Notification to all Nurses from Paradigm97...

Nurses often use point-ofcare (POC) blood glucose meters to assess patients’ blood glucose levels at the bedside. Unfortunately, a number of cases have been reported in which falsely elevated blood glucose levels resulted in inappropriate insulin administration and subsequent hypoglycemia, coma, persistent vegetative state, and even death. The falsely elevated readings were caused by a drug device interaction in patients receiving medications that contain maltose or metabolize into maltose. Examples of these products can befound in Table 1.

Some POC blood glucose meters utilize test strips with glucose dehydrogenase pyrroloquinolinequinone(GDH-PQQ) or glucosedye-oxidoreductase (GDO), which cannot distinguish between glucose, maltose, and other sugars. Glucose meters that use these types of test strips include Accu-Chek (Roche), FreeStyle (Abbott), and Ascensia (Bayer).** The maltose in the blood causes falsely elevated glucose readings in meters using GDH-PQQ- or GDO-containing test strips.When the falsely elevated readings are used to guide insulin administration, inappropriate dosing can lead to hypoglycemia. TheUS Food and Drug Administration (FDA) has identified 18 cases of hypoglycemic adverse events associated with EXTRANEAL (icodextrin), a peritoneal dialysis solution that is often delivered directly to dialysis units instead of being dispensed from the pharmacy. In seven of these cases, healthcare providers used glucose meters that reliedon GDH-PQQ- or GDOcontaining test strips. In some of the cases involving serious outcomes, staffhad been informed by patients or the patients’ families about the drugdevice interaction, but staff still reliedon erroneous blood glucose readings to treat these patients with insulin.

One of the most recent cases involved a 62-year-old dialysis patient who had been receiving Extraneal as an outpatient before hospital admission. Over the next few days, the patient’s blood showed glucose was monitored using an Accu-Chek Inform system and GDHPQQ-containing test strips. Staff recorded three elevated glucose readings, which were treated with insulin despite laboratory values that were markedly lower than the meter readings. By the end of the week, the patient died from “severe hypoxia due to untreated hypoglycemia.” Intravenous immunoglobulin (IVIG) is another drug that has been linked toserious drug-device interactions. In one case, an elderly immunocompromised patient with sepsis was treated with OCTAGAM (immune globulin intravenous [human]), which contains maltose (100 mg/mL). Glucose meters and the maltose-sensitive test strips were used to monitor his glucose levels. Since the patient’s blood glucose readings were elevated, he was started on an insulin infusion. The patientexperienced symptoms of severe hypoglycemia, which was confirmed by a laboratory blood glucose level of12 mg/dL. The patient developed irreversible neurological damage, although this outcome could not be definitely linked to severe hypoglycemia. Many practitioners remain unaware of this significant interaction, particularly those who do not routinely care for patients receiving peritoneal dialysis solutions containing icodextrin, maltose-containing immunoglobulin therapy, D-xylose for evaluation of malabsorption syndromes, and other products containing maltose. See checkitout! for ways to reduce the risk of false glucose meter readings in patients taking these medications.

** The list of products is not all inclusive. Various manufacturers, including Abbott, Bayer, Roche,CH Diagnostics, and Home Diagnostics, have glucose strips that use GDH-PQQ. Some of the manufacturers have multiple approved test strips that use this technology, so the product-line names are not all inclusive. In some cases, product lines include test strips that use more than one type of enzyme methodology. For example, some Accu-Chek strips use GDH-PQQ and some use an enzyme that is not reactive to maltose interference. In addition, manufacturers can market devices under additional brand names (e.g., some major companies also make devices sold under distributor names) without obtaining FDA clearance, so it would be impossible to create a comprehensive, up-to-date list of all devices that use GDH-PQQ methodology.

checkitout! (The drug-device interaction can occur up to a week or more after receiving medications that contain maltose or metabolize to maltose.) In this case use an alternative glucose testing method.
Establish warnings.Ask pharmacy to set up a special alert in the computer for maltose-containing medications so they can affix an alert sticker to these products. Add a cautionary note to themedication administration record and diabetic flow sheets. Place an alert sticker on the patient’s chart.
Develop protocols. Include the risk of false glucose determinations, the specific circumstances surrounding this risk, and the need for laboratory glucose monitoring, in insulin administration protocols and order sets.
Be prepared for errors. Establish guidelines for early recognition and treatment of a drug-device interactionor error (e.g., discrepancies between laboratory and glucose meter readings, symptoms of hypoglycemia or hyperglycemia).Conduct periodic reconciliation of laboratory and glucose meter readings whenever an insulin infusionis running, and take steps to verify a suspicious glucose reading.
Educate patients. Let patients know why the glucose meter or certain test strips cannot be used for testingtheir glucose levels. Tell patients to alert any staff who may attempt to use a glucose meter during the course of their treatment with involved maltose containing products.
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