Dexcom Sensor insertion after anesthetic

Hi, I’ve been using Dexcom G6 since November. I’ve had T1 for nearly 40 years and this has made a massive difference - I love it! Until last night I had only had one sensor failure. I had a small procedure yesterday morning under general anaesthetic and this day coincided with my sensor change in the evening. 3 failed, I went to bed and a 4th failed this morning. Rang Dexcom and yes, they are going to replace the 4 sensors which is great. But they asked me if I had taken Acetaminophen as if it might interfere with sensor insertion success. I don’t think the drug used for anaesthesia does contain Acetaminophen but I wondered if anyone had experienced sensor failure after anaesthesia?

Hi Lorna @LornaHadman, really sorry to hear about your sensor failures just at the time when they are most needed.

I do not use the G6, but rather the G5 and I did NOT incur any failures last month on two different days when I had procedures performed while I was under full anesthesia. I did make it clear before the procedures that, if possible, I wanted to avoid Acetaminophen before, during and after.

I do hope that you are now on your way to recovery.

Hi Dennis Thank you for your message. Dexcom tech support could not figure out why the sensors had failed 4 times but I have now. I was on a call to Sales and asked what is probably a question for the tech team, “do you just pull off the old transmitter and replace at end of its 30 days even if you are in the middle of a 10 day sensor period?” She told me yes you do, but if you are replacing your sensor and your transmitter has less than 10 days left on it, sensors will fail each time. Bingo - that was why they all failed last night! I so wish I’d been told that when I started. For a few days at least, I’m back to the dinosaur days of finger prick tests!

Lorna @LornaHadman, my G5 transmitters are supposed to last for at least 90 days and as I approach the expiration, I look ahead in my devices to make certain there is sufficient battery life left.
Just last week when I was replacing my 7-day sensor period, my receiver told me to also replace the transmitter. I was really happy to get that notification.

Anesthesia in and of itself should not interfere with your G6, but depending upon what type of surgery you had, you could certainly have received acetaminophen, even without knowing, as there is an IV form. That said, acetaminophen would cause erroneous readings, not typically sensor failure. I would bet this is a bad (or near expiration) transmitter.

Thank you Cindy yes, you are right, I have since discovered by accident that the sensors failed because I had less than 10 days left on them. Nobody had told me this, perhaps Dexcom think this is obvious? Anyway, I’m new to CGM and to this fantastic forum and learning new info all the time. Knew about steriods causing insulin resistance but not about effect of Acetaminophen on sensor readings, so I’ll watch out for that now too.

REALLY disappointed to hear that G6 transmitters are rated for only 30 days. Thought that G5 at 90 days was awful. My G4 transmitter is now on day 300. Guess I’ll stick with G4 as long as I can to avoid hundreds of $$ in extra co-pays.

@jjmnav, according to the DexCom website, the G6 transmitter lasts at least 3 Months.

What do you do to make your G4 last so long? I’ve had a G5 last 114 days.

I just use it - the longest lasting was a bit over a year, the shortest was a bit over 7 months. Bluetooth makes sharing easy but at the cost of shorter battery life.

We use the G6 and it’s supposed to not have the acetaminophen interference like the G5 does. We did go through a WHOLE BOX of sensors this weekend when we had some insertion/startup failures. I’m not sure if it has anything to do with the issues you’re seeing, but I did learn something I’d like to share. When starting up, I changed the sensor too fast and tried to start up again. Despite the new code, the Dexcom app thought I was trying to restart an old sensor and gave me an error saying to change the (new) sensor. Dexcom Technical Support told me (after the second failed startup) that you have to wait 10-15 minutes after your session end or you stop the sensor to start up a new sensor or it can get confused and think you’re trying to restart the old one. It was incredibly frustrating and they are going to warranty my two sensors that failed to start up, but man… that was tough. 3 sensor insertions in less than 12 hours!

Just FYI, that waiting 15 minutes after you try to start a new sensor is also a way to reuse sensor a 2nd time. Just hit start new sensor and then hit no code, wait 15 min then hit stop sensor. Hit start again and enter old code this time. Works like a charm for me.