A couple of years ago I had this surgery for my left kidney. I have had stones for 8 years (it'll be 9 in Nov). I originally started w/ multiple lithotripsys that would break the stone but always leave some in the kidney. At one point the Dr decided to wait a year since the stones that were left were small. A year later, it had gotten large so they said I need the surgery w/ the tube in the back. I don't know if they have changed the way they had this procedure since then, but it was painful and uncomfortable but then the litho and stents are also painfull
I was awake while they put the tube in the back because they needed me to breathe & either be full or empty of air as they put the tube in until they got it where they needed and then they knocked me out.
They did get most of the stone out at that time but a bit was left in. The worst part was having the tube in the back for the 7-10 days.
I don't know if this is the way they still do this type of surgery anymore. The advantage to this surgery is they get more of the stone out plus they bring what they can out through the tube so you don't have to pass them the regular way.
I hope all goes well with your surgery.