Get the pre-testing done for sure and request a meeting with the vet beforehand to discuss options, I think that will help ease your worries.
Personally I've gone through surgery twice under GA and reacted badly both times, last time I stopped breathing and they had to intubate and bring me back. Sometimes you just react regardless which unfortunately seems to be my case. No rhyme or reason and pretesting was fine. So I'm a serious worrywart when it comes to surgery but thankfully both of mine have come through with flying colours and no complications
Jasmine - Female Miniature Poodle - born Aug 15, 2010
Loker Delgado Von Stalworth - Male GSD - born Jan 26, 2012
Koda & Zazu - 5 year old male cats
Alex - Male Cocker Spaniel (rescue) - RIP Cuddlebug 2007-2010