Undescended Testicles 13 month old

My son is 13 months old. We had his 12 month check up. The doctor let us know he could not feel his testicles in his sack. Monday we had an ultrasound and both his testicle are in inguinal canal and undescended. My doctor hasn't called yet regarding the results. It looks like the only option is bilateral orchiopexy surgery. This is a surgical procedure that moves both testicles into the scrotum to correct undescended testicles. It's recommended by 18 months. If gone untreated he is more at risk to develop testicle cancer and infertility later in life.

I'm a first time mom and so nervous! This should be an outpatient surgery. Has anyone gone through this with their son? Did they have to fast prior to having the surgery? I nurse my son to sleep and he wakes up wanting to nurse so that will be hard for us if he can't have milk. Any experience and advice is appreciated! Thanks!