Karen R. Sando, PharmD Candidate, University of Florida College of Pharmacy, has had type 1 diabetes for nearly 16 years, diagnosed at the age of 8, and figures she has stuck her fingers, arms and hands over 29,000 times. She had a chance to use the Dexcom 7 and wants you to know the real deal. Read this article and then learn more about the Dexcom 7.
DexCom: The Real Deal
An Evaluation by a Real-Life Diabetic
Karen R. Sando, PharmD Candidate
University of Florida College of Pharmacy
Class of 2008
I am a fourth-year pharmacy student at the University of Florida. I am in my last month of clinical rotations. I am a type 1 diabetic. I’ve had type 1 diabetes for nearly 16 years, diagnosed at the age of 8. I currently use an insulin pump to manage my diabetes. Monitoring my blood glucose is as second nature to me as breathing. I test my blood sugar 6 to 8 times a day to maintain my control. I’ve tested myself in every conceivable location at every possible time with nearly every meter on the market. I’ve often wondered if I added it up, how many times have I checked my blood sugar over the last 16 years? Well, let’s say 5 checks a day for 16 years…wow that is 29,200 times! No wonder our patients fight us on checking their blood sugar! And my A1c control you ask? Well, I believe I’m doing pretty well. My A1c values have been less than 6% for several years now.
While working on my rotation I was presented with the opportunity to try out the DexCom STS Seven CGMS. I jumped at the chance. The DexCom STS Seven CGMS consists of 3 major parts: a receiver that displays your blood glucose readings and gives you a graphic trend over 1, 3, and 9 hours; a sensor which is inserted subcutaneously much like an infusion set for a pump; and a transmitter which snaps into place over the sensor, communicating values to the receiver.
The insertion of the sensor was relatively painless and very similar to the insertion of an insulin pump infusion set. However, it is manually driven, meaning you have to push the plunger down to insert the needle with the sensor. Next, the snapping in of the transmitter is not too difficult. After your sensor and transmitter are in place, a 2 hour run-in period will occur between the transmitter and receiver. At the end of this 2 hour period I had to check my blood sugar two times in a row and upload the results using DexCom’s proprietary cable. After that I was required to upload blood glucose results done on a glucometer every 12 hours. You are not able to manually enter values, which is a drawback to the product. You must have the DexCom cable.
I wore the product for 7 days, which is the lifespan of the transmitter. I felt like quite the bionic woman (pump plus sensor)! At first, I was quite skeptical. The device did not seem to be very accurate when compared to the blood glucose readings I was getting on my glucometer. Also, the shape and size of the device is slightly awkward, larger than my insulin pump. One catch with the product is the mandatory use of the One Touch Ultra glucometer as it is the only one that communicates with the receiver via the proprietary cable. As the week went on, I warmed to the product. It became quite comforting to be able to look down at the receiver and see where my blood sugar was hovering. It also provided alarms when my blood sugar was too low or too high based on my personal settings. Looking at the 1 hour, 3 hour, and 9 hour trend screens really gave me insight as to how my activities (meals, exercise, bolusing) all affected my blood sugar. And best of all, I had to prick my fingers quite sparingly, only about 2 times per day. One quirky aspect of the product I noticed during the week was the receiver will report high blood glucose readings after a shower. I checked with my glucometer to verify and the reading was not accurate. After about 30 minutes to an hour however the receiver reported a more accurate reading.
At the end of my session, I used the provided software to upload all of my readings from the week. The setup of the program and downloading from the receiver was very easy. Both can be done following easy-to-understand on-screen prompts. There were several options to review my data: glucose trend (Fig 1 and 2), hourly statistics (Fig 4), glucose distribution (Fig 3), and daily statistics. All of these options are displayed in easy-to-read graphical formats. I was able alter the number of days, day of the week, time of day, and glucose ranges to be displayed. Of the various options to review my favorites were the glucose trend and hourly statistics chart. The glucose trend chart allowed me to see all of my values plotted over time. Viewing this chart in the 7 day or session-long format is slightly confusing as there is so much data to look at. However, I found viewing this chart in the daily format was much easier, allowing me to see at what parts of the day I was having out-of-range readings. The hourly statistics chart displays all of your readings by hour. It displays the average and median for that time period as well as minimum and maximum values. This chart I felt was the most valuable to spot where I may be having trouble with either high or low blood sugars.
At the end of my 7 day session I was slightly sad to give up the DexCom. It allowed me to check my blood sugar less frequently while providing me with the peace of mind of knowing where I was at and where I might be going based on my trends. The software and viewing of my session showed me my blood sugar averages are quite good, however, I do have wide swings in variability especially around meals. I can now use this information to make more informed carb choices around my meals or adjust my doses to combat blood sugar swings. Unfortunately, the DexCom is not covered by a majority of insurance companies making it an expensive venture for the average patient. Perhaps when I graduate and start to earn some money, I will consider purchasing one. Until then…I’ll keep on checking.
Karen Sando is a 4th year PharmD candidate from the University of Florida College of Pharmacy. She will be graduating in May and has accepted a PGY-1 residency in Primary Care with the University of Florida and Area Health Education Center (AHEC) in Gainesville, FL. Karen has had type 1 diabetes for 16 years and hopes to use her personal experience with the disease to improve diabetes care. She wishes to become a Certified Diabetes Educator (CDE) and Board Certified Pharmacotherapy Specialist (BCPS) and use her expertise in clinical, community, and academic settings. Karen is also actively involved with the Florida Camp for Children and Youth with Diabetes (FCCYD).