DO YOU HAVE a patient with diabetes who finds it painful to use her fingertip to draw blood samples for glucose monitoring? Although blood from the fingertip most accurately reflects changes in venous glucose levels, numerous nerve endings there may make testing painful and repeated sticks can lead to local tissue damage. That's why most blood glucose meters now offer the option of using blood from the fingertips, palm, upper arm, forearm, calf, or thigh, with some limitations. Studies have shown that using the palm (at the base of the thumb) gives similar results to blood drawn from the fingertip and is less painful. If the manufacturer's instructions indicate multiple options, your patient might choose to use one of the alternate sites at certain times to reduce the number of finger sticks.
In this article, I'll fill you in on what you need to teach your patient about alternate site blood glucose monitoring and show you the technique for blood sampling from the palm.
The why and wherefore
Patients who may benefit from alternate site testing are those who test their blood glucose level often, use their fingers for their work, or feel it's too painful to test on their fingers. First, make sure your patient is a good candidate for blood glucose self-monitoring. Self-monitoring is recommended for a patient who's taking insulin or one who has:
- unstable diabetes with severe swings in blood glucose levels within a 24-hour period
- a tendency to develop severe ketosis or hypoglycemia
- hypoglycemia without warning symptoms.
For a patient taking an oral diabetic agent, blood glucose self-monitoring is also recommended during periods of suspected hyper- or hypoglycemia and when the medication or dosage is modified.
Check that your patient has discussed using her palm or another alternate site with her diabetes care provider before you teach her the technique. And make sure she understands when alternate site sampling is appropriate. Blood from the fingertip or palm more quickly reflects rapidly changing blood glucose levels, so she should use only these sites in certain circumstances. Fingertip or palm blood should be used:
- less than 2 hours after eating
- less than 2 hours after injecting rapidacting insulin
- during exercise or within 2 hours afterward
- when she's sick or under stress
- when she's experiencing symptoms of hypoglycemia
- if she doesn't recognize symptoms of hypoglycemia
- if glucose results from the alternate site don't correlate with how she's feeling.
- Alternate site blood is acceptable:
- when fasting
- before a meal
- 2 hours or more after a meal.
Explain that blood glucose readings from various sites can differ, so she should use the same type of site for all alternate testing. For example, when fingertip or palm blood isn't imperative, she may choose the forearm as her exclusive alternate site.
Step by step
Gather the blood glucose meter, test strips, and lancet device prepared for use. Have your patient wash her hands with soap and water and dry them. Then teach her to carry out these steps according to the manufacturer's instructions:
- Insert a test strip in the meter, which will turn on the meter. Verify that the code number on the display matches the code on the test strip container. If the code number doesn't appear, remove and reinsert the test strip. When you see a blood drop icon flash on the display, the meter is ready for testing.
- Firmly press the clear cap on the lancet device to your palm (the fleshy part at the base of your thumb). Using a slow up-and-down pumping action, press the cap against your palm to increase circulation underneath.
- Keep steady pressure on the area and press the lancet release button. Hold the device cap against the site for a few more seconds to let blood come to the surface.
- Touch the drop of blood to the tip of the test strip, as shown, not to the top. Look for a flashing hourglass on the meter display to indicate you've applied enough blood. If the hourglass doesn't appear, you have 5 seconds to apply more blood. (If the patient has problems obtaining enough blood for the test, “pumping” the lancet device up and down a few times will usually increase the sample size. It often takes some practice until the patient is proficient at alternate site testing.)
- Read the results on the meter display, then remove the used test strip and discard it appropriately. Record the results.
Dot your i's and cross your t's
After you've walked your patient through the technique, you'll need to:
- document the date, the time, what you taught her, and the methods used (such as demonstration and return demonstration)
- document her ability to perform the task and to verbalize when alternate site testing is and isn't appropriate
- note any materials you gave her to reinforce learning, the name of the person she should contact with problems or questions, and any follow-up needed
- list the names of family members or caregivers present during teaching.
Alternate site testing enables patients who are hesitant to use finger sticks for monitoring to test their blood glucose levels. Many patients are able to test more often by using alternate sites, usually leading to better blood glucose control. And that's what diabetes education is all about!
Learn more about it
Accu-Chek Aviva Blood Glucose Monitor Owner's Booklet
. Indianapolis, Ind., Roche Diagnostics, 2005.
Banerji MA. The foundation of diabetes self management: Glucose monitoring. Diabetes Educator
. 33(4, Suppl.):S87-S90, April 2007.
Dale L. Make a point about alternate site blood glucose sampling. Nursing2006
. 36(2):52–53, February 2006.
Smeltzer SC, et al. Brunner and Suddarth's Textbook of Medical-Surgical Nursing
, 11th edition. Philadelphia, Pa., Lippincott Williams & Wilkins, 2007:1389–1390.