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Description  |
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BACKGROUND OF THE INVENTION
The present invention relates to a home monitoring system including a
computer assisted reflectance photometer designed for measuring blood
glucose values at home, and for storing and transmitting these and other
data to a physician in connection with administration of treatment for
diabetes mellitus.
In recent years there has been an enormous growth of monitoring blood
glucose in the home. It has recently been estimated that 8% of the 5
million Americans currently diagnosed as suffering from diabetes mellitus
monitor blood glucose at home.
Home glucose monitoring is an attempt to institute cybernetic control in
the management of diabetes. In theory, patients monitor their blood
glucose multiple times a day and record this information in log books. The
information is then used by the patient's physician to periodically adjust
the dosage of insulin or other therapeutic agent. Sometimes, the
insulin-taking patient is given an algorithm to make insulin adjustments
himself based on the data he collects.
In order for home glucose monitoring to impact significantly on the
treatment of a given patient, one must assume that (1) the patient
monitors home glucose as prescribed using correct techniques, (2) the
patient records values reliably in a log book, (3) the patient comes to
the physician's offices periodically to review his or her data, (4) the
physician is able to make treatment recommendations based on viewing this
data, and (5) the patient is in some cases able to adjust his or her own
insulin based on this data.
These assumptions, however, frequently do not hold in practice patients
often forget to monitor their glucose at the appropriate time; or, when
they do they often use poor technique, making the values unreliable. Data
may not be recorded properly in log books. Even when data is properly
collected and recorded, most physicians cannot make intelligent treatment
decisions by reviewing pages of raw data. Finally, insulin adjustment by
the patient using data gathered from home glucose monitoring applied to an
algorithm is a process too complicated for most patients to follow.
OBJECTS AND SUMMARY OF THE INVENTION
An object of the present invention is to provide an apparatus for
accurately recording blood glucose data and other relevant treatment
values.
Another object of the invention is to provide an apparatus for processing
patient glucose data values in terms of a physician-prescribed algorithm.
An additional object is the provision of apparatus for transferring a
patient's blood glucose data values over a communications channel to a
physician's base computer station.
A further object of the invention is to provide a simpler, more reliable
blood glucose monitoring system.
According to the present invention, as embodied and broadly described
herein, a monitor is provided comprising, in combination, a reflectance
photometer for measuring blood glucose levels, a circuit coupled to the
reflectance photometer for converting the output from the reflectance
photometer to a glucose data signal, and monitor means coupled to the
circuit for storing the glucose data signal. The present invention also
provides as part of the monitor means apparatus for inputting administered
insulin data and means for comparing glucose data with the administered
insulin data, and other data (stress, exercise, dietary intake) and
outputting a recommended insulin dose based on a physician-prescribed
algorithm in response to the comparison. The circuit comprises an
analog-to-digital converter coupled to the glucose reflectance photometer
for generating the glucose data signal, and a data multiplexer coupled to
the output of the analog-to-digital converter and having an output coupled
to the monitor means, for controlling the transfer of signals between the
analog-to-digital converter and the monitor means.
In accordance with another aspect of the invention there is provided a
monitor system comprising means for measuring blood glucose levels and for
generating glucose data signals in response to the measurements, and
monitor means coupled to the measuring means and including first means for
inputting patient data, and second means for inputting physician
precription data. The monitor means stores and evaluates the glucose data
signals, patient data and physician data, and generates at least one
prescribed insulin dose value in response to evaluating the stored glucose
data signals, patient data and physician data.
Pursuant to still another aspect of the invention there is provided a
monitor system comprising means for measuring blood glucose levels and for
generating glucose data signals in response to the measurements. The
invention further includes monitor means coupled to the measuring means
and including means for inputting patient data, means for transmitting and
receiving data to and from the monitor means, means for storing physician
prescription data, glucose data signals and the patient data, and means
for generating at least one recommended prescribed insulin dose in
response to evaluating the stored glucose data signals, patient data and
physician data. Further, the system of the invention includes computing
means for receiving glucose data signals and storing patient data from the
monitor, for evaluating the data according to a physican-prescribed
algorithm and adjusting a physician insulin prescription in response to
the evaluation, and for transmitting the physician insulin prescription to
the monitor.
Additional objects and advantages of the invention will be set forth in
part in the description which follows, and in part will be apparent from
the description, or may be learned by practice of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are incorporated in and constitute a part
of this specification, illustrate a preferred embodiment of the invention
and, together with the description, serve to explain the principles of the
invention.
FIG. 1 depicts the monitor apparatus and illustrates its display, glucose
reflectometer strip guide, and input key switches.
FIG. 2 is a system-level schematic diagram illustrating the monitor system
of the invention.
FIG. 3 is a detailed schematic diagram of the elements connected to the I/O
control circuit shown in FIG. 2.
FIG. 4 is a system level diagram illustrating the physician/patient
relationship based on use of a monitor system employing a modem for
communicating with a physician base station.
FIG. 5A is a functional flow chart illustrating the hypoglycemic symptom
assessment firmware module employed in the monitor apparatus.
FIG. 5B is a functional flow chart illustrating the blood glucose
assessment firmware module.
FIG. 5C is a functional flow chart illustrating the exercise assessment
firmware module, emotional stress assessment firmware module, and illness
assessment firmware module.
FIG. 5D is a functional flow chart illustrating the dietary assessment
firmware module.
FIG. 5E is a functional flow chart illustrating the body weight recording
firmware module.
FIG. 5F is a functional flow chart illustrating the diet, exercise, stress,
illness (DESI) data evaluation firmware module.
FIG. 5G is a functional flow chart illustrating the sequence of the insulin
supplementation, basal insulin adjustment, and insulin
recording/administration firmware modules.
FIGS. 6A-6C taken together, are a functional flow chart diagram of the
supplemental insulin adjustment firmware module.
FIGS. 7A-7H taken together, are a functional flow chart diagram of the base
insulin adjustment firmware module.
FIGS. 8A-8F taken together, are a functional flow chart diagram of the
insulin recording/administration firmware module. FIGS. 8B-8D in
particular, illustrate a subfunction of the recording/administration
module for computing the current insulin dose. FIGS. 8E-8F illustrate
another subfunction of the recording/administration module for checking
the patient's data entry of insulin taken.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Reference will now be made in detail to the present preferred embodiments
of the invention, examples of which are illustrated in the accompanying
drawings.
In FIG. 1 a monitor unit 10 is shown including a keyboard 11, a light
emitting diode (LED) display 12 and a glucose reflectometer strip guide
14. The keyboard has a plurality of keys as follows. The "ON" key is
pressed to turn the monitor on. The "SE" key (Schedule entry) is pressed
to begin performing a scheduled blood test and/or insulin injection and to
log behavioral data. "UN" (UNscheouled entry) is pressed to begin
performing an unscheduled or "extra" blood test or insulin injection. "RD"
(Review Data) is pressed to look at data from previous blood tests or
insulin injections. After each blood test, the monitor will automatically
provide the previous 3-day blood sugar average for the relative time of
day. If desired, the actual numbers for each day can be displayed using
the RD key. The "X" (special functions) key controls transmission of data,
changing the speed of the display, changing the monitor clock, and
changing the monitor alarm. The "CANCEL" key is pressed whenever a data
entry error is made so that the monitor is returned to the beginning of a
procedure to allow reenter of data.
Number keys 0, 1, 2, 3, etc., are used to enter information into the
monitor, for example, weight, dietary intake, etc. The ENTER key is used
after operation of a series of number keys and functions to enter the data
into the system. ENTER also indicates "proceed to the next step." ENTER is
used only when entering numbers to record weight, blood sugar, calories,
food exchanges, doctor appointment dates, insulin doses or other
medications. Whenever <E> appears on the display screen of the monitor,
the ENTER key must be pressed following the numbers. The ENTER key is not
needed when recording data relating to exercise, emotional stress, urine
ketone levels or food intake, which all use a "1-5" scale.
At times the monitor will sequence a patient through a task, such as
performing a finger prick, or will pause for the patient to think about
the information which is displayed on a monitor screen. When the patient
has finished a particular procedure, or the patient is ready to proceed to
the next step, the patient must press the ENTER key to signal the monitor
the patient is ready. Whenever the patient sees the 21 E> on the display
screen, the patient must press the ENTER key to proceed.
"CLEAR" is pressed to clear the numbers which have been entered
incorrectly, but before the ENTER key has been pressed. This allows a
correction if the wrong numbers have been pressed for such items as
weight, blood sugar, calories or insulin dose. This key cannot be used
after pressing a number for exercise, emotional stress, food intake, or
any item measured with a "1-5" or other menu type scale. The upwards
arrow (.uparw.) and downwards arrow (.dwnarw.) keys indicate upward and
downward movement of the display. These keys are used to display previous
sequences of blood glucose tests or insulin injections.
The "YES" and "NO" keys are pressed in response to a prompt on the LED
display requiring a yes or no answer.
Referring to FIG. 2, an illustrative embodiment of the monitor system 10 is
described. In the exemplary arrangement illustrated, a reflectance
photometer 130 is provided for obtaining blood glucose values. The analog
output of the photometer is digitized by an analog to digital converter
(ADC) 58 and fed into the system through a data selector 60.
The system also employs a timer 52 and a modem-coupled I/O port including a
receiver 64 and an output driver 66. Timer 52 is controlled to give
patient alarm signals, in a manner described subsequently and the receiver
64 and driver 66 provide an I/O port for inputting physician data and for
coupling monitor data to a physician's operating system via, for example,
a telephone communication channel.
Monitor 10 includes a microprocessor (MPU) 150 for providing necessary data
storage, calculating and control functions. The system includes an
input/output controller section 150a and a data bus 156 for channelling
data to and from the MPU. Data selector 60 and a shift register 50 are
used for coupling the ADC 58, timer 52 and the modem I/O port to the MPU.
The keyboard unit 11, display unit 12, a random access memory (RAM) 152
and a read only memory (ROM) 154 are interfaced to the MPU through the
data bus 156. An audio output unit 13 is also connected to bus 156 and is
operated to provide "beep" signals to the patient during certain
operations, as described hereinafter.
The monitor may utilize, for example, a Sharp model PC 1500A microprocessor
system which has been modified by the addition of the elements shown above
I/O controller 150a in FIG. 2 and more particularly illustrated in FIG. 3.
The reflectance photometer 130 operates to allow the patient to obtain
accurate blood glucose readings simply and without physician assistance.
The patient smears a blood sample (obtained, for example, by pricking a
finger) on a conventional blood glucose test strip. After drying the strip
for a predetermined time, the patient inserts the strip in the strip guide
14 (Fig. 1) and the system automatically reads the strip and enters a
blood glucose value into the system in a manner described subsequently.
A schematic diagram of the hardware for obtaining blood glucose readings is
shown in FIG. 3. Analog data selector 60 is coupled to the
analog-to-digital converter 58, which may be a 12-bit unit identified by
the "7109" model designation. Analog data selector 60 is coupled through
inverting buffer 54 to the input pin 2 of timer 52. 8-bit shift
register/latch 50 is coupled to timer 52 and through inverting buffer 54
to analog data selector 60 and A/D converter 58. Additionally, the RS 232
receiver 64 is coupled to receive an input from a telephone modem (not
shown) and to feed the modem signal into the system via data selector 60.
R5232 driver circuit 66 is coupled to transmit RS-232 compatible output
signals to the telephone modem from the monitor system. Driver 66 is also
coupled to buffer 54 to receive RS 232 outputs from shift register 50. A
reference voltage generator 62 is coupled to analog data selector 60 and
to the optical circuit of the reflectance photometer to provide a
precision voltage reference thereto.
The reflectance photometer 130 operates to provide accurate blood glucose
readings through the use of a light emitting diode and a phototransistor
72. The patient smears a blood sample (obtained, for example, by pricking
a finger) on a conventional blood glucose test strip and follows a
sequence of computer-generated prompts displayed on display 12. After
drying the strip for a predetermined time, the patient inserts the strip
in the strip guide 14 (FIG. 1) and the system automatically reads the
strip and enters a blood glucose value into the system in a manner
described subsequently.
The analog data selector 60 is a type-4529 LSI semiconductor chip. It
controls the application of inputs to and the transmission of outputs from
the A/D converter 58. Photometer output voltages produced by
phototransistor 72, which reads the test strip, are coupled through
amplifier 73 to input pin 14 of selector 60. Selection inputs applied to
pins 6 and 7 from the channel 0 and channel 1 outputs of shift register 50
cause the signal on data selector pin 14 to be connected to output pin 10,
whereupon the photometer signal is applied to input pin 35 of the A/D
converter. The A/D converter is a type 7109 chip that digitizes the
voltage at pin 35 under the control of the MPU 150. The latter provides a
sequence of clock pulses at input C7 (FIG. 3, lower left) which is applied
through buffer 54 to A/D clocking input pin 22. The A/D converter issues a
status pulse at its output pin 2 after a number of clocking inputs. The
status signal is transmitted to the MPU via pin 9 of the data selector 60.
The number of clocks which are required to generate the status output is
representative of the level of the analog input. The MPU 150 therefore
calculates a digital photometer reading by transmitting clocking inputs to
the A/D converter and monitoring the A/D status output while counting the
number of applied clocking inputs.
The 12-bit analog-to-digital converter provides exceedingly precise
measurements of output voltages from the glucose reflectometer circuit.
Most monitors used for reading blood glucose levels are 8-bit systems and
their peripheral chips are also 8-bit devices. However, the system of the
present invention uses the 12-bit analog-to-digital converter chip's
internal clock to measure the time of discharge after a single sample is
converted. Since the rate of discharge is linear and constant, the system
derives through software control a highly accurate reading using this
technique. The MPU stores the digitized blood glucose reading under
control of firmware in a manner more fully described subsequently.
Timer 52 is used under control of the MPU 150 to provide timed alarms in
the form of "beeps" to signal the patient that various operations must be
performed. The MPU enters data in parallel to inputs 9-12 of timer 52.
This is done by feeding data through shift register 50 and applying it
from output pins 4-7 of the latter to the timer inputs. The data thus
entered sets a time value into the timer and "Channel O" signal from shift
register output 12 subsequently initiates operation of the timer. Upon
timeout of the timed interval timer 52 sends a signal to the MPU I/O
control terminal B7, whereupon MPU takes the appropriate action, such as
producing a "beep" sound through audio unit 13 and triggering a prescribed
software routine to give the patient the necessary prompts, etc.
The monitor system can be used with a communications modem to communicate
with a physician's base station over a telephone line. A modem coupled to
the telephone line supplies inputs to receiver 64, which is a type-1489
chip implementing the "RS 232" communication protocol. Received data is
channeled to MPU 150 via the data selector 60, which connects the signals
applied to its input pin 5 to MPU input B2 via output pin 9. MPU generated
data supplied on input B1 (FIG. 3, lower left) to shift register 50 is
transmitted from shift register output pin 13 and sent to the modem via
buffer 54 and RS-232 output driver 66, whereupon the data is placed on the
telephone line.
As shown in FIG. 4, a physician base computer 102 is coupled to a modem 104
amd tp a text and graphics printer 110. Physician's computer 102
implements an algorithm for evaluating glucose and patient data from the
monitor system 10. The data is evaluated according to the prescribed
algorithm, and the patient's insulin prescription may be adjusted in
response to the evaluation and transmitted to the monitor 10 via the modem
link.
The monitor 10, operating independently of the modem link allows a patient
114 to use and evaluate glucose, insulin and behavioral data on a daily
basis. Accumulated patient data is communicated to the physician's
computer 102 through the modem link and computer 102 evaluates the data to
produce a patient relink port 112 using text and graphics printer 110. The
report presents a complete display of the analysis of the data received
from the patient 114 via the monitor 10. The physician 100 interprets the
report results and depending on his analysis, may revise assessment
parameters, dietary, and/or insulin prescriptions.
The physician may then reprogram the monitor system by changing the
assessment parameters or dietary, insulin, or other prescription stored
within the monitor. This can be done by data inputs applied to the monitor
directly at the physician base station or remotely over the modem channel.
In accordance with the embodiment shown, the monitor system includes key
switches (shown in FIG. 1) for the patient to enter data indicating
whether he is making a scheduled entry, an unscheduled entry, special
functions or reviewing the data, and a number pad for a patient 114 to
enter data. In exercising such a program option, when a patient 114 is
making a scheduled entry, of which he would make up to eight scheduled
entries per day, the patient depresses the scheduled entry key switch SE.
Broadly, this option of the monitor system allows the patient to enter and
record data according to physician prescribed assessment parameters. These
may include the display of a prescribed basal insulin dose, recording
insulin doses administered, base insulin dosage adjustment,
supplementation of insulin doses to be prescribed, blood glucose, urine
ketones or acetones, assessment of exercise and emotional stress, and
assessment of body weight and dietary information. For an unscheduled
entry, the patient 114 optionally records blood glucose and/or insulin
taken during an unscheduled time period.
The use of the monitor system typically includes the operation of testing
for a blood sugar level. The patient may perform the blood sugar test
either as part of a Scheduled Entry or as part of an Unscheduled Entry. To
perform the blood sugar testing routine, the patient must have the monitor
system 10, a lancet device, a bottle of "Dextrostix" strips (or similar
type of reagent strips), a wash bottle with water and blotting paper.
Typically the patient will assemble the lancet device and then wash his
hand in warm, soapy water. The patient then removes one Dextrostix strip
from the bottle. The monitor system is turned on by pressing the ON key.
Subsequently, either the SE or the UN key is depressed. After a sequence
of preliminary prompts, the blood suger test is intitiated when the
monitor displays "PRICK FINGER <E>." This signals the patient to prick the
finger with the lancet device and obtain a drop of blood. After the drop
of blood is obtained, the patient picks up the test strip with, his free
hand and presses the ENTER key.
The monitor system proceeds to prompt, "APPLY BLOOD AT BEEP." In four
seconds the monitor produces a "beep" from its audio unit 13, which is the
patient's signal to apply the blood onto the pad of the test strip. The
monitor system then counts down 60 second intervals.
After 60 seconds, the monitor again beeps and displays the prompt, "WASH
STRIP." This is the signal to rinse the blood off the strip, using a
thorough, even wash for about 2-3 seconds. The monitor then beeps and
prompts the patient, "BLOT STRIP." The patient at this point will blot the
test strip onto a paper towel twice. Another beep is generated by the
monitor system and the prompt "INSERT STRIP <E>" is displayed. This is a
signal for the patient to insert the strip into the glucose reflectometer
strip guide 14. When the strip is properly inserted, the patient presses
the ENTER key switch.
The monitor system pauses for a few seconds, while it displays "READING
BLOOD GLUCOSE." During this time, the monitor system is determining the
blood glucose sugar value by reading the color of the test strip using
reflectance photometer 130. Subsequently, the monitor displays "BLOOD
SUGAR: [value] <E>." The monitor automatically stores the blood sugar
value into its memory 152, eliminating erroneous or deliberately
misleading recordings common with pencil and paper methods. After the
patient has seen the blood sugar value displayed, the patient is ready to
proceed to the next assessment module, and presses the ENTER key switch.
This completes the internal blood sugar test.
The reagent strips used with the monitor systems are capable of measuring
blood sugar level because the pad on the strip contains chemicals which
detect and react with glucose. When a drop of blood is placed onto the
pad, the glucose in the blood starts to react with the chemicals in the
pad. The pad begins to develop a blue color. A low blood sugar produces a
light blue color, a high blood sugar produces a dark blue color.
When using the "Destrostix" type of reagent strip, the blood must remain on
the pad for exactly 60 seconds for the pad to develop the correct color to
indicate the level of blood sugar. If a person's eyes were very sensitive
to color shades, the person could determine his blood sugar by comparing
the color of the pad with a special color chart, such as the one on the
side of the "Dextrostix" bottle. If the person examines this color chart,
the person would realize that the shades "look a lot alike" and only six
blood sugar levels are listed.
The monitor system 10 employs a special optical system, the glucose
reflectance photometer 130, previously described in connection with FIG.
3, for distinguishing a large number of color shades. Each shade of blue
or other color corresponds to a certain blood sugar level. The monitor 10
can be programmed so that other types of reagent strips can be used. In
such a case an adjustment in the A/D converter control software would also
be required to provide correct conversion values.
The results of the blood test are displayed as a number. This number
indicates the amount of glucose per unit of blood in milligrams per
deciliter, abbreviated as "mg/dl."
When a patient works with a physician, the patient and physician usually
have agreed upon certain times that the patient will routinely perfOrm a
blood test and/or take an insulin shot. The monitor 10 is programmed to
know when a patient is scheduled to perform a blood test or to take an
insulin shot. This information is entered into the computer memory 152 as
prescribed by the physician. Usually the scheduled time is not an exact
time, but is a time relative to a meal, such as before or after breakfast,
before or after lunch, before or after dinner or at bedtime. A "Scheduled
Entry" is an entry performed when the patient does a blood test or takes a
shot of insulin at a prescribed and expected time, relative to the
appropriate meal. There may be times however that the patient performs an
extra blood test, or takes an extra shot of insulin. For example, the
patient may desire to check to see if his blood sugar is low or perhaps an
infection has caused the patient's sugar to rise, suggesting the need for
an extra shot of insulin. Whenever these situations occur, they give rise
to an "Unscheduled Entry."
Each time the patient performs a scheduled entry, the monitor asks the
patient about previous insulin reactions, exercise, emotional stress,
illness, weight and dietary intake. Each of these factors may change the
patient's blood sugar.
In recording insulin reactions, the monitor system prompts the patient to
enter information about recent insulin reactions, by asking "LOW BLOOD
SUGAR SYMPTOMS SINCE LAST ENTRY--Y/N?" If a patient has not had symptoms
of low blood sugar since the last scheduled entry and the patient does not
feel he is having a reaction now, the patient enters NO to give a no
answer. If the patient has had symptoms of low blood sugar since the last
scheduled entry or if the patient feels these symptoms now, the patient
enters YES to give a yes answer. The monitor system then asks the patient
when he had those symptoms, by displaying, "LOW BLOOD SUGAR SYMTOMS
NOW--Y/N?" In response to this prompt, the patient presses NO if the
patient does not feel he is having symptoms of low blood sugar now and YES
if one feels he is having symptoms of low blood sugar.
In recording exercise, the monitor prompts the patient for information
about activity, by asking, "EXERCISE (1-5)?" The patient will then enter
the measurement of exercise or activity since the last scheduled pre-meal
entry, using the following scale:
1=substantially less exercise than usual for this time of day.
2=somewhat less exercise than usual for this time of day.
3=usual amount of and type of exercise for this time of day.
4=somewhat more exercise than usual for this time of day.
5=substantially more exercise than usual for this time of day.
Note that the patient is being asked how active he has been compared with
his usual amount of activity for the period of time since the last
scheduled entry. For example, while the patient sleeps the patient does
not exercise. The next morning, for a pre-breakfast entry, this would be
entered as a "3", if the patient actually slept through the night.
However, if for some reason the patient were awake half the night pacing
about the house, for the pre-breakfast entry the patient would enter a "4"
as a rating of the patient's night exercise.
Likewise, if the patient usually runs five miles every afternoon the
patient would enter a "3" for the pre-dinner exercise entry on days that
the patient runs five miles. However, if the patient were unable to run
one afternoon because the patient had to work late, the patient might
enter a "1" for his predinner exercise entry.
In recording emotional stress, the monitor system prompts the patient to
enter information about emotional stress by asking "EMOTIONAL STRESS
(1-5)?" In response, the patient enters the measurement of emotional
stress the patient has felt since the last scheduled entry, using the
following scales:
1=substantially less stress than usual for this time of day.
2=somewhat less stress than usual for this time of day.
3=usual amount and type of stress for this time of day.
4=somewhat more stress than usual for this time of day.
5=substantially more stress than usual for this time of day.
In recording illness, the monitor system prompts the patient to enter
information about illness by asking "ARE YOU SICK--Y/N?" The patient
presses NO if he has not felt sick since the last scheduled entry, ending
the assessment of illness. If the patient presses YES, the monitor system
displays, "HAVE A FEVER--Y/N?" The patient responds by pressing YES or NO.
If the physician desires the patient to keep track of body weight, the
monitor prompts the patient each morning before breakfast with the
question, "RECORD BODY WEIGHT--Y/N?" The patient will press either NO or
YES, depending upon whether the patient weighed himself that morning. If
the patient responds YES the monitor prompts, "ENTER WEIGHT <E>." The
patient must then enter the weight value in pounds, followed by actuation
of the ENTER key.
The monitor is able to collect dietary information in three different ways.
The physician will specify which way the monitor should ask about food
intake to reflect the way best suited for the individual patient based on
his motivation and education in quantifying dietary intake. The first
method uses a 1-5 scale to record dietary intake. If this method is
chosen, the monitor system prompts, "FOOD INTAKE (1-5)?" The patient will
then enter the number which best describes his food intake since the last
scheduled entry:
1=none or almost no food for that meal or snack.
2=somewhat less than usual (but at least 75% of usual intake).
3=usual amount and type of food for that meal or snack.
4=somewhat more than usual (but less than 25% more than usual).
5=much more than usual.
The second method uses calorie counts to record dietary intake. If this
method is chosen, the monitor system displays the prompt, "DIET
[Calories]: <E>." The patient will then enter the number of calories the
patient has eaten since the last scheduled entry.
The third method calls for an input of food exchange data.
The monitor system is capable of reviewing previous blood sugar values.
This can be accomplished by the following procedure. First the patient
turns the monitor on by pressing the ON key. Then the patient selects the
review data option by pressing the RD key. The monitor displays the
prompt, "REVIEW DATA." The display then tells the patient that the data
will be presented with the most recent first. Then the display asks the
patient to review the data one test at a time, "1-EACH", whether he wants
to review the data one test at a time, 1-EACH", or one day at a time "2-BY
DAY." In response, the patient presses "1" if he wishes to review each
blood sugar test value and associated insulin administration record, one
at a time. The patient presses "2" if he wishes to review the blood sugar
values one day at a time, viewing premeal entries of blood sugar and
insulin only.
If the patient presses "1", the most recent blood sugar and insulin levels
are displayed along with the data concerning date, time, and types of
insulin administered. For example the following information describes a
breakfast scheduled entry:
Dt15 Brk B=111 R12 N.sup.15
The date is the 15th of the month (Dt=date) and the recorded blood sugar
was 111 mg/dl. The amount of R type of insulin taken was 12 units and the
amount of N type insulin recorded was 15 units. Pressing the upward arrow
key (.uparw.) will continue to present the data moving backwards in time.
By pressing the downward arrow key (.dwnarw.), the data will be presented
moving forward the displayed time. When one has seen all the data stored
in the monitor, the display will read "END OF DATA, AGAIN--Y/N?" The
patient will press YES if the patient wants to continue viewing the
information, and will press NO if the patient does not. The patient may
press the CANCEL key to interrupt the display whenever the patient no
longer wants to look at the data. In response, the monitor system displays
"CANCEL ENTRY--Y/N?" The patient presses YES and the monitor turns itself
off.
If the patient chooses to review data under the "by day" option, the
monitor displays two lines to let the patient know how the information
will be presented. The first line indicates "PREMEAL BLD SUGAR BY DAY" the
second line will indicate "FORMAT DAY BRK LUN DIN LtN." With this option
the monitor displays only the scheduled blood sugar tests performed before
meals (PREMEAL) and at bedtime (LtN--latenight). Unscheduled blood tests
and those performed after a meal (2 hours post prandial) will not be
displayed.
The blood sugar values will be displayed in the following order:
pre-breakfast blood sugar, pre-lunch blood sugar, pre-dinner blood sugar,
then bedtime blood sugar. The data from the most recent day will be
displayed first. For example,
Dt19 112--143 95
This display tells the patient that on the 19th day of the month (Dt=date),
his pre-breakfast blood sugar was 112 mg/dl. No blood sugar test is
reported for the pre-lunch time, either because the patient did not do a
test at that time or because the pre-lunch time is not a scheduled entry
time for him. His pre-dinner blood sugar was 143 mg/dl, and his bedtime
blood sugar was 95 mg/dl.
By pressing the upward arrow key to review the blood sugar values for the
previous day, the data displayed on display screen 12 will move backward
in time. Again, when the patient has seen all the data stored in the
monitor, the display will read "END OF DATA, AGAIN--Y/N?" The patient
presses YES if the patient wants to continue viewing the information and
NO for not viewing the information. The patient may press the CANCEL key
to interrupt the display whenever he no longer wants to look at the data.
In response, the monitor displays "CANCEL ENTRY--Y/N?" When the patient
presses YES the monitor turns itself off.
The monitor also implements several special functions. These special
functions can be activated by first turning the monitor on by pressing the
ON key and then by pressing the X key. The monitor then prompts the
patient to select the function desired by entering an appropriate number:
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1 - DS Function to change the display speed.
2 - BEEP Function to change the monitor alarm.
3 - XMIT Function to transmit data to the diet
care central computer over the telephone.
4 - TIME Function to change the current date/time
information in the monitor.
5 - DATA XFER
6 - HELP
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The change speed function is activated by pressing the 1 key. The display
indicates "THE DISPLAY NOW FLASHES (pause). THIS FAST--. Y/N?"" In the
underlined blank, the system displays a number between 20 and 255, wherein
20 is the fastest speed and 255 is the slowest. In response to the patient
depressing the NO button, the monitor system prompts the patient to enter
the speed desired, by prompting "NEW SPEED (20-255):--<E>." The patient
presses the appropriate number keys, then press the ENTER key.
The monitor then flashes the previously displayed two lines across the
display at the new selected speed so that the patient can judge if the
speed is too fast or too slow. These lines include:
THE DISPLAY NOW FLASHES (pause). THIS FAST--Y/N?
The processes is repeated until an appropriate speed has been selected.
If the patient selects special function no. 2 "BEEP", a majority of monitor
alarms can be turned on and off. The monitor beeps at certain times to
make the patient aware of problems or to signal the patient to perform a
procedure. The system produces beep sounds through the operation of audio
unit 13, which is controlled by the MPU 150 and timer 52 (FIGS. 2 and 3).
This may occur as part of a blood sugar test routine, or the alarm may be
signaling the patient that it is t | | |
