Hi Ed.
You need to get in touch with your GP and also the Hospital where you are having the Operation ASAP.
I went for an Operation on my knee once and was all gowned up, waiting to go down to Theatre.
A few minutes later the Surgeon comes up to me and says,
" How long have you been a Diabetic ? "
I looked at him blankly, then said,
" Probably about thirty seconds !!! " :?
That was my diagnosis of Diabetes. Needless to say, my Operation was immediately cancelled and took place a few weeks later.
Ken.