Style/abbreviation in diagnosis question - jld

Okay, normally I wouldn't leave an abbreviation in the diagnosis section of a report (or operation or procedure at the top of an operative report) without at least putting the expansion once in parentheses after it. Usually, the only time I leave it is when it's a trademark/brand name that is always used in abbreviation form.

Well, now I have a dilemma. One of the procedures being performed is pulsed lavage with GU irrigant to some diabetic foot ulcers. Normally in the body of the report I just type GU irrigant, but since it's in the top of the report where I don't normally leave abbreviations, it's bugging me. I know that the GU usually stands for genitourinary because it's often used to irrigate the bladder. However, of course it's an antibiotic-containing irrigant that is used for other purposes, too.

Now in researching it, I find that a popular irrigant is the brand name Neosporin G.U. (which has the periods in the name--though I've never transcribed it like that) irrigant. If I knew for sure that it was that irrigant, then I would feel fine leaving G.U. (with the periods as a brand name) in the OPERATION section of the report. However, I don't know that that particular brand is necessarily being used. I mean, it could be a generic irrigant, right? With the polymyxin and neomycin in it that they just call "GU irrigant" because all the doctors know what that is, even if being used on a different part of the body?

So should I put something like "Pulsed lavage with GU (genitourinary-type) irrigant of ulcers."

or

"Pulsed lavage with G.U. irrigant of ulcers." (assuming that it's Neosporin G.U. irrigant)

or just leave

"Pulsed lavage with GU irrigant of ulcers." (and just get over my having to always expand everything up top, because common, accepted abbreviations like this are permissable)

Opinions? Thanks in advance.