Not sure how many hrs after your meal that reading was. If it was over 2hrs post say for eg, 3 hr post it sounds like you need a basal like Lantus, as you did before.
The rapid acting insulins are there to cover the 1hr - 2hr post readings. If you dont come back to baseline and say spike 3 hr post, it means you need a basal dose on top of the sliding scale. This should give you much better coverage. Otherwise you run the risk of increasing your rapid acting and risk crashing 2 hrs post and then you'll find is that you'll start creeping back up 3hrs later etc.
CFRD is really complicated. There are indiv differences in how one CFers pancreas responds ie how much insulin it secretes and when, on top of the ususal underlying variances that affect glucose levels, like inflammation, fevers, physical activity. I do think, that unfortunately some CF teams tend to overlook the specialist care that CFRD needs. It's almost acts like a combination of type 1 (eventhough it is obviously isn't an immune response in us) and type 2.
Exercise is a great way to assist w insulin resistance (as seen in type 2 diabetes). It forces the insulin that you do have circulatinng to do its job and transport the blood glucose to your muscle for energy and thereby reducing your blood glucose readings.
Take care. Watch for hypos, they can creep up on you in CFRD (I know thats not what you have) because your pancrease still secretes insulin although, inefficiently and in a delayed manner but, it still will release some insullin so, hypos can happen hrs after a meal. I find that they are more intense to treat than what the average diabetes educator will tell you to take for it eg the standard 3 or so jelly beans I have been told to take for hypos just doesn't cut it for me. As you know, each CFer is unique. Carefully monitor yourself.
