FreeStyle Navigator(R) - FAQs - How does the FreeStyle Navigator system work?

Answers to Frequently Asked Questions
What is the FreeStyle Navigator system?
How does the FreeStyle Navigator system work?
- How far can I keep the receiver from the transmitter without missing glucose readings?
- Where can I wear the sensor?
- How big is the sensor? How deep does it get inserted?
- Can the sensor be inserted in other sites on the body?
- I have skin allergies. What is the sensor mount adhesive composed of?
- Does the FreeStyle Navigator system require calibration?
- What is Calibration?
- How do I know if my glucose level is changing?
- Why does it take 10 hours to do the first calibration?
- Do I have to carry a separate blood glucose meter?
- Is the FreeStyle Navigator Transmitter® water-resistant?
- What kind of batteries does the system use?
- What about alarms?
- What is Interstitial Fluid (ISF) and how is it different from blood?
- How accurate is the FreeStyle Navigator system? How does it compare with traditional blood glucose meters?
- Is the FreeStyle Navigator system FDA approved?
How can I get a FreeStyle Navigator system?
Additional Information for Healthcare Professionals
How does the FreeStyle Navigator system work?
How far can I keep the receiver from the transmitter without missing
glucose readings?
The receiver can receive and display glucose readings anywhere within a 10-foot
range of the transmitter. When you lose connection, the receiver beeps and lets
you know that the connection is broken. If the connection is lost, glucose
readings will not be displayed. Once you bring the receiver within 10 feet of
the transmitter, you will start getting glucose readings again
automatically.
Where can I wear the sensor?
The sensor can be worn on the back of the upper arm or the abdomen. Studies
show that there is no difference in the performance and accuracy of the system
between the arm and abdomen. You can rotate the insertion site from arm to
abdomen.
How big is the sensor? How deeply does it get
inserted?
The sensor is about the size of a dime and is made from a plastic material. The
portion of the sensor that gets inserted under the skin is less than a
millimeter wide (1 mm is about the thickness of a few strands of human hair)
and it is inserted only about 5 mm under the skin. Studies indicate that a vast
majority (80.2%) of users found the insertion no more painful than a
finger-stick test.
Can the sensor be inserted in other sites on the
body?
Abbott Diabetes Care has performed studies that demonstrate that the sensor can
safely be inserted on the back of the upper arm and the abdomen. Research
studies are not yet available to validate that the glucose results from a
sensor inserted into other sites of the body would be the same as the glucose
results from a sensor inserted in the approved sites (back of the upper arm and
abdomen).
I have skin allergies. What is the sensor mount adhesive composed
of?
The sensor mount adhesive is certified to be both latex and gluten free. It is
a medical-grade acrylic, pressure sensitive adhesive on a polyurethane film
substrate.
Does the FreeStyle Navigator system require
calibration?
Yes. The system needs to be calibrated to finger-stick blood glucose
measurements. The system contains a built-in FreeStyle® Blood
Glucose Meter for convenient calibration and confirmatory blood glucose tests.
The system has to be calibrated on average only 4 times during the entire 5-day
wear period. The system requires calibration at approximately 10, 12, 24 and 72
hours after sensor insertion. You will not see any continuous glucose readings
until the first calibration is completed successfully. When the conditions are
not conducive, the system automatically prevents calibration so that it can
maintain glucose measurement accuracy.
What is calibration?
Calibration allows the system to match the glucose readings from the sensor
with a standard reference. In the case of the FreeStyle Navigator system, the
reference is the finger-stick blood glucose measurement you take with the
built-in blood glucose meter. The system requires calibration on a periodic
basis so that the continuous glucose results from the sensor accurately reflect
the capillary blood glucose readings.
Through our clinical studies and research, we have determined that calibrating the system a minimum of 4 times (averaged over the 5-day wear period) is sufficient to provide accurate results. In fact, a typical calibration schedule does not require any calibration on the last two days of the up to 5-day wear. This is made possible by the sensor’s unique Wired Enzyme™ technology that provides a stable glucose signal.
Calibration of the system establishes how sensor data is converted to a glucose number. It is therefore important to follow the correct testing techniques when performing a blood glucose test for calibration. You can ensure proper testing technique by making sure your fingers are clean and dry, by using the correct test strip code, and by using ONLY your fingers for the blood glucose test.
Note: When your glucose levels are changing rapidly, the difference between glucose levels in capillary blood and interstitial fluid can be magnified. Therefore, it is important to remember to calibrate when your glucose levels are relatively stable. You can do this in most cases by avoiding calibration during or right after meals, exercise, or insulin dosing.
How do I know if my glucose level is changing?
FreeStyle Navigator system's TRU™ Directional Arrows show which way and how
quickly your glucose levels are changing. When your glucose levels are changing
rapidly, the arrow points straight up or straight down. In addition, there are
also built-in algorithms that detect rapid changes in glucose levels and delay
the request for calibration automatically.
Why does it take 10 hours to do the first
calibration?
Abbott Diabetes Care is committed to making its products safe for the user.
Soon after the insertion of a sensor, there are physiological processes that
happen as the sensor and the body equilibrate. These processes are part of the
body’s natural response to a foreign object. The equilibration process can vary
from one person to another and may not always happen in the same manner for any
one person. We have found through our research and studies that it is not
always easy to accurately measure glucose in the body when this equilibration
happens. Therefore, we have decided to let the system equilibrate for 10 hours
in order to ensure that the system is providing accurate glucose readings. Of
course, we recognize the importance of providing more immediate glucose
information and we are actively pursuing ways to reduce the time required to do
the first calibration without compromising the system’s accuracy.
Do I have to carry a separate blood glucose meter?
No. You don’t have to carry a separate meter with you. The FreeStyle Navigator
system contains a built-in FreeStyle® Blood Glucose Meter for
convenient calibration and confirmatory blood glucose tests. Fewer things for
you to carry around!
Is the FreeStyle Navigator® Transmitter
water-resistant?
Yes! The transmitter that is worn on the body is water-resistant in up to three
feet of water for 30 minutes. The system is suitable for everyday activities
including exercise, bathing, and swimming. The receiver which contains a test
strip port should not be immersed in water or any other liquid. Water or any
other liquid should not be allowed to enter the test strip port.
What kind of batteries does the system use?
The system uses replaceable batteries. The transmitter uses one 357 HC type
battery that lasts approximately 30 days. A 357 HC type battery is provided
with every sensor kit (containing a month’s supply of sensors). The receiver
uses two AAA type batteries that last approximately 60 days.
Energizer® brand alkaline batteries are recommended.
What about alarms?
The FreeStyle Navigator system provides you many safety alarms. There are
alarms for low and high glucose conditions. You can set the glucose levels for
your alarms between 60 mg/dL and 300 mg/dL. The FreeStyle Navigator system
provides you projected alarms that can alert you 10, 20, or 30 minutes before
glucose highs and lows. In addition, there are alarms for low battery
conditions, calibration prompts, sensor replacement, and other system
functions. All these alarms can be set to three different levels of volume—in
beep or vibrate modes—or they can be turned off entirely if desired.
What is Interstitial Fluid (ISF) and how is it different from
blood?
Interstitial fluid is the fluid in spaces between the cells in your body.
Movement of nutrients, oxygen and glucose from the blood into the cells occurs
across the blood vessel wall and interstitial fluid. Depending on how glucose
is being consumed by surrounding cells and how rapidly the glucose is changing,
there may be some differences between the glucose levels in capillary blood
(which home blood glucose meters measure) and interstitial fluid. Typically,
these differences are not significant enough to affect treatment decisions.
These differences can be magnified during conditions of rapid changes in the
blood glucose levels (for example, after eating, exercising or dosing
insulin).
How accurate is the FreeStyle Navigator system? How does it compare
with traditional blood glucose meters?
The FreeStyle Navigator system has been proven to be clinically very accurate.
In clinical studies, results from the FreeStyle Navigator system were compared
to standard reference methods that are widely accepted by the industry and
regulatory authorities. Performance evaluation of the FreeStyle Navigator
system based on these established standards clearly demonstrates a high degree
of accuracy. Typical blood glucose meters provide glucose readings at the
instant testing occurs. The FreeStyle Navigator system not only provides
continuous readings once every minute but also shows which way and how quickly
glucose levels are changing. Traditional methods of evaluating accuracy of
glucose monitoring devices are not equipped to account for this rate and
direction of glucose change. They are designed to compare point-in-time
measurements alone. This makes it difficult to compare the accuracy of a
traditional blood glucose meter and the FreeStyle Navigator system using the
same techniques. However, data from the FreeStyle Navigator system clearly
shows that the readings are very accurate throughout the entire duration of its
up to 5-day wear.
Is the FreeStyle Navigator system FDA approved?
Yes. It is approved to be used as an adjunct to traditional blood glucose
testing. Before making adjustments to treat your diabetes, you must perform a
confirmatory blood glucose test. You can use the convenient built-in
FreeStyle® Blood Glucose Meter to do the confirmatory blood glucose
testing.
For more detailed, clinical information for the FreeStyle Navigator system click here.
Tired of questions?
Want to see the FreeStyle Navigator system in action?
Call us 24 hours a day, 7 days a week: 1-866-597-5520
| * | Note: Movement of the sensor support mount or excessive perspiration at the sensor insertion site due to activities like vigorous exercise or bumping against objects may lead to poor adhesion of the support mount to the skin and cause the sensor to dislodge. If the sensor dislodges due to the sensor support adhesive failing to adhere to the skin, you may get unreliable results or no results. The system may not provide a warning in such circumstances. Choose the proper sensor insertion site when inserting the sensor and prepare the site by following the instructions for site preparation. |
Safety Information: Users should read all of the instructions in the User's Guide before using FreeStyle Navigator® Continuous Glucose Monitoring System. Adjustments to treatment should be done under the guidance of the user's healthcare team.
Indications for Use: The FreeStyle Navigator® Continuous Glucose Monitoring System is indicated for continually recording interstitial fluid glucose levels in people (ages 18 and older) with diabetes mellitus for the purpose of improving diabetes management. Readings and alarms about glucose levels from the FreeStyle Navigator® Continuous Glucose Monitoring System are not intended to replace traditional blood glucose monitoring. Before adjusting therapy for diabetes management based on results and alarms from the FreeStyle Navigator® Continuous Glucose Monitoring System, traditional blood glucose tests must be performed. The FreeStyle Navigator® Continuous Glucose Monitoring System provides a built-in blood glucose meter to confirm the continuous glucose result.
The FreeStyle Navigator® Continuous Glucose Monitoring System provides real-time readings, graphs, trends, and glucose alarms directly to the user. The FreeStyle Navigator® Continuous Glucose Monitoring System is intended to be used in home settings to aid people with diabetes in predicting and detecting episodes of hypoglycemia and hyperglycemia and in clinical settings to aid healthcare professionals in evaluating glucose control. The FreeStyle Navigator® Continuous Glucose Monitoring System is available only by prescription.
Contraindications: The FreeStyle Navigator® Continuous Glucose Monitoring System must be removed prior to Magnetic Resonance Imaging (MRI).
Prescription Device: Federal law restricts the sale of this device by or on order of a physician.
Warnings/Precautions: Infection, inflammation, or bleeding at the glucose sensor insertion site are possible risks of inserting a sensor into your skin. If you believe your results are not reliable, or are inconsistent with how you feel, perform a blood glucose mode test to measure your glucose. If the problem continues, discard the old sensor and insert a new sensor. Performance of the system under conditions of fluctuating hydration levels such as during renal dialysis has not been evaluated. Unintended dislodging of the sensor due to excessive perspiration, exercise, or bumping, may cause unreliable or no results without warning. A portion of the membrane polymer will remain in the skin each time the sensor is removed. Although no health effects were observed or reported in clinical studies, the long term effects of the sensor membrane fragments remaining in the skin have not been determined. Performance of the FreeStyle Navigator system has not been evaluated in pregnant women.
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