Sammi had that lampshade (Elizabethian collar is the vet name) on her when I took her home from spaying...She was totally knocked out from the drugs, so I took it off after we got hom...My vet made her a "onsie" out of ace bandage, so it was breathable...
Here is a pic of Sammi in her lampshade

and one of the onesie my vet made