Has anybodies dogs had this, and how did you manage to kill the bacterial infection, my poor Rottie has suffered from it for a while, and nothing seems to kill it.

I don't know how pseudomonas acts is dogs ears but I do know how it works in human damaged lungs and once you are colonised by pseudomonas, because even though it is sensitive to antibiotics, it creates a tenacious biofilm, some of which remains even after antibiotic treatment.  You can only 'dampen' it down but it will always be present and will always flair up again.
This may not be the same for dogs ears, but it is a horrible bacteria.

Looks like it is the same for dogs ears, I found this on the web:
Dog ear infections mostly involve pathogenic organisms that are sensitive to antibiotics and are easily treatable. After an antibiotic treatment regime, most of the bacteria are killed but in certain cases the residual infection is of a resistant and literally immortal bacterium called pseudomonas.

Pseudomonas is a special species of rod-shaped Gram-negative bacteria, resistant to every antibiotic known to the medical world. Gram-negative relates to bacteria that do not retain the violet stain used in Gram's Method.

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