What questions should I ask, RN, dietician and surgeon?

My next meeting is with my dietician. What questions should I be asking her? I am getting a medgem done this time. 

Does anyone actually now what our RN does for us? 

I meet with my surgeon to ask questions soon. What questions should I ask? 

What is a megdgem?

MedGem is a metabolic test. It tells you how many calories you burn in a day if you didn't do anything.  It takes about 15 min. 

I had to bring a 3 day food diary. We talked about post op diet, vitamins etc... they want to hear that you are making dietary changes pre-op such as cutting out pop, junk food, eating healthier. It is also a great time to discuss dietary likes dislikes. Ie hate cottage cheese and yourgurt wwhat are the alternative.

Tthe nurse just does vitals, measures waist, neck. Review symptoms of sleep apnea. I had brought a copy of recent blood work and sleep study i had done. Appointmet didnt last long.

For surgeon it is time to ask questions. What are they doing, review risks, if cant do rny may have sleeve etc...