This is just what I was telling my consultant about this morning and that I've learnt to guesstimate what to do. To be honest the specialists don't really have much advice. The way that I deal with it is that I wait until my BG has gone up to 10 - I then have two units of Humalog, wait to see if that has worked and if not give myself some more if I need it - which if it is the momrnig I do but if it is evening time I may not need the extra insulin until 2am, 3am, 4am - there is no set time.. If my BG is under 9 before I go to bed I don't have any humalog because the food is obviously not going to digest until later. I usually only have to do this for lunch and my evening meal. It's not ideal but I haven't been able to find a better solution - and my consultant thinks that I have one of the best HBAC1Cs that he has seen in someone with gastroparesis.
However it is not straightforward. I am worried that your tummy is full first thing in the morning - although that is probably from food still being in there from the night before. Fortunately for me a combination of domperidone and errythromycin means that my tummy is empty in the morning so I can usually carb count for that meal only (if I'm able to force myself to eat because I feel nauseous first thing/don't have an appetite). Lunch is more tricky and then, for me, the evening meal is the worse. I hope this post makes sense but if it doesn't please let me know