I Am On Sinemet. Amantadine And Azilect For Parkinsons. I

I am on sinemet. amantadine and azilect for Parkinsons. I am pretty sure that I am going to need major surgery to repair a huge abdominal wall hernia. I am aware that suddenly discontinuing any of the above named drugs can result in dire consequences. But, every time I've been admitted to the hospital for major surgery in the past, most of my meds - except for insulin - were discontinued temporarily. My last major surgery was before starting the Parkinsons meds. I'm really scared. What do I do?