Aspirating swim bladder: Oscar illness

[sharn]

A quick run down of the situation, am looking for 'where to next's'...

Oscar fish, approx 8 years old. Off food for a little over a month, ate a few pellets here and there, turned nose up at juicy foods such as frozen deshelled snails etc (very out of character). Never had live fish as food, and no new tank mates in years. Began head standing about a week and a half ago. No signs of visable out of the ordinary swelling, no raised scales etc. Moved to a quarentine space, treated with furan-2 as per reccomended dosage for suspected internal infection. Increased temperature to 29C throughout treatment. Added 1tbsp/20L of both rock salt and epsom salt, replacing what was removed from water changes. Bouancy slowly went from gentle head standing to laying left side down (right side is boyant). Have been massaging the intenstinal area daily for the last week (I then suspected a potential blockage gone spetic), with a light rub over the bladder. I can support the fish to release a small amount of *something* from it's anus, which is green/spirulina coloured and intially tar like in substance, very watery and dissolves to nothing. After completing the treatment of furan I gave the fish a few more days in quarentine, before moving it back into the main tank to assess its movement. This just caused it more distress as it had to actively work to keep itself at a depth of 60cm, so removed back to quarentine.

Now the right side is beginning to increase in size, in the rear 1/3 of the fish where the end of the bladder would be, no scales sticking out yet. I am considering aspirating its swim bladder as a last resort... Haven't done this before, but if all else fails, it is worth a shot before euthanasia. Thoughts? Other ideas for treatment?