Fixing head retention after kegging

I made and kegged an oatmeal stout and it pours with a nice head. Unfortunately the head disappears in under a minute. I'm guessing I had some residual soap in the keg... Haven't had this happen before. Is there anything that can be added to fix this? Any tricks to try?

 

Soap residue isn't the only cause of a head collapsing. Oil will do it too. Oil like is in oats. Did you use flaked oats in your oatmeal stout?

 

Yes. I used 1 lbs of Quaker oats that were from the grocery store. Is that an issue?! I thought I had read that was fine to do.

Any way to fix it now?

 

Your choice of oatmeal from the grocery store is fine, all rolled oats have oils in them. You may just have to drink that oatmeal stout without a head on it. If the is another fix, I'd like to hear of it too.