Hi, welcome to our site. I am Dr Saumya Mittal.
Read your query. That is a very significant question and i appreciate your problem. I will try my best to answer your query
if the sugar is normal, the patient of
diabetes may be treated in many ways
1. as you said, dont give any
insulin, just normal saline
2. you might start the GKI drip, or mix insulin in dextrose containing fluid and let it go
3. the patient may be given nothing. in a long surgery the sugar is regularly checked and informed to the diabetician who may administer insulin accordingly
there are many other ways
the choice of treatment depends on the treating diabetician
I hope this helps you.
Looking forward to your return query so that I can help you further.
(If the answer has helped you, please indicate this)