Cataract operation phobia and concern

I am having a cataract operation soon, but i have some concerns. i will be given sedation in the form of tablets, because of claustrophobia, but i do not know how strong that will be, i also suffer from various medical conditions, rheumatoid arthritis, and Ulcerative colitis, which make it difficult for me to lie still and i can not lie flat on my back. Hope somebody can answer some questions of concern to me.
Do you have to lie flat on your back?
do you have to lie still?
how well do these medications for sedation work?
At the dentist, i get gas and air so more or less out of it, which i am looking for.
How soon can you drive afterward?

I’ve had sedation for tough dental extractions. Like the date rape drug, you can follow instructions but remember nothing! Highly recommended!

Hi John, Another alternative is you could ask for a general anaesthetic instead.

Yes, that is what I normally get, or gas and air, but they only do sedation tablets here and I am trying to get an opinion about how well they work like you say you remember nothing.

Hi John,
S had an sigmoidoscopy and gastrocoscopy under sedation. He has autism and was very anxious. During the procedure he seemed aware (I was with him) however, he slept after the procedure and had no recollection of it after - he thought he hadn’t had it yet and was very surprised when after his drink and toast they said we could go home.

Have you explained your concerns re lying flat and still? What did the consultant say?