Here in the Feline Health forum the "pause and think" number is 200 mg/dL. It's more of a "stop and think about what you want to do" than an absolute "No shot, don't give insulin" number. Think of it as a threshold, a stop and ask for advice or stop and review the protocol BG number.
In the ISG's (Insulin Support Groups) that "stop and think" number varies depending on the insulin used, the experience of the caregiver comes into play, the amount of test data comes into play. If you have to rush off to work, you don't know if your cat will eat food while you are gone, then a reduced dose may be appropriate. With a depot type insulin like Lantus/Levemir/Basaglar, you don't want the depot to drain too much by skipping the dose. If the cat has ever had ketones, DKA (diabetic ketoacidosis), HL (hepatic lipidosis) then you don't want to skip a dose entirely if you can help it. Ketones = fat and muscle breakdown = DKA with not enough insulin.
For Lantus, the threshold, the initial decision point number is 150 md/dL. Same for Prozinc. WITH EXPERIENCE and some test data. First day here, first week or so on insulin for your cat, you don't know how your cat will react to the insulin, keep that threshold higher. As you gain test data, that threshold will get lower and lower. Our #1 goal is to keep your cat safe.
I'm afraid she will bounce at her PMPS because I had given her a dose on such a low bg.
For future reference would giving her a 0.1 dose on a low number like that be the best idea?
On that 147, 148 I would have gone ahead and given Bear the full 0.25U dose. AFTER you have stalled, not fed, and tested again in 20 minutes.
If she does bounce, then she bounces. Not the end of the world.
With lantus, there are people shooting insulin at lower and lower pre-shot BG readings, under 100, even lower than that. You have to collect the data to be ready to do that. Here is a good "Sticky" post from over in the Lantus ISG on how to do that. Basically the axiom "Know Thy Cat" comes into play here.
Sticky Tight Regulation: Becoming Data Ready to Shoot / Handle Lower Pre-shot Numbers
Some of the other insulins like Vetsulin/Caninsulin and the NPH insulins like Humulin N/ Novolin N have a faster onset and steeper drop, so the threshold for giving insulin is higher, 200, 250, 300. As you gain experience with how YOUR cat does on an insulin and a particular dose, that threshold can be lowered.
Is your cat a food spiker? Is your cat a picky eater? Know Thy Cat.
Highly recommend that you print out and read the "becoming data ready" sticky I linked above.