# Running cost of minimed 640G sensors



## SB2015 (Jul 25, 2018)

The new Minimed closed loop system sounds amazing and I am wondering what the cost of the sensors is if you have to self fund, compared with Libre.  Also the number of days they last.  I am not sure whether this is what @everydayupsanddowns  uses?


----------



## everydayupsanddowns (Jul 26, 2018)

Yes it is. 

Officially the sensors only last 6 days, but they can easily be restarted. I almost always get 11-12 days from a sensor before it begins to fail. My longest was 21 days. As soon as calibrations begin to wobble or readings drift I stop them as the predictive low glucose suspend needs good data. 

The cost is almost identical to Libre - you can get 14% off the list price with a new purchasing scheme for occasional self-funders so in my head the sensors are very similar - 12 days vs 14. 

The major extra cost is the transmitter which is approx £500 and is guaranteed for 12 months. Mine is happily still plugging away after 18 months, and I gather from long-term users that up to 3-5 years is not uncommon. 

The major benefit for me over Libre is the major reduction in time spent below 4.0 when I am using them. Libre is great for me and I get a big drop in ‘below 4s’ - but I lose around 90% of the remaining  hypos with Smartguard and have few if any readings below 3.5 per month.


----------



## m1dnc (Jul 27, 2018)

I can echo Mike's comments. I usually get 12 days out of each sensor and my transmitter is still going strong after two years. Inserting the sensor and applying the tape to hold it in place is a bit more fiddly than the Libre, but that's more than off-set by the smartguard feature to head-off hypos. Like Mike I rarely go much below 3.5 now and my last Hba1c was 46.


----------



## SB2015 (Jul 27, 2018)

Thanks m1dnc. I managed a 44 with my Combo and the Libre, but good to hear about the impact  Of the sensors and pump on your control.  Lots to think about.


----------



## Flower (Jul 27, 2018)

Both my transmitters have lasted approx 3.5 years of constant use. I  extend the sensor life whenever possible by up to 6+6 days. and often find the readings even more accurate for the second 6 days or however long I get. 

You do need to remove and recharge the transmitter after 6 days when the sensor expires but with taping in the right place you can remove the transmitter without dislodging thr sensor.


----------



## SB2015 (Jul 28, 2018)

Thanks for all the information @Flower , @everydayupsanddowns and @m1dnc .

Am I right that you can still get the pumps on NHS, and then choose to use sensors with the transmitter instead of the cannulas that would usually be provided?

Where people have done their own techy version, is it the transmitter that they are replacing?


----------



## everydayupsanddowns (Jul 28, 2018)

SB2015 said:


> Thanks for all the information @Flower , @everydayupsanddowns and @m1dnc .
> 
> Am I right that you can still get the pumps on NHS, and then choose to use sensors with the transmitter instead of the cannulas that would usually be provided?



Cannulas and reservoirs are a separate thing. You can happily use the pump just as a pump and never use the integrated sensor parts of it - most people adults using sensors with MM640G are self-funding them as the sensors/transmitter are so rarely funded by the NHS. This is what I do. I order my supplies online and the reservoirs/cannulas are billed to my hospital, but I can separately order the sensors and pay for them myself. 



> Where people have done their own techy version, is it the transmitter that they are replacing?



If you mean Loop, Open APS or xDrip/Nightscout etc - my understanding is that again sensors are mostly self funded. Some people use out-of-warranty pumps for looping. I’m not quite sure *how* they get their reservoirs/cannulas funded!


----------



## grainger (Jul 29, 2018)

Sorry to jump on this thread but was just wondering - I had real issues with sets when I first started pumping and now use the metal sure-t sets... I’ve worn a CGM years ago for 2 weeks without issue, do you think I’d have issues with a sensor? 

What are the major pros and cons? I’m thinking the hypo alert would be amazing but I’m actually more interested in it helping me to reduce highs - do you think this is realistic?

Thanks in advance.


----------



## m1dnc (Jul 29, 2018)

grainger said:


> Sorry to jump on this thread but was just wondering - I had real issues with sets when I first started pumping and now use the metal sure-t sets... I’ve worn a CGM years ago for 2 weeks without issue, do you think I’d have issues with a sensor?
> 
> What are the major pros and cons? I’m thinking the hypo alert would be amazing but I’m actually more interested in it helping me to reduce highs - do you think this is realistic?
> 
> Thanks in advance.


I don't think it matters what sets you are using as far as the CGM is concerned. As Mike said, they are separate functions of the 640G.

The Smartguard feature is more than just a hypo alert. It suspends your basal infusion if it detects that you are heading for a hypo and then restarts the basal when your BG starts to rise again. In my case, I have turned off the alarm because I find that the 640G is rather too keen to raise the alarm at every opportunity (crying wolf syndrome?). But it's great to head off nighttime hypos - the worst for me.

I have found that it has also helped my control; particularly coupled with the Carelink software. It's very effective for tweaking your basal. I have used it with great effect to give an almost flat line BG overnight.

As to cons. Obviously the cost is the major one. As I posted earlier, inserting the sensor and taping it in place is more fiddly than other CGM systems, but it's not a deal breaker. Occasionally I get a bit of irritation under the adhesive, but again it's not enough to worry me.
You have to calibrate the sensor at least twice a day with a fingerstick, but that's not a problem as the sensor is not deemed accurate enough for bolus decisions so you have to do fingersticks at meal times anyway, and you cannot rely on it for driving safety.

I understand that the new Dexcom G6 is much more accurate - to the extent that you can use it's readings for bolus decisions - and it doesn't need calibration in use. I don't think it's been approved yet for driving, and I don't know the extent to which it can be integrated with third party pumps for the equivalent of Smartrguard. It also has a fixed 10-day sensor life and cannot be revived (although I guess someone will figure a workaround for that) so works out a bit more expensive.


----------



## grainger (Jul 29, 2018)

m1dnc said:


> I don't think it matters what sets you are using as far as the CGM is concerned. As Mike said, they are separate functions of the 640G.
> 
> The Smartguard feature is more than just a hypo alert. It suspends your basal infusion if it detects that you are heading for a hypo and then restarts the basal when your BG starts to rise again. In my case, I have turned off the alarm because I find that the 640G is rather too keen to raise the alarm at every opportunity (crying wolf syndrome?). But it's great to head off nighttime hypos - the worst for me.
> 
> ...



Sorry re sets I didn’t mean if they were compatible etc I understand the different functions - it was more of a sensor would be compatible with me given how sets etc weren’t until I used metal ones.


----------



## everydayupsanddowns (Jul 29, 2018)

grainger said:


> Sorry re sets I didn’t mean if they were compatible etc I understand the different functions - it was more of a sensor would be compatible with me given how sets etc weren’t until I used metal ones.



Difficult to be sure without trying them I’m afraid. Not sure what problem you found with the Teflon infusion sets, but if a reaction to adhesive I *think* the adhesive used on Enlites is slightly different. Certainly the Enlite overtapes must use a different adhesive, because I get a rash with them in a way I don’t with anything else!

For highs, I do find CGM very useful. While Smartguard acts silently dodging hypos in the background for me, I have alerts set so that I am warned if my glucose trend looks like I will be above 11mmol/L within 30 minutes. This reduces the alarm nag while also giving me a nudge if I am, say, 9ish and rising so that I can do a quick sense-check of insulin on board and a rethink my last meal estimate/dose strategy to see if I think I need to take action, or just keep an eye on things.


----------



## grainger (Jul 30, 2018)

Problem was with the plastic/Teflon itself... I’ll email my DSN and see what she thinks - just don’t want to spend a fortune initially to discover I can’t use them.

Re the highs - that sounds great. Exactly what I need and should hopefully kick me into gear regarding learning which food spikes (evidently I’m too lazy to do the rigorous testing I should otherwise)

Thanks


----------



## m1dnc (Jul 31, 2018)

grainger said:


> Problem was with the plastic/Teflon itself... I’ll email my DSN and see what she thinks - just don’t want to spend a fortune initially to discover I can’t use them.
> 
> Re the highs - that sounds great. Exactly what I need and should hopefully kick me into gear regarding learning which food spikes (evidently I’m too lazy to do the rigorous testing I should otherwise)
> 
> Thanks


I think that the sensor strip itself - the bit that's inserted - is a complex biosensor/enzyme material coated onto a noble metal (gold?) strip maybe with a polymer coating as well. Why not give the tech support team at Medtronic a call to discuss with them? I have found them to be very helpful. I'd be interested to hear their advice as occasionally I have had some irritation but I've always put that down to the adhesive rather than the sensor strip.


----------



## HOBIE (Jul 31, 2018)

A good Pump & Sensor system


----------



## SB2015 (Aug 1, 2018)

grainger said:


> Sorry to jump on this thread but was just wondering - I had real issues with sets when I first started pumping and now use the metal sure-t sets... I’ve worn a CGM years ago for 2 weeks without issue, do you think I’d have issues with a sensor?
> 
> What are the major pros and cons? I’m thinking the hypo alert would be amazing but I’m actually more interested in it helping me to reduce highs - do you think this is realistic?
> 
> Thanks in advance.


No problem Grainger, glad of your input and interested to hear what you decide.  What are you using at present? I am musing and planning ahead before my next pump change is due.

I was about to ask about sensors myself.  I wonder whether they would let us have ineto out in just to see about sensitivity to them.  I shall phone to find out, as like you I have had a few skanky cannulas and will not want to replace one early.  I have never had a problem with the Libre sensors but they are no metal, so I need to check as I did find the Accu Check Rapid Ds a problem.


----------



## SB2015 (Aug 2, 2018)

grainger said:


> Problem was with the plastic/Teflon itself... I’ll email my DSN and see what she thinks - just don’t want to spend a fortune initially to discover I can’t use them.
> 
> Re the highs - that sounds great. Exactly what I need and should hopefully kick me into gear regarding learning which food spikes (evidently I’m too lazy to do the rigorous testing I should otherwise)
> 
> Thanks


I am on an  enforced rest as I have been poorly so putting my time to good use.  I hope it is of some use to you as well @grainger .

So far ...
I spoke to Medtronic and she is looking into getting me a sensor from the local rep to try, unconnected to a pump just to see if I can tolerate the needle and glue.  I shall see if it can cope with being in for the 12 days that some have suggested that they are able to keep it giong for.  I spoke to my DSN and she is letting me have a try of the Medtronic cannulas.  Then Inshall know whether this is even a possibility for me.

I looked at the you tubes in Medtronic site and was surprised when @everydayupsanddowns popped up in my screen.  Even though I am using a Combo my set change was less bubbly today and I moved my new cannula over just enough to save some tum sites following some of his tips.  Thanks for that Mike.

And now some more questions about the pump, cannulas, sensors and transmitter as I have still not heard from the rep.  In the 640G:
*
Pump and cannulas*
Can you do a suggested bolus, and an adjusted bolus from the handset remotely without having to get your hands on the pump?

Are there Teflon (or equivalent) cannulas at 90 degrees (I know there are the angled ones as Mike demoed putting that in on the video)

Is their technical support line any good when dealing with problems (I have had good service
from Accu Chek over the last few years)

*Sensor and transmitter*
I find that I need to change my cannulas for the Combo almost daily, and I wonder whether any of you users have had issues with the sensor being in for perhaps 12 days? I know that it is only supposed to be 6 days but it is not going to be affordable if I only use each one for 6 days so I am going to be relying on restart.   I tolerate the Libre sensors for 14 days.

Is it feasible to put the sensor transmitter on the back of my upper arm as I do with the Libre or is that too far away?

*Overall use of CGM*
My reason for looking at this system is that I sometimes find it frustrating with all the time D takes up and the space it takes up in my head, and then I generally only stay in target about 70% of the time.  I am hoping that the use of this system would helped it would react to higher BG after incorrect carbs, and it may stop some of the hypos that I have.  The advertising certainly implies that so does it do as it says.

*CGM versus Libre*
This is one for @everydayupsanddowns .  I am aware that you also use the Libre sometimes, and are an intermittent user of CGM.  Is it a case of you choose to use one or the other?  If they work out at about the same cost why would you choose to ever use the Libre instead of CGM?

I am a long way off my next pump but it is good to be prepared.

Phew.  Sorry for the bombardment. Too much time in my hands.


----------



## everydayupsanddowns (Aug 2, 2018)

Hehe @SB2015 - I did some video blogs when I was able to try the MM640G for 64 days in 2015. Hilariously YouTube thinks I have a ‘channel’ though obviously the videos get a bazillion more views when posted on Medtronic’s site than on my little corner of the internet. Glad you found something useful.

For your other questions:

There are choices of 90-degree and angled cannulas (Mios and Mio30s have an inbuilt/disposable inserter, Quicksets and Silhouette have reusable inserters). There are also steel ‘Sure T’.

Teflon cannulas last 3 days. Steel last 2 days. Reservoirs last 3 days.

Tech support and helpline have always been excellent for me. 24 hours and redirected to US helpline seamlessly if UK unavailable for any reason.

Remote bolus. The simple answer is ‘no’. The more complex/tedious answer is that there isn’t a full bolus wizard from the linked BG meter, but you do have 2 options for ‘remote bolus’. One option is to deliver a simple bolus if any amount of units from the meter (you can set a scroll amount as little as 0.1u and then simply click up through the dose and press ‘deliver’. If you want a ‘fancy’ bolus you can preset a square or dual wave (combo or extended) with units, split and duration then choose that from a list of presets. So in theory you could use the remote meter boluses if your ratios were easy, or if your food choices were fairly regular. It’s not a full bolus wizard though.

When I am wearing sensors my results really improve. I lose approx 90% of the lows that I get with my approx ‘70% in range’ Libre results. For the most part I have no audible alerts before low, but if Smartguard can’t quite catch a steeply dipping low I get an alert at 3.9.

I’ve worn sensors on my upper arm just once (the last one I used). I had excellent tracking, no loss of signal or trace and was able to restart twice for 15.5 days. It is a bit tricky to insert/tape down though - I needed an extra person to help.

The only problems I’ve had with Enlites were a slight reaction I had to the supplied overtapes. But I swapped to an alternative dressing I bought online and have had no problems since.

Libre is cheaper and (for me) always lasts the full 14 days. I still occasionally use Libre which (with no alarms) is marginally less intense than a full CGM. But I do miss the overnight protection when wearing Libre not Enlite. I had a run of sensors that only restarted for 1-3 days and that really stung. So part of me likes the stability of 14 day Libre, but the benefits of perhaps an extra 20% time in range with lower hypoglycaemia is a powerful draw to Enlite while my transmitter lasts.


----------



## SB2015 (Aug 2, 2018)

everydayupsanddowns said:


> Hehe @SB2015 - I did some video blogs when I was able to try the MM640G for 64 days in 2015. Hilariously YouTube thinks I have a ‘channel’ though obviously the videos get a bazillion more views when posted on Medtronic’s site than on my little corner of the internet. Glad you found something useful.
> 
> For your other questions:
> 
> ...


Thanks for the detailed response.  Having felt so rough for three weeks now it has been hard work heading off highs and the idea of smartguard is quite appealing.  Sat here with a 15.8 and battling to get it down and to stay down.  I will start that in a different thread for ideas on that.

The Minimed is way ahead but may be worth the switch.  I just have no idea where I would put my pump so that it is readily accessible for boluses, but I would find a way if necessary and soon get used to the necessary change.


----------



## everydayupsanddowns (Aug 3, 2018)

If and when we next meet I will try to remember to show you the remote boluses (very hard to explain) so that you can see if you think you might use them ‘out and about’ and use bolus wizard at home?


----------



## grainger (Aug 3, 2018)

SB2015 said:


> No problem Grainger, glad of your input and interested to hear what you decide.  What are you using at present? I am musing and planning ahead before my next pump change is due.
> 
> I was about to ask about sensors myself.  I wonder whether they would let us have ineto out in just to see about sensitivity to them.  I shall phone to find out, as like you I have had a few skanky cannulas and will not want to replace one early.  I have never had a problem with the Libre sensors but they are no metal, so I need to check as I did find the Accu Check Rapid Ds a problem.



I’m on the 640g pump no sensors. I use steel sure-t cannulas which last me 3 days but at optimum results if I only use for 2.5 days. 
I love the pump and going from mdi to a pump has made my life so much easier even though I had numerous problems in the beginning - just avoided DKA on a couple of occasions with the help of a fab A&E team. Once we found cannulas that I could actually tolerate life became easier - my hba1c is down and whilst isn’t where I want it to be now (I’m blaming my kids and being incredibly lazy when it comes to food) I wouldn’t give my pump back ever!

The sensors for me I’m hoping will be the next step in improved management that helps with my lifestyle too. I’m not organised enough to test every hour to look at food trends etc but I would happily sit down during an evening and review the day and from there be able to make adjustments. Or with the alerts be able to see what’s really going on when I work out/ run/ walk kids to school/ get woken up a hundred times a night/ eat too much kfc etc etc 

I’m going to call Medtronic next week and see what options I have regarding seeing what I can tolerate. Although the cost is a lot I’m v motivated right now to be the healthiest I can be for my kids but know I need to achieve that in a way I’ll actually stick with so I think this’ll be my best option. Also, I’ve had a couple of hypos recently and didn’t feel able to pick up my baby for a good 15-20 mins and I really want something to help me avoid those very rare but real situations.

Sorry rambled a bit there!


----------



## HOBIE (Aug 4, 2018)

Good luck Grainger


----------

