Note: Descriptions are shown in the official language in which they were submitted.
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METHOD AND APPARATUS FOR HEALTH SIGNS MONITORING
CROSS-REFERENCE TO REL N
S This application is a continuation-in-part of U.S. Patent Application No.
08/940,349 filed
September 30, 1997.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to monitoring the health of an
individual and, more
particularly, to remote monitoring of health signs such as temperature and
heart rate.
Z. Description of the Related Art
It is known in a hospital setting to continuously monitor various health signs
of a patient,
such as temperature and heart rate, by utilizing relatively complicated and
expensive equipment. For
example, equipment routinely employed in hospital intensive care units
includes temperature sensors
that are thermally coupled to the skin of a patient with adhesive. One or more
wires run from the
patient to a display monitoring device. Such equipment may be more intrusive
than is desired, as
it can be annoying for the patient to deal with the sensor wires that extend
from the hospital bed, but
the need for continuous monitoring and rapid reaction to changes in patient
condition make the
intrusion necessary. This is particularly the case in a hospital setting,
where changes in health signs
?5 such as temperature and heart rate can be critical. Nevertheless, the
monitoring equipment can be
sufficiently intrusive that the patient's rest can be disturbed. It would be
advantageous if the
monitoring system employed in the hospital setting was less intrusive to the
patient's comfort.
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In addition, monitoring equipment that transmits data by means of radio
frequency (RF)
signals can cause interference among multiple equipment units located near
each other, as in a
hospital environment. In addition, monitoring equipment should be readily
usable from patient to
patient, so that resources can be deployed exactly where needed and used by
different patients.
There are situations in which continuous monitoring of vital health signs in a
home setting
may be desirable. The hospital-grade equipment does not represent a viable
alternative for a home
environment, as the equipment is usually quite expensive. Moreover, the
hospital equipment is
typically much more intrusive than is necessary in the home setting, where
changes in condition are
typically not so critical that the intrusiveness of hospital equipment is
justified. In addition, hospital
14 equipment typically includes complicated connections to warning displays or
other monitoring
equipment that do not exist in the home environment. The general populace is
quite unprepared to
operate such sophisticated equipment. Moreover, most homes lack any reliable
patient assistance,
such as an in-home caregiver, who could respond to any warning signals
produced by such
sophisticated equipment.
Other equipment typically used in the home environment is less intrusive and
more simple
to use, but is not generally suitable to the continuous monitoring of health
signs. For example,
thermometers are readily available for home use, but any thermometer reading
must be manually
taken each time an individual's temperature is needed. The same is true for
heart rate, blood
pressure, and other health-related information. As noted above, the continuous
presence of health
care assistance in the home cannot be reliably depended upon for performing
such tasks. In addition,
it can be difficult to properly interpret changes in health signs, or even be
aware of changes over time
that might indicate some form of health trouble for an individual. Finally,
some monitoring Systems
are integrated with garments, that are not easily trnasferred as children grow
or circumstances
change.
From the discussion above, it should be apparent that there is a need for
convenient and
minimally intrusive monitoring of health signs, with dependable monitoring of
the health signs for
any indication of trouble. The present invention fulfills these needs:
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SUMMARY OF THE INVENTION
In accordance with the present invention, a system for monitoring health signs
of an
individual detects at least one health sign characteristic of the individual
with a health signs sensor
unit that is located proximate the individual, produces a health signal from
the health signs sensor
that indicates at least one health sign of the individual, communicates the
health signal from the
individual to a receiving apparatus over a wireless connection, provides the
communicated health
signal to a network, and processes the provided signal at a destination node
of the network to
indicate if an emergency condition exists. The system preferably sends the
health signal to a
receiving apparatus over a wireless transmission link and to a computer
network, and processes the
signal to indicate if an emergency condition exists. The components associated
with the wireless
transmission link are sufficiently small and light weight that the components
can be clipped to a
patient garment or on a harness, which can be worn by the patient without
undue discomfort. Unlike
systems that connect a patient with wires to a monitor that then transmits
information in a wireless
link, the present invention needs no wired connection to any monitoring
apparatus. In this way,
health signs of an individual are dependably monitored in a relatively
convenient and minimally
intrusive manner for any indication of trouble. This monitoring technique is
readily applied in both
the hospital environment and in the home setting.
In one aspect of the invention, the sensor unit can process the health signs
signal before
transmitting to the receiving apparatus so as to reduce the amount of data
that must be transmitted
over the wireless link. The remote node of the computer network can comprise a
multimedia server,
such as a conventional Personal Computer or similar device with audio and
video capabilities. If
desired, the computer network can comprise a network such as the Internet, and
the multimedia
server can be placed in a remote location. The multimedia server can then
communicate with other
remote locations, such as health care monitoring facilities, to transmit the
data generated by the
health signs sensor, or can control a device or appliance.
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In another aspect of the invention, each sensor unit is encoded with a unique
identification
number that is communicated whenever it transmits a signal, and the receiving
apparatus registers
the first identification number it receives when power is first applied to the
receiving apparatus. The
receiving apparatus will thereafter ignore health signs messages it detects
from sensor units other
than the one with which it is registered. This provides a convenient way to
ensure that multiple
sensor units can be used in close proximity without interference or
interruptions in service.
Other features and advantages of the present invention should be apparent from
the following
description of the preferred embodiment, which illustrates, by way of example,
the principles of the
invention.
BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 is a schematic diagram of a health signs monitoring system
constructed in
accordance with the present invention.
Figure 2 is a representation of the sensor unit illustrated in Figure 1.
Figure 3 is a block diagram of the sensor unit illustrated in Figure 2.
Figure 4 is a block diagram of the display unit illustrated in Figure 1.
Figure 5 is a block diagram of the computer port unit illustrated in Figure 1.
Figure 6 is a block diagram of the computer illustrated in Figure 1.
Figure 7 is a block diagram of the network interface unit illustrated in
Figure I.
Figure 8 is a flow diagram showing the operating steps performed by the health
signs
monitoring system of Figure 1.
Figure 9 is a flow diagram that shows the operating steps executed in
performing system
initialization and registration of the transmitting unit with the receiving
apparatus.
Figure 10 is a schematic diagram of a harness embodiment of the health signs
monitoring
system constructed in accordance with the present invention.
Figure 11 is a perspective view of the monitoring harness illustrated in
Figure 1.
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DESCRIPTION OF THE PREFERRED EMBODIMENTS
Figure 1 illustrates a health signs monitoring system 100 constructed in
accordance with the
present invention. The system 100 includes a sensor unit 102 that is worn by a
patient 104 whose
health suns are to be monitored. The health signs may include a wide variety
of patient
characteristics that indicate the health of an individual, such as
temperature, heart rate, blood
pressure, respiration, blood oxygen, moisture, muscle response, and patient
body position. The
sensor unit 102 is sufficiently small and light that it can be clipped to a
garment 106 worn by the
patient. In this way, the sensor unit will minimally intrude on patient
comfort and mobility. Sensors
extend from the sensor unit to the skin of the patient, where they are
fastened with tape or adhesive.
The health signs information from the sensor unit I02 is sent by means of a
wireless transthission
108 to a receiving apparatus 110. The receiving apparatus receives the health
signs information and
r
processes the information so that a health care provider or other assistance
can determine if a
response to the patient condition is required. In this way, the system 100
provides continuous health
signs monitoring with minimal intrusion to the patient's lifestyle.
The wireless transmission 108 can involve a radio frequency (RF) signal or
other wireless
technologies, such as the "Personal Area Network" technique available from
International Business
Machines Corporation (IBM Corporation). The wireless transmission eliminates
the hard-wired
connection from the sensor unit to a base station receiver and frees the
patient from negotiating
bedside wires that tend to get entangled. In the case of RF technology, the
sensor unit 102 includes
a small transmitter.
The receiving apparatus 110 can comprise any one of a number of alternative
receiving
devices, including, for example, a display unit 112, a computer port unit 114,
or a network interface
unit 116. Any one of these devices can serve as a means to communicate health
signs information
to a health care provider or other assistance and to determine if an emergency
condition exists. In
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addition, these units 112, 114, 116 can be integrated into a single receiving
apparatus to provide a
mufti-function receiving apparatus, if desired.
As described further below, a display unit 112 with no other functionality
communicates the
health signs information to a health care provider, such as a nurse or other
assistant, by means of a
display panel. The computer port unit 114 communicates the health signs
information to a computer
118, such as from a data port 119 through an appropriate cable 120 to a serial
port or parallel port
connection I 2? at the computer. The computer 118 includes a network interface
124 to connect the
computer with a network link 126 to a multimedia server (MMS) 128. The MMS may
comprise a
server on a wide area network, such as the Internet, or on a local intranet.
The network link 126 may
be, for example, a computer connection to a telephone line, optic cable, high-
speed wire, or other
communications link. The network interface unit 116 communicates the health
signs information
over a network link 130, such as an Internet connection, to the MMS 128. The
MMS may be
connected to one or more response devices 132, including a pager, telephone,
facsimile machine,
computer, or a device or appliance located at a health care provider or in the
household of the patient
being monitored.
Sensor Unit
Figure 2 is a perspective view of the sensor unit 102 illustrated in Figure 1,
and shows that
the sensor unit comprises a small transmitting card 202 from which extends a
connecting wire 204
that ends in a sensor pad 206. The sensor pad is attached to a location on the
patient that will permit
optimal placement for sensing the patient health signs. The location depends
on the design of the
sensor and the health signs being measured. The sensor pad 206 is typically
attached to the patient's
skin using removable adhesives that will be known to those skilled in the art.
Alternatively, the
sensor pad may be attached with cuffs or bands that ensure optimal placement.
For example, the
sensor pad may comprise a cuff that wraps around an arm or wrist to provide a
variety of health signs
signals, such as blood pressure, hear rate, respiration rate, oximetry, and
body temperature. The
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sensor pad also may comprise a saliva analysis pad lodged in the patient's
mouth. As described
further below, a communications port 212 is optionally provided to permit
interfacing the
transmitting card 210 with one of the receiving apparatus 110 (Figure 1 ), if
desired. A battery life
indicator 214 is provided along the top edge of the card to indicate battery
lifetime, as described
S further below.
The transmitting card 202 is preferably no larger than a typical pager or
matchbook. The
transmitting card is attached to a garment worn by the patient with a clip 208
that holds the garment
between the clip and the back side 210 of the transmitting card. The small
size of the transmitting
card and the clip will permit attachment at the collar of a shirt, for
example, so as to minimize
intrusion into the patient's comfort and freedom of movement. The connecting
wire 204 can be sized
to provide desired flexibility in the placement of the sensor pad 206. A wire
of approximately six
inches in length has been found sufficient for optimal placement of the sensor
pad with the
transmitting card worn at the patient's collar. If desired, the transmitting
card 202 may have a clip
or other attachment device that produces an alarm signal if the transmitting
card is removed from
the garment.
Figure 3 is a block diagram of the sensor unit 102, showing the primary
functional
components. A control integrated circuit (IC) 302 receives the health signs
sensor signal from the
sensor pad connecting wire 204. The control IC performs any processing or
signal conditioning
necessary to process the signal and produce data before providing the health
signs data to a
transmitter 306. The transmitter continuously generates a wireless signal by
which the health signs
data is provided to any one of the receiving apparatus 110 shown in Figure 1.
The wireless
transmitter can make use of conventional radio frequency (RF) transmission
techniques, which are
well-known to those skilled in the art.
Alternatively, the transmitter can make use of so-called "Personal Area
Network" technology
?5 that utilizes low-voltage of the human body to electrically transfer
information from the body of an
individual through physical contact or proximity with a receiving body. The
Personal Area Network
technology eliminates the need for electromagnetic over large distances. The
health signs
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monitoring system with Personal Area Network technology thereby is not
affected by most RF
energy, and will not interfere with the operation of RF-sensitive equipment.
The transmission
distance of the Personal Area Network technology is somewhat limited, so if
the Personal Area
Network technology is used with the sensor unit, then a patient covering such
as a blanket may act
as a receiving unit or antenna for the Personal Area Network transmitter. As
an alternative to
wireless transmission of the health signs data to a receiving apparatus, a
wired link can be provided
through the communications port 212, which is connected to the control IC 302.
The
communications port 212 receives a multi-pin connector (not shown) for a wire
cable that is coupled
to the receiving apparatus, and thereby permits the control IC to transmit the
health signs data over
a wired link.
Power for operation of the sensor unit 102 is provided by a battery 308 that
is preferably
small and with long service life. Typical batteries suitable for this purpose
include camera batteries
and watch batteries. Because of the health monitoring function of the system
100, it is critical that
the sensor unit have a able and ready source of electrical power. Typically,
such assurance would
be provided by battery monitoring circuity, with a battery charge display. A
battery monitoring
feature of the invention eliminates the need for battery charge circuitry to
detect and display
remaining battery life.
In accordance with the invention, the system 100 determines remaining battery
life by
programming executed by the control IC 302 that counts the number of signal
transmissions from
the sensor unit 102 to the receiving apparatus 110 (Figure 1). It should be
noted that, in normal
operation; the sensor unit continuously transmits health signs signals to the
receiving apparatus.
With the frequency of health signs transmission known (for example, one
transmission every sixty
seconds), and with the message length of each transmission known, it is
relatively simple to
determine the expected number of signal transmissions in a battery lifetime.
The control IC keeps
ZS this lifetime count, and decrements the expected number of message
transmissions in the remaining
life of the battery. As soon as the lifetime count of remaining transmissions
reaches a predetermined
point, such as at zero transmissions left in the count, the battery is
declared dead. The battery
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lifetime indicator 214 can be, for example, a bright LED that glows steadily
so long as time remains
in the battery lifetime count. Once the lifetime count has been reached, the
control IC 302
extinguishes the indicator light, even if there is still sufficient battery
power to light the LED. In this
way, battery lifetime can be indicated without relatively expensive battery
charge circuitry.
Display Unit
As shown in Figure 1, one of the receiving apparatus 110 that may receive the
health signs
signal from the sensor unit 102 is a display unit 112. Figure 4 shows details
of the display unit
construction.
Figure 4 shows that the display unit 112 includes a receiver 402 that is
adapted to receive
transmissions of the type sent by the transmitter 306 (see Figure 3). For
example, if the transmitter
produces radio frequency (RF) transmissions, then the receiver 402 can be a
conventional RF
receiver. The receiving unit 108 also includes a control panel 404 and a
status display:'406, which
provide a control interface through which a user provides commands and views
system operating
indications. The status display 406 can be used to display the current health
signs information, such
as current patient temperature, and if desired can also display other useful
information, such as clock
time or desired health signs signal value. If desired, the display unit can
store all display data in
memory, including clock time of recording. In addition, the status display can
be made to show
selected messages upon the occurrence of particular health signs signals, such
as a treatment for the
emergency condition. For example, if a high patient temperature is indicated,
then the displayed
message might comprise an advertisement for a fever relief medicine. Warning
messages also may
be displayed.
The display unit I 12 of Figure 4 is designed to be easily transported to any
room in which
it is needed and to be of minimum size. As a result, the display unit operates
under control of a
control IC chip 408. Thus, the display unit does not require a complicated
operating system or other
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peripheral resources that would increase the size and power requirements of
the display unit. This
ensures maximum transportability and flexibility of the system, and reduces
costs.
The display unit 112 continuously receives health signs data from the sensor
unit 102, but
may store that data for processing. That is, the display unit control IC chip
408 can be programmed
so that health sins data is stored in memory that is part of the chip and then
is processed at regular
intervals. As an example, the IC chip might be programmed so that health signs
information sent
to the display unit is stored in the control IC chip memory every ten minutes,
to provide a long-term
record of health signs information that can be analyzed to detect trends over
time that might not be
apparent over a more frequent recording schedule, or that might be tedious to
review. This can
accommodate analysis of temperature data, which might be affected by circadian
rhythms or other
factors. Thus, a temperature fluctuation that might otherwise indicate an
alarm will instead be
determined to be a result of normal circadian fluctuation. The data recording
featwe also provides
data storage that is not readily accessible by unauthorized persons.
As an alternative to using a wireless transmission means such as RF signals,
the receiver 402
can make use of the so-called "Personal Area Network" technology that utilizes
low-voltage of the
human body to electrically transfer information from the body of an individual
through physical
contact or proximity with a receiving body. The transmission distance of the
Personal Area Network
technology is somewhat limited, so if the Personal Area Network technology is
used with the sensor
unit, then a patient covering such as a blanket may act as a receiving unit
for the Personal Area
Network transmitter.
In addition, as an alternative to wireless reception of the health signs data,
a wired link can
be provided through the port 410, which is connected to the communications
port 212 of the sensor
unit 102 (Figure 2). Internally to the display unit 112 of Figwe 4, the port
410 provides its signal
to the control IC chip 408, and thereby permits the control IC chip to receive
the health signs data
over a wired link. Finally, the receiver 402 can be configured as a receiver
for radio frequency
identification (RFID) technology from Texas Instruments Incorporated, called
"TIRIS". Those
skilled in the art will recognize that TIRIS technology is currently deployed
in oil company service
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station payment systems, which include a very low power transmitter that is
passed adjacent a
compatible receiving sensor to download identification data for payment. In
the health monitoring
system described herein, such technology can be used to download
identification information for
health care personnel, such as nurses. This information can be incorporated
into the health signs
information that is transmitted to a receiving apparatus. In addition, the
TIRIS technology can be
used to farce a particular receiving apparatus identification code into the
health signs information,
as described further below in connection with the system initialization
processing of Figure 9.
If desired, the display unit 112 can incorporate an environmental sensor 412
that provides
an ambient environmental signal with which to perform attenuation and
adjudication of the health
signs signal from the sensor unit 102. For example, the environmental sensor
can comprise a
microphone to subtract ambient noise from a sensor unit microphone signal, or
can comprise a
temperature probe to compensate the sensor unit signal for ambient temperature
extremes that might
otherwise provide an inaccurate or misleading signal.
Computer Port Unit
Another one of the Figure 1 receiving apparatus 110 that may receive the
health signs signal
from the sensor unit 102 is a computer port unit 114. Figure 5 shows details
of the computer port
unit construction.
Figure 5 shows that the computer port unit 114 includes a receiver 502 that is
adapted to
receive transmissions of the type sent by the transmitter 306 (see Figure 3).
The computer port unit
operates under control of a control IC chip 504. Thus, the computer port unit
does not require a
complicated operating system or other peripheral resources that would increase
the size and power
requirements of the display unit. This ensures maximum transportability and
flexibility of the
system, and also reduces cost of manufacture.
The computer port unit control IC chip 504 can be programmed so that health
signs data is
stored at regular intervals in memory that is part of the chip, such as every
ten minutes, to provide
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a long-term record of health signs information that can be analyzed to detect
trends over time that
might not be apparent over a more frequent recording schedule, or that might
be tedious to review.
The control IC chip can be programmed to download the stored data at a
predetermined time or
recording interval, in concert with the recording schedule or at a different
interval, or the chip can
be programmed to respond to a predetermined signal that initiates download.
This feature also
provides data storage that is not readily accessible by unauthorized persons.
As with the display unit, the health signs transmissions received by the
computer port unit
114 may comprise RF transmissions, in which case the receiver 502 is a
conventional RF receiver,
or may comprise the "Personal Area Network" technology that utilizes low-
voltage of the human
body to electrically transfer information from the body of an individual
through physical contact or
proximity with a receiving body. The transmission distance of the Personal
Area Network
technology is somewhat limited, so if the Personal Area Network technology is
used with the sensor
unit, then a patient covering such as a blanket may act as a receiving unit
for the Personal Area
Network transmitter. As an alternative to wireless reception of the health
signs data, a wired link
to the sensor unit can be provided through a port 506, which is connected to
the communications port
212 of the sensor unit 102 (Figure 2). Internally to the computer port unit
114 of Figure 5, the port
506 provides its signal to the control IC chip 504, and thereby permits the
control IC chip to receive
the health signs data over a wired link.
The computer port unit 114 also includes a control panel 508 and a status
display 510, which
provide a control interface through which a user provides commands and views
system operating
indications. The status display 508 can be an alphanumeric display to show the
current health signs
information, such as current patient temperature, and if desired can also show
other useful
information, such as clock time or desired health signs signal value. In
addition, the status display
can be made to show selected messages upon the occurrence of particular health
signs signals, such
?5 as targeted advertising or warning messages, similar to those provided by
the display unit 1 I2.
In a similar fashion to the display unit 112, the computer port unit 114 can
incorporate an
environmental sensor 512 that provides an ambient environmental signal with
which to perform
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attenuation and adjudication of the health signs signal from the sensor unit
I02, such as a
microphone to subtract ambient noise or a temperature probe to compensate for
ambient temperature
extremes. In this way, the computer port unit 114 can be characterized as a
receiving apparatus 110
that integrates the display unit with additional communications capability to
interface with a
computer 118. Moreover, the system can consider a combination of multiple
health signs and
ambient signals in determining if an emergency condition exists.
As shown in Figure 1, the computer port unit 114 interfaces to the computer
118 through a
cable 120 that mns from a computer data port 119 to a serial port or parallel
port connection 122 at
the computer. Alternatively, the cable 120 can comprise a modem line or other
analog or digital
means of communicating with the computer. For example, the programming of the
IC chip 504 can
incorporate modem functionality and automatically call and obtain a modem line
to the computer
(if so connected) at regular intervals for transfer of health signs data.
Those skilled in the art will
recognize that such functionality is easily provided with the IC chip. The
computer 118 is illustrated
in greater detail in Figure 6.
Figure 6 shows that the computer 118 operates under control of a central
processing unit
(CPU) 602, such as a "Pentium" microprocessor manufactured by Intel
Corporation. The CPU
controls operation of the serial/parallel port 122 to communicate with the
computer port unit 114 and
controls operation of the computer network interface 124 to communicate with
the MMS 128. Thus,
the health signs data transmitted from the sensor unit 102 to the computer
port unit 114 is sent to the
computer I 18 over the cable 120, and then to the MMS 128.
A user controls operation of the computer I 18 through a keyboard 608 and
display 610,
which provide a means of communicating information and receiving commands from
the user. The
display may comprise, for example, a typical computer display screen such as a
video monitor or flat
pane! display. The computer 118 also includes an audio player 612, which
typically includes what
?5 is commonly referred to as a sound card, with appropriate sound drivers and
loudspeakers. The
audio player permits audible warnings to be played, for example, and can
optionally include a sound
microphone to receive audible requests from a user or from a patient.
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The operating system and applications that are executed by the computer 118
are stored in
memory 614. The memory may comprise a mixture of semiconductor memory and
other storage
media in which data, commands, and program instructions can be stored. The
operating system of
the computer may comprise, for example, the Windows 95/98/NT products from
Microsoft
Corporation or the Macintosh operating system by Apple Computer Corporation.
The executed
memory instructions of the computer 118 implement the proper processing for
communication
between the computer port unit 114 and the MMS 128. The computer also includes
a storage media
reader 616, such as a hard disk drive or a removable media disk drive. If the
storage media reader
is a removable media disk drive, then it accepts external storage media 618
such as a floppy disk or
an optical (CD or DVD) disk. Such media provide a convenient means of
receiving data or new
programming. If the storage media reader also has write capabilities, then it
can also provide a
convenient means of downloading data or programming to other computers.
From the computer 118, health signs information can be communicated to the MMS
unit 128
shown in Figure 1. As noted above, the MMS may comprise a server on a wide
area network, such
as the Internet, or on a local intranet. The MMS may have a construction
similar to that of the
computer 118, so that the MMS preferably includes at least a CPU, keyboard,
display, memory,
serial/parallel port, and network interface. The construction details of the
MMS are therefore similar
to those of the computer 118. Additionally, the MMS includes whatever
interfaces are necessary
to support communication with the response devices 132 (Figure 1), such as a
pager, telephone,
facsimile machine, computer, or a device or appliance located at a health care
provider or in the
household of the patient being monitored.
Network Interface Unit
The last receiving apparatus shown in Figure 1 is the network interface unit
116, which
receives signals from the sensor unit 102 and provides the health signs data
to the MMS 128. Figure
7 shows construction details of the network interface unit.
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Figure 7 shows that the network interface unit 116 includes a receiver 702
that is adapted to
receive transmissions of the type sent by the transmitter 306 (see Figure 3).
A network interface 703
permits the unit 116 to provide health signs data to the network connection
130. The network
interface unit 116 operates under control of a control IC chip 704. Thus, the
network interface unit
does not require a complicated operating system or other peripheral resources
that would increase
the size and power requirements of the unit. This ensures maximum
transportability and flexibility
of the system, and also reduces cost of manufacture.
The nertvork interface unit control IC chip 704 can be programmed so that
health signs data
is stored at regular intervals in memory that is part of the chip, such as
every ten minutes, to provide
a long-term record of health signs information that can be analyzed to detect
trends over time that
might not be apparent over a more frequent recording schedule, or that might
be tedious to review.
The control IC chip can be programmed to download the stored data at a
predetermined time or
recording inten~al, or the chip can be programmed to respond to a
predetermined signal from the
receiving unit that initiates download. This also provides data storage that
is not readily accessible
by unauthorized persons. As with the display unit and the computer port unit,
the network interface
unit can be programmed to automatically obtain a network connection and
transfer health signs data
at regular inter<~als.
As with the display unit, the transmissions received by the network interface
unit 116 may
comprise 1tF transmissions, in which case the receiver 702 is a conventional
RF receiver, or may
comprise the "Personal Area Network" technology that utilizes low-voltage of
the human body to
electrically transfer information from the body of an individual through
physical contact or
proximity with a receiving body. As noted above, the transmission distance of
the Personal Area
Network technology is somewhat limited, so if the Personal Area Network
technology is used with
the sensor unit, then a patient covering such as a blanket may act as a
receiving unit for the Personal
Area Network transmitter. As an alternative to wireless reception of the
health signs data, a wired
link to the sensor unit can be provided through a port 706, which is connected
to the communications
port 212 of the sensor unit 102 (Figure 2). Internally to the network
interface unit 116, the port 706
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provides its signal to the control IC chip 704, and thereby permits the
control IC chip to receive the
health signs data over a wired link.
The network interface unit 116 also includes a control panel 708 and a status
display 710,
which provide a control interface through which a user provides commands and
views system
operating indications. The status display 708 can be an alphanumeric display
to show the current
health signs information, such as current patient temperature, and if desired
can also show other
useful information, such as clock time or desired health signs signal value.
In addition, the status
display can be made to show selected messages upon the occurrence of
particular health signs
signals, such as targeted advertising or warning messages. If desired, the
network interface unit 116
can incorporate an environmental sensor 712 that provides an ambient
environmental signal with
which to perform attenuation and adjudication of the health signs signal from
the sensor unit 102.
For example, the environmental sensor can comprise a microphone to subtract
ambient noise from
a sensor unit microphone signal, or can comprise a temperature probe to
compensate the sensor unit
signal for ambient temperature extremes that might otherwise provide an
inaccurate or misleading
1 S signal.
Operation of the Health Signs Monitoring System
Figure 8 is a flow diagram that shows the steps performed during operation of
the health
signs monitoring system constructed in accordance with the present invention.
In the first step,
represented by the flow diagram box numbered 802, the system is initialized as
electrical power is
applied. As described further below, initialization involves one or more
sensor units making their
presence known to a receiving unit. It should be understood that a health
signs monitoring system
in accordance with the present invention includes a sensor unit and one or
more receiving apparatus,
~ 5 which transmits health signs data to a network computer such as the MMS.
Each receiving apparatus
incorporates a display. Thus, the processing of the initialization step (box
802) involves displaying
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health signs information and establishing communications between the sensor
unit and the receiving
apparatus.
In the next step, represented by the flow diagram box numbered 804, health
signs information
is sent from the MMS unit to the network. The sending of information can occur
at regular time
S intervals, or whenever there is a need to convey such information, such as
when an emergency
situation exists or when trouble is indicated. The network can comprise a wide
area network, such
as the Internet, or can comprise a local network such as an intranet. The
network destination for the
information may be a monitoring facility staffed by persons who can
appropriately respond to the
information, or may simply be a computer in another room of the household
where the transmitting
unit is located.
In the next step, represented by the decision box 806, the system determines
whether an
action should be performed in response to the health signs information. This
decision must be made
because it is contemplated that monitored health signs information will
typically not require any
action beyond normal recording functions that might be desired. Thus, if no
such extraordinary
action is required, a negative outcome at the decision box 806, then
processing returns to~the sending
of health signs information at box 804. If the health signs information
indicates that some action is
necessary, a positive outcome at the decision box 806, then processing
continues at the flow diagram
box numbered 808, which involves responding to the health signs information.
The processing of the information sending at box 804, the decision making at
box 806, and
the response to information at box 808 may involve a variety of potential
scenarios. If the health
signs sensor includes a temperature sensor, for example, then the decision may
involve a threshold
temperature above which trouble is indicated, or a change in magnitude over a
predetermined time
that indicates trouble. The monitoring system may account for changes in
circadian rhythm by
checking time-of day before indicating whether the body temperature of an
individual is too high.
That is, body temperature in the early afternoon might be expected to be
higher than the body
temperature in the late evening. Therefore, detected body temperatures might
not trigger an alarm
condition at certain times of the day, but might trigger an alarm at another
time of day. If the health
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signs sensor is a microphone, then the alarm decision may involve a
predetermined volume level or
a predetermined rate of change or magnitude of increase in volume, above which
trouble is indicated.
A noise level detected by the microphone that is greater than the threshold
predetermined level will
be interpreted as a sign of trouble. The health signs sensor may be a
combination of position or
movement sensors, in which case the threshold detection may involve sensor
orientation,
acceleration, or other position change that indicates an undesired change.
Thus, inputs from multiple sensors may be considered in determining if an
emergency
condition exists. A detected elevation in heart rate may be checked against
body temperature, or vice
versa. as the nvo are known to be interrelated. In addition to data values or
magnitudes, the system
I O may consider the magnitude of change or rate of change in a signal.
In the preferred embodiment, the sending of infonmation at the flow diagram
box numbered
804 from the MMS unit to the network may involve some decision making at the
receiving unit or
the MMS unit. The receiving unit or MMS unit may receive temperature data or
heart rate data, for
example, but might not send all such received data to the network. Rather, the
receiving unit or
1 S MMS unit can first process the data to make an alarm or emergency
condition determination.
Similarly, the receiving unit or MMS unit may receive sound or position
information, from which
it will determine whether an alarm should be delivered. In this way, some
level of operating
intelligence would be present in the receiving unit or MMS unit to decide if
the health signs
information sent to the network (box 804) would consist of an alarm signal or
a "clear" signal. Even
20 in the absence of an alarm signal, the sensor unit sends health signs
information to the receiving
apparatus. For example, by default, health signs information is sent from the
receiving apparatus
to the MMS unit at least once every half hour. An emergency condition or other
sign of trouble
determined at the receiving apparatus results in an immediate transmission of
information to the
MMS. The data that is sent to the MMS comprises the prior half hour of health
signs data. In the
25 preferred embodiment, the MMS stores such data for each patient, so as to
create and maintain a
database of patient information.
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In addition to operating intelligence at the receiving unit or MMS unit, there
may be some
level of operating intelligence at the transmitting unit. The intelligence
included in the transmitting
unit, for example, may be sufficient to screen or filter the temperature and
heart rate data. In that
circumstance, the transmitting unit might receive temperature data or heart
rate data, but would not
send all such data to the receiving unit. Rather, the transmitting unit itself
might include operating
intelligence, or programming, that would check for rate of change or magnitude
of reading before
sending health signs information to the receiving unit. In that case, the
health signs information sent
from the transmitting unit to the receiving unit indicates whether an alarm
condition is present and
does not necessarily include raw data. As above, this consen~es transmission
bandwidth and reduces
energy consumption. This is especially important for the transmitting unit,
which depends on battery
power for operation.
The response to the health signs information at box 808 takes place after the
information is
sent over the network by the MMS unit to a destination net<vork node. The
response, however, may
involve action at the site of the transmitting unit and receiving unit. For
example, the health signs
information may indicate that an individual's heart rate is elevated. The
response at box 808 may
involve controlling a home appliance such as by automatically reducing a home
heating thermostat
or turning on cooling equipment, or may involve contacting local paramedic or
ambulance services.
The intelligence to determine that a reduction is temperature is called for
and to generate a command
to make such a reduction may reside in the destination computer at a network
node. Thus, the
automatic response to the health signs information may include automatic
adjustment of household
appliances or systems. If such automatic response is desired, the receiving
unit or MMS unit will
be adapted to control such external devices.
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Initialization of Communications and Registration of Transmitting units
As noted above, initialization of the system involves the establishment of
communications
between a receiving unit and a transmitting unit. Figure 9 is a flow diagram
that shows the operating
steps executed in performing the initialization and subsequent operation.
In the first step, electrical power is applied to the receiving unit. This
step is represented by
the flow diagram box numbered 902. The receiving unitwext waits to receive a
transmitted message
from a transmitting unit, as indicated by the flow diagram box numbered 904.
In accordance with
the preferred embodiment, the control IC chip of each transmitting unit is
encoded with a unique
identification number at the time of manufacture. Thus, the particular
transmitting unit is easily
identified during its operation life. The transmitting unit identification
number is sent by the IC chip
with every transmission, so that a receiving unit can immediately identify the
source of a health signs
information message. A receiving unit registers the first transmitting unit it
identifies after electrical
power is applied to the receiver. Upon each power initialization cycle, the
receiver again performs
the registration function to associate itself with a particular transmitting
unit. This is useful for
operation in a crowded environment, where multiple transmitter-receiver pairs
may be in close
proximity and may use the same communications channels. The identification
number pen~nits
identification of appropriate transmitting units, and exclusion of messages
from all others.
Thus, when a transmitted message is received at a receiving unit, the
receiving unit
determines if it should process the message by first checking to determine if
it has registration
information from any transmitter. This processing is represented by the
decision box numbered 906.
If no transmitting unit is registered, a negative outcome at the decision box
906, then the receiving
unit registers the transmitter that sent the message, as represented by the
flow diagram box numbered
908. To register the transmitting unit, the receiving unit obtains the control
IC identification number
of the transmitter from the received message and stores it in memory or a
register of the receiving
unit.
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If there is a transmitting unit already registered, an affirmative outcome at
the decision box
906, then the control IC identification number of the transmitter will already
have been stored in
memory or a register of the receiving unit, and the receiving unit therefore
next checks to determine
if the registered transmitting unit is the one that sent the received message.
If the received message
is from the registered transmitting unit, an affirmative outcome at the
decision box 910, then the
receiving unit processes the received message. This processing is represented
by the flow diagram
box numbered 912 and can comprise, for example, the actions described at box
808 above in
conjunction with Figure 8. The system processing then continues with listening
for more transmitted
messages at the flow diagram box numbered 904. If the received message is not
from a registered
transmitter, a negative outcome at the decision box 910, then processing
continues with listening at
box 904 without processing the received or detected message.
Alternative Embodiment: Harness Unit
Rather than clipping the sensor unit illustrated in Figure 1 to a garment, a
sensor unit can be
integrated with a harness unit. Figure 10 shows a health signs monitoring
system 1000 constructed
in accordance with this alternative embodiment of the invention. The system
1000 includes a
harness unit 1002 that is worn by a patient 1004 whose health signs are to be
monitored. As with
the clip-on system, the health signs may include patient temperature, heart
rate, blood pressure,
respiration, oximetry, and sounds or noises in the vicinity of the patient
that might indicate trouble
or the need for attention. Health signs information from the harness unit is
sent by means of wireless
transmission 1006 to a receiving apparatus 1008 that processes the
information. The receiving
apparatus may comprise, for example, any one of the apparatus 1 I2, 114, 116
described above in
conjunction with Figure 1.
Figure 11 shows the harness unit 1002 in greater detail. In normal use, a
patient's arms are
slipped into soft loops 1102,1104 and a slip clasp 1106 is adjusted so the
harness unit is comfortable
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the patient has fallen or rolled over. Such patient position information can
be critical under some
circumstances, such as with small children or the elderly.
If the sensors 1108,1120 are not constructed as sensor units 102 (Figure 1 )
with transmitters,
then the harness unit 102 includes a transmitting unit 1122 that receives the
health signal from the
sensors 1108, 1120 and transmits the signals) to the receiving apparatus 1008
(Figure 10). The
transmitting unit can be positioned on top of the individual's shoulder, or
can be placed on the
outside of one loop or the other, for greater comfort in wearing the harness.
The transmitting unit
can make use of conventional radio frequency (RF) transmission techniques,
which are well-known
to those skilled in the art. Alternatively, the transmitting unit can make use
of so-called "Personal
Area Network" technology that utilizes low-voltage of the human body to
electrically transfer
information from the body of an individual. That is, the wireless transmission
link can comprise
Personal Area Nertvork technology that eliminates the need for electromagnetic
transmission, such
as radio frequency (RF) signals. The health signs monitoring system with
Personal Area Network
technology thereby is not affected by most RF energy, and does not interfere
with the operation of
RF-sensitive equipment.
The system described above provides convenient and minimally intrusive
monitoring of
health signs, with dependable monitoring of the health signs for any
indication of trouble in the
home environment and in the hospital environment. In accordance with the
invention, health signs
of an individual are detected with health signs sensor unit producing health
sign characteristics of
the individual, which sends health signals to a receiving apparatus over a
wireless connection and
to a computer network. The system then processes the signal at a remote node
of the computer
network to indicate if an emergency condition exists and thereby permits
dependable monitoring of
an individual's health signs in a relatively convenient and minimally
intrusive manner.
Other features may be added io a health signs monitoring system without
departing from the
?5 teachings of the invention. For example, the analysis of health signs may
comprise analysis of
detected sound that is displayed in a graphical format, with the graphical
representation data
transmitted over a network or via modem. An emergency condition may then be
triggered, as
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appropriate. One implementation of such an analysis feature may involve a
microphone detecting
heart and lung sounds, and producing a graphical display for analysis. The
sound data can be stored
and any anomaly can trigger an emergency condition notification. In addition
to the monitoring
function, the system can perform analysis of captured data on demand. For
example, the system can
be constructed to permit comparison of health signs data with data from a
database to make a
determination of emergency condition. In particular, the system may capture
image data with a
video camera and the image data can be compared to stored images to determine
if a rash, for
example, comprises an emergency condition. Other devices may physically
initiate health signs data
for analysis, such as a device that can be placed on the body to prompt a
reflex action from the knee
or ankle. Sound data can be collected, if desired, as described above.
The present invention has been described above in terms of presently preferred
embodiments
so that an understanding of the present invention can be conveyed. There are,
however, many
configurations for client-server computer systems not specifically described
herein but with which
the present invention is applicable. The present invention should therefore
not be seen as limited
to the particular embodiments described herein, but rather, it should be
understood that the present
invention has wide applicability with respect to client-server computer
systems generally. All
modifications, variations, or equivalent arrangements and implementations that
are within the scope
of the attached claims should therefore be considered within the scope of the
invention.
