He has a good mama.
You've got a bit of a balancing act going on here. With the infection you need to be a little extra careful with the high numbers. With the harsh insulin, major history of hypos and treatment of the infection all going on you need to make sure that Woody doesn't go low (quadruply so when you need to be out during the day and can't test from +2 onwards).
Here are some options to consider:
1. Give 1 unit and see if it takes him too low tonight. (This will make sure he has insulin but carries the risk of him going too low.)
2. Give ½ unit and see if he levels out and dips down a bit during the night (hence the question about monitoring). There is a chance he may stay in the pinks but there's no way of knowing until you try and test. (Because Woody has an infection the smaller amount of insulin may increase the risk of his developing ketones.)
3. Give 0.75 units as a 'compromise' and test to see if this will lower his BG better than the 0.5 unit dose. (Don't know if you can measure this dose relatively accurately with your syringes - plus it's an unknown quantity.)
If I were in your shoes and working with a harsh in-out insulin like Novolin N (and I'm just speculating here) if I knew that ketone risk was higher than normal I would
possibly look to keep numbers higher and safer when I could not monitor and perhaps just a little bit lower (but still in the high 100s at nadir) when I was home at night and knew I could monitor to keep my cat safe over the night time cycle.
Conjecture, but that would be the 'flavour' of my approach. Other members may have different suggestions.
Mogs
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ETA: The infection causes two issues:
1. Greater risk of developing ketones while it is ongoing.
2. Risk of numbers dropping unexpectedly if it resolves.
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