Would rash under breasts cause PS to not operate?

The rash is one of the reasons for approval for the surgery.
The rash reactivated a few days ago and causes spots down one rib cage and in my armpit.
I am using a medicated prescription cream from my GP and showering 3-4 times a day. It is hard to think of getting properly dressed (wearing a bra,etc.) when I'm wet and slimy at the bra site!
I am having a hard time waiting and want to be after the surgery already.
At this point my pre-op is Th and surgery next week on 1 August. I'm hoping the PS will be the same as who I had for my TT but as it is a public hospital and Dr.Haik is head of the Burns Department adjacent to Plastics (he is the Vice Head of Plastics) it all depends on what is going on in the country between natural burn explosions, terrorism and the Newest Trend of people struggling with major financial debts and burning themselves up in the middle of demonstrations - two successful ones and two ar three other attempts in different cities. But I digress.
BUYING SURGERY BRA-- I have to but my own ( hey I'm not paying for surgery!) and I'm very worried I'll but the wrong thing. My PS wants a triumph front-closing sports bra in black ( black so one foes not freak at seeing normal surgery discharges). I checked several shops and most don't carry it in black or that brand. And I'm confused as to what size to buy. So I will buy st my next pre-op in the Intimates Ladies Shop in the Mall of the hospital so if there is a
problem I can show the doc and exchange if need be.
ANY TIPS I should know for when I leave the hospital - I'll probably be in about a week. BREAST LIFT/REDUCTION with TT scar revision.
Mikimi in Israel

 How long have you been using the cream? I am allergic to the prescription strength deoderants. Also, it could just be from sweating. What I do when I am sweaty with a rash is I either put on some deoderant/antiperspirant or I put on baby powder to take away the moisture. It usually goes away after a couple days. Just do your best to keep the area dry. I'm not sure if they will postpone your surgery but it might happen. You wouldn't want that extra discomfort after PS. 

This is an antibioticsteroid cream . I know once the surgery is done I will be fine as I was with my TT.
I don't use deodorant although I did try using toll-on that worked a long time ago but not anymore.
Will update on Th after the Pre-Op.
Mikimi

 You need something with baby powder in it.

Mikimi, one thing that used to help my mom when she had the under the breast rashes was maxi pads...just the cheap thick ones...she would undo the sticky for two of them, put them sticky sides together and put it under one breast, then repeat for the second breast. It helps keep things sanitary and helps take the moisture out.

Baby powder with NO FRAGRANCE other than the original...if you dont have "Johnsons baby powder with cornstarch" in Isreal then plain corn starch will work too, just use it like a powder. 

The pads may feel weird because it will be lumpy but its a little better than having irritated skin rub agains irritated skin.  I also had to do this a couple times for my pannus so far.  

Hope this helps !

To tell the truth I'd be afraid the pas would slide out from my bra as my boobs keep doing these days. I did try medicated powder a friend brought from the States and it burned.
I'll know more by tomorrow afternoon if my Op will be on schedule.
With my TT my under-pan us looked like red chapped lips on a child in winter! And they did my surgery.
Thanks for your suggestions.
Mikimi