Split Bolus

[digihat]

Good Afternoon Everyone

I was wondering about split bolus and when you tend to use them?. I use them with the usual suspects pizza and when I have any bread bases products etc.

I often have occasions where the bolus peters out and the delayed rise kicks in such as with jacket and cheese assuming this is down to the fat from the cheese?

One thing I've not been able to get my head around yet which I have seen other people talk about is taking account of the protein fat etc when planning Insulin doses

Was just wondering how you go about planning that in for when to use split bolus?

 

[rebrascora]

Generally speaking, if you eat enough carbs with a meal, you don't need to factor in protein and possibly fat. If the body gets enough carbs from a meal, it doesn't try to break down protein and fat for the glucose it needs. For me on a low carb way of eating, I do have to inject for protein and possibly fat to a much lesser extent, but I don't calculate it, I just keep an eye on my Libre and inject a correction or two for protein when my levels get to 8mmols and continue rising. This is just my way of managing a low carb way of eating with Fiasp as my insulin.

I do wonder about whether high fat meals confuse the body into thinking it is a low carb meal and that it needs to break down protein and fat, because carbs have not released in that first hour or so. That is just a guess on my part but would explain why fattier meals seem to need a lot more insulin than you would expect, several hours after you would expect, often whilst you are sleeping.

Does a split dose with your normal ratio work for the likes of pizza for you or do you find you go high several hours later and perhaps overnight after it, despite injecting what you believe to be the correct dose?

 

[everydayupsanddowns]

The only time I really use a split dose is when the amount of insulin I need, taken all up front, acts too fast for the meal (especially larger meals which take longer to digest, and seem to need a ‘stronger’ ratio for me). Which can mean that I go low or hypo after the meal when the dose is rampant, but then levels rise much later, as you describe.

So splitting the dose allows a ‘spread’ of the insulin action over a longer period.

The splits that seemed to work well for me tended to be around the 60:40 over 2hrs mark. But at different times it was more like 30:70, or 50:50 over 1hr or 1.5hrs.

Very much a case of careful experimentation and keeping notes on what different meals need.

Having shifted to MM780G, I no longer have a dual wave option. The rep just said “take it all up front, and let the pump sort it out” but that caused a BG nosedive Deep Thought couldn’t catch, so I’m back to taking a guesstimated ‘about half the carbs’ and then the rest after 90-120 mins. It’s still a bit of a work in progress!

 

[SimonP]

I always split if I am going to eat more than 60g of carbs, as I try to avoid taking more than 6U at a go in the evening. This is therefore most evenings. If it's a fatty meal, I will lengthen the gap before taking more insulin. I play it by ear looking at the trend line and XDrip+'s approximation of CoB and IoB to give me a steer as to how much more insulin to take. I find that if I let the activity curve (at the bottom of XDrip+ - i.e. how much insulin is active) drop too far I will rise, so I try to give more insulin before this happens (which may be when I have ~2U IoB remaining.) It's very much based on experience though.

 

[digihat]

Generally speaking, if you eat enough carbs with a meal, you don't need to factor in protein and possibly fat. If the body gets enough carbs from a meal, it doesn't try to break down protein and fat for the glucose it needs. For me on a low carb way of eating, I do have to inject for protein and possibly fat to a much lesser extent, but I don't calculate it, I just keep an eye on my Libre and inject a correction or two for protein when my levels get to 8mmols and continue rising. This is just my way of managing a low carb way of eating with Fiasp as my insulin.

I do wonder about whether high fat meals confuse the body into thinking it is a low carb meal and that it needs to break down protein and fat, because carbs have not released in that first hour or so. That is just a guess on my part but would explain why fattier meals seem to need a lot more insulin than you would expect, several hours after you would expect, often whilst you are sleeping.

Does a split dose with your normal ratio work for the likes of pizza for you or do you find you go high several hours later and perhaps overnight after it, despite injecting what you believe to be the correct dose?

My current ratio when doing a split tends to manage to hold the rise but not bring it down. I tend to a 60;40 split with about 2 hours head start for the first part. I don't tend to like having active bolus when asleep if I can avoid it just a personal thing can't always avoid it of course. I've been extending my pre bolus to 25 minutes before meals last few days which has been helping with rises quite a lot so will try it with a split at the weekend 🙂

 

[digihat]

The only time I really use a split dose is when the amount of insulin I need, taken all up front, acts too fast for the meal (especially larger meals which take longer to digest, and seem to need a ‘stronger’ ratio for me). Which can mean that I go low or hypo after the meal when the dose is rampant, but then levels rise much later, as you describe.

So splitting the dose allows a ‘spread’ of the insulin action over a longer period.

The splits that seemed to work well for me tended to be around the 60:40 over 2hrs mark. But at different times it was more like 30:70, or 50:50 over 1hr or 1.5hrs.

Very much a case of careful experimentation and keeping notes on what different meals need.

Having shifted to MM780G, I no longer have a dual wave option. The rep just said “take it all up front, and let the pump sort it out” but that caused a BG nosedive Deep Thought couldn’t catch, so I’m back to taking a guesstimated ‘about half the carbs’ and then the rest after 90-120 mins. It’s still a bit of a work in progress!

Out of interest do lager doses of Insulin kick in faster? Yeah I currently do 60;40 split with a 2 hour split which has sorted of worked at times maybe need to do a bit more even as I find I can halt the rise but then doesn't come down

 

[digihat]

I always split if I am going to eat more than 60g of carbs, as I try to avoid taking more than 6U at a go in the evening. This is therefore most evenings. If it's a fatty meal, I will lengthen the gap before taking more insulin. I play it by ear looking at the trend line and XDrip+'s approximation of CoB and IoB to give me a steer as to how much more insulin to take. I find that if I let the activity curve (at the bottom of XDrip+ - i.e. how much insulin is active) drop too far I will rise, so I try to give more insulin before this happens (which may be when I have ~2U IoB remaining.) It's very much based on experience though.

Just as I'm typing this a secondary rise is kicking in bolus is still active though thankfully. Yeah just been trying to see what other people do getting some ideas I've had some mixed success so far but always a learning experience with each time think I might need to be abit more aggressive with certain meals based on what I see. I need to fully finish setting up xdrip when I get chance!

 

[everydayupsanddowns]

Out of interest do lager doses of Insulin kick in faster? Yeah I currently do 60;40 split with a 2 hour split which has sorted of worked at times maybe need to do a bit more even as I find I can halt the rise but then doesn't come down

I think expert opinion varies, with many experienced consultants saying the size of the dose (eg a correction) makes no difference to how fast it acts.

That has never made sense to my simple brain though. After the standard theoretical wait for bio-availability (10-15 mins) surely a 0.5u dose only has a proportion of 0.5u available, with the rest waiting to be used over the 4ish hours of duration. But a 5u seem to me to have more potential BG lowering effect, and so more of it is available at every stage of its action?

So I always assume a bigger dose will act more strongly early on. Because there’s more of it available?

 

[rebrascora]

I think expert opinion varies, with many experienced consultants saying the size of the dose (eg a correction) makes no difference to how fast it acts.

That has never made sense to my simple brain though. After the standard theoretical wait for bio-availability (10-15 mins) surely a 0.5u dose only has a proportion of 0.5u available, with the rest waiting to be used over the 4ish hours of duration. But a 5u seem to me to have more potential BG lowering effect, and so more of it is available at every stage of its action?

So I always assume a bigger dose will act more strongly early on. Because there’s more of it available?

I find with Fiasp, that if I want to skip my prebolus time and eat straight away, more stacked/split insulin works. So for instance yesterday I had a fruit scone (very rare treat for me). I was on about 5mmols, so I jabbed 5units for the scone (approx 50g carbs) and ate it with a nice cup of tea straight away. My high alarm went off about 3/4s of an hour later at 8.1 with a vertical upwards arrow, so I jabbed another 2 units and that kept me under 10 although I had a couple of mint imperials (10g carbs tops) on the drive home afterwards just to slowly keep me topped up and I leveled out nicely on 6.6 for the rest of the evening. If I had waited 20-30 mins and then eaten the scone, 5 units would probably have been enough.
I find with Fiasp that the higher my levels go, the less responsive it is (even between 7 and 10mmols), so I have learned to be really quite assertive with it and very proactive in keeping my levels below 10 as much as possible. This is one of the ways that Libre makes my life with diabetes so much easier for me and the relatively short action of Fiasp complements this way of managing my diabetes. I know that if I overdo it a bit, I can always have another 5 or 10g carbs later to level things out and because I don't eat many carbs to start with I can "afford" an extra 10g carbs a day if I need to.

I am not suggesting others do this unless they are very confident with managing their levels as it could be dangerous, especially if they follow a normal diet. My low carb diet means that protein is often slowly releasing in the background to buffer any fast drops.

 

[nonethewiser]

Out of interest do lager doses of Insulin kick in faster? Yeah I currently do 60;40 split with a 2 hour split which has sorted of worked at times maybe need to do a bit more even as I find I can halt the rise but then doesn't come down

No it doesn't, although obviously larger dose will drop you quicker if you don't match it with carbs.

 

[Proud to be erratic]

I think expert opinion varies, with many experienced consultants saying the size of the dose (eg a correction) makes no difference to how fast it acts.

That has never made sense to my simple brain though. After the standard theoretical wait for bio-availability (10-15 mins) surely a 0.5u dose only has a proportion of 0.5u available, with the rest waiting to be used over the 4ish hours of duration. But a 5u seem to me to have more potential BG lowering effect, and so more of it is available at every stage of its action?

So I always assume a bigger dose will act more strongly early on. Because there’s more of it available?

That, @@everydayupsanddowns, also fits my relatively limited experience.

Sometimes, mainly applicable to mornings, I need to do a modest correction but can't join that up with my breakfast bolus at that moment. Different reasons mean breakfast is not going to happen for a while. So I'll take that small correction and invariably it takes ages (2-3hrs) for the correction to take effect. However if I take a modest correction along with a well counted (standard) breakfast bolus then the consequences of the overall bolus are much more prompt, even to the point that I can't delay my breakfast and need to eat something fairly urgently to head off the incoming low.

I am alert to this "erraticness", yet I still sometimes get caught out. If I am even mildly active between bolus and eating (by mildly I mean just small clearing up jobs, eg emptying or stacking the dishwasher) then that mild activity seems to accelerate the bolus response - but not in a way that I can quantify or predict.

I was somewhat reassured some 20+ months ago when my Endo told my wife that I routinely made some 300 D related decisions daily, such was the nature of this "Complicated, Confusing and Contradictory" ailment [ref Gary Scheiner, Think Like a Pancreas]. It is invariably confusing sometimes @digihat; one saving grace is the more frequently things become contradictory the more it starts to just become my normal!

 

[Proud to be erratic]

No it doesn't, although obviously larger dose will drop you quicker if you don't match it with carbs.

That response, @nonethewiser, feels contradictory in itself. And it is also not my experience to date, with NovoRapid (see my earlier reply).

 

[nonethewiser]

That response, @nonethewiser, feels contradictory in itself. And it is also not my experience to date, with NovoRapid (see my earlier reply).

It's not contradictory at all, find speed of action of fiasp, which currently use is same regardless of dose given, found same with novorapid before fiasp usage.

Once insulin kicks in a higher dose is obviously going to drop you quicker if you don't eat for whatever reason, that's my point.