Dexcom Clininical Trial

[Anne0]

I've been offered the oppurtunity to participate in a Dexcom Trial, and I'm rather psyched by the idea (heck, its the closest I've come to using a continuous glucose moniter) but I was looking at pics of the apparatus,(on CWD) and gee, that stuff look lethal. (Especially the inserter)I couldn't find much info (online) about it- would anyone know if the receiver thingie is connected to the sensor pod? I'm not sure if this thing will take off-its not even waterproof + looks bulky.(but then again...so were pumps, eons ago!)
What do you guys think?

[Rick Stockton]

AnnO, I'm an ACTUAL USER of well over a month. So, rather than point you at Forbes (???), I'm gonna tell you my experience and a few facts:

The Sensor itself is a flexible wire structure. It's *WAY* thinner than the thinnest insulin needle you can buy, I'll take a SWAG at about 33 Gage. Insertion is TOTALLY painless.

The Insertion device is huge, for 4 reasons:

(1) There's a very large plastic "wing" sticking out the side. This "wing" prevents the Spring from going off accidentally and wasting $35. It's kinda hard to remove, so I recommend that you pull the wing off BEFORE you remove the adhesive tape backing and tape the sensor base to your skin.

(2) The Sensor has a lot of adhesive tape. That's actually a VERY GOOD THING, because my last Sensor ran great for SEVENTEEN DAYS!!! (Obviously, the protocol in a Trial will be quite different... even if this Trial is for the purpose of supporting application to the FDA for 1-week approval, you won't be running it for over two weeks).

(3) The base of the Sensor has two plastic "alligator clips", for holding in the Transmitter. That makes it about 50% longer and 50% wider than a typical small infusion set (like my UltraFlex).

(4) The Insertion device is designed to hold the entire Inserter after it's pulled back, so that you can dispose of it in regular trash.

Again, insertion is painless: MUCH nicer than a new infusion set,  or a stabbing with a fresh "Ultra-fine II" 31 Gage needle.

After I put it in, there is ZERO skin reaction, ZERO itching, ZERO noticable subcutaneous disturbance... even after more than two weeks! That's totally unlike my experience with Insulin Infusion sets: With Stainless Steel infusers, I'm red and itching after a day and a half. With nylon (the Ultraflex), I have to pull it after 3 or 3-1/2 days. And I almost always know/feel where it the infuser is, I feel myself reacting to stuff.

With the Dexcom Sensor, I often have to look to see which side of my body I've placed it on. I'm COMPLETELY unaware of it's presence.
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The Receiver/Display ISN'T connected to the Sensor. You can put it on a belt clip, I personally keep it loose in a pocket. the range is about 5 feet. The black Transmitter clips directly to the Sensor, with a total height of about 8mm for the two devices combined. The edges of the Sensor and Transmitter are beveled, so clothes don't catch on it.
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Careful Placement of the Dexcom Transmitter is CRITICAL to get good results. They say "Torso, Legs, Arms, anywhere at least 3 inches from your current infusion site and one inch from any visible scars." I say that's NOT TRUE, you should go only on your Torso, and at least 4 inches from anywhere you've EVER used as an infusion site. So, if you infuse on your belly, put the Sensor on your upper butt cheeks, or on your sides (from the belt line straight up towards your arm pits, that's where I go).

There's another problem: the Dexcom goes wild and reads high if you have sweat on your skin, and maybe even high humidity, at the Sensor site. (Like, it'll say "230" when you're really 120.) Where I live, in the Nevada Desert, sweat doesn't last. But for most people, sweaty exercise is exactly when you DO want it work, and you simply can't trust it. Don't calibrate it when the site is sweaty, either, or it will read way low for the following 12 hours after it drys off.

Not having the sweat problem, and being careful with my sites, and also never squashing the sensor down against the mattress while sleeping, I've had +/- 15% or 30 points. Absolute worst reading in 7 weeks: 40 points higher than the Ultra.

With these numbers, unlike the official studies, I "extend the graph" in my head, knowing that ISF glucose is about 10-15 minutes behind blood glucose. They got somewhat worse, +/-21%, on the study documented in the current User's Guide. But they compared against YSI and One-Touch at the exact same time, ignoring the often predictable effects of the ISF time delay.
- - - - -
Typical severe (sub-50) lows per month: 8-12 (all at night)
Severe lows in June, 2006: ZERO
Expected improvement in HGbA1c: .3-.5 points

I LOVE THIS MACHINE !!!!!

[JDRF-Team-LRS]

Hi again,
I just came across this information from another source ...

"..With all the recent news about progress toward a "closed loop system", you may find this blog, written by a 30 yr old triathlete, to be informative & encouraging. Matt Vogel is using the Dexcom system, one of several now available in trials across the country. http://www.insulinfactor.com/article_dexcom.html  "

[JDRF-Team-LRS]

Hello Anne0,
So far, I have only been able to find news-wire reports on the DexCom product, and most of what I've found is aimed at investors interested in their "IPO" (initial public offering).  There are some interesting opinions included in these articles, but hardly the answers you're seeking:

http://www.forbes.com/2005/04/08/cx_sr_0408ipooutlook_print.html
http://www.smartmoney.com/onedaywonder/index.cfm?story=20060327

Here's a link to a user-conversation (from April 2006):
http://www.kweaver.org/archives/2006/04/dexcom_is_avail.html

If I were considering the opportunity that you are, I'd check out the DexCom customer service resources (surely they can send you a e-users manual so you get a feel for what's involved)
http://www.dexcom.com/html/dexcom_customer_support.html

and I'd also ask to speak to other study participants who are farther along in the process than you are.  To do so would require that the researchers ask soem folks if they'd be willing to be contacted or to contact you (HIPAA rules).  GOod luck!  I wish I had more info to share. Perhaps some among our thousands of readers will post on this topic, too.  Do let us know what you decide to do and if you go forward, we'd love to read your experiences & perceptions.