Home-use blood sugar monitors not ideal in hospital surgical situations, researchers say

January 19, 2011

In surgical situations, fluctuation in patients’ blood glucose levels can be harmful, so physicians take frequent measurements to guide treatment decisions.

For rapid testing, doctors and hospitals often use the inexpensive glucose meters approved by the Food and Drug Administration for home use, but many are unaware of inaccuracies in those convenient devices that can lead to harmful treatment errors, particularly ones resulting in very low values.

Now a University of Florida College of Medicine anesthesiologist is leading a push to let fellow physicians know about the shortcomings of the home glucose meters in hospital settings, and to call the FDA’s attention to the need for better regulation surrounding their use clinically.

“They’re faster and cheaper, but they’re not always accurate,” said Dr. Mark J. Rice, who has investigated the devices. “They were regulated and approved for home use, then in stealth fashion they ended up in the hospitals.”

Today, Rice is presenting his findings on the technology, accuracy and regulation of glucose measurement devices to fellow physicians at the University Hospital Zurich Institute for Anesthesiology, in Switzerland. On Thursday, he will speak with physicians at the University Hospital Innsbruck, in Austria. Previously, Rice and colleagues published their findings in the journal Anesthesia & Analgesia.

While useful in home settings, the meters are prone to errors from a number of factors, including the presence of other chemicals or medications in the blood, and health conditions such as anemia, and that can cause problems in hospital settings. If a meter gives an inaccurately high reading, for example, doctors might unnecessarily give a patient insulin to lower , but that can make the levels truly too low and cause detrimental effects on the central nervous system. On the other hand, too-high levels can impair wound healing and alter consciousness.

One Centers for Disease Control and Prevention study found that on average, readings from some over-the-counter devices differed by as much as 32 percent from values obtained in a central laboratory.

“Dr. Rice outlined very clearly the strengths and weaknesses of the current technology used to measure glucose, so that we who use the devices are aware of the inaccuracies and pitfalls in measurement,” said Dr. Robert Peterfreund, of the Massachusetts General Hospital department of anesthesia, critical care and pain medicine. Peterfreund was not involved in the UF study.

Rice recommends that physicians confirm abnormal blood glucose meter readings using central laboratory measurements, and refrain from using the devices in clinical trials that call for accurate glucose measurements.

The issue of keeping tight control over blood sugar levels before, during and after surgery has been the controversial. A decade ago, a report in The New England Journal of Medicine indicated that tightly controlling blood glucose in the intensive care unit might reduce death rates. In response, the American Diabetes Association urged reining in blood sugar levels in critically ill patients, and doctors and hospitals have worked hard to comply.

More recently, however, studies suggest that tight control of blood glucose, as it is now performed, is associated with increased occurrence of abnormally low blood sugar levels, called hypoglycemia, and death among adults in intensive care units, and that the general population of critically ill adults might not actually benefit.

Surgical patients might experience fluctuations in blood sugar levels for various reasons. Some might have pre-existing — sometimes undiagnosed — diabetes. In addition, factors such as fasting before surgery, disruption of medication regimens, taking certain medicines, and stress can affect blood sugar levels.

“The problem is, how do you measure that?” Rice said.

Physicians can send patient samples to a central laboratory for testing, then wait for the results. Or they can use the convenient meters right at the bedside and get results within seconds.

“Turnaround time has got to be short in order to have optimal clinical benefit,’ said Peterfreund, who wrote an editorial discussing Rice’s Anesthesia & Analgesia paper. “With point-of-care devices, the turnaround time is very rapid … of course, if it’s not accurate it doesn’t help you at all.”

Explore further: Having heart surgery? Watch your blood sugar, especially if you're overweight or older

Related Stories

Be Aware of Blood Sugar Post Gastric Bypass

January 4, 2010

(PhysOrg.com) -- People with type 2 diabetes who have gastric bypass surgery often leave the hospital without the need for previously prescribed diabetes medications.

Recommended for you

How the finch changes its tune

August 3, 2015

Like top musicians, songbirds train from a young age to weed out errors and trim variability from their songs, ultimately becoming consistent and reliable performers. But as with human musicians, even the best are not machines. ...

Machine Translates Thoughts into Speech in Real Time

December 21, 2009

(PhysOrg.com) -- By implanting an electrode into the brain of a person with locked-in syndrome, scientists have demonstrated how to wirelessly transmit neural signals to a speech synthesizer. The "thought-to-speech" process ...


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.