Tag: Dexcom

Day 57 – Loop – Gym and December progress

I am finally starting to return back to normality after starting to pump/Loop. Its taken a few weeks of focusing my efforts on running to gain the experience I wanted to acquire in terms of keeping myself mostly in range while I exercise, so I feel like its time to shift my focus towards cycling and gym again.

Gym (resistance training)

The first gym session back was mostly good, the only issue being Dexcom not registering a pretty severe (2.9 mmol/l) hypo. My body would usually register a hypo way in advance but I was pretty tired from the exercise.

Muscles groups trained: Biceps / Triceps

A gruelling 40 minutes with 5.2 Tons of weight being moved (at least according to Garmin’s calculation from me inputting exercise name and weight), which as expected is less than my last arm session where I moved 5.6 Tons. I’m fairly impressed I did as much as I did, as I was expecting much less.

December blood glucose stats

December 2021 Blood glucose stats are looking better.

My December update is quite pleasing. I am almost at 90% in range (3.9 – 7.8) and I am eating about 30% more carbs than I ate previously to achieve these numbers. I am not sure if I mentioned this before but I did a 30 day muscle building challenge about 3 months ago and one of the difficulties I experienced was eating more calories (to gain muscle) and staying in range. I am very happy with the 5.5% A1C and the standard deviation of 1.4. I would prefer to be 1 or under but with the introduction of more carbs that’s rather difficult to achieve at the moment.

I also wake up in range a lot more frequently these days. I am noticing a few more lows creeping in, perhaps a result of me needing to retune the Loop with the introduction of more frequent exercise?

Recently I feel as though my Dexcom is letting me down. I had two sensors fail back to back, which resulted me being without a CGM for a few days. Also Dexcom seems to be so delayed that by the time it alerts me of a hypo I have already corrected it in most cases. I am using the finger prick calibration method rather than the code calibration, which is supposed to be more accurate. Perhaps I need to adjust my calibration schedule to see if that helps.

Feeling the pump after a long rest period.

Day 52 – Loop – Exercise – Run 11 – Success

Today was a good day! After much trial and more research (through Facebook groups and medical literature) I finally figured out my recipe for staying in my range during cardio. It turns out I may have been too ambitious with my expectations of not eating before some heavy cardio.

The Process I followed was:

  1. Set a temporary over-ride for my basal (40% reduction) and increase my target to 7.

2. I ate a pre-run snack in the form of low carb granola and yogurt.

3. Waited for my glucose to rise above 6 ( I started at 6.8mmol/l)

4. Ran. I kept the loop closed as I wanted to see what would transpire. All in all I think it went well 🙂

Day 42 – Loop – Micro-boluses – Free APS

A few days ago I enabled micro-boluses in Free APS and its been working remarkably well at managing any post prandial blood sugars highs. I have only setup a 45% partial bolus being administered when deemed necessary, but at this stage I feel its performing as I want it to. I still count carbs and administer ‘fake’ or ‘extended’ carbs and simply use the micro-boluses as a tool to quickly administer insulin in place of an extended high temporary basal, which would do the job a little more slowly. Tonight I test this on Chinese food. 🙂

In the chart below we can see that I ate a hearty dinner, and then decided to eat some raisin toast. I managed to stay in range almost the entire evening after all these carbs. Amazing. I would never have even considered doing this before Loop, and if I did I would have anxiety the entire time.

UPDATE: The night went well and overall I am very happy with the results. If I am honest though, I think my expectation in the beginning of this experiment was that Loop would autonomously manage my blood sugar with very little input from myself, but I have realised and this is not the case, and adapted my management to include pre-emptive blood sugar correction. I am certain that Loop would indeed make these decisions, but keeping my finger on the pulse allows me to obtain the level of blood sugar control I am after.

Time-in-range (TIR) = >3.9 AND < 7.8mmol/l

The goal: Eat Chinese food and stay in range

The strategy: I went onto MyFitnessPal and found honey chicken, pork pieces and mixed veg. I added them into the dinner section and calculated the insulin required for the carbohydrate, protein and fat macros. I was not sold on the bolus amount for the carbs and ended up only injecting 70% of the calculated amount, but Loop quickly started administering micro-boluses to correct this. The ‘fake carbs’ ( I don’t really know why this name has gained so much traction in the diabetic community, since proteins and fats end up being synthesised into glucose (carbs) through gluconeogenesis, and are thus sugars (real carbs) being generated by the body at a slower rate than the exogenous carbs we eat) for protein and fat were then added to Loop with a 4.5 hour digestion period. This will allow Loop to attribute blood sugar changes to carbs (from gluconeogenesis) for up to 6 hours, and be able to micro-bolus or increase basal for them.

The outcome: I noticed that after an hour I had a substantial amount of insulin on-board and my blood glucose (BG) was dropping at a rate that could not be sustained by the food I had eaten, so I ate another 20g of faster acting carbs. An hour after that I had a mild hypo (3.7 mmol/l) and ended up eating again to correct this. I believe a better strategy may have been to inject 60% of the bolus up-front and then monitor for an hour before injecting the remaining bolus. Then again, this may have been just a carb-counting error on my part.

Day 41 – Loop progress

I have now been Looping for 41 days and I wanted to reflect on the reasons I started looping and the goals I wanted to achieve while Looping.

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  • A1C of below 5.5%
  • Time-in-Range exceeding 80% (3.9mmol/l -7.8 mmol/l)
  • Reduce diabetic burden
  • Decrease food anxiety whilst increasing food options.
  • Improved time-in-range during exercise with decreased exercise anxiety

    • Lets start with A1C and Time-in-Range (TIR)

    If we look at my stats just prior to looping, I had an A1C of 5.6% and a time-in-range (TIR) of 78.5%. The GVI and PGS stats were also really decent (more on these metrics here https://bionicwookiee.com/2020/02/26/cgm-metrics-gvi-pgs/), with a GVI of 1.2 (non-diabetic) and a PGS of 29 (non-diabetic). A decent average of 6.4 mmol/l, and 3.4 % (1h4min) of time in the 3.0 mmol/l – 3.9 mmol/l range.

    Now we look at my last month while on Loop. In order to reflect the learning curve involved from switching to a pump, I broke the stats into two (2) fortnightly blocks.

    First two (2) weeks on Loop
    Last two (2) weeks on Loop

    As can be seen in the charts above, some slight improvements are seen in all metrics discussed above with a 7.6% reduction in TIR and a 4.5% (-0.3) reduction in average blood glucose. The GVI and PGS metrics reflect modest variability and good control, as opposed to the previous non-diabetic results. I spent 22min (2%) in the 3-3.9 mmol/l range, down 10min from the previous periods 32min.

    Reduce diabetic burden

    This goal is subjective and difficult to quantify. Loop does make it easy to administer insulin, enable an over-ride, track carbohydrate absorption ( I was doing this with Spike) correct a hypo/hyper and even just wake up in-range. It does come with its own challenges and hurdles to overcome, like ensuring you have an up-to-date version, checking certificate expiry, ensuring your CGM is calibrated accurately, and then the challenges of constant site changes, reservoir and battery changes, insulin mixing and exercise.

    Decrease food anxiety while increasing food options

    It definitely feels like less of a burden to experiment with food or eat more carbs, as Loop can pick up any slack due to incorrect bolus calculations, or adjustments after exercise. I used to have 3.4 % (1h4min) hypos (3.0 mmol/l – 3.9 mmol/l) in a month due to incorrect dosing after exercise, but this number has significantly reduced to 2% (22min) while using Loop, as basal can be dynamically adjusted to fluctuations in blood glucose. Post prandial (meal) hyperglycaemia has also significantly been reduced, but I think in part due to Fiasp as it starts working immediately once injected.

    MDI Average Carbs per day: 92.6 (*excluding ‘fake carbs’)

    Loop Average Carbs per day: 121 (*including ‘fake carbs’)

    *’Fake carbs’ are entered into Loop to manage the blood sugar spikes from gluconeogenesis (fat/protein synthesis into glucose)

    Improve time-in-range (TIR) during exercise with decreased exercise anxiety

    Unfortunately since switching to Loop the Python code I wrote to analyse blood glucose broke with the switch to Loop, so I only have the pre-loop analysis. I was quite happy with the control I had during exercise while on MDI.

    I have included the table I have been updating while I work on the Python code, which doesn’t seem to accurately reflect the amount of hypo events I have experienced while running. On the whole cardio has been the item on my list I have struggled with the most, and has been a significant source of anxiety. I am quite certain that after a few months I will have a strategy nailed down and the anxiety associated with exercise will wane. As can be seen in the below table, I am currently focusing on running as its the exercise I am struggling to gain control over the most. I was able to stay in range for the entire duration of all my weight sessions.

    I’ll write a follow up post in the next month before I start my Android APS experiment. Good luck fellow Loopers!!

    Day 36 – Loop – Exercise – Run

    An interesting development from moving over to a pump has been exercise. Whilst resistance training hasn’t resulted in any issues controlling blood glucose (BG), aerobic (cardio) training seems to be heavily impacted by the fast acting insulin being used as basal. My previous strategy was to have no insulin on board (IOB) and fasted, this approach doesn’t work as well when pumping. My ability to stay in range during runs are improving by including fast acting carbs (preferably in liquid form) prior to running, but there is still much tuning to be done. My strategy yesterday was ingesting about 25g of carbs before the run and injecting .3 units just prior to running. I wanted to try this because it was raining and I wanted to disconnect the pump when I ran, as apposed to how I was managing it by reducing basal (50%) 30 min prior to running and for the duration of the run. It was a terrible idea!

    I ended up having a little low during the run and then rebounding from adrenaline ( I had a little race with my running partner) from sprinting. This resulted in me needing to wait an extra hour to bring my glucose back into range before lunch.

    Time in Range was calculated at <3.9 mmol/l AND >7.8 mmol/l

    The daily stats are definitely improving as can be seen by my time in range (TIR) stats above. The morning basal testing revealed that I needed to increase by basal from about 6am up from .8 U/hour to at least 1.1. U/hour, further testing is still required in order to confirm these numbers. I had around 100g of carbs, including ‘fake carbs’ which is added into Loop as 25% of protein and 10% of fat per meal. I’m still not convinced that Loop is particularly effective at managing gluconeogenesis (the conversation of protein and fat into carbohydrates) as I find that if I use 4 hour digestion times I go low and 5 hour digestion times I spike slightly. I suppose more testing in needed 🙂

    15 days into starting my Anubis transmitter with Dexcom sensor and so far its working fairly well. I’m interested to see how these sensors hold up on other parts of the body in comparison.

    Day 26

    Day 26 of this adventure… Its cannula and reservoir change day. I’m slowly getting the hang of it now.
    Day 5 of the Dexcom experiment. So far I am not sold. I certainly don’t feel its more accurate than the Libre + miao miao combo (especially with spike as the collector). Once a Libre was calibrated correctly I felt pretty comfortable that I wasn’t having a hypo but the Dexcom was telling me I was a stable 5.6 mmol/l.
    I am keen to analyse the accuracy between the two methods. Let the data collection begin.