@shelby29 I'm not sure where you read about Gatorade, but I doubt if that advice is medically supported.

Hydration is always important, but especially before and after (any) surgery to help flush the remnants of anesthesia from your system and to promote healing. You will also probably be given IV fluids before and during surgery.
But sugary drinks are not more effective for hydration than plain water or herbal tea. Perhaps thay were thinking it was necessary to replenish electrolytes to help after the blood loss during surgery? There are a lot of electroyte replacements that are low in sugar like Propel (powder or liquid.)

Drinks to avoid or minimize are those with a lot of caffeine or alcoholic beverages. (That doesn't mean you have to give up your morning cup of coffee-just don't drink a whole pot.)

Good luck with the surgery.