Reduce testing pain and stop sticking your fingers!
Alternate Site Testing has been approved by the FDA. The term "alternate site testing" (AST) means using parts of the body other than the fingertips to obtain blood for blood glucose testing. With an approved glucose test meter you can check your blood sugar without the pain associated with the finger stick.
Introduction
Self-monitoring of blood glucose is an important part of the treatment plan for people with diabetes. It helps you develop your individual blood glucose profile, so you and your health care team can plan your particular diabetes management regimen. It provides you with the ability to make day-to-day treatment choices with meals and physical activity as well as with oral agents and insulin, and it helps you recognize and understand the effect of lifestyle and diabetes medication on your diabetes control.
Why is alternate site testing less painful?
Your fingertips, the key area for your sense of touch, are full of nerve endings (receptors), which make the fingertips feel pain more readily. Other body sites such as the forearm have fewer nerve endings per square inch than the fingertips, thus resulting in less pain. This can make alternate site testing with an approved meter virtually pain-free. A 2004 US diabetes patient market study showed that of patients who tested using alternative sites, seven in ten believe alternate site testing to be less painful. This graphic shows the concentration of nerve endings (receptors) in the fingertips vs. the forearm.
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Alternate site testing offers the most test sites available and gives those who have occupations or hobbies that require extensive use of their fingers another option to fingertip testing.
Where can I test using an AST meter?
Most commonly you will test on your fingertips or forearm. With some Alternate Site Test Meters, a blood sample test can be performed on the fingertips, forearms, upper arms, thighs, calves, and hands. You should always consult your health care professional for acceptable sites for your testing needs.
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When is testing on the finger preferred?
It is important to note that when your glucose is changing rapidly, there may be a difference in the glucose readings between your finger and other test sites, like the forearm, upper arm, thigh, calf, and other areas of the hand. Because blood flow to the finger is three to five times faster than other alternate sites, blood samples from the finger may show changes in your glucose sooner than the forearm, upper arm, thigh, calf, and other parts of the hand.
The possible difference in glucose readings between the finger and other alternate sites could delay your detection of hypoglycemia. Vigorous rubbing of the alternate test sites before lancing will help to minimize the difference between finger and other alternate site test results.
Testing on the finger is recommended:
1. If you think your blood glucose is low (hypoglycemia). Blood glucose that is too low must be treated right away. If you have symptoms such as weakness, sweating, nervousness, headache or confusion, follow your doctor's recommendation for treating hypoglycemia.
2. If you have a history of hypoglycemia unawareness (no symptoms when your blood glucose is low).
How would I know if I have hypoglycemia unawareness?
- Have you often obtained blood glucose readings below 55 mg/dL without any of the usual symptoms of hypoglycemia (sweating, tremors, rapid heartbeat, nervousness, extreme hunger)?
- Have you had episodes of impaired thinking?
- Have others observed you in situations where you appeared pale, tired, confused or acting as if you were in "slow motion"?
- Have you acted irritable or forgetful, even though you physically felt fine?
- Have you had difficulty managing a hypoglycemic episode, which required the assistance of others?
- Have you ever had a seizure or loss of consciousness without any warning signs?
- Do you try to maintain very tightly controlled blood sugars (often running below 90 mg/dl)?
- Have you had frequent episodes of hypoglycemia?
- Have you had diabetes over 20 years?
- Have you had a recent episode of severe hypoglycemia?
If you answer yes to any of these questions, please discuss this situation with your physician.
How do I perform an alternate site test?
The following graphic shows the general steps involved in forearm testing. First, you vigorously rub the area until it's warm to increase blood flow to the surface. Second, you lance the arm. Third, you touch the test strip to the blood drop. It's that easy. For more information on how to perform a blood glucose test, please refer to your user's guide for your meter.
Forearm Testing Example
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Important information about forearm testing
You can choose fingertip, forearm, palm, thigh, calf or foot testing with multi-site Blood Glucose Monitoring Systems. Forearm testing may mean less pain because your arm has fewer nerve endings than your fingertips. Before you try testing on your forearm, read your owner's manual to understand when and how to forearm test and talk to your health care professional.
When to forearm test
Although forearm testing can give sensitive fingertips a break from testing, forearm testing should only be used at the right times. Studies show that test results using samples taken from the forearm may differ from fingertip samples when blood glucose is changing rapidly, such as within two hours after a meal, an insulin dose or exercise.
- Only use forearm testing before a meal, an insulin dose or physical exercise, or two hours after a meal, an insulin dose or exercise.
- If you test within two hours after a meal, an insulin dose or exercise, you should test from your finger.
- When blood glucose is changing rapidly, fingertip samples show these changes more quickly than forearm samples.
- When your blood glucose is falling, testing with a fingertip may identify a hypoglycemic (low blood sugar) level sooner than a test with a forearm sample.
- You should use fingertip testing whenever you have a concern about hypoglycemia (insulin reactions), such as when you drive a car, particularly if you suffer from hypoglycemic unawareness (lack of symptoms to indicate an insulin reaction), since forearm testing may fail to detect hypoglycemia.
- If the results from the forearm do not match how you feel (high or low), test from the fingertip and use those results.
Some tips to help you successfully test on your forearm:
1. Before you test, rub your forearm.
2. Choose an area that's free of hair and obvious veins.
3. When using the lancet device, use the clear cap. This lets you view the test site so you can
see when you have an adequate blood sample from the forearm.
4. Hold the lancing device on the forearm for 5 seconds to allow an adequate blood sample to
collect on the surface. The clear cap allows you to see your sample.
Why are there differences between forearm and fingertip results?
Glucose concentrations in the body vary due to different rates of glucose utilization by different body tissues. The varying rates of glucose utilization may be due to varying amounts of muscle and fat tissue in parts of the body, muscular activity and variations in blood flow. It is not known which of the sites reflects blood glucose values of greatest physiological significance with regard to managing diabetes. However, if a person does experience differences greater than 20% between forearm and fingertip, the fingertip reading should be relied on as this is generally the location that has been used to establish doses of medication.
What is the percentage of difference when comparing results from the forearm to a result from a fingerstick test result?
For tests before meals, or 2 hours or more after a meal, the forearm and finger results should be within 20% of each other.
What if I observe a difference between forearm and fingertip results greater than 20%?
When comparing results using a sample obtained from the forearm and from a fingerstick, you should be in a fasting or pre-meal state (to have had no food in the last 2-3 hours).
If a large difference (>20%) between forearm and fingertip is observed when testing is done at the appropriate times, use fingertip testing for all treatment decisions until the reason for the discrepancies can be identified and resolved. Verify the system is performing properly using control solution. The forearm vs. finger test comparison should be tried again later to see if the same discrepancies occur. One single forearm/finger comparison should not be used to judge the success/failure of forearm testing.
Under certain conditions, blood glucose test results obtained using samples from the forearm may differ significantly from fingertip samples. The conditions in which these differences are most likely to occur are when blood glucose is changing rapidly such as during the two-hour period following a meal, insulin dose or physical exercise. When blood glucose is falling, testing with a fingertip sample may identify a hypoglycemic (low blood sugar) level sooner than a test with a forearm sample.
Which result should be used to determine how much medication to take if there is a difference between a forearm test and a fingerstick test?
If there is a difference between a result using a sample from the forearm and a result from a fingerstick test, use the result from the fingerstick.
- Under certain conditions, blood glucose test results obtained using samples from the forearm may differ significantly from fingertip samples.
- The conditions in which these differences are most likely to occur are when your blood glucose is changing rapidly, such as during the 2 hour period following a meal, insulin dose or physical exercise.
- When your blood glucose is falling, testing with a fingertip sample may identify a hypoglycemic (low blood sugar) level sooner than a test with a forearm sample.
Can sample size affect the result?
Yes, sample size can affect the result. Always follow the instructions in your Owner's Manual for applying blood to the test strip and make sure that the blood sample has completely filled the confirmation window of the test strip.
