I apologize for inconveniencing you with my insignificant post. Was not my attempt to make a "big deal" as I was simply interested to see how other colleagues felt about this insignificant, non-issue. I, too, have had MD's address me as "Mrs." and I address them as "Dr." and every now and then with an attending, I may even throw in a "sir" but that was not the question; "ma'am and sir" was the question in the OP. The other nurse, who brought it to my attention, is also male and it actually disturbed him more than it did me, so I wondered if it was related to male-male interaction. Rest assured that no "big deal" was made of the original incident; we all left the shift holding hands and singing "Kumbaya" as it was our last night for 7.
To everyone else who replied, thanks for your input. I am with the majority in that I tend to offer and address depending on the amount of respect I am shown. Only thing different with me is that I absolutely refuse to call them by their first names, even if they address themselves by first name. I personally feel that they deserve the title of "Dr." simply because of the hard work and sacrifice necessary to become a MD.
Altra, I like your observation. While he is a very respectful young man and does address everyone the same as the docs, I do believe he over uses when speaking with a doc because it stands out (both of us had noticed it without it being pointed out); it's almost excessive. He intended no disrespect to coworkers or anyone, nor was any taken. We were just concerned with him setting himself up to be "looked down upon." He's a new nurse, lacking confidence, and I think that may play a role in his overuse AND our perception of how it could be interpreted.