We went out for a relatively late dinner last night (always a mistake, but no choice in this case). My 10 year-old son with Type I ordered a grilled cheese sandwich and it came with a huge plate of fries. Usually we have the fries on the side and give them to him in small (20 carb) batches, but this time he was so hungry that we just let him go. He ended up eating the whole plate, which I guestimated was about 60 carbs. We dual-waved him and he was pretty good for about 4 hours (actually on the low side so we gave him a touch of juice). Then around 12:30, maybe 4 hours after dinner, he started going up and up and we couldn't bring him down all night. We ended up giving him as much insulin over night as he got for his entire, very high carb, dinner. Certainly I could have been off in the carb counting, but not by that much. We've seen this before, and it usually has to do with large, high-fat dinners. Obviously fat delays absorption of carbs but does it have other effects that would explain needing this much more insulin? Does it cause insulin resistance or reduced efficiency?
Based on the info you gave, it has to be more carbs than you thought. A large McDonald's fries is 63 calories, and a whole plate of fries could easily be double that. Plus perhaps 25 for the bread in the grilled cheese.
One factor that could help explain the timing of the low and later high is that larger meals take longer to digest. Sounds like you were on the right track with the two waves. Perhaps a smaller initial wave and a longer, bigger second wave would have done the trick.
Bruce, you are right about absorption of carbs when fats are involved and you may need to experiment some / lots. I've been trying for years to calculate dosages when I eat fries. and not I avoid eating them - although I did have a good serving of them last night. Using the large McDonald's serving (6 ounces.) as a guide; 570 calories, 30 g fat, 70 g carb figure you son had at least 100 grams of carb for his supper last evening. And considering the lateness I'm assuming that his BS was at a moderate or low point, giving him a bolus for 100 grams of carbs - even a dual - could cause him to drop too low. In a situation like this, I advise splitting his insulin into two or three boluses: with the meal, a moderate bolus; test after three hours and give the balance bolus being careful not to stack too much insulin in his body. Cautious experimentation over time will help - but being close to his bed-time extra caution is needed. The delay in blood sugar rising is common; last evening two hours after my serving of fries [and other foods] my BS had gone up only 6 points [not significant] but by 4 hours after my square bolus was started it had gone up another 100+ points.
I'm realizing Bruce that the above may not help in counting fats and how to allow for them in calculating bolus. The major thing to remember is that fats slow absorption and they have a dramatic effect on blood sugar of a person not accustomed to them.
The guys are right about fat slowing digestion, but there's more to it. When you add fat to carbs it dramatically increases the amount of insulin needed because the fat causes your liver to release glucose. Gary Scheiner give a good explanation in this link:
Bruce, aside from all the things that everyone is saying - which are true - you might consider teaching your son about eating healthy choices. I am not a organic food preacher, but I have found that since changing my diet to NON-GMO products, grass fed beef and no MSG - which is hidden in many foods with many names, your son will stay healthy for a long time. It's difficult not to eat yummy food and when I was 10 and had diabetes I was told no ice cream .... it goes on forever. It's better to eat apples, oranges, fresh greens ... and I was not raised that way ... I had to find that our food supply is killing us ...
that's very interesting and explains what we've observed. I'm not sure I'm brave enough to give him a 150% temp basal for 6-10 hours after an 8:00 dinner though. Not without staying up til the wee hours of the night.
I agree, avoiding is definitely the best strategy! That said, he's pretty good for a 10 year-old. He's a vegetarian and a pretty wide-ranging eater. The balance we try to find is not to have him be so restricted that when he is making his own choices he makes poor ones just because things have been denied to him. So sometimes we say "yes" to a big plate of fries even though we know it's going to make for a difficult night, just so that being a kid with Type I isn't quite so hard for him.
That's great and you are probably doing the right thing -- we all love to have fun with food. Neat he's a vegetarian! I am not there yet ... but slowly seeing what is really in our food makes me sick. I wish him many years of health and maybe he'll be around for a cure .... I've been waiting on that cure for the last 20 years!! The keep talking about it ..maybe it's just one of those things they want you to believe in ?? I am a skeptic by nature!
I'm not brave enough to take a bunch more insulin in case my liver dumps glucose either. I usually slightly overestimate my dose, then correct the high on the other end. In the past I've tried to track specific meals and that helps. But it's never perfect.