The "doctor's lounge" in most hospitals is not some large living room, but isually a few chairs and a coffeepot near the dictation area. It is indeed reasonable -- and often a good idea -- to discuss clinical matters there, where useful information can be exchanged in relative privacy and informality, whether in the interest of a mutual patient (for which patient permission is rarely required, though often good to get), as an informal clinical consultation, or for some educational purpose (such as discussing the merits of a treatment or procedure, and perhaps giving important examples). The point of my earlier comments was not to discourage any of those.

The issue is privacy, especially when patient identification isn't clinically relevant to the discussion, not location. Putting a gag on clinical and professional communication between doctors (and other health care professionals) would be a very bad thing to do.