I live in MA which is going to be suffering through a “heat dome” over the next few days with temps of 96 degrees and heat indexes of 106 degrees. Of course, my Dexcom sensors (which have already been shipped) are due to arrive tomorrow, at the height of the heat wave. I may or may not be home to bring them right inside, but either way, my concern is that the sensors will be toast on arrival after baking on the hot UPS truck all day. I called UPS to ask if they can hold the package at their nearest facility so I can pick them up, but they said that wasn’t possible for this package and told me to contact the sender (CCS Medical). I contacted CCS Medical and they told me there was nothing they could do either since the package has already left their hands. So I’m basically SOL, since the sensors aren’t supposed to be kept over a certain temperature and it should be a nice balmy 120 degrees inside the UPS truck tomorrow. Dexcom hasn’t responded to my inquiry yet about what to do—but I’m concerned about using potentially unreliable sensors that may be damaged from heat through no fault of my own. Have any of you ever dealt with this before? Did Dexcom proactively replace sensors that arrived during an extreme heat wave?
I live in Texas and your forecasted temperatures are just SOP from May through September. I have never had an issue with the sensors not working when exposed to the heat in the UPS unairconditioned van or on the porch in the afternoon Texas sun.
I don’t think that kind of temperature can damage the reagent on the sensor. I would be more concerned about the adhesive being damaged, but I suspect that would take more than a few days.
I wouldn’t worry about that. The sensors are exposed to 98.6 degrees when you are wearing them!
I understand your concern, but I wouldn’t worry about it too much. The temperature outdoors is only slightly higher than the recommendation, and I imagine that you can call and get a new batch from your supplier or Dexcom, just make sure you keep all of your packaging and emails.
From Dexcom
Storing your sensors:
Keep in its sterile packaging until you’re ready to use it.
Store at temperatures between 36°F and 86°F.
Storing outside this range may cause inaccurate G6 readings.
You may store sensor in refrigerator if it’s within temperature range.
Store sensors in a cool, dry place. Don’t store in parked car on a hot day or in freezer.
Link:
https://www.dexcom.com/faqs/how-do-i-store-my-dexcom-supplies
Temp:
Ya, I live in MA, too, and those temps are pretty balmy compared to my office in Delhi and other parts of the world that are at 109 degrees right now. I have never had any temperature issues with sensors/transmitters, but once during the Summer, I lost a load of insulin; UPS put it on my doorstep, facing directly into the Sun, and sat there for a week baking while I was overseas. Insulin is the only diabetes related item I have ever lost due to heat.
Gotta remember that recommendations from the manufacturer just indicate what their testing conditions were. It does not actually mean the product self-combusts outside that range, only that the sensors weren’t tested for accuracy at any other storage temperature.
There is an enzyme on the sensors, glucose oxidase, which could definitely be damaged by extreme temps. Low 100s isn’t extreme, though. Glucose oxidase is stable all the way to 76°C/168°F, possibly higher. So I wouldn’t sweat it, personally.
The same rule apply as always. Fingerstick if you don’t trust the CGM and/or if your symptoms don’t match the data. If it’s inaccurate, Dexcom will replace it. Don’t provide any more info than they ask for.
@hollymateluber’s concern is valid and I agree that the UPS warehouse and truck are going to be hotter than a snakes butt in a wheel rut. I hope she posts Dexcom’s response.
I will share in my personal experience like others here I live where 90 is a lovely spring day and I don’t give two thoughts to leaving my dexcom delivery on the porch all day till I get home. I have been out in the 110s and the G6 did stop giving readings. I can’t remember the error if any. The manual says the transmitter operational range 50°F–107.6°F. My wild guess is the 86° is about the pressure sensitive adhesive.
While your concern is valid, most people forget that the heat index is not the same as the temperature. The heat index is like the wind chill, and is what the humidity makes the temperature feel, but is it has nothing to do with the temperature. It might feel like 120 degrees but a thermometer will read high 90’s. Humidity has a weird effect on the skin and will make things feel hotter or colder than the actual temperature.
I live in Arizona. Been a nice 111 degrees. I pick up my insulin at my pharmacy. Too nervous for it to be shipped even if packaged correctly.
Here’s the simplest answer: use the sensors you receive, however keep the box of each sensor you use/insert. If a sensor fails in under 10 days, contact Dexcom Tech Support. They’ll want the lot number and other data from the box. They might even ask for the failed sensor to be sent back to them.
If you have not taken loads of acetaminophen, if you put the sensor on properly in an approved location, then they should replace it. Doesn’t matter why it failed, and you shouldn’t presume - as others have pointed out - that heat index in your area is the cause. (Lord knows they replace many of mine because the glue doesn’t hold and they come out, insertion hits a capillary and the bleeding interferes with readings, the readings are consistently off-base even with calibrations.)
If the tech representative insists they won’t replace a failed sensor, you can insist on speaking with a supervisor.
These sensors are not bulletproof, but they are expensive - even with insurance. Hold Dexcom accountable, just as they hold patients accountable for proper insertion, etc. Over 10 years, they have always seemed reasonable (at least to me) to deal with.
Climate change is happening, companies in the science/medicine/technology space know this, and if they need to make improvements to their products to match our changing environment, that is all the more reason to let them know their products fail. It is up to the company to figure out why they fail (heat index or other) and how to make the product reliable.
Does anyone remember that G4 sensors used to ship in cold packs? And then one day they didn’t, without any explanation.
I came looking to The forum to see about other people’s experience with sensors being shipped during heat waves.
I was disappointed by some of the answers because the rationales were not sound.
First ambient temperature matters but that at point of delivery is not a reliable indication of what a sensor has experienced.
The temperature at a surface such as concrete stairs or dark painted wood can be +30°F above ambient if it is indirect sunlight.
I received a shipment from UPS today and brought it inside within 2 minutes of the time that the truck stopped. The box felt unusually warm to me so being a skeptic I check the internal temperature of one of the G6 cartons with an infrared thermometer it was 123°F. The ambient temperature was 92°F. UPS truck drivers may be air conditioned but apparently not the cargo areas.
Second the ability of a chemical to react depends on more than the temperature at which it breaks down. The grain structure, permeability and solubility depend upon the amount of moisture in the compound . In the case of a coated surface how it is fused or attached to that surface also affects reactions.
Safe storage limits are indicated for G6 sensors to assure that more than 95% of sensors will be acceptably accurate, that is how sensors for the clinical trials were handled. There is no data available on how accurate they are if stored above the stated safe storage limit for any given time.
Third, Dexcoms corporate policy as of this year is to replace three G6 sensors per year for free. (Look at Dexcom’s share price for the past year they have good reason to be concerned about expenses.)
In the 3 years since I started using G6s I have never had less than five sensor failures per year. If I were not on Medicare with a Part B supplement I would be more concerned about anything that might cause my sensors to fail.
I can accept that some people who use sensors have found them to be accurate enough for their use
after they were exposed to higher temperatures.
However I know that a very high percentage of people despite using G6 sensors do not achieve the recommended A1C targets and many do not routinely check their sensors for accuracy against finger sticks.
So, being a user of a closed loop pump system and intent on keeping my A1C below 5.5% I can’t accept measurement devices that are good enough most. without question, so I will be giving these 9 sensors extra attention
I pick up my Freestyle Libre 3+ sensors from local Walgreens anybody know what precautions they use?
(I’ll ask next time.)
Check your sensor performance against a manual blood sugar stick.
As you have clearly gone to the trouble of making a spot check of temperature, I would suggest that you go to the next level of data collection.
I. Check out:
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These are small temperature data loggers that will collect up to 10,000 data points at a selectable interval of one minute or greater. At one point every minute, that would be about a week. At 5 minute intervals it is over a month.
Cost: a 10-pack is $46. Note: these are only rated up to 40 C (104 F). I don’t know what they read if they are hotter than that. -
Save Dexcom G6 packaging, inserter, etc and simulate packaging of a shipment, but with one or more of these devices in your box. Note: these devices are close to the size of a G6 or G7 sensor.
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Ship this using the same service your sensors arrive by to someone that lives in a hot area and get them to apply a return label and send it back you you using the same service. That way you get two one-way sets of data.
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Download the data and match it against tracking information to determine it was sitting in a warehouse, traveling in a truck, sitting on a step, etc.
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Figure out for this sample run, how much time during the entire interval was it hotter than body temperature.
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Share this data with Dexcom and/or your sensor supplier. Will they care? Who knows ……
Note: there may be other comparable devices with a wider temperature range.
I have no affiliation with Elitech. I’m just using their devices to collect data for a problematic HVAC system.
Good luck.
John
Those are the freebies. If you submit a report with all the information they require that doesn’t count towards the freebie limit.
Be aware that the online form cannot be submitted unless you get everything correct; if you don’t you will get an “expected error call this number” message and the person you call won’t clarify why. This happened to me today (my Dexcom G7 receiver went into a reboot loop two or three days ago); I didn’t give my weight and the report wouldn’t submit. After talking to Dexcom support and being told my Dexcom receiver was out of warranty (1 year, the receiver was 1 year plus 28 days old when it failed) the very nice lady asked me to complete my profile by telling her what my weight was.
Before or after I called Dexcom support and had to “weight” for an hour?