U.S. patent application number 16/117691 was filed with the patent office on 2019-03-28 for variable mode pulse indicator.
The applicant listed for this patent is Masimo Corporation. Invention is credited to Ammar AL-ALI.
Application Number | 20190090764 16/117691 |
Document ID | / |
Family ID | 39303893 |
Filed Date | 2019-03-28 |
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United States Patent
Application |
20190090764 |
Kind Code |
A1 |
AL-ALI; Ammar |
March 28, 2019 |
VARIABLE MODE PULSE INDICATOR
Abstract
A user configurable variable mode pulse indicator provides a
user the ability to influence outputs indicative of a pulse
occurrence at least during distortion, or high-noise events. For
example, when configured to provide or trigger pulse indication
outputs, a pulse indicator designates the occurrence of each pulse
in a pulse oximeter-derived photo-plethysmograph waveform, through
waveform analysis or some statistical measure of the pulse rate,
such as an averaged pulse rate. When the configured to block
outputs or not trigger pulse indication outputs, a pulse indicator
disables the output for one or more of an audio or visual pulse
occurrence indication. The outputs can be used to initiate an
audible tone "beep" or a visual pulse indication on a display, such
as a vertical spike on a horizontal trace or a corresponding
indication on a bar display. The amplitude output is used to
indicate data integrity and corresponding confidence in the
computed values of saturation and pulse rate. The amplitude output
can vary a characteristic of the pulse indicator, such as beep
volume or frequency or the height of the visual display spike.
Inventors: |
AL-ALI; Ammar; (San Juan
Capistrano, CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Masimo Corporation |
Irvine |
CA |
US |
|
|
Family ID: |
39303893 |
Appl. No.: |
16/117691 |
Filed: |
August 30, 2018 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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14947224 |
Nov 20, 2015 |
10064562 |
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16117691 |
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11871808 |
Oct 12, 2007 |
9192329 |
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14947224 |
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60851861 |
Oct 12, 2006 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61B 5/7405 20130101;
A61B 5/742 20130101; A61B 5/6838 20130101; A61B 5/02427 20130101;
A61B 5/02438 20130101; A61B 5/0002 20130101; A61B 5/6826 20130101;
A61B 5/14551 20130101 |
International
Class: |
A61B 5/024 20060101
A61B005/024; A61B 5/00 20060101 A61B005/00; A61B 5/1455 20060101
A61B005/1455 |
Claims
1.-8. (canceled)
9. A method of configuring output indications of pulse occurrences
in an patient monitor capable of monitoring a pulse rate through a
signal from a noninvasive optical sensor, the method comprising:
receiving an input signal from said sensor; determining a measure
of distortion in said input signal; and when said measure indicates
a high level of distortion, outputting an indication of pulse
occurrences according to user-selected configuration
parameters.
10. The method of claim 9, wherein said indication comprises a
pulse beep.
11. The method of claim 10, wherein said configuration parameters
cause said pulse beep to be blocked.
12. The method of claim 10, wherein said configuration parameters
cause said pulse beep to be responsive to a statistical
representation of a calculated pulse rate.
13. The method of claim 9, wherein said indication comprises visual
display elements.
14. The method of claim 13, wherein said configuration parameters
cause at least one of said display elements to blocked.
15. The method of claim 13, wherein said configuration parameters
cause at least one of said display elements to be responsive to a
statistical representation of a calculated pulse rate.
Description
PRIORITY CLAIM
[0001] This present application claims priority benefit under 35
U.S.C. .sctn. 119(e) from U.S. Provisional Application No.
60/851,861, filed Oct. 12, 2006, entitled "Variable Mode Pulse
Indicator," which is incorporated by reference herein.
CROSS-REFERENCE TO RELATED APPLICATIONS
[0002] The present application is related to U.S. Pat Nos.
6,606,511, 6,002,952, 6,464,311, 6,684,090, 6,770,028, 6,850,788,
and the continuation, continuation-in-part, and divisional
applications thereof. The present application also incorporates the
foregoing disclosures herein by reference.
BACKGROUND OF THE DISCLOSURE
Field of the Disclosure
[0003] The present disclosure relates in general to patient
monitoring and in particular to oximeter patient monitors capable
of monitoring one or more physiological parameters including a
pulse rate from a noninvasive optical sensor.
Description of the Related Art
[0004] A desirable feature of patient monitors, including oximeters
such as oximeters, co-oximeters, and the like, includes at least
one of an audio and video indication of a pulse occurrence
substantially corresponding to a patient's pulse. Such indications
of a pulse occurrence may be caused by a trigger output used to
initiate an audible tone "beep" or a visual pulse indication on a
display.
[0005] In some systems, when signal(s) from a noninvasive optical
sensor include sufficient distortion, high noise, or simply present
low signal quality, pulse indications may be difficult to
calculate. In some systems, the oximeter may simply determine that
no pulse indication is presented to a caregiver.
[0006] In other systems, the oximeter may attempt to determine
pulse occurrences during distortion, high noise, motion-induced
noise, or during low signal quality or confidence. For example, in
U.S. Pat. No. 6,606,511, which is assigned to Masimo Corporation
("Masimo") of Irvine, Calif., which is the assignee of the current
application and incorporated by reference herein, a pulse trigger
output from a rule-based processor is responsive to pulse waveforms
of the patient's oximeter-derived photo-plethysmograph waveform in
low-noise or no-distortion situations. However, during high-noise
or distortion situations, the pulse trigger output may
advantageously become dependent on an average or other statistical
determination of the pulse rate. This "intelligent beep" reliably
indicates the patient's pulse, yet responds to patient arrhythmias,
asystole conditions and similar irregular plethysmographs. An
example of the determination of pulse rate in the presence of
distortion is described in U.S. Pat. Nos. 6,002,952, 6,463,311,
6,684,090, all of which are assigned to Masimo Corporation of
Irvine, Calif., and incorporated by reference herein.
[0007] As disclosed in the '511 patent, when there is relatively no
distortion corrupting a plethysmograph signal, the processor may
analyze the shape of the pulses in the waveform to determine where
in the waveform to generate the pulse indication. When distortion
is present, looser waveform criteria can be used to determine if
pulses are present. For example, when pulses are present, the pulse
indication is based upon an averaged pulse rate. If no pulses are
present, no indication occurs.
[0008] In the disclosed embodiment, the pulse indicator provides a
trigger and amplitude output. The trigger output is used to
initiate an audible tone "beep" or a visual pulse indication on a
display, such as a vertical spike on a horizontal trace, a rising
pulsing or constant bar display, one or more specific colors of a
displayed parameter or trace, one or more LEDs or other visual
elements, combinations of the same, or the like. The amplitude
output is used to indicate data integrity and corresponding
confidence in the computed values of saturation and pulse rate. The
amplitude output can vary a characteristic of the pulse indicator,
such as beep volume or frequency or the height of the visual
display spike.
SUMMARY OF THE DISCLOSURE
[0009] With the acceptance of oximeter systems that output audio
and visual indications of pulse occurrences, caregivers have begun
to rely on assumptions they make from such audio and visual
queries. For example, when a caregiver is accustomed to oximeter
systems that are simply silent during signal distortion,
high-noise, or low signal quality conditions, that caregiver may
make potentially inaccurate assumptions about a patient monitored
by oximeter systems that attempt to find pulse occurrences through
noise. For example, even when an oximeter system includes an output
that adjusts a visual indication of a pulse occurrence to indicate
poor signal conditions or low confidence in determined parameters,
the actuation of an audible beep may lead a caregiver to believe
that the signal conditions, and perhaps the monitored patient, are
better than they actually are. Conversely, a caregiver accustomed
to a monitor that attempts to provide indications of pulse
occurrences through distortion and noise, such as the oximeters
disclosed in the '511 patent, may make potentially inaccurate
assumptions about a patient monitored by oximeter systems that
simply go silent during more difficult signal conditions.
[0010] Based at least thereon, a need exists for a configurable
oximeter that allows caregivers to configure pulse occurrence
indications to match their expectations. Therefore, in an
embodiment of the disclosure, an oximeter includes a variable mode
oximetry pulse indicator responsive to modes selected by a user or
caregiver. For example, one mode may disable audio and visual pulse
occurrence indications, another mode may disable one or the other,
and yet another mode may enable audio and visual pulse occurrence
indications during defined noisy conditions. In an embodiment, the
user may cycle through or otherwise select the particular mode
using user configuration menus and user input devices, such as, for
example, a keypad or other user interface/input device.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] A general architecture that implements the various features
of the disclosure will now be described with reference to the
drawings. The drawings and the associated descriptions are provided
to illustrate embodiments of the disclosure and not to limit its
scope.
[0012] FIGS. 1A-1D illustrate various exemplary oximeter patient
monitoring systems.
[0013] FIG. 2 illustrates an exemplary block diagram of one or more
of the oximeter patient monitoring systems of FIG. 1.
[0014] FIG. 3 illustrates an exemplary user interface providing
user configuration of pulse indicators during signal distortion in
one or more signals acquired from, for example, a non-invasive
optical sensor, according to an embodiment of the disclosure.
[0015] FIG. 4 illustrates exemplary inputs and outputs of a
variable mode oximetry pulse indicator, according to an embodiment
of the disclosure.
[0016] FIG. 5 illustrates an exemplary block diagram of a variable
mode oximetry pulse indicator, according to an embodiment of the
disclosure.
[0017] FIG. 6 illustrates an exemplary block diagram of an
indicator decision module of the variable mode oximetry pulse
indicator of FIG. 5, according to an embodiment of the
disclosure.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0018] Embodiments of the present disclosure include a user
configurable oximetry pulse indicator. For example, a user may
configure whether one or more of audio and visual indicators of
pulse occurrences is presented to a caregiver during, for example,
distortion, motion-induced noise, low signal quality, or other
challenging signal conditions. In an embodiment, a first mode
presents audio and visual indicators of a patient's pulse to a
caregiver during challenging signal conditions, while a second and
third mode presents one or the other respectively, and a fourth
mode blocks or otherwise diminishes the influence of the audio and
visual indicators.
[0019] In an embodiment, an enable signal is generated according to
the user's configurations and a pulse indicator is responsive to
the enable signal. For example, a pulse indicator may
advantageously determine a pulse occurrence and generate an
indicator trigger. Depending upon the particular mode configured by
the user, the pulse indicator trigger, and in some embodiments, a
pulse indicator amplitude may advantageously be forwarded to tone
and display generators. Alternatively, depending upon the
particular mode, the indicator trigger and indicator amplitude may
be partially or entirely blocked or otherwise diminished to match
expectations of the caregiver in challenging signal conditions.
[0020] To facilitate a further understanding of the disclosure, the
remainder of the description describes the invention with reference
to specific drawings. Moreover, in this application, reference may
be made to many blood parameters. Some references that have common
shorthand designations are referenced through such shorthand
designations. For example, as used herein, HbCO designates
carboxyhemoglobin, HbMet designates methemoglobin, Hbt designates
total hemoglobin, SpO.sub.2 designates functional arterial
saturation, and SpaO.sub.2 designates fractional arterial
saturation. Other shorthand designations such as COHb, MetHb, and
tHb are also common in the art for these same constituents. These
constituents are generally reported in terms of a percentage, often
referred to as saturation, relative concentration, concentration,
or fractional saturation. Total hemoglobin is generally reported as
a concentration in g/dL. The use of the particular shorthand
designators presented in this application does not restrict the
term to any particular manner in which the designated constituent
is reported.
[0021] FIG. 1A illustrates a perspective view of a patient monitor
system 100, according to an embodiment of the present disclosure.
The system 100 includes a portable patient monitor 102 capable of
noninvasively determining one or more physiological parameters. In
an embodiment, the portable patient monitor 102 mechanically and
electrically mates with a docking station 104 to recharge
batteries, upload and download information, upgrade software or
firmware, communicate with other monitors or the like. Disclosures
of various docking stations are disclosed with reference to U.S.
Pat. No. 6,770,028, incorporated above.
[0022] FIG. 1A also illustrates the monitor 102 comprising one or
more displays 106 capable displaying of a wide variety of measured
values in a manner that provides for quick and efficient conveyance
of information to a caregiver. For example, the display 106
displays values for HbCO, HbMet, MbT, SpO.sub.2, SpaO.sub.2,
beats-per-minute, scaled plethysmograph data 118, PI.TM. 120 and
other information.
[0023] FIG. 1B illustrates a perspective view of a monitoring
system 150 including a handheld noninvasive multi-parameter patient
monitor 152 communicating with a reusable optical sensor 154
through a patient cable 156, according to embodiments of the
disclosure. In general, the monitor 152 drives the sensor 154 to
emit light of differing wavelengths into the body tissue 158. The
sensor 154 detects the light after attenuation by the body tissue
158 and outputs a signal indicative of the amount of light received
by the sensor 154 through the cable 156. In addition, in some
embodiments, the monitor 152 communicates with a temperature sensor
and a memory device associated with one or more of the sensor 154
and the cable 156, through the cable 156.
[0024] In an embodiment, the monitors 102, 152 receive sensor
output and determine continuous and non-invasive measurements of a
wide variety of blood parameters. Although disclosed with reference
to portable monitors 102, 152, an artisan will recognize from the
disclosure herein that aspects of the present disclosure can be
adopted into tabletop monitors, wireless sensors, or other
patient-wearable personal monitors, or multi-parameter patient
monitors.
[0025] FIG. 1B also shows the sensor 154 comprising a reusable
sensor in the form a clip including a spring biased pivot point
capable of removably attaching the reusable sensor to a patient's
finger 158. Although disclosed with reference to a reusable sensor
having a spring, an artisan will recognize from the disclosure
herein that the sensor 154 can advantageously comprise a disposable
adhesive type sensor, a combination sensor including reusable and
disposable components, components incorporated into other medical
devices such as catheters, or the like, or other reusable sensor
designs. Moreover, the artisan will recognize from the disclosure
herein that the sensor 154 can comprise mechanical structures,
adhesive or other tape structures, Velcro wraps or combination
structures specialized for the type of patient, type of monitoring,
type of monitor, or the like. In an embodiment, the sensor 154
provides data to the monitors 102, 152 and vice versa through the
cable 156, although such communication can advantageously be
wireless, over public or private networks or computing systems or
devices, through intermediate medical or other devices,
combinations of the same, or the like.
[0026] In an embodiment, the monitor 152 includes one or more
displays 160 capable of displaying, for example, one or more of the
foregoing parameters. For example, the display 160 may provide an
indication of HbCO, HbMet, Hbt, SpO.sub.2, SpaO.sub.2, pulse rate,
plethysmographs, historical or trending data, confidence or
perfusion indicators, or the like. The monitors 102, 152 may
include one or more audio, visual or messaging (pagers, emails,
instant and phone messages, vocally presented numbers, messages and
alarms, voice-over-IP ("VOIP") interfaces and functionality, or the
like) alarms, user input keypad 160, or the like.
[0027] Although described in terms of certain embodiments, other
embodiments or combination of embodiments will be apparent to those
of ordinary skill in the art from the disclosure herein. For
example, the monitors 102, 152 may combine other information with
intensity-derived information to influence diagnoses or device
operation. For example, patterns or changes in the continuous
noninvasive monitoring of intensity-derived information may cause
the activation of other vital sign measurement devices, such as,
for example, blood pressure cuffs.
[0028] FIG. 1C illustrates a perspective view of a monitoring
system including a personal or wearable noninvasive multi-parameter
patient monitor 170, according to embodiments of the disclosure.
Such personal oximeters 170 generally wirelessly communicated with
a monitoring station to provide the monitoring station with
measurements for some or all of the physiological parameters
measurable by the monitor. In an embodiment, the monitor travels
with a patient as the patient, for example, moves through a care
site such as a hospital. Wireless networks incorporating such
personal pulse technologies are commercially available from Masimo
marketed under the brand RadNet.TM., RadLink.TM. and Patient Safety
Net.TM..
[0029] FIG. 1D illustrates a perspective view of a monitoring
system including a wireless noninvasive multi-parameter patient
monitor 190, according to embodiments of the disclosure. In an
embodiment, a traditional sensor 192 communicates with a wireless
transmission device 194 wearable, for example, on the wrist. In
other embodiments, the wireless transmission device may
advantageously be incorporated into a sensor housing adapted for
wireless communication. In an embodiment, a wireless receiver 196
communicates with a sensor port 198 in the same manner as a wired
sensor. Thus, in an exemplary embodiment shown in FIG. 1D, a
traditional sensor 192 and a traditional sensor port 198 may be
unaware that a patient cable has been replaced with wireless
transmissions. Disclosure of wireless technologies is disclosed in
U.S. Pat. No. 6,850,788, incorporated by reference herein.
[0030] FIG. 2 illustrates an exemplary block diagram of an
embodiment of a patient monitoring system 200. As shown in FIG. 2,
the system 200 includes a patient monitor 202 comprising a
processing board 204 and a host instrument 208. The processing
board 204 communicates with a sensor 206 to receive one or more
intensity signal(s) indicative of one or more parameters of tissue
of a patient. The processing board 204 also communicates with a
host instrument 208 to display determined parameter values
calculated using the one or more intensity signals. According to an
embodiment, the board 204 comprises processing circuitry arranged
on one or more printed circuit boards capable of installation into
the monitor 202, or capable of being distributed as some or all of
one or more OEM components for a wide variety of host instruments
monitoring a wide variety of patient information. In an embodiment,
the processing board 202 comprises a sensor interface 210, a
digital signal processor and signal extractor ("DSP" or
"processor") 212, and an instrument manager 214. In general, the
sensor interface 210 converts digital control signals into analog
drive signals capable of driving sensor emitters, and converts
composite analog intensity signal(s) from light sensitive detectors
into digital data.
[0031] In an embodiment, the sensor interface 210 manages
communication with external computing devices. For example, in an
embodiment, a multipurpose sensor port (or input/output port) is
capable of connecting to the sensor 206 or alternatively connecting
to a computing device, such as a personal computer, a PDA,
additional monitoring equipment or networks, or the like. When
connected to the computing device, the processing board 204 may
upload various stored data for, for example, off-line analysis and
diagnosis. The stored data may comprise trend data for any one or
more of the measured parameter data, plethysmograph waveform data
acoustic sound waveform, or the like. Moreover, the processing
board 204 may advantageously download from the computing device
various upgrades or executable programs, may perform diagnosis on
the hardware or software of the monitor 202. In addition, the
processing board 204 may advantageously be used to view and examine
patient data, including raw data, at or away from a monitoring
site, through data uploads/downloads, or network connections,
combinations, or the like, such as for customer support purposes
including software maintenance, customer technical support, and the
like.
[0032] As shown in FIG. 2, the digital data is output to the DSP
212. According to an embodiment, the DSP 212 comprises a processing
device based on the Super Harvard ARChitecture ("SHARC"), such as
those commercially available from Analog Devices. However, a
skilled artisan will recognize from the disclosure herein that the
DSP 212 can comprise a wide variety of data and/or signal
processors capable of executing programs for determining
physiological parameters from input data. In particular, the DSP
212 includes program instructions capable of receiving multiple
channels of data related to one or more intensity signals
representative of the absorption (from transmissive or reflective
sensor systems) of a plurality of wavelengths of emitted light by
body tissue. In an embodiment, the DSP 212 accepts data related to
the absorption of two (2) to eight (8) wavelengths of light,
although an artisan will recognize from the disclosure herein that
the data can be related to the absorption of two (2) to sixteen
(16) or more wavelengths.
[0033] FIG. 2 also shows the processing board 204 including the
instrument manager 214. According to an embodiment, the instrument
manager 214 may comprise one or more microcontrollers controlling
system management, including, for example, communications of
calculated parameter data and the like to the host instrument 208.
The instrument manager 214 may also act as a watchdog circuit by,
for example, monitoring the activity of the DSP 212 and resetting
it when appropriate.
[0034] The sensor 206 may comprise any commercially available
noninvasive oximetry sensor. In an embodiment, the sensor 206
provides data to the board 204 and vice versa through, for example,
a patient cable. An artisan will also recognize from the disclosure
herein that such communication can be wireless, over public or
private networks or computing systems or devices, or the like.
[0035] As shown in FIG. 2, the sensor 206 includes a plurality of
emitters 216 irradiating the body tissue 218 with differing
wavelengths of light, and one or more detectors 220 capable of
detecting the light after attenuation by the tissue 218. The sensor
206 may also include other electrical components such as, for
example, a memory device 222 comprising an EPROM, EEPROM, ROM, RAM,
microcontroller, combinations of the same, or the like. In an
embodiment, other sensor components may include a temperature
determination device 223 or other mechanisms for, for example,
determining real-time emission wavelengths of the emitters 216.
[0036] The memory 222 may advantageous store some or all of a wide
variety data and information, including, for example, information
on the type or operation of the sensor 206; type or identification
of sensor buyer or distributor or groups of buyer or distributors,
sensor manufacturer information, sensor characteristics including
the number of emitting devices, the number of emission wavelengths,
data relating to emission centroids, data relating to a change in
emission characteristics based on varying temperature, history of
the sensor temperature, current, or voltage, emitter
specifications, emitter drive requirements, demodulation data,
calculation mode data, the parameters for which the sensor is
capable of supplying sufficient measurement data (e.g., HpCO,
HpMet, Hbt, or the like), calibration or parameter coefficient
data, software such as scripts, executable code, or the like,
sensor electronic elements, whether the sensor is a disposable,
reusable, multi-site, partially reusable, partially disposable
sensor, whether it is an adhesive or non-adhesive sensor, whether
the sensor is a reflectance, transmittance, or transreflectance
sensor, whether the sensor is a finger, hand, foot, forehead, or
ear sensor, whether the sensor is a stereo sensor or a two-headed
sensor, sensor life data indicating whether some or all sensor
components have expired and should be replaced, encryption
information, keys, indexes to keys or hash functions, or the like,
monitor or algorithm upgrade instructions or data, some or all of
parameter equations, information about the patient, age, sex,
medications, and other information that may be useful for the
accuracy or alarm settings and sensitivities, trend history, alarm
history, or the like. In an embodiment, the monitor may
advantageously store data on the memory device, including, for
example, measured trending data for any number of parameters for
any number of patients, or the like, sensor use or expiration
calculations, sensor history, or the like.
[0037] FIG. 2 also shows the patient monitor 202 including the host
instrument 208. In an embodiment, the host instrument 208
communicates with the board 204 to receive signals indicative of
the physiological parameter information calculated by the DSP 212.
The host instrument 208 preferably includes one or more display
devices 224 capable of displaying indicia representative of the
calculated physiological parameters of the tissue 218 at the
measurement site including for example pulse occurrence indicia In
an embodiment, the host instrument 208 may advantageously comprise
a handheld housing capable of displaying parameter data, including
but not limited to pulse rate, plethysmograph data, perfusion
quality such as a perfusion quality index ("PI.TM."), signal or
measurement quality ("SQ"), values of blood constituents in body
tissue, including for example, SpO.sub.2, HbCO, HbMet, Hbt, or the
like. In other embodiments, the host instrument 208 is capable of
displaying values for one or more of Hbt, Hb, blood glucose,
bilirubin, or the like. The host instrument 208 may be capable of
storing or displaying historical or trending data related to one or
more of the measured values, combinations of the measured values,
plethysmograph data, or the like. The host instrument 208 also
includes an audio indicator 226 and user input device 228, such as,
for example, a keypad, touch screen, pointing device, voice
recognition device, or the like.
[0038] In still additional embodiments, the host instrument 208
includes audio or visual alarms that alert caregivers that one or
more physiological parameters are falling below predetermined safe
thresholds. The host instrument 208 may include indications of the
confidence a caregiver should have in the displayed data. In a
further embodiment, the host instrument 208 may advantageously
include circuitry capable of determining the expiration or overuse
of components of the sensor 206, including, for example, reusable
elements, disposable elements, or combinations of the same.
[0039] The monitor 202 also includes a mode configuration 211
accessible to the DSP 212 and responsive to inputs from, for
example, the user input device 218. The mode configuration
advantageously provides a caregiver the ability to configure pulse
indicators in low signal quality conditions.
[0040] Although described in terms of certain embodiments, other
embodiments or combination of embodiments will be apparent to those
of ordinary skill in the art from the disclosure herein. For
example, the monitor 202 may comprise one or more monitoring
systems monitoring parameters, such as, for example, vital signs,
blood pressure, ECG or EKG, respiration, glucose, bilirubin, or the
like. Such systems may combine other information with
intensity-derived information to influence diagnosis or device
operation. Moreover, the monitor 202 may advantageously include an
audio system, preferably comprising a high quality audio processor
and high quality speakers to provide for voiced alarms, messaging,
or the like. In an embodiment, the monitor 202 may advantageously
include an audio out jack, conventional audio jacks, headphone
jacks, or the like, such that any of the display information
disclosed herein may be audiblized for a listener. For example, the
monitor 202 may include an audible transducer input (such as a
microphone, piezoelectric sensor, or the like) for collecting one
or more of heart sounds, lung sounds, trachea sounds, or other body
sounds and such sounds may be reproduced through the audio system
and output from the monitor 202. Also, wired or wireless
communications (such as Bluetooth or WiFi, including IEEE 801.11a,
b, or g), mobile communications, combinations of the same, or the
like, may be used to transmit the audio output to other audio
transducers separate from the monitor 202. Moreover, patterns or
changes in the continuous noninvasive monitoring of
intensity-derived information may cause the activation of other
vital sign measurement devices, such as, for example, blood
pressure cuffs.
[0041] FIG. 3 illustrates an exemplary user interface 300 providing
user configuration of pulse indicators during signal distortion,
according to an embodiment of the disclosure. In an embodiment, a
user interacts with a user input device to configure certain
behaviors of the patient monitor, including configuration of the
audio and visual pulse indicators. As shown in FIG. 3, the
interface 300 includes selectable or configurable parameters for
one or both of the audible and visual pulse indicators 302, 304,
respectively. For example, a user may determine that unless the
instrument receives a strong signal quality, the user does not want
to hear pulse indications; however, the user may want the visual
indications to remain for purposes of trending, marking, closer
inspection, diagnosis, or the like. In such case, the user may
advantageously select "NO" 306 for the audio pulse indication
configuration 302 and select "YES" 308 for the visual pulse
indication configuration 304.
[0042] Although disclosed with reference to individual
configuration of audio and visual pulse indications during low
signal quality or confidence, an artisan will recognize from the
disclosure herein a wide variety of user configurations as varying
levels of detail to allow a user to customize the response of the
patient monitor to varying signal quality. For example, the
interface 300 may include configuration of modes governing the use
of the pulse indicator amplitude for audio and visual indicators,
configuration settings for a wide variety of differing audio and
visual indications, such as, for example, coloring, trace
characteristics, plethysmograph characteristics, trending
characteristics, memory storage, varying frequencies, volume, voice
messages, paging, other alarming, configuring the behavior of a bar
graph, LED train, or the like.
[0043] FIG. 4 illustrates exemplary inputs and outputs of a
variable mode oximetry pulse indicator 400, according to an
embodiment of the disclosure. In an embodiment, the indicator 400
can be incorporated into an oximeter to trigger the occurrence of a
synchronous indication of each of the patient's arterial pulses.
The indicator 400 operates on, for example, an IR signal input 402
and generates an audio trigger output 404, a visual trigger output
406, and an amplitude output 408. The output 404 can be connected
to a tone generator within the oximeter monitor 202 to create, for
example, a fixed-duration audible "beep" as a pulse indication.
Alternatively, or in addition, the output 406 can be connected to a
display generator within the oximeter monitor 202 to create one or
more visual pulse indications. The visual pulse indications can
include a continuous horizontal trace on a CRT, LCD display or
similar display device, where vertical spikes occur in the trace
synchronously with the patient's pulse. The visual pulse
indications may also include a bar display, such as a vertically-
or horizontally-arranged stack of LEDs or similar display device,
where, for example, the bar pulses synchronously with the patient's
pulse. The visual indications may include changing colors, textual
or graphical information, trace data, plethysmograph data, or the
like. In an embodiment, an enable signal 410 responsive to the mode
configuration 211 of FIG. 4, dictates whether all, some, or none of
the outputs 404, 406 and 408 are output to the audio and visual
mechanisms of the host instrument 208.
[0044] FIG. 4 also shows the amplitude output 408 used to vary one
or more of the audible or visual indications so as to designate
input data integrity and a corresponding confidence in the
parameter and pulse rate outputs of the oximeter. For example, the
height of a vertical spike can be varied in proportion to the
amplitude output 408, where a large or small vertical spike would
correspondingly designate high or low confidence. As another
example, the amplitude output 408 can be used to vary the volume of
the audible beep or to change the visual indication (e.g., change
color or the like) to similarly designate a high or low confidence.
One of ordinary skill in the art will recognize that the trigger
outputs 404, 406 and amplitude output 408 can be utilized to
generate a variety of audible and visual indications of a patient's
pulse and data integrity within the scope of this disclosure.
[0045] Other inputs to the variable mode pulse indicator 400
include pulse rate 412, Integ (data integrity) 414, PR (pulse rate)
density 416, patient type 418 and reset 420, which are described in
detail in U.S. Pat. No. '511, referenced in the foregoing. The
trigger decisions involve rule-based processes that advantageously
respond to the pulse waveforms of the patient's plethysmograph in
low-noise or no-distortion situations. However, the trigger
decisions may become dependent on the configuration parameters to
determine what, if any, outputs occur and how those outputs will be
audio and/or visually communicated to a caregiver.
[0046] The pulse rate input 412 to the pulse indicator 400 provides
the frequency of the patient's pulse rate in beats per minute.
Pulse rate can be determined as described in U.S. patent
application Ser. No. 08/834,194 or U.S. Patent Application entitled
"Plethysmograph Pulse Recognition Processor," both cited above. The
Integ output 414 is a measure of the integrity of the IR 402 and
Red input signals. In an embodiment, the measure is derived from
signals from the sensor 206 as processed by an adaptive noise
canceller. The PR density input 416 may comprise a ratio of the sum
of the periods of recognizable pulses within a waveform segment
divided by the length of the waveform segment. This parameter
represents the fraction of the waveform segment that can be
classified as having physiologically acceptable pulses. In one
embodiment, a segment represents a snapshot of 400 samples of a
filtered input waveform, or a 6.4 second "snapshot" of the IR
waveform at a 62.5 Hz sampling rate. The derivation of Integ output
414 and PR density is described in U.S. Pat. No. 6,464,311 entitled
"Plethysmograph Pulse Recognition Processor," and cited above. The
patient type 418 comprises a Boolean value that indicates either an
adult sensor or a neonate sensor is in use. The reset 420
initializes the state of the pulse indicator 400 to known values
upon power-up and during periods of recalibration, such as when a
new sensor is attached or a patient cable is reconnected.
[0047] FIG. 5 illustrates an exemplary functional block diagram of
a variable mode oximetry pulse indicator 400, according to an
embodiment of the disclosure. As shown in FIG. 5, the indicator 400
includes a shifting buffer 510, a distortion level function 520, a
waveform analyzer 530, and an indicator decision 540, which
together produce the indicator triggers 404, and 406. The pulse
indicator 400 also includes a scaled logarithm function 550 that
produces the indicator amplitude output 408. The shifting buffer
510 accepts the IR input 402 and provides a vector output 512
representing a fixed-size segment of the patient's plethysmograph
input to the waveform analyzer 530. The distortion level function
520 determines the amount of distortion present in the IR input
signal 402. The inputs to the distortion level function 520 are the
Integ input 414 and the PR density input 416. The distortion output
522 is a Boolean value that is "true" when distortion in the IR
input 402 is above a predetermined threshold. The distortion output
522 is input to the waveform analyzer 530 and the indicator
decision 540. The distortion output 522 determines the thresholds
for the waveform analyzer 530. The distortion output 522 also
affects the window size within which a pulse indication can occur.
The distortion output 522 is also a function of the patient type
input 418, which indicates whether the patient is an adult, a
neonate, or the like.
[0048] In general, the waveform analyzer 530 determines whether a
particular portion of the IR input 402 is an acceptable place for a
pulse indication. The input to the waveform analyzer 530 is the
vector output 512 from the shifting buffer 510, creating a waveform
segment. A waveform segment portion meets the acceptance criteria
for a pulse when it satisfies one of three conditions. These
conditions are a sharp downward edge, a peak in the middle with
symmetry with respect to the peak, and a peak in the middle with a
gradual decline. If one of these criteria is met, the waveform
analyzer "quality" output 532 is "true." Different criteria are
applied depending on the state of the distortion output 522, which
is also a waveform analyzer input. If the distortion output 522
indicates no distortion, strict criteria are applied to the
waveform shape. If the distortion output 522 indicates distortion,
looser criteria are applied to the waveform shape. Different
criteria are also applied for waveforms obtained from adult and
neonate patients, as indicated by the patient type 406.
[0049] The indicator decision 540 determines whether to trigger a
pulse indication at a particular sample point of the input
waveform. Specifically, the indicator decision 540 determines, in
conjunction with the mode configuration 211, whether to, and if it
is the right place to, trigger a pulse indication. The decision as
to whether to trigger the pulse indication is configured by the
user through the mode configuration 211. The enable signal 410 is
responsive to the mode configuration 211, and, in the case one or
both of the distortion and quality signals 522 and 532 indicating
poor signal quality, the indicator decision 540 determines whether
some, all, or none of the audio and visual triggers 404 will pass
to the audio and display devices of the host instrument 208. In an
embodiment, the enable signal 410 may comprise Boolean high and low
signals and the mode selector may comprise logical gates configured
to pass or block signals based on the enable signal 410.
[0050] In addition to the enable signals 410, the decision as to
the right place to trigger a pulse indication is a function of the
analyzer output 532, which is one input to the indicator decision
540. The decision as to the right time for an indicator trigger is
a function of the state of the distortion output 522, which is
another input to the indicator decision 540. If the distortion
output 522 is "false", i.e. no distortion is detected in the input
waveform, then a fixed minimum time gap from the last indicator
must occur. In a particular embodiment, this minimum time gap is 10
samples. If the distortion output 522 is "true", i.e. distortion is
detected in the input waveform, then the minimum time gap is a
function of the pulse rate input 412. Additional details are
disclosed in co-owned U.S. Pat. No. '511, referenced in the
foregoing.
[0051] FIG. 6 illustrates an exemplary block diagram of the
indicator decision module 540 of the variable mode oximetry pulse
indicator 400 of FIG. 5, according to an embodiment of the
disclosure. As shown in FIG. 6, a first stage 602 of the indicator
decision 640 determines a minimum time gap after which a pulse
indicator can occur. The second stage 604 determines whether the
number of samples since the last indicator is greater than the
minimum allowed pulse gap. The third stage 606 decides whether to
generate a pulse indicator trigger. If no trigger occurs, a sample
count is incremented. If an indicator trigger occurs, the sample
count is reset to zero.
[0052] The first stage 602 has a divider 610, a truncation 620 and
a first multiplexer 630. These components function to set the
minimum allowable gap between pulse indications. Under no
distortion, the minimum gap is 10 samples. Under distortion, the
gap is determined by the pulse rate. Specifically, under
distortion, the minimum gap is set at about 80% of the number of
samples between pulses as determined by the pulse rate input 402.
This may be computed as about 0.8 times the sample frequency, such
as, for example, 62.5 Hz., divided by the pulse rate in pulses per
second.
[0053] The divider 610 computes 3000/pulse rate. The divider output
612 is truncated 620 to an integer value. The first multiplexer 630
selects the minimum gap as either 10 samples if the distortion
input 622 is "false" or the truncated value of 3000/pulse rate if
the distortion input 622 is "true." The selected value is provided
on the multiplexer output 632, which is fed to the second stage
604. The second stage 604 is a comparator 640, which provides a
Boolean output 642 that is "true" if a counter output 652 has a
value that is equal to or greater than the minimum gap value
provided at the first multiplexer output 632.
[0054] FIG. 6 also illustrates the third stage 606, which has a
counter and one or more mode selector function. The counter
comprises a delay element 650 providing the counter output 652, an
adder 660 and a second multiplexer 670. When the counter is
initialized, the second multiplexer 670 provides a zero value on
the multiplexer output 672. The multiplexer output 672 is input to
the delay element, which delays the multiplexer output value by one
sample period before providing this value at the counter output
652. The counter output 652 is incremented by one by the adder 660.
The adder output 662 is input to the second multiplexer 662, which
selects the adder output 662 as the multiplexer output 672 except
when the counter is initialized, as described above. The counter is
initialized to zero when the pulse indicator trigger 404, 406 are
"true" as determined by the output of the mode selectors 680.
[0055] The mode selectors 680 include inputs of the quality 532,
the distortion 522, the enable signal 410, and the output of the
comparator 642, and respectively outputs the triggers 404, 406. In
an embodiment, the mode selectors 680 each comprise a logical
combination of the input signals to determine the output signal.
For example, a mode selector 680 may advantageously logically "OR"
the quality and distortion signals 532, 522, respectively, and
logically "AND" that output with the enable signal 410, and the
comparator output 642. In such an embodiment, when either the
quality signal 532 or the distortion signal 522 indicates less than
ideal qualities in the input IR signal 402, the mode configuration
211 governs whether the output signals 404, 406 are triggered.
Other embodiments could logically "AND" all the signals to require
both the quality signal 532 and the distortion signal 522 to
indicate poor signal quality from the sensor before the mode
configuration 211 takes over. In still other embodiments, the
logical combinations could be part of the mode configuration and
the user may control how the signal are combined to determine
whether to trigger one or more of the output signals 404, 406.
Moreover, an artisan will recognize from the disclosure herein a
number of logical combinations of input signals that allow the mode
configuration 211 to dictate the behavior of a patient monitor with
respect to at least the pulse indications when the signal quality
is less than ideal.
[0056] While variable mode pulse indicator has been described,
other embodiments of the present disclosure will be known to those
of skill in the art from the descriptions herein. Moreover, those
of skill in the art understand that information and signals can be
represented using a variety of different technologies and
techniques. For example, data, instructions, commands, information,
signals, bits, symbols, and chips that can be referenced throughout
the above description may be represented by voltages, currents,
electromagnetic waves, magnetic fields or particles, optical fields
or particles, or any combination thereof.
[0057] Those of skill in the art further appreciate that the
various illustrative logical blocks, modules, circuits, and
algorithm steps described in connection with the embodiments
disclosed herein can be implemented as electronic hardware,
computer software, or combinations of both. To illustrate this
interchangeability of hardware and software, various illustrative
components, blocks, modules, circuits, and steps have been
described above generally in terms of their functionality. Whether
such functionality is implemented as hardware or software depends
upon the particular application and design constraints imposed on
the overall system. Skilled artisans can implement the described
functionality in varying ways for each particular application, but
such implementation decisions should not be interpreted as causing
a departure from the scope of the present invention.
[0058] The various illustrative logical blocks, modules, and
circuits described in connection with the embodiments disclosed
herein can be implemented or performed with a general purpose
processor, a digital signal processor (DSP), an application
specific integrated circuit (ASIC), a field programmable gate array
(FPGA) or other programmable logic device, discrete gate or
transistor logic, discrete hardware components, or any combination
thereof designed to perform the functions described herein. A
general purpose processor can be a microprocessor, but in the
alternative, the processor can be any conventional processor,
controller, microcontroller, or state machine. A processor can also
be implemented as a combination of computing devices, e.g., a
combination of a DSP and a microprocessor, a plurality of
microprocessors, one or more microprocessors in conjunction with a
DSP core, or any other such configuration.
[0059] The steps of a method or algorithm described in connection
with the embodiments disclosed herein can be embodied directly in
hardware, in a software module executed by a processor, or in a
combination of the two. A software module can reside in RAM memory,
flash memory, ROM memory, EPROM memory, EEPROM memory, registers,
hard disk, a removable disk, a CD-ROM, or other form of storage
medium known in the art. A storage medium is coupled to the
processor, such that the processor can read information from, and
write information to, the storage medium. In the alternative, the
storage medium can be integral to the processor. The processor and
the storage medium can reside in an ASIC. The ASIC can reside in a
user terminal, physiological monitor and/or sensor. The processor
and the storage medium can reside as discrete components in a user
terminal, physiological monitor and/or sensor.
[0060] Although the foregoing disclosure has been described in
terms of certain preferred embodiments, other embodiments will be
apparent to those of ordinary skill in the art from the disclosure
herein. Additionally, other combinations, omissions, substitutions
and modifications will be apparent to the skilled artisan in view
of the disclosure herein. Moreover, it is contemplated that various
aspects and features of the invention described can be practiced
separately, combined together, or substituted for one another, and
that a variety of combination and subcombinations of the features
and aspects can be made and still fall within the scope of the
invention. Furthermore, the systems described above need not
include all of the modules and functions described in the preferred
embodiments. Accordingly, the present invention is not intended to
be limited by the recitation of the preferred embodiments, but is
to be defined by reference to the appended claims.
[0061] Additionally, all publications, patents, and patent
applications mentioned in this specification are herein
incorporated by reference to the same extent as if each individual
publication, patent, or patent application was specifically and
individually indicated to be incorporated by reference.
* * * * *