The cat's metabolism is much faster than a dog, so N type insulins don't last 12 hours for them - more like 6 - 8 hours, leaving 4-6 hours with no insulin. And you just fought off DKA, so we want to get insulin in him whenever he needs it. A half bathroom and a big towel may go a long way towards helping get the tests and shots done. Set up everything in there, including a low carb treat. Bring the cat in and shut the door. Burrito wrap the cat if he's too squirmy, otherwise, just put it on your lap.