Just thinking out of the top of my head (might not be any help, if not sorry)
Do you have a ketone meter at home? If not perhaps you could talk to your nurse about it.
If you were able to test for ketones at the first signs of illness ( or perhaps even on a regular basis?) then with the help of your nurse you could devise an action plan to try to prevent low levels of ketones developing into DKA. (ie drinking fluids, taking extra insulin compensating with sugary fluids if your levels are low)
A cheaper alternative would be to use ketone urine strips daily, following up with blood ketone strips if necessary. Indeed I use a pump and when I first went on it the consultant wanted me to test every morning as mistakes with the pump can mean being without insulin for several hours.