Posted by on Tuesday 8 May 2012

Face-off: MDI vs Pump

If you've not seen this film before, you should! Face/Off [DVD] [1997]
A couple of people who are considering going on an insulin pump were asking how I was getting on, how I was finding it and whether I thought it had made any difference.

An interesting question a little over 6 months into the experience.

Pump win(?): Fear of attachment
The first thing to say is that the nagging worries I still had about attachment when I wrote a few weeks after starting on a pump have long gone. I know some people feel at one with their robot pancreas almost immediately, but it took me a good few months before I reached the stage where I rarely thought about being hooked up to Artoo, and even when I did, it didn't worry me. Things like getting changed, where the sense of inconvenience lingered, no longer strike me as irritating. If you have just started on a pump, and the attachment still frustrates you, hang in there. Not everyone gets used to it in a few days. Allow yourself time to adapt to the new 'normal'. Wearing and using Artoo is now second nature. No problem with sleeping either.

Hugely unexpected pump win: Attachment
I think this bears repeating from my '2 month' post, partly because it was something I really didn't see coming. There have been many times since starting on a pump that being attached to Artoo 24/7 has given me back a feeling of spontaneity. Do you remember spontaneity? I'd pretty much forgotten about it myself too. That ability to just stop and have lunch there because you fancy it, rather than having to go back home because you weren't expecting to be out that long and didn't bring your kit. There have also been *no* times since November when we've had to stop the car at the end of the street, and run back to fetch my pencil case.

Pump win: Basal patterns
A properly flexible basal pattern was one of my main motivations to switch to a pump. Looking back, while on MDI my early morning 'fasting' reading of the day was more erratic than I realised at the time. Sometimes too high, sometimes too low. Only in a decent range say, between 3.9mmol/L (70mg/dl) and 7.5 (135), less than half the time (45% to be exact). Truth be known it's still wobblier than I'd like, but these days I get a decent first reading on two out of three days. That's a much cheerier start to the day for everyone at the breakfast table.

Pump win: Delivery options
I was invited to an evening arranged by Medtronic in March where pumps and pump therapy were discussed. It surprised me how many people had been on a pump for years but had never tried out different bolus patterns or temporary basal rates. If you are new to a pump I'd encourage you to get stuck in straight away. TBRs, dual and square wave boluses have more than lived up to my expectations. Many situations, like gardening and vacuuming which refused to play nicely for me on MDI have been more or less tamed by Artoo. I don't get it right all the time, but have a little 'cheat sheet' of notes for what seemed to work before to use as a basis for whatever I'm doing and I have avoided many many spikes and/or hypos since November.

MDI win: Infusion site failures
On the plus side set changes have become much easier and more automatic. They are a little more time consuming than a simple injection, but you do know roughly when they are due and can bring that forward/push that back slightly if it would come at an inconvenient time. The whole push-button dosing thing is so much quicker and easier than faffing about with a pen that my feeling is that I have a net gain of time spent/inconvenience endured dealing with diabetic rigmarole.

But. (and it's a biggie)...

I have had sites go wrong already. I still watch every set change carefully to make sure they have 'taken' properly. I had almost stopped being so paranoid, but two or three failures in quick succession have put me on my guard again. At least two cannulas have kinked on or after insertion so that insulin wasn't being infused properly. Not serious enough to get a 'low delivery' warning, but enough to cause a rise in BG levels. I had another site seemed to 'go off' at about 1.5 days. It had been fine, but suddenly stopped working as expected. I am putting these down to site issues because corrections did not behave properly, but as soon as the site was changed I was back on an even keel. I've also caught a big fat bubble in the tubing on at least two occasions when I've put Artoo back on after a shower/gym session - which makes me wonder if some odd but short lived rises in BG might be down to Artoo delivering 'bubble' rather than basal for an hour or two on other days. I check carefully every time I fill a reservoir and flick and fiddle until I am as sure as I can be that I have got all the bubbles out, but nevertheless I can still sometimes see a bubble in the reservoir at the next set change. These are not problems that you ever have with MDI. Even if you hit a dodgy site that is only going to be one out of the day's several injections. With Artoo all my eggs are in one basket. And sometimes the handle falls off the basket. I have had one-off levels on a pump higher than I've had for years on MDI, perhaps the highest since I was first diagnosed. And I've also tested positive for ketones since November - again not something I am used to. In all I've probably had to swap out maybe six sites since November. As a percentage of the total number of insertions it's not disastrous. but it's not ideal either.

MDI win: Injection site availability
Another part of this is the available site locations. I was never very adventurous on MDI, but I had far more area to play with in terms of a quick injection than is suitable to have something fixed to it for several days. I'm currently using sides and back for sites to give my abdomen a rest but have to be careful to find a spot with enough 'flesh' and some places end up being slightly uncomfortable when you lean on them/sit on them/risk getting them knocked out by waistband. In theory I could use my thighs, but there's not a lot of 'spare covering' there and most of the usable area seems to be right underneath my jeans pockets which I'm forever fishing stuff out of. I worry I'd just pull the site out when trying to get hold of my my keys.

But what of the results so far?
It's never very easy for me to spot how things are going from day to day. A couple of good (or bad) days on the trot and it can feel like I'm some sort of perpetual Diabetes Superhero/Catastrophe. Sometimes it feels like I've been having a problem for months, but looking back just a week or two and it becomes clear that it has only been a matter of days.

So I dug back through my records and picked some results to compare from three periods. Some old paper records from around the time we started writing this blog, some records towards the end of my time with the Accu-Chek Expert and some more recent ones with Artoo. I pulled 60 days of results to try to reduce the impact of a dodgy few weeks. I avoided holidays/Christmas or other challenging times of year and tried to pick a couple of 'normal' months for each. I knew things have been getting better for me in recent years, but I've not really compared and contrasted in this way before.

Testing frequency was roughly even in each case (between 7 and 8 times a day) and are made up of a mixture of waking, pre meal, post meal and bedtime tests.

The first thing that surprised me was how much improvement I had been able to make on my own with MDI, even before the help of the Expert. Due to an, ahem, administrative/back-up error I don't have a full 60 days immediately pre-Expert to compare, but even so, before Artoo the number of highs and lows were substantially improved.

Hypos - below 3.9 (70)
Old MDI was the worst with 20% of readings, the Expert reduced this to 10% of readings and Artoo has made a small improvement taking this down to 8.7% - clearly Artoo and I still have work to do here.

Hypos - below 3 (54)
The old MDI records really don't do well here, with almost half of all hypos coming in below the 3 (54) mark. Compared to what I'm used to in recent years it made uncomfortable viewing. Both the Expert and Artoo fare much better with 2.4% and 2% of all readings coming in at that level. Both with the Expert and with Artoo, none of these hypos have been 'nasties'. I can't remember the last time I had a really bad one it was so many years ago. I've been functioning, spotted them and able to treat them all myself. That may not have been the case with the old MDI records.

Highs - above 10 (180)
The same pattern of worse, slightly better, better again repeats here. Old MDI shows 19% of readings over 10, with the Expert that falls to 16% and reduces to 13% with Artoos assistance.

Highs - above 13 (234)
This is where Artoo really shines at the moment. Despite having subjected me to an occasional stratospheric BG with a dodgy set, in the 60 days of data Artoo only allowed 0.04% of readings to stray over 13. The Expert does surprisingly badly here with 6% while even old chaotic-style MDI scrapes in with 5%.

Averages and SD
While averages can hide a multitude of unpleasant detail, I think that here they do seem to suggest positive progression. The old MDI average was 6.8 (122) with an SD of 3.3 (59), the Expert improves this with a slightly higher average 7.2 (130) but reduced SD of 3.0 (54). Artoo though trumps them all with the joint lowest average 6.8 (122) and a significantly lower SD of 2.4 (43).

So is it worth it?
YES! Absolutely. The ways in which Artoo has made my diabetic life easier to control, more spontaneous and simpler to get along with far outweigh the remaining niggles I have about infusion sites. Is it like being non-diabetic? No of course not. Actually I have to watch myself not to feel downhearted if I don't have perfect levels all the time because some mad part of my brain thinks that in theory this ought to be possible now. Well unfortunately Diabetes is still incredibly annoying and has lost none of its ability to throw out the rulebook and move the goalposts for weeks at a time. I don't suppose it ever will.

I have an HbA1c coming up in the next few months. It will be interesting to see if there is an improvement - my first post-pump A1c showed an 0.5% increase and I'm hoping I might be able to match my previous MDI result but with fewer highs and lows into the bargain.

We shall see.

UPDATE: Regarding set failures - I wrote this some months later. Set changes


  1. As we are only on our third week of pumping this made interesting reading. Jack and I agree with much of what you said - we have already tried experimenting with the extended bolus and multiwave and with a bit of tweaking I can see this being a real advantage. The lack of fleshy sites can be a problem and I think that he has definitely had a few that haven't worked as well. As someone who was regularly in double figures only two BGs of over 14 in 3 weeks has been a revelation - and an adjustment on the first week's basal has reduced the hypos he was getting after starting with the pump. But I completely agree with you that if anything the pump highlights even more what a fickle beast T1 is - highs and lows sometimes happen for no obvious reason and just as you are trying to work out a pattern things go back to 'normal' again for a while - exasperating!

  2. Thanks Louisa. Sounds like you are getting on brilliantly. Look forward to reading more of your experiences in the coming weeks. :)

  3. i'm happy that you're happy with your decision to try the pump! glad you're getting used to artoo.

    bad sites are frustrating. we all hit bad spots. i recently switched to sure-ts, which has taken away the worry about kinked cannulas. the steel cannula can't kink. though i still get bad spots. i don't think anything can get rid of that.

    also, i like to use my arms for set sites. and i don't use my legs either. :)

  4. I have only been in the pump for about 5 weeks and I have to admit I hated the idea of having felt like I had failed with MDI and in keeping HbA1c'at a good level. My pump is now part of me I don't mind sticking it on the waistband of my skirt or jeans (the legs strap takes some getting used to) ladies if like me you like to wear dresses working out where the pump can live for the day is fun(!) I have had a few kinks and they have brought my BG sky high but I feel like I'm starting to love my pump. It is a symbol of a part of me but that's not all I am and I'm proud that medicine has come so far the something the size of a beeper can keep me going for 3 days. Thanks Viv