when you are going to have surgery

how detailed does the dr have to be about the disadvantages? if they didnt discuss the bad things that happened to me, how would i know if they could be liable, because what happened to me was not discussed, its not death, not sure if that is what would have to happen? also, i got my medical records from drs office, and in the drs note, she got a few things wrong, does that happen often? thanks