Tiina Jansson and Tiina Kupiainen
Introduction
It is estimated that over 500 000 people in Finland have diabetes. It is a disease where the amount of glucose in plasma is elevated. The aim of the treatment is to avoid complications caused by either hyperglycemia with any diabetic patient or hypoglycemia with patients that use medication that lower blood glucose. (1.) Ordinary blood glucose meter, which measures the blood glucose from capillary blood taken from tip of the finger, is a common way to monitor person’s blood glucose. These meters are used in all health care areas from emergency rooms to home self-monitoring and in multiple other health care settings (2). Blood glucose meters must be the first few medical devices nursing students get to use from early on in the studies and in summer jobs in the health care field. Also as said earlier, it is a widely used device which surely will be familiar to us also later as Registered Nurses despite where we work. We think that understanding how blood glucose meters work and knowing what some possible issues are regarding their safety and usability, one can provide safe care and correct treatment. As there are several different brands of meters on the market we randomly chose one, Bayer’s Contour Next, to use as an example.
How does it work?
Together with the blood glucose meter, one needs also a lancet, gauze and a test strip to find out the blood glucose level. A test strip is placed on the blood glucose meter and the meter will show when it is ready to investigate the blood. To produce the needed blood sample for the meter, one should lancet a fingertip where a drop of blood can be harvested. The test strip, now attached to the meter, is then brought close to the drop of blood and the meter will automatically suction a needed amount inside the test strip. After few seconds the meter will show the result on its screen. In Finland, results are commonly shown in millimoles per liter (mmol/l) but it can be shown also as milligrams in deciliter. The device will shut down when the test strip is taken out. One may also for example scroll through older results and set notifications on the meter. (3.)
In some meters, there are enzymes in blood test strip which react with the glucose that is found from the patient’s blood sample. Enzymes react with the sample and can either change the color and indicate the amount of glucose in the sample or form electric current that enables the meter to read the result. (2.) The Contour XT blood glucose meter measures the electrical charge between reactants from blood’s glucose and the electrodes on the test strip (3).
Usability and safety
Nurses and other health care professionals need to understand that care must be taken when measuring blood glucose. The most common place to lancet the skin is on the finger tips, specifically on the side of the fingertip. Sometimes other areas such as arm or thumb side of the palm may be used. It should be noted, that low glucose measures can only be detected on the blood from the fingertips. Blood sample is to be taken from clean and warm hands on a place where skin is intact and healthy. After puncturing, the first drop of blood should be wiped away to avoid possible little contaminants from disrupting the measuring process. Milking the finger or trying to push blood out is bad practice as it may result in interstitial fluid in the sample, which can cause false readings. (4.)
The test strips are for single use and must be stored as ordered by the manufacturer. This usually means storing them in their container in a cool and dry place away from direct sunlight. Test strips also have a use by -date which should not be exceeded. (4.)
Blood glucose meters should be calibrated and tested as advised by the manufacturer to make sure they are in good working order and provide correct readings. Meters should be stored and cleansed correctly too. (3.)
As blood glucose meters are small medical devices they are easy to take along to ambulances and for home visits by nurses and other health care professionals. Storing at hospital’s cupboards will not require heaps of space. Self-care is easier when one does not need to carry big and multiple gear to manage their condition. Though, the size may be difficult to handle for someone with certain impairments such as poor vision or rheumatic hands.
Future views
Even someone does not suffer of diabetes one can imagine how frustrating it is to live with the condition only thinking about the measuring of blood glucose level. Surely no one would like to puncture themselves multiple times a day for year and years! Luckily, health technology is looking for new ways to treat conditions such as diabetes. Some continuous blood glucose meters are already available on the market. For example Dexcom G5 Mobile device measures blood glucose using a cannula inserted into sub cutis for a longer period of time and sends the reading to your smart phone (5). In Vaasa University, students have innovated a sticker which measures blood sugar on the skin. An application helps to follow the trend of results on a mobile. (6.)
Bayer’s Contour also provides some future views for diabetes care. CONTOUR NEXT ONE meter and CONTOUR® DIABETES mobile application helps to keep on track with the condition. The meter can be connected to the mobile application using Bluetooth connection. This meter also allows a longer time to add more blood in the test strip in case the drop used did not provide enough to prepare a result. This can reduce the amount of re-puncturing for a better sample. The results can be scrolled on the mobile phone and it shows for example how one’s lifestyle affects the blood glucose readings in the longer time period. (7.)
But there hopefully is a puncture free future for diabetes patients waiting ahead! Researchers of University in Bergen are trying to produce insulin secreting cells using person's skins cells and stem cell technique. These insulin secreting cells could be implanted on each individual diabetic patient and they would provide the patient with right doses of insulin. (8.) The future of diabetes care is headed towards direction, where one no more has to lance their finger and inject insulin. And this is great news for everybody!
References
1. Käypä hoito -suositus 2016. Diabetes. Suomalainen Lääkäriseura Duodecim.
2. Tonyushkina, Ksenia – H. Nichols, James H. 2009. Glucose Meters: A Review of Technical Challenges to Obtaining Accurate Results. Journal of Diabetes Science and Technology. 3 (4). 971–980.
3. Bayer 2014. Contour XT Verensokerin Seurantajärjestelmä. Käyttöohje. Online document. <http://diabetes.ascensia.fi/Documents/User%20guides%20and%20QRG/Contour%20XT_2014.pdf> Accessed 5.10.2017.
4. Sampolahti, Eija 2015. Verensokerin mittaamisessa tekniikalla on väliä. Diabeteslehti. Online document. <https://diabeteslehti.diabetes.fi/blog/2015/11/06/verensokerin-mittauksessa-tekniikalla-on-valia/>
5. Dexcom, Inc. 2017. Tutustu jatkuvatoimiseen Dexcom G5® Mobile -glukoosinseurantajärjestelmään (CGM). Online <https://www.dexcom.com/fi-FI> Accessed 5.10.2017.
6. Ruokari, Elina 2016. Yliopiston ja MIT:n käyttäjäinnovaatiokurssi: Ratkaisuja diabeteksen hoidosta lastenvaatepalveluun. Online document. <http://www.uva.fi/fi/news/innovaatiokurssi/> Vaasan yliopisto, University of Vaasa.
7. Ascensia Diabetes Care Finland Oy. Contour Next One Verenglukoosin seurantajärjestelmä. Online. <https://www.contournextone.fi/> Accessed 6.10.2017.
8. MEDICA Magazine. Transforming skin cells to insulin. Online. < https://www.medica-tradefair.com/cgi-bin/md_medica/lib/pub/tt.cgi/Transforming_skin_cells_to_insulin.html?oid=85677&lang=2&ticket=g_u_e_s_t> Accessed 6.10.2017.