I read the procedure. There is most definitely a problem with giving too many fluids sq continuously.
Subcutaneous Fluids in Dogs Initially treating fading puppies and kittens - Veterinary Medicine
IMO, there are a lot of vets that would say not to give a hypertonic dextrose solution SQ. You definitely will be able to find what you need online, but it's just so much safer to have your vet prescribe it. Then they will give you the fluids that they want you to use.