Hi welcome to Health care magic forum.
Thanks for calling H.C.M.F.
The fluid in the abdominal cavity is called ascitis. and is caused by either secondary to liver
disease, or Intestinal, or gynic problem. Thick fluid suggest malignancy, or some thing of that sort
I advise you to consult a general surgeon
, For diagnosis and treatment. You may need to have M.R.I. examination of the aspiration liquid, besides other routine tests for confirmation.
I advise you to consult a surgeon at a multi speciality hospital, so that the doctors in case of doubt can refer to oncologist
in the same hospital, or may treat in combination of the other doctor.
Wishing a quick and complete recovery.