Had Facial Laser Vein Removal, then Got Impetigo. Will It Scar?

Impetigo after any type of cosmetic treatment can have implications in terms of scarring and should be treated aggressively by a dermatologist. 

The blisters you describe after any laser to the face can be viral infection as well. Viral infection can be superimposed with bacterial infection and if it goes deep then yes it has the potential to scar. That is why the treatment should be fast and aggressive for both bacterial and viral infections.

If the impetigo is treated promptly with a topical or oral antibiotic, there should be no scarring,since this is a superficial infection. It may remain red for a few weeks, but that will go away. Remember that impetigo is contagious, so use separate towels until the infection has resolved. If you get several bouts of impetigo it may be worth seeing  a doctor to see if you are a carrier of the bacteria called Staph aureus in your nose. That has no symptoms.