A Medical Device Daily

LifeScan has notified users of some of its blood glucose monitoring systems concerning the possible misinterpretation of their blood glucose test results if their meter is set incorrectly. The affected meters are the OneTouch Ultra, the OneTouch FastTake and the InDuo Systems. The company previously disclosed the warning last month (Medical Device Daily, May 16, 2005).

The meters were originally designed to allow the patient to select one of two units of measure to display their blood glucose results: milligrams per deciliter (mg/dL), the standard used in the U.S., and millimoles per liter (mmol/L), used in many other countries. This feature allows patients to see their test results in the units customarily used in their own country. Meters with this same feature are also made by other companies.

LifeScan said it found that it was possible for patients, in the course of setting the meter’s date and time, to accidentally change the unit of measure. If the meter is in the wrong units of measure and the patient looks only at the result registered on the meter, without reading the measurement unit displayed next to the result, he or she could misunderstand the test result. This could lead to the patient managing his or her diet or medication in a way that could result in temporary periods of high or low blood sugar. This could result, the company said, in requiring “medical intervention.”

The company also noted that a brief power loss could result from dropping the meter while in use. This could change the unit of measure and/or the code number used to program the meter to match a particular vial of strips.

It said that the misinterpretation or miscalculation could put pregnant women, children and geriatric patients at risk.

LifeScan no longer manufactures OneTouch Ultra, OneTouch FastTake and InDuo Meters that allow users to inadvertently change the unit of measure. However, many of these meters are still in use in the U.S. LifeScan said it is attempting to educate patients concerning the possible confusion in using the meters, including special instructions included in each package of the tests strips used with the meters. Patients in the U.S., it said, are being notified to be sure that their meter’s unit of measure is set to ‘mg/dL’ each time they test, and that the code number on the meter’s display matches the code number on the test strip vial each time they test.

The FDA posted the company’s notification on its web site and said it is not seeking the return or withdrawal of the meters because it believes most patients “are capable of understanding and following these instructions and, thus, they can continue to use the meters safely.”

LifeScan said it will replace the meters with newer models, if requested by patients.