or condition of a particular patient. For example, during step 146,
the controller 14 may store information on information storage
device indicative of certain operating parameters that are specific
to treating a condition implied by the first digital signature.
[0076] An operating method that is a hybrid between the operating
methods of FIGS. 6 and 8 is depicted with respect to FIG. 12.
According to 154, PAP treatment device 2 is operated according to
operating parameters stored on information storage device 18.
According to 156, a signal derived from one or more of sensors 16
or 38 is monitored. According to 158, the signal is analyzed to
determine whether characteristics of the signal indicative of a
transient condition are present. The controller, in response to
this analysis, generates a decision according to 160. If the
analysis indicates no transient condition, apparatus 2 is operated
using long term optimized operating parameters according to 162.
If, however, a transient condition is detected, then the device is
operated according to 164 wherein operating parameters optimized
for the transient condition are utilized. One clear example of this
operation is the case where congestion is detected (as would be
evidence with a sounds or pressures indicative of congestion).
[0077] As an example of how this might be determined, congestion
would tend to reduce a patient's ability to breath through the
nose. This could be detected by detecting a reduced breath-imparted
flow rate through conduit 8. This would indicate a condition
requiring a decongestant and/or an increased flow rate of an
aerosol from aerosol generator 44. Thus, 164 would include
activating or increasing the activation of aerosol generation
device 44.
[0078] As another example of 164, the PAP therapy device may
provide increased breathing assistance in the event that breathing
difficulties are detected.
[0079] An operating method for determining if the available
pressure range is sufficient is depicted in flow chart form with
respect to FIG. 13. According to 166, a PAP therapy apparatus 2 is
provided to a patient for home use. According to 168, the therapy
apparatus is operated consistent with parameters stored on
information storage device 18. The parameters include an upper
limit defined for an applied therapeutic pressure level. According
to 170, a signal indicative of sound intensity versus time in mask
6 is monitored using sensor 16. As a result of an analysis, a
decision is made according to 172--is there a sufficient parametric
operating margin?
[0080] The parametric operating margin is defined as the difference
between the maximum values for the operating parameters and those
required to prevent or eliminate obstructive events during
operating of treatment apparatus 2. An example of how these
parameters are applied is described with respect to FIG. 9. An
example of an operating parameter is the maximum pressure level. If
the required pressure for treating an obstructive event is close to
or exceeds the maximum allowed pressure, then the parametric
operating margin is insufficient.
[0081] According to 174, if the parametric operating margin is
sufficient, then the current prescribed parameter limits (such as
maximum pressure level, pressure ramp rates, etc.) are sufficient.
If the parametric operating margin is not sufficient, then an
indication is provided that a new prescription is required
according to 176. This could take the form of an alarm provided to
the patient to let the patient know that a prescription is required
via user interface 21. In another embodiment, a web-enabled therapy
device would directly contact the physician to request an updated
prescription.
[0082] The method depicted in FIG. 13 can be used in combination
with the methods described with respect to FIG. 8 or FIG. 9.
Following step 176, the methods of FIG. 7 can then be utilized to
provide new prescription control parameters to the information
storage device 18.
[0083] While various methods have been depicted by flow charts
1-13, it is to be understood that different elements or methods
depicted by different flow charts can be substituted or added from
one flow chart to another.
* * * * *