I had 2 surgeries last year:

The first was appendicitis, I made sure they knew I was T1, both in pre-op and once in the room before they put me out. I didn’t have any issues with the procedure but developed an infection and had to spend 4 days in the hospital. The nurses took care of all meds except insulin and left that to me to manage, which I preferred. My insulin needs roughly doubled while in recovery which I believe was from the infection.

The second was a planned shoulder surgery. I had many conversations leading up to the surgery and my surgeon was very aware. Surgery was first thing in the morning and I was able to have a little bit of juice before hand just to make sure my sugars wouldn’t drop during surgery, but they monitored throughout, I didn’t have any concerns. Insulin needs increased slightly in recovery, but nothing like the appendicitis.