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Clotted Dexcom Sensor.

(That's easily one of the grossest blog post titles I've had in the past seven and a half years.  Clotted?  Blech.  Sorry about that.)

Last week, I needed to give the real estate on my thighs a little breathing room, so rotated my Dexcom sensor up north to live on the back of my right arm for a few days.  Chris helped me out with the sensor application, with me preparing my skin, sticking the adhesive patch where I want it, and then asking him to, "Oh, do it carefully okay because it might pinch a little and ..." as he unclips the sensor applicator after half a second and says, "It's done."  (When I'm not controlling the needle, I bug out.  Pain management control freak, right here.) 

"Oh shit ... it's bleeding," he said, looking down at the sensor sans transmitter, and we both watched the space beneath pool with blood.

"Eh.  Hopefully it still decides to work.  Can you snap the transmitter in, and I'll fire it up?"

We finished up our respective tasks (he winced when he clipped the transmitter in, expecting it to hurt me, and I queued up the new sensor.  And for a week, this thing gave me spot-on results.  Meter said 183 mg/dL?  The Dexcom gave the exact same result. Meter claims 89 mg/dL?  The CGM confirmed that number, along with the added clue of a downward sloping arrow.  This sensor was, by far, the most accurate one I've seen for the G4.

Which is why I was so surprised (and horrified) to pull the sensor out last night and see the nastiest blood clot stuck on the end of the sensor wire, and dried blood pooled in the sensor base.

Oh effing EW.

(This post has officially become a gross post ... a "grost.")

My faith in the G4 is now that much stronger ... even when I'm working with a clotted sensor, it still fires out some on-point results.  Now if only my pancreas would get on this "I work despite being slightly compromised" bandwagon ...


Medtronic MM sensor users have sworn, for years, that bloody sensors give the best results, and last the longest!

barft at your grost.

(not really but yikes.)

Maybe it's the diabetic in me, but I find this way cooler than gross :)

Hi Kerri-
Really interesting! I'm a sensor technology developer and I have a couple theories on what you experienced. One thing I've noticed in sensor testing is that Site of implantation/injection can be very influential. I would encourage you to track the sensor site vs. Sensor performance. Although it seems counter intuitive, there may be less micromotion and torsion on a sensor placed on the arm vs the trunk. Grosts are super useful! Keep it up :)

Had the exact same thing last night when I removed my sensor... dried blood. Yuck. I winced while I investigated the removed sensor. I never noticed any blood when I put it on though. Sensor worked well all week and didn't hurt so I figure what I didn't know really didn't hurt me (wincing aside).

Ew ew ew ew.

With that out of the way... I find that I get way better accuracy on the backs of my arms than anywhere else.

Hmm, almost makes me want to aim for a vein!... Nice grost. :P

I'm glad the sensor worked for you, but just as a FYI - I've had two sensors immediately pool with blood and both times when I called DexCom they sent out replacements that day. So, if you don't want to wait and see and/or if the blood freaks you out, just call DexCom and they will send new ones.

The same thing happened to me with the sensor I am currently wearing. I applied it to my arm and immediately noticed blood pooling under the tape. As this was my last sensor I decided to leave it on and see what happened. Almost 7 days into and it has been working fine:)

I am a new CGM (dexcom) user. I have stayed on my abdomen since that is the recommendation. Are there sites that provide better accuracy that people have had good experience with?

I had bleeding on the back of my arm happen 3 days ago - unfortunately 1/2 way through start-up I got the "???"... It was suggested to me I should've attempted a re-start, but I was pretty mad at that point and tore it off :(

When this happens to me I stick a q-tip in the tiny little hole before putting the transmitter on to soak up the blood. Not medical advice. PWD advice :)

Fyi, clipping the transmitter in is super easy if you use the little lever at the back of the adhesive assembly device. We'd been painfully pushing the transmitter into the sensor against the body to clip it in for years but realized when we got a g4 that the little arm that hangs off the edge of the disposable piece (it's one of the last things you need to remove) is meant for clipping the transmitter in painlessly. It really works-- try it if you haven't!

I use minimeds sensor and would estimate that I get this with about 40% of my sensors. They usually work fine unless you get a real gusher. Is discussing gushers gross enough for the grost?

Kerri-- would live to know where you had it on your thigh as I've been too chicken to try anywhere else besides the abdomen thus far. And on your arm... Upper backside? Thanks for sharing!

I use the MM sensor, not the Dex (which you know, but for others reading) and this happens to me every so often. I blot with a tissue until the bleeding stops, then attach my transmitter. And yes, I always get stellar readings after I've had a bleeder. And yes, it's terribly gross upon removal to see all that clotted blood, and usually a big bruise too!!

hey Kerri,

I'm still pretty new to pumping but am interested in your comment that you are a pain management control freak. Needles with pens I could control COMPLETELY how fast they went in in case it was sore. Now i have an animas vibe which i really like EXCEPT putting in a new site.... i sit and try to make the silly thing go "thunk" but feel like it takes quite a large amount of mind over matter as i don't feel nearly as in control with a spring loaded thing that goes thunk than a needle i controlled completely... are you pain management freak who has a way of getting round this? did it freak you when you first had a spring loaded thing for your pump?

Its like a car wreck, I can't look away!

Nah, it's not that gross, or maybe it's because I've been there. :) My husband is the same way with the sensors and I, too, am a "Pain management control freak". :)

I always use my arms and get great results. And, the grosser the insertion process, the better the results that week. Go figure!

Holy yuck, batman! LOL!

Beth-- I have the same problem! I've been on a pump a little over 12 years (I use a minimed, but mine has a similar thunk-like insertion as the animas one- I've used those too). One thing that helps me is to make sure my fingers are positioned into the best position to trigger the thunk-- so that I am not squeezing the inserter forever and getting nervous. I count to three to prepare myself before I squeeze. You could also consider trying a silhouette site that you insert manually!

Hmmm. Maybe ticks can be taught to transmit CGM data? Tricky task but tantalizing thought...

(This comment brought to you by the letter T!)

Do you think that the results were so close "Spot On" correct - due to the fact it was in more direct contact with your blood stream? ie- it was bleeding. Maybe?

at least you didn't say "clotted and moist."

@beth - My 5 year old daughter uses the Accu-Chek Tenders infusion sets with her Animas Ping pump. No springs - You just push it in. We used the spring loaded ones for the first year or two but when an endo recommended the Tenders, site changing got a lot easier. Check it out!

Looking forward to seeing you speak this weekend in NashVegas!!!

We have had the New Dexcom for about a month now for my twelve year old. Love love love it!!! Gives me peace of mind and the ability to sleep at night, :-)!!

We have been within 10-20 points between our Omnipod and the Dexcom since we started. Should be handed out to all parents of newly diagnosed children.

Same question...have been using the Dexcom G4 for a week. The tutorial says to only place the sensors on the abdomen. So...anyone know the reason if arm seems to work as well if not better?

I'm also curious about the site placement. I thought the transmitter could only be placed in the abdomen? Have been using a one touch ping for about 9 years and just started using the seven plus again. Where is best results and/or least painful on the thighs or arms?

Excellent grost! :) Funny how pictures like this will gross some people out but then if youre a PWD or a DParent...they're just....fascinating! Haha! We just started the G4 system this week and LOVE it so far! It's been amazingly accurate when testing with her Ping. We've never used any other spot...the back of her arms is the only place she will put her Dexcom. She saves her belly and hips for pump sites. She's never done leg sites. The G4 has been within 10 points every test unless shes double arrows down or double arrows up and even then, it hasn't been off more than 30 points. Keep those grosts coming! ;)

thank you for suggestions Alyssa and Larry.... and its good to know am not the only one!

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