Monitoring Device for Measuring
Content
US 20070073178Al
(19) United States (12) Patent Application Publication (10) Pub. No.: US 2007/0073178 A1
Browning et al.
(54) MONITORING DEVICE FOR MEASURING
CALORIE EXPENDITURE
(43) Pub. Date:
Mar. 29, 2007
Publication Classi?cation
(51)
(75) Inventors: Ray Browning, Denver, CO (US); Christopher Hall, San Francisco, CA
(US); Matthew Banet, Del Mar, CA
Int. Cl. A61B 5/04
Us. or.
(2006.01)
(52)
............................................................ .. 600/519
(Us)
Correspondence Address:
MCDONNELL BOEHNEN HULBERT & BERGHOFF LLP 300 S. WACKER DRIVE 32ND FLOOR
(57)
ABSTRACT
The invention provides a monitoring device that features: 1)
a cardiac sensor component With at least one light-emitting
diode and a photodetector; 2) a pedometer component With
at least one motion-sensing component (e.g., an accelerom eter); and 3) a Wireless component With a Wireless interface that communicates With an external Weight scale. The device also features a microprocessor in electrical communication With the cardiac sensor, pedometer, and Wireless compo
CHICAGO, IL 60606 (US)
(73) Assignee: Berkeley HeartLab, Inc.
(21) Appl. No.:
(22) Filed:
11/522,565
Sep. 18, 2006
nents and con?gured to analyze: l) a signal from the cardiac
sensor component to generate heart rate information; 2) a
signal from the pedometer component to generate exercise
information; 3) heart rate and exercise information to gen erate calorie information; and 4) a signal from the external
Related US. Application Data
(60) Provisional application No. 60/72l,665, ?led on Sep. 29, 2005.
Weight scale to calculate Weight information (e.g., Weight
and percent body fat).
Patent Application Publication Mar. 29, 2007 Sheet 1 0f 6
US 2007/0073178 A1
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US 2007/0073178 A1
Mar. 29, 2007
MONITORING DEVICE FOR MEASURING CALORIE EXPENDITURE CROSS REFERENCES TO RELATED APPLICATION
from the cardiac sensor component to generate heart rate
information; 2) a signal from the pedometer component to generate exercise information; 3) heart rate and exercise information to generate calorie information; and 4) a signal from the external Weight scale to calculate Weight informa
[0001] This application claims the bene?t of US. Provi sional Application Ser. No. 60/721,665 ?led on Sep. 29,
tion (e.g., Weight and percent body fat). The monitoring
device also includes a transmitting component (eg a serial port or Wireless interface) that transmits the heart rate, exercise, calorie, and Weight information to an external device, such as a personal computer connected to the Inter
net.
2005 and is hereby incorporated by reference.
BACKGROUND OF THE INVENTION
[0002]
1. Field of the Invention
[0008] In embodiments, the microprocessor is con?gured
to operate a computer algorithm that processes the heart rate and exercise information to generate calorie information, such as calories burned. For example, the algorithm can
[0003] The present invention relates to medical devices for monitoring information, such as heart rate and calories burned, from a subject.
[0004] 2. Description of the Related Art
[0005] Pedometers are common devices that typically
include a motion-sensitive component, such as an acceler
process the physical activity information to determine
Whether a subject is at rest or undergoing exercise, and once this is determined compare the heart rate information to pre-determined calibration information to determine an
ometer or a tilt sWitch, that typically generates an analog
amount of calories burned by the subject. More speci?cally,
the calibration information can include a predetermined data table or mathematical function that correlates oxygen con sumed as a function of heart rate. The algorithm can then
voltage that peaks in response to motion (e.g., steps). A microcontroller can receive the analog voltage, digitiZe it,
and then process it by counting the peaks to determine a
subject’s steps. Heart rate monitors are also common
devices that measure a subject’s heart rate, typically by
calculate caloric expenditure from the amount of oxygen consumed.
measuring a biometric signal (i.e., by processing an electri
cal signal collected by an electrode, such as that used in an
[0009] The invention has many advantages, particularly in
providing a small-scale, loW-cost device that rapidly mea
sures health-related indicators such as blood pressure, heart
ECG) or an optical plethysmograph (i.e., by processing an
optical signal collected by a pulse oximeter).
[0006] Pulse oximeters are typically Worn on a patient’s ?nger or ear lobe, and feature a processing module that
rate, and blood oxygen content. In embodiments, the device makes blood pressure measurements Without using a culf in
a matter of seconds, meaning patients can easily monitoring
device this property With minimal discomfort. In this Way the monitoring device combines all the bene?ts of conven
analyZes data generated by an optical module. The optical
module typically includes ?rst and second light sources
(e.g., light-emitting diodes, or LEDs) that transmit optical radiation at, respectively, red (7»~630-670 nm) and infrared (7»~800-l200nm) Wavelengths. The optical module also fea
tures a photodetector that detects radiation transmitted or
tional blood-pressure measuring devices Without any of the
obvious draWbacks (e.g., restrictive, uncomfortable culfs).
Its measurement, made With an optical ‘pad sensor’, is basically unobtrusive to the patient, and thus alleviates conditions, such as a poorly ?tting culf, that can erroneously affect a blood-pressure measurement. Ultimately this alloWs patients to measure their vital signs throughout the day (e. g., While at Work), thereby generating a complete set of infor mation, rather than just a single, isolated measurement.
Physicians can use this information to diagnose a Wide
re?ected by an underlying artery. Typically the red and infrared LEDs sequentially emit radiation that is partially absorbed by blood ?oWing in the artery. The photodetector
is synchroniZed With the LEDs to detect transmitted or
re?ected radiation. In response, the photodetector generates a separate radiation-induced signal for each Wavelength. The signal, called a plethysmograph, is an optical Waveform that
varies in a time-dependent manner as each heartbeat varies
variety of conditions, particularly hypertension and its many
related diseases.
the volume of arterial blood, and hence the amount of transmitted or re?ected radiation. A microprocessor in the
[0010]
The device additionally includes a simple Wired or
pulse oximeter processes the relative absorption of red and
infrared radiation to determine the oxygen saturation in the
patient’s blood. Anumber betWeen 94%-l00% is considered normal, While a value beloW 85% typically indicates the
Wireless interface that sends vital-sign information to a personal computer. For example, the device can include a Universal Serial Bus (USB) connector that connects to the
computer’s back panel. Once a measurement is made, the
device stores it on an on-board memory and then sends the
patient requires hospitaliZation.
SUMMARY OF THE INVENTION
[0007]
In one aspect the invention provides a monitoring
device that features: 1) a cardiac sensor component With at least one LED and a photodetector; 2) a pedometer compo nent With at least one motion-sensing component (e.g., an accelerometer); and 3) a Wireless component With a Wireless interface that communicates With an external Weight scale. The device also features a microprocessor in electrical
information through the USB port to a softWare program running on the computer. Alternatively, the device can include a short-range radio interface (based on, e.g., Blue toothTM or 802.154) that Wirelessly sends the information to a matched short-range radio Within the computer. The soft Ware program running on the computer then analyZes the information to generate statistics on a patient’s vital signs
(e.g., average values, standard deviation, beat-to-beat varia
tions) that are not available With conventional devices that make only isolated measurements. The computer can then send the information through a Wired or Wireless connection to a central computer system connected to the Internet.
communication With the cardiac sensor, pedometer, and
Wireless components and con?gured to analyZe: l) a signal
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[0011]
The central computer system can further analyze
blood pressure, pulse oximetry, heart rate, glucose levels,
calories burned and steps traveled from a patient 1. The
the information, eg display it on an Internet-accessible Website. This means medical professionals can characterize
a patient’s real-time vital signs during their day-to-day
activities, rather than rely on an isolated measurement
monitoring device 5, typically Worn on the patient’s belt 13, features: i) an integrated, optical ‘pad sensor’6 that culf lessly measures blood pressure, pulse oximetry, and heart
rate from a patient’s ?nger as described in more detail
during a medical check-up. The Website typically features
one or more Web pages that display the blood test, vital sign,
beloW; and ii) an integrated pedometer circuit 9 that mea
sures steps and, using one or more algorithms, calories
exercise, and personal information. In embodiments, the
Website includes a ?rst Web interface that displays informa tion for a single patient, and a second Web interface that displays information for a group of patients. For example, a
medical professional (eg a physician, nurse, nurse practi tioner, dietician, or clinical educator) associated With a group of patients could use the second Web interface to drive compliance for a disease-management program. Both Web
burned. To receive information from external devices, the monitoring device 5 also includes: i) a serial connector 3 that connects and doWnloads information from an external glu cometer 22; and ii) a short-range Wireless transceiver 7 that receives information such as body Weight and percentage of body fat from an external scale 21. The patient vieWs
information from a liquid crystal display (LCD) display 4
mounted on the monitoring device 5, and can interact With the monitoring device 5 (e.g., reset or reprogram it) using a
interfaces typically include multiple Web pages that, in turn,
feature both static and dynamic content, described in detail beloW.
[0012] The Website can also include a messaging engine that processes real-time information collected from the device to, among other things, help a patient comply With a
disease-management program, such as a personaliZed car
series of buttons 8a, 8b.
[0022] The monitoring device can be used for a variety of
applications relating to, e.g., disease management, health maintenance, and medical diagnosis.
[0023] FIG. 2 shoWs a preferred embodiment of an Inter net-based system 36 that operates in concert With the small scale monitoring device 5 to send information from the
patient 11 to an Internet-accessible Website 33. There, a user can access the information using a conventional Web
diovascular risk reduction program. The messaging engine
analyses blood test, vital sign, exercise, and personal infor
mation, taken alone or combined, to generate personaliZed, patient-speci?c messages. Ultimately the Internet-based sys
tem, monitoring device, and messaging engine combine to
form an interconnected, easy-to-use tool that can engage the
broWser through a patient interface 15 or a physician inter
patient in a disease-management program, encourage fol
loW-on medical appointments, and build patient compliance.
These factors, in turn, can help the patient loWer their risk
for certain medical conditions.
face 34. Typically the patient interface 15 shoWs information from a single user, Whereas the physician interface 34 displays information for multiple patients. In both cases, information ?oWs from the monitoring device 5 through a
USB cable 10 to an external device, e.g., a personal com
[0013] These and other advantages of the invention Will be apparent from the folloWing detailed description and from
the claims.
BRIEF DESCRIPTION OF THE DRAWINGS [0014] FIG. 1A is a semi-schematic vieW of a portable, small-scale monitoring device that measures blood pressure,
puter 30. The personal computer 30 connects to the Internet 31 through a Wired gateWay softWare system 32, such as an Internet Service Provider.
[0024] In other embodiments, the small-scale monitoring device 5 transmits patient information using a short-range
Wireless transceiver 7 through a short-range Wireless con
pulse oximetry, heart rate, glucose levels, Weight, steps
traveled, and calories burned;
[0015] FIG. 1B is a semi-schematic vieW of the monitor ing device of FIG. 1A Worn on a patient’s belt;
[0016] FIG. 2 is a schematic vieW of an Internet-based
nection 37 (e.g., BluetoothTM, 80215.4, part-l5) to the personal computer 30. For example, the small-scale moni
toring device 5 can transmit to a matched transceiver 12
Within (or connected to) the personal computer 30.
[0025] During typical operation, the patient 11 uses the
monitoring device 5 for a period of time ranging from a l-3 months. Typically the patient 11 takes measurements a feW
system that receives information from the monitoring device of FIGS. 1A and 1B through a Wired connection; [0017] FIG. 3 is a schematic diagram of the electrical components of the monitoring devices of FIGS. 1A and 1B; [0018] FIG. 4a is a How chart describing a ?rst algorithm used by the monitoring devices of FIGS. 1A and 1B to calculate calories burned; [0019] FIG. 4b is a How chart describing a second algo rithm used by the monitoring devices of FIGS. 1A and 1B to calculate calories burned; and [0020] FIG. 5 is a How chart describing a second algorithm used by the monitoring devices of FIGS. 1A and 1B to
calculate calories burned.
DETAILED DESCRIPTION OF THE INVENTION
times throughout the day, and then uploads the information
to the Internet-based system 36 using a Wired connection. Alternatively, the monitoring device 5 can measure the
patient 11 continuously during periods of exercise. To vieW patient information sent from the monitoring device 5, the
patient 11 (or other user) accesses the appropriate user
interface hosted on the Website 33 through the Internet 31.
[0026] FIG. 3 shoWs a preferred embodiment of the elec tronic components Within the monitoring device 5. A data processing circuit 61 controls: i) a pulse oximetry circuit 63 connected to an optical pad sensor 6; ii) LCD 4; iii) a
glucometer interface circuit 64 that connects to an external
[0021]
FIGS. 1A and 1B shoW a portable, small-scale
glucometer through a mini USB port 3; iv) an integrated pedometer circuit 9 featuring an accelerometer 59; and v) a short-range Wireless transceiver 7. During operation, the optical pad sensor 6 generates an optical Waveform that the
data-processing circuit 61 processes to measure blood pres
monitoring device 5 that measures information such as
US 2007/0073178 A1
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sure, pulse oximetry, and heart rate as described in more detail below. The sensor 6 combines a photodiode 66, color
TABLE 1-continued
Parameter De?nitions
DEE — TEE — direct energy expenditure (kcal) total energy expenditure (kcal)
?lter 68, and light source/ampli?er 67 on a single silicon
based chip. The light source/ampli?er 67 typically includes light-emitting diodes that generate both red (}\~600 nm) and
infrared (}\~940 nm) radiation. As the heart pumps blood through the patient’s ?nger, blood cells absorb and transmit varying amounts of the red and infrared radiation depending
on hoW much oxygen binds to the cells' hemoglobin. The photodiode 66 detects transmission at both red and infrared Wavelengths, and in response generates a radiation-induced current that travels through the sensor 6 to the pulse
REE — PAEE —
ACC —
resting energy expenditure (kcal/day) physical activity energy expenditure (kJ/kgminute)
accelerometer output (counts/min)
DIT —
FFM — El — BM —
dietary induced thermogenesis (kJ)
fat free mass (kg) energy intake (kJ) body mass (kg)
oximetry circuit 63. The pulse-oximetry circuit 63 connects to an analog-to-digital signal converter 62, Which converts the radiation-induced current into a time-dependent optical Waveform. The analog-to-digital signal converter 62 sends the optical Waveform to the data-processing circuit 61 that processes it to determine blood pressure, pulse-oximetry,
and heart rate, Which are then displayed on the LCD 4. Once
H — Age —
WM — SM — RT —
height (m) age (years) minutes aWake each day (minutes/day)
minutes sleeping each day (minutes/day) recording time (the number of minutes the device is on)
The algorithm 100, Which uses a patient’s physical activity
(PA) level and heart rate (HR), is based on a methodology
information is collected, the monitoring device 5 can send it through a mini USB port 2 to a personal computer 30 as
described With reference to FIG. 2.
[0027] In other embodiments, the monitoring device 5 connects through the mini USB port 3 and glucometer
interface circuit 64 to an external glucometer to doWnload
developed by Moon and Butte (Moon J K and Butte N F; Combined heart rate and activity levels improve estimates of oxygen consumption and carbon dioxide production rates; J appl Physiol 81: 1754-1761, 1996), the contents of Which are incorporated herein by reference.
[0030] As a ?rst step 101, the algorithm 99 features a
process that calibrates the monitoring device so that it can
blood-glucose levels. The monitoring device 5 also pro
cesses information from an integrated pedometer circuit 9 to measure steps and amount of calories burned, as described
accurately measure calories burned during exercise. During
the ?rst step 101 VO2 and HR are simultaneously measured
beloW.
during simulated, representative ‘active’ and ‘inactive’ peri
The monitoring device 5 includes a short-range
ods, de?ned beloW. For example, VO2 can be measured using indirect calorimetry While HR is measured using any number of techniques (e.g., ECG). VO2 is then plotted as a
function of HR for both the active and inactive periods. The resultant data are then ?t With either a quadratic equation
[0028]
Wireless transceiver 7 that sends information through an
antenna 67 to a matched transceiver embedded in an external
device, eg a personal computer. The short-range Wireless
transceiver 7 can also receive information, such as Weight
and body-fat percentage, from an external scale. Abattery 51 poWers all the electrical components Within the small-scale
(for the inactive periods) or a linear equation (for the active periods), shoW beloW, to yield calibration parameters a, b, c,
d. These calibration parameters Will be most accurate if they are measured from a population that is representative to
monitoring device 5, and is preferably a metal hydride battery (generating 3-7V) that can be recharged through a battery-recharge interface 2. The battery-recharge interface
52 can receive poWer through a serial port, eg a computer’s
patients actually using the device.
[0031] inactive
USB port. Buttons control functions Within the monitoring
device such as an on/olf switch 811 and a system reset 8b.
[0032] VO2=a+b*(HR)3
[0033] active
[0029] FIG. 4a shoWs a How chart describing an algorithm 100 used by the monitoring device of FIGS. 1A and 1B to calculate an amount of calories burned during active and inactive periods. Parameters used in this calculation are de?ned in Table 1, beloW.
TABLE 1
Parameter De?nitions
PA — physical activity level measured With accelerometer
[0034] VO2=c+d*(HR)
[0035] Typically the calibration process lasts a feW hours and data describing VO2 and HR are collected every minute. Active and inactive periods for the calibration process
typically include the folloWing:
[0036] inactive
[0037] [0038] 1. 30 minutes of supine rest 2. 15 minutes of standing rest
(counts/minute)
PAI —
M—
physical activity (kJ/kgminute)
PA threshold; median PA measured on treadmill or With
calibration (counts/minute)
PA?ex —
HR —
physical activity flex point; 50% of mean PA
[0039] active
[0040]
[0041]
(counts/minute)
heart rate measured With heart rate monitor
1. 36 minutes of simulated daily activities
a. level Walking at 2 mph for 6 minutes
(beats/minute)
@— HR threshold; mean of highest HR at rest and loWest HR
While Walking (beats/minute)
V02 —
EE —
oxygen consumption (liters/minute)
acute energy expenditure (kcal/minute)
[0042] b. level Walking at 4 mph for 6 minutes
[0043] c. level jogging at 6 mph for 6 minutes
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[0044] d. gardening or lawn care (mowing, raking, shoveling) for 6 minutes
[0047] The branched equations are de?ned in more detail in the following reference, the contents of which are incor
[0045] e. household chores (vacuuming, sweeping and stacking groceries) for 6 minutes
Once calibrated, the algorithm 99 includes a second step 102 that determines threshold values for both PA (de?ned as PA) and HR (de?ned as HR). PA is typically the median value of PA determined while the patient is on the treadmill during the ?rst step 101. HR is typically the mean of highest HR mea sured at rest and the lowest measured HR during
porated herein by reference: Brage S, Brage N, Franks P W, Ekelund U, Wong M, Andersen L B, Froberg K, and Wareham N J; Branched equation modeling of simultaneous accelerometry and heart rate monitoring improves estimate of directly measured physical activity energy expenditure; J appl Physiol 96: 343-351, 2004. The branched equations
process values of HR and PA by comparing them with benchmark values, and in response assign percentages that
de?ne the relative contribution of these parameters to PAEE. These percentages will vary depending on the group used for the calibration process, and ultimately determine the total value for PAEE.
[0048] FIG. 5 shows a ?ow chart illustrating a second algorithm 120 used within the device to calculate the amount of calories a subject burns during both active and inactive periods. The algorithm 120 can use one of three possible
walking. Using the threshold values, the algorithm
99 includes a third step 106 that measures data from
the subject to de?ne periods as being either ‘active’ or ‘inactive’. For example, the subject is determined
to be in an inactive state if PA<PA for one or more
minutes, or alternatively if HR<HR. Alternatively,
the subject is determined to be in an active state if PAZPA for at least one minute and if HR>HR. Using
steps 122, 124, 126 to calculate REE. For example, during
a ?rst step 122 REE is measured directly by ?rst using a
the calibration parameters a, b, c, d determined from
calibration during the ?rst step 101, and the subj ect’s
active or passive state determined during the third
calibration step that determines HR and VO2 during rest; this
method is similar to that used for the ?rst step 101 for the algorithm 100 described with reference to FIG. 4. VO2 can be measured as described in steps 1-4 of the algorithm 100,
step 106, the algorithm then calculates the subject’s oxygen consumed (V02) during a fourth step 108.
Speci?cally, the algorithm records HR during active
or inactive periods, and then using the calibration
and REE is calculated with the following equations:
Kcal/rnin—>VO2*(3.94l+l.106*RQ)
parameters calculates VO2 using either the above mentioned quadratic equation (for an inactive period) or linear equation (for an active period).
During a ?fth step 110 the algorithm 100 converts
[0049] for normal and obese populations
REE=(Kcal/min)* Wit/[+0.95 *(Kcal/min)*SM
[0050] for post-obese populations
REE=(Kcal/min)* WM+O. 85 *(Kcal/min)*SM
VO2 to acute energy expenditure (EE) for both active
and inactive periods using the equation:
EEactive/inactive_4' 8 8 V02, active/inactive
_ *
Using an alternate ?rst step 124 REE is determined using
simple equation that takes into account the patient’s
fat-free mass (FEM):
In this case, FEM is the patient’s mass not attributed to fat, and is typically measured directly or calculated from a
During a sixth step 112 the algorithm converts EE (with units of kcal/minute) to total energy expenditure (TEE) using the total amount of time of either the
active or inactive period. The time is typically mea sured in one-minute increments with a real-time
clock within the monitoring device:
The sixth step 110 yields the amount of calories burned
patient’s body-mass index.
[0051] In another alternative ?rst step 126 estimates REE
using the Harris-Benedict equation:
by the subject.
[0046] FIG. 4b shows an alternate embodiment of the algorithm 99 shown in FIG. 411 used to calculate PAEE. The ?gure shows a ?ow chart illustrating an algorithm 100 that
features a ?rst step 113 where a parameter related to accel
[0052] for men REE=13.75*BM+500.3*H—6.78*Age+66.5 [0053] for women REE=9.56*BM+185*H—4.68*Age+665.1
erometer output called ACC?eXis determined from ACC (in counts/minute). During a second step 114 the algorithm
calibrates VO2 vs. ACC and VO2 vs. HR relationships to determine the calibration coefficients a, b, c, d, e. As with FIG. 4a, these calibration parameters will be most accurate if they are measured from a population that is representative
[0054] In yet another alternate ?rst step 127, REE calcu lated as described above is modi?ed using recording time
(RT), i.e.:
REE’=REE*(1440 —RT) [0055] Once REE is determined, the algorithm 120 uses a second step 128 to estimate DIT using TEE and the equa tion:
to patients actually using the device. During a third step 115, after the calibration parameters are determined, the algo
rithm 100 de?nes branched equation model coe?icients x,
Y1, Y2, Z1, Z2, Pl_4 based on minimizing standard error of PAI estimate. During a fourth step 116 the algorithm calcu lates PAI using a series of branched equations 117, 118,
using the coefficients from the third step 115. This leads to a ?fth step 118 wherein the algorithm converts PAI (with units of kJ/kg/min) to PAEE (kcal/min).
[0056] Alternatively, DIT is calculated by estimating the
macronutrient composition of the subject’s diet. This is done using the following equation for the second step 130 of the
algorithm 120:
DIT=0.025 *fatEZ
teinEZ
—0.07*carbohydrateEZ+O.275*pro—
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During a third step 132 the algorithm uses TEE (described above With reference to FIG. 4a) or PAEE (described above With reference to FIG. 4b). For example, in one part of the third step 133, TEE is determined as described above, and then combined With the ?rst and second steps to determine DEE 14211. In an alternate step 134, PAEE is determined
a transmitting component for transmitting the heart rate, exercise, calorie, and Weight information to an external
device. 2. The monitoring device of claim 1, Wherein the micro processor is con?gured to operate a computer algorithm that
processes the heart rate and exercise information to generate calorie information.
using calibration information that describes the relationship
betWeen both PA and HR and VO2 as described above. Once
REE (step 1), DIT (step 2), PAEE (step 3) or TEE (step 3)
are determined, the algorithm 120 uses a fourth step 14211,!) to determine DEE:
DEE =REE+DIT+PAEE
or
3. The monitoring device of claim 2, Wherein the algo rithm is further con?gured to process the physical activity
information to determine Whether a subject is at rest or
undergoing exercise.
4. The monitoring device of claim 3, Wherein the algo
rithm is further con?gured to compare the heart rate infor mation to pre-determined calibration information to deter mine an amount of calories burned by the subject.
DEE =REE+DIT+ TEE
[0057] Methods for processing optical and electrical
Waveforms to determine blood pressure Without using a culf
5. The monitoring device of claim 4, Wherein the cali
bration information comprises a data table that correlates
oxygen consumed as a function of heart rate.
are described in the folloWing co-pending patent applica
tions, the entire contents of Which are incorporated by reference: 1) CUFFLESS BLOOD-PRESSURE MONI TORING DEVICE AND ACCOMPANYING WIRELESS, INTERNET-BASED SYSTEM (U.S. Ser. No 10/709,015;
6. The monitoring device of claim 5, Wherein the algo rithm is further con?gured to calculate caloric expenditure
from an amount of oxygen consumed.
?led Apr. 7, 2004); 2) CUFFLESS SYSTEM FOR MEA SURING BLOOD PRESSURE (U.S. Ser. No. 10/709,014; ?led Apr. 7, 2004); 3) CUFFLESS BLOOD PRESSURE
MONITORING DEVICE AND ACCOMPANYING WEB
7. The monitoring device of claim 1, Wherein the motion
sensing device is an accelerometer.
8. The monitoring device according to claim 1, Wherein
the transmitting component is a serial connection.
SERVICES INTERFACE (U.S. Ser. No. 10/810,237; ?led Mar. 26, 2004); 4) VITAL-SIGN MONITORING DEVICE FOR ATHLETIC APPLICATIONS (U.S. Ser. No.; ?led Sep. 13, 2004); 5) CUFFLESS BLOOD PRESSURE MONI
TORING DEVICE AND ACCOMPANYING WIRELESS
9. The monitoring device according to claim 8, Wherein
the serial connection is a USB connection.
10. The monitoring device according to claim 1, Wherein
the transmitting component is a Wireless transceiver that operates a Wireless protocol.
MOBILE DEVICE (U.S. Ser. No. 10/967,511; ?led Oct. 18, 2004); and 6) BLOOD PRESSURE MONITORING DEVI
CEING DEVICE FEATURING A CALIBRATION-BASED
ANALYSIS (U.S. Ser. No. 10/967,610; ?led Oct. 18, 2004);
7) PERSONAL COMPUTER-BASED VITAL SIGN MONITORING DEVICE (U.S. Ser. No. 10/906,342; ?led Feb. 15, 2005); and 8) PATCH SENSOR FOR MEASUR
ING BLOOD PRESSURE WITHOUT A CUFF (U .S. Ser.
11. The monitoring device according to claim 10, Wherein the Wireless protocol is based on BluetoothTM, 802.11a, 802.11b, 802.1g, or 802.154. 12. The monitoring device according to claim 1, Wherein
the Weight information is Weight and percentage body fat. 13. The monitoring device according to claim 1, Wherein
the external device that receives the heart rate, exercise, calorie, and Weight information is a personal computer. 14. The monitoring device according to claim 1, Wherein the personal computer comprises a softWare component that
No. 10/906,315; ?led Feb. 14, 2005).
[0058] Still other embodiments are Within the scope of the
folloWing claims.
I claim as my invention:
collects the heart rate, exercise, calorie, and Weight infor
mation and transmits this information to an Internet-acces
sible Website.
1. A monitoring device comprising:
a cardiac sensor component comprising at least one
15. A monitoring device comprising:
a cardiac sensor component comprising at least one
light-emitting diode and a photodetector;
a pedometer component comprising at least one motion
light-emitting diode and a photodetector;
a pedometer component comprising at least one motion
sensing component;
a Wireless component comprising a Wireless interface
sensing component;
a Wireless component comprising a Wireless interface
con?gured to communicate With an external Weight
con?gured to communicate With an external Weight
scale;
a microprocessor in electrical communication With the
scale;
a microprocessor in electrical communication With the
cardiac sensor, pedometer, and Wireless components and con?gured to analyze: i) a signal from the cardiac sensor component to generate heart rate information; ii) a signal from the pedometer component to generate exercise information; iii) heart rate and exercise infor mation to generate calorie information; and iv) a signal from the external Weight scale to calculate Weight
cardiac sensor, pedometer, and Wireless components and con?gured to operate a computer program that:
1) analyZes: i) a signal from the cardiac sensor com ponent to generate heart rate information; ii) a signal from the pedometer component to generate exercise information; and iii) a signal from the external
information; and
Weight scale to calculate Weight information; and 2)
US 2007/0073178 A1
Mar. 29, 2007
analyzes: i) exercise information to determine
Whether a subject is at rest or undergoing exercise; and ii) heart rate information in combination With a pre-determined calibration information to determine an amount of calories burned by the subject; and
a Wireless component comprising a Wireless interface
con?gured to communicate With an external Weight
scale;
a microprocessor in electrical communication With the
a transmitting component for transmitting the heart rate, exercise, calorie, and Weight information to an external
device.
16. The monitoring device according to claim 15, Wherein the external device that receives the heart rate, exercise, calorie, and Weight information is a personal computer. 17. The monitoring device according to claim 16, Wherein the personal computer comprises a softWare component that collects the heart rate, exercise, calorie, and Weight infor
mation and transmits this information to an Internet-acces
cardiac sensor, pedometer, and Wireless components and con?gured to operate a computer program that: l) analyZes: i) a signal from the cardiac sensor component to generate heart rate information; ii) a signal from the pedometer component to generate exercise information; and iii) a signal from the external Weight scale to calculate Weight informa
tion; and 2) analyZes: i) exercise information to
determine Whether a subject is at rest or undergo
ing exercise; and ii) heart rate information in
combination With a pre-determined calibration
information to determine an amount of calories
sible Website.
18. A system comprising:
a monitoring device comprising:
a cardiac sensor component comprising at least one
burned by the subject; and
a transmitting component for transmitting the heart
rate, exercise, calorie, and Weight information; and
an lntemet-accessible Website con?gured to receive the
light-emitting diode and a photodetector;
a pedometer component comprising at least one
heart rate, exercise, calorie, and Weight information.
* * * * *
motion-sensing component;
(19) United States (12) Patent Application Publication (10) Pub. No.: US 2007/0073178 A1
Browning et al.
(54) MONITORING DEVICE FOR MEASURING
CALORIE EXPENDITURE
(43) Pub. Date:
Mar. 29, 2007
Publication Classi?cation
(51)
(75) Inventors: Ray Browning, Denver, CO (US); Christopher Hall, San Francisco, CA
(US); Matthew Banet, Del Mar, CA
Int. Cl. A61B 5/04
Us. or.
(2006.01)
(52)
............................................................ .. 600/519
(Us)
Correspondence Address:
MCDONNELL BOEHNEN HULBERT & BERGHOFF LLP 300 S. WACKER DRIVE 32ND FLOOR
(57)
ABSTRACT
The invention provides a monitoring device that features: 1)
a cardiac sensor component With at least one light-emitting
diode and a photodetector; 2) a pedometer component With
at least one motion-sensing component (e.g., an accelerom eter); and 3) a Wireless component With a Wireless interface that communicates With an external Weight scale. The device also features a microprocessor in electrical communication With the cardiac sensor, pedometer, and Wireless compo
CHICAGO, IL 60606 (US)
(73) Assignee: Berkeley HeartLab, Inc.
(21) Appl. No.:
(22) Filed:
11/522,565
Sep. 18, 2006
nents and con?gured to analyze: l) a signal from the cardiac
sensor component to generate heart rate information; 2) a
signal from the pedometer component to generate exercise
information; 3) heart rate and exercise information to gen erate calorie information; and 4) a signal from the external
Related US. Application Data
(60) Provisional application No. 60/72l,665, ?led on Sep. 29, 2005.
Weight scale to calculate Weight information (e.g., Weight
and percent body fat).
Patent Application Publication Mar. 29, 2007 Sheet 1 0f 6
US 2007/0073178 A1
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Mar. 29, 2007
MONITORING DEVICE FOR MEASURING CALORIE EXPENDITURE CROSS REFERENCES TO RELATED APPLICATION
from the cardiac sensor component to generate heart rate
information; 2) a signal from the pedometer component to generate exercise information; 3) heart rate and exercise information to generate calorie information; and 4) a signal from the external Weight scale to calculate Weight informa
[0001] This application claims the bene?t of US. Provi sional Application Ser. No. 60/721,665 ?led on Sep. 29,
tion (e.g., Weight and percent body fat). The monitoring
device also includes a transmitting component (eg a serial port or Wireless interface) that transmits the heart rate, exercise, calorie, and Weight information to an external device, such as a personal computer connected to the Inter
net.
2005 and is hereby incorporated by reference.
BACKGROUND OF THE INVENTION
[0002]
1. Field of the Invention
[0008] In embodiments, the microprocessor is con?gured
to operate a computer algorithm that processes the heart rate and exercise information to generate calorie information, such as calories burned. For example, the algorithm can
[0003] The present invention relates to medical devices for monitoring information, such as heart rate and calories burned, from a subject.
[0004] 2. Description of the Related Art
[0005] Pedometers are common devices that typically
include a motion-sensitive component, such as an acceler
process the physical activity information to determine
Whether a subject is at rest or undergoing exercise, and once this is determined compare the heart rate information to pre-determined calibration information to determine an
ometer or a tilt sWitch, that typically generates an analog
amount of calories burned by the subject. More speci?cally,
the calibration information can include a predetermined data table or mathematical function that correlates oxygen con sumed as a function of heart rate. The algorithm can then
voltage that peaks in response to motion (e.g., steps). A microcontroller can receive the analog voltage, digitiZe it,
and then process it by counting the peaks to determine a
subject’s steps. Heart rate monitors are also common
devices that measure a subject’s heart rate, typically by
calculate caloric expenditure from the amount of oxygen consumed.
measuring a biometric signal (i.e., by processing an electri
cal signal collected by an electrode, such as that used in an
[0009] The invention has many advantages, particularly in
providing a small-scale, loW-cost device that rapidly mea
sures health-related indicators such as blood pressure, heart
ECG) or an optical plethysmograph (i.e., by processing an
optical signal collected by a pulse oximeter).
[0006] Pulse oximeters are typically Worn on a patient’s ?nger or ear lobe, and feature a processing module that
rate, and blood oxygen content. In embodiments, the device makes blood pressure measurements Without using a culf in
a matter of seconds, meaning patients can easily monitoring
device this property With minimal discomfort. In this Way the monitoring device combines all the bene?ts of conven
analyZes data generated by an optical module. The optical
module typically includes ?rst and second light sources
(e.g., light-emitting diodes, or LEDs) that transmit optical radiation at, respectively, red (7»~630-670 nm) and infrared (7»~800-l200nm) Wavelengths. The optical module also fea
tures a photodetector that detects radiation transmitted or
tional blood-pressure measuring devices Without any of the
obvious draWbacks (e.g., restrictive, uncomfortable culfs).
Its measurement, made With an optical ‘pad sensor’, is basically unobtrusive to the patient, and thus alleviates conditions, such as a poorly ?tting culf, that can erroneously affect a blood-pressure measurement. Ultimately this alloWs patients to measure their vital signs throughout the day (e. g., While at Work), thereby generating a complete set of infor mation, rather than just a single, isolated measurement.
Physicians can use this information to diagnose a Wide
re?ected by an underlying artery. Typically the red and infrared LEDs sequentially emit radiation that is partially absorbed by blood ?oWing in the artery. The photodetector
is synchroniZed With the LEDs to detect transmitted or
re?ected radiation. In response, the photodetector generates a separate radiation-induced signal for each Wavelength. The signal, called a plethysmograph, is an optical Waveform that
varies in a time-dependent manner as each heartbeat varies
variety of conditions, particularly hypertension and its many
related diseases.
the volume of arterial blood, and hence the amount of transmitted or re?ected radiation. A microprocessor in the
[0010]
The device additionally includes a simple Wired or
pulse oximeter processes the relative absorption of red and
infrared radiation to determine the oxygen saturation in the
patient’s blood. Anumber betWeen 94%-l00% is considered normal, While a value beloW 85% typically indicates the
Wireless interface that sends vital-sign information to a personal computer. For example, the device can include a Universal Serial Bus (USB) connector that connects to the
computer’s back panel. Once a measurement is made, the
device stores it on an on-board memory and then sends the
patient requires hospitaliZation.
SUMMARY OF THE INVENTION
[0007]
In one aspect the invention provides a monitoring
device that features: 1) a cardiac sensor component With at least one LED and a photodetector; 2) a pedometer compo nent With at least one motion-sensing component (e.g., an accelerometer); and 3) a Wireless component With a Wireless interface that communicates With an external Weight scale. The device also features a microprocessor in electrical
information through the USB port to a softWare program running on the computer. Alternatively, the device can include a short-range radio interface (based on, e.g., Blue toothTM or 802.154) that Wirelessly sends the information to a matched short-range radio Within the computer. The soft Ware program running on the computer then analyZes the information to generate statistics on a patient’s vital signs
(e.g., average values, standard deviation, beat-to-beat varia
tions) that are not available With conventional devices that make only isolated measurements. The computer can then send the information through a Wired or Wireless connection to a central computer system connected to the Internet.
communication With the cardiac sensor, pedometer, and
Wireless components and con?gured to analyZe: l) a signal
US 2007/0073178 A1
Mar. 29, 2007
[0011]
The central computer system can further analyze
blood pressure, pulse oximetry, heart rate, glucose levels,
calories burned and steps traveled from a patient 1. The
the information, eg display it on an Internet-accessible Website. This means medical professionals can characterize
a patient’s real-time vital signs during their day-to-day
activities, rather than rely on an isolated measurement
monitoring device 5, typically Worn on the patient’s belt 13, features: i) an integrated, optical ‘pad sensor’6 that culf lessly measures blood pressure, pulse oximetry, and heart
rate from a patient’s ?nger as described in more detail
during a medical check-up. The Website typically features
one or more Web pages that display the blood test, vital sign,
beloW; and ii) an integrated pedometer circuit 9 that mea
sures steps and, using one or more algorithms, calories
exercise, and personal information. In embodiments, the
Website includes a ?rst Web interface that displays informa tion for a single patient, and a second Web interface that displays information for a group of patients. For example, a
medical professional (eg a physician, nurse, nurse practi tioner, dietician, or clinical educator) associated With a group of patients could use the second Web interface to drive compliance for a disease-management program. Both Web
burned. To receive information from external devices, the monitoring device 5 also includes: i) a serial connector 3 that connects and doWnloads information from an external glu cometer 22; and ii) a short-range Wireless transceiver 7 that receives information such as body Weight and percentage of body fat from an external scale 21. The patient vieWs
information from a liquid crystal display (LCD) display 4
mounted on the monitoring device 5, and can interact With the monitoring device 5 (e.g., reset or reprogram it) using a
interfaces typically include multiple Web pages that, in turn,
feature both static and dynamic content, described in detail beloW.
[0012] The Website can also include a messaging engine that processes real-time information collected from the device to, among other things, help a patient comply With a
disease-management program, such as a personaliZed car
series of buttons 8a, 8b.
[0022] The monitoring device can be used for a variety of
applications relating to, e.g., disease management, health maintenance, and medical diagnosis.
[0023] FIG. 2 shoWs a preferred embodiment of an Inter net-based system 36 that operates in concert With the small scale monitoring device 5 to send information from the
patient 11 to an Internet-accessible Website 33. There, a user can access the information using a conventional Web
diovascular risk reduction program. The messaging engine
analyses blood test, vital sign, exercise, and personal infor
mation, taken alone or combined, to generate personaliZed, patient-speci?c messages. Ultimately the Internet-based sys
tem, monitoring device, and messaging engine combine to
form an interconnected, easy-to-use tool that can engage the
broWser through a patient interface 15 or a physician inter
patient in a disease-management program, encourage fol
loW-on medical appointments, and build patient compliance.
These factors, in turn, can help the patient loWer their risk
for certain medical conditions.
face 34. Typically the patient interface 15 shoWs information from a single user, Whereas the physician interface 34 displays information for multiple patients. In both cases, information ?oWs from the monitoring device 5 through a
USB cable 10 to an external device, e.g., a personal com
[0013] These and other advantages of the invention Will be apparent from the folloWing detailed description and from
the claims.
BRIEF DESCRIPTION OF THE DRAWINGS [0014] FIG. 1A is a semi-schematic vieW of a portable, small-scale monitoring device that measures blood pressure,
puter 30. The personal computer 30 connects to the Internet 31 through a Wired gateWay softWare system 32, such as an Internet Service Provider.
[0024] In other embodiments, the small-scale monitoring device 5 transmits patient information using a short-range
Wireless transceiver 7 through a short-range Wireless con
pulse oximetry, heart rate, glucose levels, Weight, steps
traveled, and calories burned;
[0015] FIG. 1B is a semi-schematic vieW of the monitor ing device of FIG. 1A Worn on a patient’s belt;
[0016] FIG. 2 is a schematic vieW of an Internet-based
nection 37 (e.g., BluetoothTM, 80215.4, part-l5) to the personal computer 30. For example, the small-scale moni
toring device 5 can transmit to a matched transceiver 12
Within (or connected to) the personal computer 30.
[0025] During typical operation, the patient 11 uses the
monitoring device 5 for a period of time ranging from a l-3 months. Typically the patient 11 takes measurements a feW
system that receives information from the monitoring device of FIGS. 1A and 1B through a Wired connection; [0017] FIG. 3 is a schematic diagram of the electrical components of the monitoring devices of FIGS. 1A and 1B; [0018] FIG. 4a is a How chart describing a ?rst algorithm used by the monitoring devices of FIGS. 1A and 1B to calculate calories burned; [0019] FIG. 4b is a How chart describing a second algo rithm used by the monitoring devices of FIGS. 1A and 1B to calculate calories burned; and [0020] FIG. 5 is a How chart describing a second algorithm used by the monitoring devices of FIGS. 1A and 1B to
calculate calories burned.
DETAILED DESCRIPTION OF THE INVENTION
times throughout the day, and then uploads the information
to the Internet-based system 36 using a Wired connection. Alternatively, the monitoring device 5 can measure the
patient 11 continuously during periods of exercise. To vieW patient information sent from the monitoring device 5, the
patient 11 (or other user) accesses the appropriate user
interface hosted on the Website 33 through the Internet 31.
[0026] FIG. 3 shoWs a preferred embodiment of the elec tronic components Within the monitoring device 5. A data processing circuit 61 controls: i) a pulse oximetry circuit 63 connected to an optical pad sensor 6; ii) LCD 4; iii) a
glucometer interface circuit 64 that connects to an external
[0021]
FIGS. 1A and 1B shoW a portable, small-scale
glucometer through a mini USB port 3; iv) an integrated pedometer circuit 9 featuring an accelerometer 59; and v) a short-range Wireless transceiver 7. During operation, the optical pad sensor 6 generates an optical Waveform that the
data-processing circuit 61 processes to measure blood pres
monitoring device 5 that measures information such as
US 2007/0073178 A1
Mar. 29, 2007
sure, pulse oximetry, and heart rate as described in more detail below. The sensor 6 combines a photodiode 66, color
TABLE 1-continued
Parameter De?nitions
DEE — TEE — direct energy expenditure (kcal) total energy expenditure (kcal)
?lter 68, and light source/ampli?er 67 on a single silicon
based chip. The light source/ampli?er 67 typically includes light-emitting diodes that generate both red (}\~600 nm) and
infrared (}\~940 nm) radiation. As the heart pumps blood through the patient’s ?nger, blood cells absorb and transmit varying amounts of the red and infrared radiation depending
on hoW much oxygen binds to the cells' hemoglobin. The photodiode 66 detects transmission at both red and infrared Wavelengths, and in response generates a radiation-induced current that travels through the sensor 6 to the pulse
REE — PAEE —
ACC —
resting energy expenditure (kcal/day) physical activity energy expenditure (kJ/kgminute)
accelerometer output (counts/min)
DIT —
FFM — El — BM —
dietary induced thermogenesis (kJ)
fat free mass (kg) energy intake (kJ) body mass (kg)
oximetry circuit 63. The pulse-oximetry circuit 63 connects to an analog-to-digital signal converter 62, Which converts the radiation-induced current into a time-dependent optical Waveform. The analog-to-digital signal converter 62 sends the optical Waveform to the data-processing circuit 61 that processes it to determine blood pressure, pulse-oximetry,
and heart rate, Which are then displayed on the LCD 4. Once
H — Age —
WM — SM — RT —
height (m) age (years) minutes aWake each day (minutes/day)
minutes sleeping each day (minutes/day) recording time (the number of minutes the device is on)
The algorithm 100, Which uses a patient’s physical activity
(PA) level and heart rate (HR), is based on a methodology
information is collected, the monitoring device 5 can send it through a mini USB port 2 to a personal computer 30 as
described With reference to FIG. 2.
[0027] In other embodiments, the monitoring device 5 connects through the mini USB port 3 and glucometer
interface circuit 64 to an external glucometer to doWnload
developed by Moon and Butte (Moon J K and Butte N F; Combined heart rate and activity levels improve estimates of oxygen consumption and carbon dioxide production rates; J appl Physiol 81: 1754-1761, 1996), the contents of Which are incorporated herein by reference.
[0030] As a ?rst step 101, the algorithm 99 features a
process that calibrates the monitoring device so that it can
blood-glucose levels. The monitoring device 5 also pro
cesses information from an integrated pedometer circuit 9 to measure steps and amount of calories burned, as described
accurately measure calories burned during exercise. During
the ?rst step 101 VO2 and HR are simultaneously measured
beloW.
during simulated, representative ‘active’ and ‘inactive’ peri
The monitoring device 5 includes a short-range
ods, de?ned beloW. For example, VO2 can be measured using indirect calorimetry While HR is measured using any number of techniques (e.g., ECG). VO2 is then plotted as a
function of HR for both the active and inactive periods. The resultant data are then ?t With either a quadratic equation
[0028]
Wireless transceiver 7 that sends information through an
antenna 67 to a matched transceiver embedded in an external
device, eg a personal computer. The short-range Wireless
transceiver 7 can also receive information, such as Weight
and body-fat percentage, from an external scale. Abattery 51 poWers all the electrical components Within the small-scale
(for the inactive periods) or a linear equation (for the active periods), shoW beloW, to yield calibration parameters a, b, c,
d. These calibration parameters Will be most accurate if they are measured from a population that is representative to
monitoring device 5, and is preferably a metal hydride battery (generating 3-7V) that can be recharged through a battery-recharge interface 2. The battery-recharge interface
52 can receive poWer through a serial port, eg a computer’s
patients actually using the device.
[0031] inactive
USB port. Buttons control functions Within the monitoring
device such as an on/olf switch 811 and a system reset 8b.
[0032] VO2=a+b*(HR)3
[0033] active
[0029] FIG. 4a shoWs a How chart describing an algorithm 100 used by the monitoring device of FIGS. 1A and 1B to calculate an amount of calories burned during active and inactive periods. Parameters used in this calculation are de?ned in Table 1, beloW.
TABLE 1
Parameter De?nitions
PA — physical activity level measured With accelerometer
[0034] VO2=c+d*(HR)
[0035] Typically the calibration process lasts a feW hours and data describing VO2 and HR are collected every minute. Active and inactive periods for the calibration process
typically include the folloWing:
[0036] inactive
[0037] [0038] 1. 30 minutes of supine rest 2. 15 minutes of standing rest
(counts/minute)
PAI —
M—
physical activity (kJ/kgminute)
PA threshold; median PA measured on treadmill or With
calibration (counts/minute)
PA?ex —
HR —
physical activity flex point; 50% of mean PA
[0039] active
[0040]
[0041]
(counts/minute)
heart rate measured With heart rate monitor
1. 36 minutes of simulated daily activities
a. level Walking at 2 mph for 6 minutes
(beats/minute)
@— HR threshold; mean of highest HR at rest and loWest HR
While Walking (beats/minute)
V02 —
EE —
oxygen consumption (liters/minute)
acute energy expenditure (kcal/minute)
[0042] b. level Walking at 4 mph for 6 minutes
[0043] c. level jogging at 6 mph for 6 minutes
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[0044] d. gardening or lawn care (mowing, raking, shoveling) for 6 minutes
[0047] The branched equations are de?ned in more detail in the following reference, the contents of which are incor
[0045] e. household chores (vacuuming, sweeping and stacking groceries) for 6 minutes
Once calibrated, the algorithm 99 includes a second step 102 that determines threshold values for both PA (de?ned as PA) and HR (de?ned as HR). PA is typically the median value of PA determined while the patient is on the treadmill during the ?rst step 101. HR is typically the mean of highest HR mea sured at rest and the lowest measured HR during
porated herein by reference: Brage S, Brage N, Franks P W, Ekelund U, Wong M, Andersen L B, Froberg K, and Wareham N J; Branched equation modeling of simultaneous accelerometry and heart rate monitoring improves estimate of directly measured physical activity energy expenditure; J appl Physiol 96: 343-351, 2004. The branched equations
process values of HR and PA by comparing them with benchmark values, and in response assign percentages that
de?ne the relative contribution of these parameters to PAEE. These percentages will vary depending on the group used for the calibration process, and ultimately determine the total value for PAEE.
[0048] FIG. 5 shows a ?ow chart illustrating a second algorithm 120 used within the device to calculate the amount of calories a subject burns during both active and inactive periods. The algorithm 120 can use one of three possible
walking. Using the threshold values, the algorithm
99 includes a third step 106 that measures data from
the subject to de?ne periods as being either ‘active’ or ‘inactive’. For example, the subject is determined
to be in an inactive state if PA<PA for one or more
minutes, or alternatively if HR<HR. Alternatively,
the subject is determined to be in an active state if PAZPA for at least one minute and if HR>HR. Using
steps 122, 124, 126 to calculate REE. For example, during
a ?rst step 122 REE is measured directly by ?rst using a
the calibration parameters a, b, c, d determined from
calibration during the ?rst step 101, and the subj ect’s
active or passive state determined during the third
calibration step that determines HR and VO2 during rest; this
method is similar to that used for the ?rst step 101 for the algorithm 100 described with reference to FIG. 4. VO2 can be measured as described in steps 1-4 of the algorithm 100,
step 106, the algorithm then calculates the subject’s oxygen consumed (V02) during a fourth step 108.
Speci?cally, the algorithm records HR during active
or inactive periods, and then using the calibration
and REE is calculated with the following equations:
Kcal/rnin—>VO2*(3.94l+l.106*RQ)
parameters calculates VO2 using either the above mentioned quadratic equation (for an inactive period) or linear equation (for an active period).
During a ?fth step 110 the algorithm 100 converts
[0049] for normal and obese populations
REE=(Kcal/min)* Wit/[+0.95 *(Kcal/min)*SM
[0050] for post-obese populations
REE=(Kcal/min)* WM+O. 85 *(Kcal/min)*SM
VO2 to acute energy expenditure (EE) for both active
and inactive periods using the equation:
EEactive/inactive_4' 8 8 V02, active/inactive
_ *
Using an alternate ?rst step 124 REE is determined using
simple equation that takes into account the patient’s
fat-free mass (FEM):
In this case, FEM is the patient’s mass not attributed to fat, and is typically measured directly or calculated from a
During a sixth step 112 the algorithm converts EE (with units of kcal/minute) to total energy expenditure (TEE) using the total amount of time of either the
active or inactive period. The time is typically mea sured in one-minute increments with a real-time
clock within the monitoring device:
The sixth step 110 yields the amount of calories burned
patient’s body-mass index.
[0051] In another alternative ?rst step 126 estimates REE
using the Harris-Benedict equation:
by the subject.
[0046] FIG. 4b shows an alternate embodiment of the algorithm 99 shown in FIG. 411 used to calculate PAEE. The ?gure shows a ?ow chart illustrating an algorithm 100 that
features a ?rst step 113 where a parameter related to accel
[0052] for men REE=13.75*BM+500.3*H—6.78*Age+66.5 [0053] for women REE=9.56*BM+185*H—4.68*Age+665.1
erometer output called ACC?eXis determined from ACC (in counts/minute). During a second step 114 the algorithm
calibrates VO2 vs. ACC and VO2 vs. HR relationships to determine the calibration coefficients a, b, c, d, e. As with FIG. 4a, these calibration parameters will be most accurate if they are measured from a population that is representative
[0054] In yet another alternate ?rst step 127, REE calcu lated as described above is modi?ed using recording time
(RT), i.e.:
REE’=REE*(1440 —RT) [0055] Once REE is determined, the algorithm 120 uses a second step 128 to estimate DIT using TEE and the equa tion:
to patients actually using the device. During a third step 115, after the calibration parameters are determined, the algo
rithm 100 de?nes branched equation model coe?icients x,
Y1, Y2, Z1, Z2, Pl_4 based on minimizing standard error of PAI estimate. During a fourth step 116 the algorithm calcu lates PAI using a series of branched equations 117, 118,
using the coefficients from the third step 115. This leads to a ?fth step 118 wherein the algorithm converts PAI (with units of kJ/kg/min) to PAEE (kcal/min).
[0056] Alternatively, DIT is calculated by estimating the
macronutrient composition of the subject’s diet. This is done using the following equation for the second step 130 of the
algorithm 120:
DIT=0.025 *fatEZ
teinEZ
—0.07*carbohydrateEZ+O.275*pro—
US 2007/0073178 A1
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During a third step 132 the algorithm uses TEE (described above With reference to FIG. 4a) or PAEE (described above With reference to FIG. 4b). For example, in one part of the third step 133, TEE is determined as described above, and then combined With the ?rst and second steps to determine DEE 14211. In an alternate step 134, PAEE is determined
a transmitting component for transmitting the heart rate, exercise, calorie, and Weight information to an external
device. 2. The monitoring device of claim 1, Wherein the micro processor is con?gured to operate a computer algorithm that
processes the heart rate and exercise information to generate calorie information.
using calibration information that describes the relationship
betWeen both PA and HR and VO2 as described above. Once
REE (step 1), DIT (step 2), PAEE (step 3) or TEE (step 3)
are determined, the algorithm 120 uses a fourth step 14211,!) to determine DEE:
DEE =REE+DIT+PAEE
or
3. The monitoring device of claim 2, Wherein the algo rithm is further con?gured to process the physical activity
information to determine Whether a subject is at rest or
undergoing exercise.
4. The monitoring device of claim 3, Wherein the algo
rithm is further con?gured to compare the heart rate infor mation to pre-determined calibration information to deter mine an amount of calories burned by the subject.
DEE =REE+DIT+ TEE
[0057] Methods for processing optical and electrical
Waveforms to determine blood pressure Without using a culf
5. The monitoring device of claim 4, Wherein the cali
bration information comprises a data table that correlates
oxygen consumed as a function of heart rate.
are described in the folloWing co-pending patent applica
tions, the entire contents of Which are incorporated by reference: 1) CUFFLESS BLOOD-PRESSURE MONI TORING DEVICE AND ACCOMPANYING WIRELESS, INTERNET-BASED SYSTEM (U.S. Ser. No 10/709,015;
6. The monitoring device of claim 5, Wherein the algo rithm is further con?gured to calculate caloric expenditure
from an amount of oxygen consumed.
?led Apr. 7, 2004); 2) CUFFLESS SYSTEM FOR MEA SURING BLOOD PRESSURE (U.S. Ser. No. 10/709,014; ?led Apr. 7, 2004); 3) CUFFLESS BLOOD PRESSURE
MONITORING DEVICE AND ACCOMPANYING WEB
7. The monitoring device of claim 1, Wherein the motion
sensing device is an accelerometer.
8. The monitoring device according to claim 1, Wherein
the transmitting component is a serial connection.
SERVICES INTERFACE (U.S. Ser. No. 10/810,237; ?led Mar. 26, 2004); 4) VITAL-SIGN MONITORING DEVICE FOR ATHLETIC APPLICATIONS (U.S. Ser. No.; ?led Sep. 13, 2004); 5) CUFFLESS BLOOD PRESSURE MONI
TORING DEVICE AND ACCOMPANYING WIRELESS
9. The monitoring device according to claim 8, Wherein
the serial connection is a USB connection.
10. The monitoring device according to claim 1, Wherein
the transmitting component is a Wireless transceiver that operates a Wireless protocol.
MOBILE DEVICE (U.S. Ser. No. 10/967,511; ?led Oct. 18, 2004); and 6) BLOOD PRESSURE MONITORING DEVI
CEING DEVICE FEATURING A CALIBRATION-BASED
ANALYSIS (U.S. Ser. No. 10/967,610; ?led Oct. 18, 2004);
7) PERSONAL COMPUTER-BASED VITAL SIGN MONITORING DEVICE (U.S. Ser. No. 10/906,342; ?led Feb. 15, 2005); and 8) PATCH SENSOR FOR MEASUR
ING BLOOD PRESSURE WITHOUT A CUFF (U .S. Ser.
11. The monitoring device according to claim 10, Wherein the Wireless protocol is based on BluetoothTM, 802.11a, 802.11b, 802.1g, or 802.154. 12. The monitoring device according to claim 1, Wherein
the Weight information is Weight and percentage body fat. 13. The monitoring device according to claim 1, Wherein
the external device that receives the heart rate, exercise, calorie, and Weight information is a personal computer. 14. The monitoring device according to claim 1, Wherein the personal computer comprises a softWare component that
No. 10/906,315; ?led Feb. 14, 2005).
[0058] Still other embodiments are Within the scope of the
folloWing claims.
I claim as my invention:
collects the heart rate, exercise, calorie, and Weight infor
mation and transmits this information to an Internet-acces
sible Website.
1. A monitoring device comprising:
a cardiac sensor component comprising at least one
15. A monitoring device comprising:
a cardiac sensor component comprising at least one
light-emitting diode and a photodetector;
a pedometer component comprising at least one motion
light-emitting diode and a photodetector;
a pedometer component comprising at least one motion
sensing component;
a Wireless component comprising a Wireless interface
sensing component;
a Wireless component comprising a Wireless interface
con?gured to communicate With an external Weight
con?gured to communicate With an external Weight
scale;
a microprocessor in electrical communication With the
scale;
a microprocessor in electrical communication With the
cardiac sensor, pedometer, and Wireless components and con?gured to analyze: i) a signal from the cardiac sensor component to generate heart rate information; ii) a signal from the pedometer component to generate exercise information; iii) heart rate and exercise infor mation to generate calorie information; and iv) a signal from the external Weight scale to calculate Weight
cardiac sensor, pedometer, and Wireless components and con?gured to operate a computer program that:
1) analyZes: i) a signal from the cardiac sensor com ponent to generate heart rate information; ii) a signal from the pedometer component to generate exercise information; and iii) a signal from the external
information; and
Weight scale to calculate Weight information; and 2)
US 2007/0073178 A1
Mar. 29, 2007
analyzes: i) exercise information to determine
Whether a subject is at rest or undergoing exercise; and ii) heart rate information in combination With a pre-determined calibration information to determine an amount of calories burned by the subject; and
a Wireless component comprising a Wireless interface
con?gured to communicate With an external Weight
scale;
a microprocessor in electrical communication With the
a transmitting component for transmitting the heart rate, exercise, calorie, and Weight information to an external
device.
16. The monitoring device according to claim 15, Wherein the external device that receives the heart rate, exercise, calorie, and Weight information is a personal computer. 17. The monitoring device according to claim 16, Wherein the personal computer comprises a softWare component that collects the heart rate, exercise, calorie, and Weight infor
mation and transmits this information to an Internet-acces
cardiac sensor, pedometer, and Wireless components and con?gured to operate a computer program that: l) analyZes: i) a signal from the cardiac sensor component to generate heart rate information; ii) a signal from the pedometer component to generate exercise information; and iii) a signal from the external Weight scale to calculate Weight informa
tion; and 2) analyZes: i) exercise information to
determine Whether a subject is at rest or undergo
ing exercise; and ii) heart rate information in
combination With a pre-determined calibration
information to determine an amount of calories
sible Website.
18. A system comprising:
a monitoring device comprising:
a cardiac sensor component comprising at least one
burned by the subject; and
a transmitting component for transmitting the heart
rate, exercise, calorie, and Weight information; and
an lntemet-accessible Website con?gured to receive the
light-emitting diode and a photodetector;
a pedometer component comprising at least one
heart rate, exercise, calorie, and Weight information.
* * * * *
motion-sensing component;
