BLOOD GLUCOSE METERS-No More Pokes?
Aug 6, 2010
By Trevor Shewfelt, Pharmacist at the Dauphin Clinic Pharmacy
Have you heard Trevor on the radio? Listen to 730 CKDM Tuesday Mornings at 8:35 am! We now have most of the articles published in the Parkland Shopper on our Website www.dcp.ca
The information in this article is intended as a helpful guide only. It is not intended to be used as a substitute for professional advice. If you have any questions about your medications and what is right for you see your doctor, pharmacist or other health care professional.
Terry O'Reilly is an ad producer and also comments on advertising in a radio show called The Age of Persuasion. In one episode he talked about some unwritten rules of advertising such as women in beer ads are impossibly good looking and beer is always to be served in glasses that are dripping with condensation. Id like to add one of my own. When you see an ad on TV for blood sugar testing machines, you never see anyone poking their finger.
At least a couple of times a month, I get a diabetic in the pharmacy asking for that machine that can check their sugars without a finger poke. I get the pleasure of telling them it doesnt exist. The customer is never very happy with that answer and I understand why. Poking your finger several times a day to check your blood sugar is annoying and painful. Isnt there a better way?
Checking you blood sugar without getting your finger poked is possible, but not simple. A decade ago, I was playing pool with another pharmacist and a friend of his. The friend was a graduate student in biochemistry, so I asked what he was working on. He said they had developed a piece of equipment that could test someones blood sugar without the diabetic person having to poke their finger! I was immediately interested and asked him more. He said it worked by firing infra-red light through the skin and figuring out the blood sugar from that. I was floored! This was definitely something that every diabetic would want! The researcher said the piece of equipment was about the size of a VCR and wasnt commercially available. Oh well.
Jumping back to the present, there is one poke free machine available in Canada. It is called the Guardian REAL-Time Continuous Glucose Monitoring System made by Medtronic. Before you get too excited, it is not really the finger poking replacement I was hoping for. On the positive side it has a small wireless transmitter that sends blood sugar readings to a machine without a finger poke. On the negative side, the transmitter itself is has needle that must go under the skin and you have to poke your finger up to three times a day to calibrate the meter. The Guardian wasnt really designed to replace finger pokes. It was designed to continuously monitor your blood sugar and be used with an insulin pump. One of the problems with leaving a needle in the skin to continuously monitor the blood sugar is it may cause local inflammation which can effect the blood sugar readings. That is why you still need to finger poke to calibrate the machine.
Other interesting technology involves lasers. I just like saying lasers. A hole is still poked in the skin, but it is supposed to be painless, about the width of a human hair and drilled into just the outer layer of the skin with lasers. The fluid that comes out is called interstitial fluid and can be tested for sugar. Again this is really more for continuous sugar monitoring. You need to poke the finger once a day to calibrate the machine and you have to measure the temperature of the skin to keep the readings accurate.
There was a cool sounding product in the US called the Glucowatch G2 Biographer. It generated a small electrical current the sucked sodium ions out of the skin which pulled water and glucose along. The process is called reverse iontophoresis. So the good news is it actually got a blood glucose reading without poking a hole in the skin. The problems were it often required a finger poke to calibrate it, it took 2 hours to warm up before it would work and it was very expensive. It never was marketed in Canada, and to the best of my knowledge they have stopped selling it in the US.
Then there is my favorite, infrared light. The machines to measure blood sugar with infrared light have shrunk down from the size of a VCR. And we can successfully measure other things in the blood with infrared. For a long time now we put little infrared clips on peoples fingers to measure the oxygen saturation of their blood. Unfortunately, it isnt so easy for glucose. Things like dehydration, body temperature, hemoglobin level and even medications effect how well the infrared light can measure the glucose level. So, again there are many finger pokes to calibrate the machines.
Recently, there was a new device developed by the company GlySens. It is an implantable device that is put under the skin. It has been in pigs for more than a year and seems to be working well. The best news is it doesnt seem to need calibration with finger pokes. But it has not been tested in people yet.
So maybe art really does imitate life. The women in Dauphin are impossibly good looking. The beer is always so cold it forms condensation on the glass. But as for blood sugar tests without finger pokes? Not just yet.
Link to Juvenile Diabetes Research Foundation artificial pancreas project: www.artificialpancreasproject.com
Link to Candian Journal of Diabetes article on less invasive home blood sugar monitoring: www.diabetes.ca/files/HomeGlucoseGabbaySept03.pdf
As always if you have any questions or concerns about these or other products, ask your pharmacist.