Pedialyte, especially unflavored, is just water and dextrose, with less than 2% of Potassium Citrate, Salt, Sodium Citrate, Citric Acid and Zinc Gluconate. Technically it is significantly less salty than lots of things people give fids, so itās probably ok - but again, Iād call a vet. They really, absolutely shouldnāt mind answering these questions for you.
I have also heard of offering coconut water to fids- it similarly contains naturally occurring salts.
My parrot emergency kit is cornstarch, Benebac, syringes for giving oral meds, and a VERY thick towel for restraining (but my birds are on the larger side). I also have a t-stand, dowel perch (for moving an angry or injured bird without risking my hands, haha), travel cage and gram scale. The gram scale tells me almost as much as his poop as far as how heās feeling - his weight was down 20g when he had a bacterial infection!
Sterile gauze, vet wrap, cotton swabs, and cotton bandages are also great. For birds who are not eating, feeding tubes of the appropriate size (there was a thread somewhere here where people posted a lot of great sizes for budgies) and handfeeding formula are fantastic to keep on hand.
To round it out, an incubator, or heating pads/cage warmers, or even something as simple as a hot water bottle that can be placed under a towel in a travel carrier are excellent to have for sick fids. Sterile saline is useful for rinsing wounds or other applications as directed by a vet (ours had us using sterile saline nose drops to keep our parrotās nostrils clear one winter).