my dog started inverted sneezing a day or so after surgery is ther a connection or coincidence

What you are describing is more likely a "reverse sneeze."  Most of the time, a reverse sneeze is not considered to be a problem and will usually correct itself within a few moments.  There can be medical reasons for this type of behavior, such as allergies or mites in the upper respiratory tract but, most of the time, a cause will never be established.

I am enclosing a web site reference for further reading:

http://www.vetinfo.com/reverse-sneezing-dogs.html

As you can see from this article, something as simple as excitement can cause a reverse sneeze.  Whether or not your dog's reverse sneezing was related to the vet visit might not ever be known.

Helpful Buckeye